Evidence review for percutaneous drainage versus resectional surgery for the management of abscesses

National Guideline Centre (UK)

NCBI Bookshelf. A service of the National Library of Medicine, National Institutes of Health.

Evidence review for percutaneous drainage versus resectional surgery for the management of abscesses

Diverticular disease: diagnosis and management

Evidence review N

NICE Guideline, No. 147

Authors

National Guideline Centre (UK).

London: National Institute for Health and Care Excellence (NICE); 2019 Nov.

ISBN-13: 978-1-4731-3603-8

1. Management of acute diverticulitis

1.1. Review question: What is the clinical and cost effectiveness of percutaneous drainage versus resectional surgery for the management of abscesses?

1.2. Introduction

Diverticular abscess represents a particular therapeutic challenge given the predominant age and frequent co-morbidities of patients presenting with the condition. There has been much interest in the use of minimally invasive techniques such as percutaneous drainage to minimise the morbidity and mortality that is associated with resectional surgery. However, no clear guidance is currently available to suggest which patients should undergo percutaneous drainage versus surgery or for the subsequent management of patients initially treated conservatively. This review of the evidence aimed to provide information for both clinicians and patient to determine the clinical and cost effectiveness of percutaneous drainage versus resectional surgery for the management of diverticular abscess.

1.3. PICO table

For full details see the review protocol in appendix A.

1.4. Clinical evidence

1.4.1. Included studies

In the absence of any relevant randomised controlled trials, six observational studies were included in the review;³^, ⁶^, ⁹^, ¹³^, ²⁵^, ²⁶ these are summarised in Table 2 below. The included studies provide outcome data for comparisons among antibiotics, percutaneous drainage and surgery, or combinations of these interventions, used in the treatment of diverticular abscesses. Evidence from these studies is summarised in the clinical evidence summary below (Table 3).

See also the study selection flow chart in appendix C, study evidence tables in appendix D, forest plots in appendix E and GRADE tables in appendix F.

1.4.2. Excluded studies

See the excluded studies list in appendix H.

1.4.3. Summary of clinical studies included in the evidence review

See appendix D for full evidence tables.

1.4.4. Quality assessment of clinical studies included in the evidence review

See appendix F for full GRADE tables.

1.5. Economic evidence

1.5.1. Included studies

No relevant health economic studies were identified.

1.5.2. Excluded studies

No health economic studies that were relevant to this question were excluded due to assessment of limited applicability or methodological limitations.

See also the health economic study selection flow chart in appendix G.

1.5.3. Unit costs

The unit costs below were presented to the Committee, to aid consideration of cost effectiveness.

1.6. Evidence statements

1.6.1. Clinical evidence statements

Antibiotics vs surgery

Evidence from 2 studies (n=2743) of very low quality was included in the comparison between antibiotics and surgery; however the committee agreed that due to the high level of selection bias they could not determine the clinical importance of the evidence.

Percutaneous drainage + antibiotics vs antibiotics

Evidence from 4 studies (n=289) of very low quality was included in the comparison between percutaneous drainage plus antibiotics and antibiotics alone; however the committee agreed that due to the high level of selection bias they could not determine the clinical importance of the evidence.

Percutaneous drainage + antibiotics vs surgery

Evidence from a single study (n=64) of very low quality was included in the comparison between percutaneous drainage plus antibiotics and surgery; however the committee agreed that due to the high level of selection bias they could not determine the clinical importance of the evidence.

Percutaneous drainage + antibiotics + surgery vs. antibiotics + surgery

Evidence from a single study (n=146) of very low quality was included in the comparison between percutaneous drainage plus antibiotics plus surgery and antibiotics plus surgery; however the committee agreed that due to the high level of selection bias they could not determine the clinical importance of the evidence.

Percutaneous drainage vs. antibiotics

Evidence from a single study (n=2922) of very low quality was included in the comparison between percutaneous drainage and antibiotics; however the committee agreed that due to the high level of selection bias they could not determine the clinical importance of the evidence.

Percutaneous drainage vs. surgery

Evidence from a single study (n=716) of very low quality was included in the comparison between percutaneous drainage and antibiotics; however the committee agreed that due to the high level of selection bias they could not determine the clinical importance of the evidence.

1.6.2. Health economic evidence statements

No relevant economic evaluations were identified.

1.7. The committee’s discussion of the evidence

1.7.1. Interpreting the evidence

1.7.1.1. The outcomes that matter most

The guideline committee agreed that for this review quality of life, mortality, morbidity, progression of disease, recurrence of abscess, re-hospitalisation, need for further surgery/percutaneous drainage, complications (infection, abscess, perforation, fistula, stricture and haemorrhage), anastomotic leak rate and stoma were considered critical outcomes. There were no additional outcomes that were considered to be important.

In this review, no clinical evidence was identified for the following critical outcomes; quality of life, progression of disease, recurrence of abscess, complications (infection, abscess, perforation, fistula, stricture and haemorrhage) and anastomotic leak rate.

1.7.1.2. The quality of the evidence

The evidence included in this review was of a very low quality primarily due to selection bias, a lack of participant and investigator blinding, and imprecision. Selection bias was present as factors such as abscess size and location, and the feasibility of percutaneous drainage, affected which group patients were assigned to by surgeons. All evidence was obtained from non-randomised studies, as no randomised controlled trials matching the review protocol were identified.

1.7.1.3. Benefits and harms

When discussing the evidence, the committee appreciated that in all included studies there was significant selection bias present for all of the reported outcomes due to the nature of patient assignment to each group. In particular, abscess size, location and the feasibility of percutaneous drainage impacted upon which group surgeons assigned patients to and may therefore have influenced the effects observed for the reported outcomes. Despite this, the committee felt able to make some recommendations by combining their clinical expertise and opinion with the approaches employed by the studies included in this review.

The committee stressed the importance of treating diverticular abscess with intravenous antibiotics as soon as possible due to the septic conditions and recommended that this was done in line with the existing NICE guideline on sepsis (NG51). Therefore, the committee recommended that those presenting with suspected diverticular abscess in primary care should be referred to secondary care immediately to receive intravenous antibiotics. The committee felt that intravenous antibiotics should be administered in secondary care before a CT scan was performed to avoid unnecessary delay in treating sepsis in these patients.

When discussing the approaches used by each of the included studies, the committee noted that the majority had used CT scan to confirm the presence of diverticular abscess and assess the characteristics of each abscess, which ultimately impacted upon the treatment that was selected. Based on their clinical expertise, the committee agreed that percutaneous drainage is not feasible in certain cases, such as in particularly small abscesses (< 3 cm) and where the procedure would involve passing through important structures that could become damaged as a result. For this reason, the committee considered that a CT scan could be useful for confirming and assessing abscesses and selecting the most appropriate treatment based on abscess characteristics. The committee suggested that abscesses < 3 cm in size may be treated with antibiotics alone initially, as this was the approach taken in most of the included studies and was consistent with the clinical expertise of the committee. For abscesses ≥ 3 cm, percutaneous drainage (if anatomically feasible) and surgery were considered as treatment options. The choice of treatment may be determined by factors such as the patient’s age, comorbidity and performance status. In cases where there is no improvement in condition or a deterioration following initial treatment, the committee felt that reimaging by CT should be considered in order to reassess the abscess characteristics and subsequent treatment options; for example, for abscesses < 3 cm that were originally treated with antibiotics only, a further CT may reveal an increase in size that makes percutaneous drainage feasible or may indicate that surgery is warranted.

The committee considered being able to recommend specific antibiotic regimens including co-amoxiclav or cefuroxime and metronidazole but evidence was limited and most trials used a variety of different antibiotics, with many suggesting the antibiotics were tailored to the sensitivities of the specimens sent. The committee also found it difficult to comment on the duration of therapy as there was very limited information in the studies included in the review. It was noted that evidence exists (but did not meet the evidence review protocol criteria) to suggest that if source control is achieved, a 4-7 day duration is sufficient however, if there is no source control the duration is difficult to determine and the duration suggested in the recommendations for abscesses < 3cm in size is taken from the wide variations in the quoted evidence.

In line with good anti-microbial stewardship the requirements for antibiotics should be reviewed when an abscess has not been confirmed.

1.7.2. Cost effectiveness and resource use

The clinical evidence was low quality and inconclusive and there was no cost effectiveness evidence. The committee were presented with the unit costs of antibiotics, percutaneous drainage and surgery. Recommendations were made, based on the expert opinion of the committee. The committee recommended antibiotics in line with the NICE Sepsis guideline (NG51). They also made a recommendation in favour of either percutaneous drainage or surgery, the cost of each is substantial – from NHS reference costs £4984 for the former and £7091-£8312 for the latter. CT was also recommended to inform procedure decisions. However, these patients will require an inpatient stay even in the absence of the procedure and the incremental cost is not clear. The clinical and cost effectiveness of the procedures is not known for this population and therefore the committee made a weak ‘consider’ recommendation. The recommendations do not represent a move away from current practice, which is variable.

1.7.3. Other factors the committee took into account

The committee noted that MRI or ultrasound (depending on local expertise) could be used if CT is contraindicated.

In people with a CT-confirmed diverticular abscess, reimaging may be considered if the condition does not improve clinically of if there is deterioration. This will guide the management strategy, for example if further surgery is required or if a previous collection that was not drainable percutaneously for example because it was too small is now drainable.

References

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13.: Kaiser AM, Jiang JK, Lake JP, Ault G, Artinyan A, Gonzalez-Ruiz C et al. The management of complicated diverticulitis and the role of computed tomography. American Journal of Gastroenterology. 2005; 100(4):910–7 [PubMed: 15784040]
14.: Knapp C, Brand M, Orkin B. Management of diverticular abscesses with nonsurgical drainage: Is there a need for interval resection? Diseases of the Colon and Rectum. 2015; 58(5):e153–e154
15.: Kumar RR, Kim JT, Haukoos JS, Macias LH, Dixon MR, Stamos MJ et al. Factors affecting the successful management of intra-abdominal abscesses with antibiotics and the need for percutaneous drainage. Diseases of the Colon and Rectum. 2006; 49(2):183–9 [PubMed: 16322960]
16.: Lamb MN, Kaiser AM. Elective resection versus observation after nonoperative management of complicated diverticulitis with abscess: a systematic review and meta-analysis. Diseases of the Colon and Rectum. 2014; 57(12):1430–40 [PubMed: 25380010]
17.: Macias LH, Haukoos JS, Dixon MR, Sorial E, Arnell TD, Stamos MJ et al. Diverticulitis: truly minimally invasive management. American Surgeon. 2004; 70(10):932–5 [PubMed: 15529855]
18.: McDermott FD, Collins D, Heeney A, Winter DC. Minimally invasive and surgical management strategies tailored to the severity of acute diverticulitis. British Journal of Surgery. 2014; 101(1):e90–9 [PubMed: 24258427]
19.: Mueller PR, Saini S, Wittenburg J, Simeone J, Hahn PF, Steiner E et al. Sigmoid diverticular abscesses: percutaneous drainage as an adjunct to surgical resection in 24 cases. Radiology. 1987; 164(2):321–5 [PubMed: 3602369]
20.: National Institute for Health and Care Excellence. Developing NICE guidelines: the manual. London. National Institute for Health and Care Excellence, 2014. Available from: http://www.nice.org.uk/article/PMG20/chapter/1%20Introduction%20and%20overview [PubMed: 26677490]
21.: Pappalardo G, Frattaroli FM, Coiro S, Spolentini D, Nunziale A, Favella L et al. Effectiveness of clinical guidelines in the management of acute sigmoid diverticulitis. Results of a prospective diagnostic and therapeutic clinical trial. Annali Italiani di Chirurgia. 2013; 84(2):171–7 [PubMed: 23697994]
22.: Roscoe J, Salem Hany T. Treatment outcomes following management of patients with diverticular abscess. Colorectal Disease. 2017; 19:(Suppl 4):59
23.: Schechter S, Eisenstat TE, Oliver GC, Rubin RJ, Salvati EP. Computerized tomographic scan-guided drainage of intra-abdominal abscesses. Preoperative and postoperative modalities in colon and rectal surgery. Diseases of the Colon and Rectum. 1994; 37(10):984–8 [PubMed: 7924719]
24.: Shuler FW, Newman CN, Angood PB, Tucker JG, Lucas GW. Nonoperative management for intra-abdominal abscesses. American Surgeon. 1996; 62(3):218–22 [PubMed: 8607582]
25.: Siewert B, Tye G, Kruskal J, Sosna J, Opelka F, Raptopoulos V et al. Impact of CT-guided drainage in the treatment of diverticular abscesses: size matters. American Journal of Roentgenology. 2006; 186(3):680–6 [PubMed: 16498095]
26.: Subhas G, Rana G, Bhullar J, Essad K, Mohey L, Mittal VK. Percutaneous drainage of a diverticular abscess should be limited to two attempts for a resilient diverticular abscess. American Surgeon. 2014; 80(7):635–9 [PubMed: 24987892]
27.: Suzuki K, Yamaguchi T, Iwashita Y, Yokoyama K, Fujioka M, Katayama N et al. Case series of iliopsoas abscesses treated at a university hospital in Japan: Epidemiology, clinical manifestations, diagnosis and treatment. Internal Medicine. 2015; 54(17):2147–2153 [PubMed: 26328638]
28.: Tou S, You K, Giuratrabocchetta S, Sullivan R, Denoya P, Bergamaschi R. Should elective resection follow nonoperative management of first episode of acute sigmoid diverticulitis with abscess/extraluminal air? A randomised controlled trial. Colorectal Disease. 2016; 18(S1):6
29.: Tudor RG, Farmakis N, Keighley MR. National audit of complicated diverticular disease: analysis of index cases. British Journal of Surgery. 1994; 81(5):730–2 [PubMed: 8044565]
30.: Villalon C, Aylwin P, Quezada F, Molina ME, Urrejola G, Miguieles R et al. Complicated acute diverticulitis with an abscess: Long-term results. Colorectal Disease. 2014; 16(S3):56

Appendices

Appendix A. Review protocols

Table 11Review protocol: Percutaneous drainage of abscesses

Field	Content
Review question	What is the clinical and cost effectiveness of percutaneous drainage versus resectional surgery for the management of abscesses?
Type of review question	intervention review A review of health economic evidence related to the same review question was conducted in parallel with this review. For details see the health economic review protocol for this NICE guideline.
Objective of the review	To determine whether percutaneous drainage is more clinically and cost effective than resection surgery for the management of abscesses
Eligibility criteria – population / disease / condition / issue / domain	Adults 18 years and over with acute diverticular abscesses
Eligibility criteria – intervention(s) / exposure(s) / prognostic factor(s)	Percutaneous drainage Antibiotics Surgery Combinations of treatments
Eligibility criteria – comparator(s) / control or reference (gold) standard	Compared to each other
Outcomes and prioritisation	Critical outcomes: Quality of life Mortality Morbidity Progression of disease recurrence of abscess Complications: infections abscesses perforation fistula stricture haemorrhage Re-hospitalisation Need for further surgery/percutaneous drain Anastomotic leak rate Stoma
Eligibility criteria – study design	Randomised controlled trials (RCTs), systematic reviews of RCTs. If no sufficient RCT evidence is available, search for observational studies
Other inclusion exclusion criteria	Exclusions: Children and young people aged 17 years and younger
Proposed sensitivity / subgroup analysis, or meta-regression	Subgroups: people of Asian family origin as they are known to develop right-sided diverticula immunocompromised population Aged <50 years, ≥50 years Abscess size <6 cm, ≥ 6 cm
Selection process – duplicate screening / selection / analysis	Studies are sifted by title and abstract. Potentially significant publications obtained in full text are then assessed against the inclusion criteria specified in this protocol.
Data management (software)	Pairwise meta-analyses performed using Cochrane Review Manager (RevMan5). GRADEpro used to assess the quality of evidence for each outcome Bibliographies, citations and study sifting managed using EndNote Data extractions performed using EviBase, a platform designed and maintained by the National Guideline Centre (NGC)
Information sources – databases and dates	Medline, Embase, The Cochrane Library
Identify if an update	Not applicable
Author contacts	https://www.nice.org.uk/guidance/conditions-and-diseases/digestive-tract-conditions/diverticular-disease
Highlight if amendment to previous protocol	For details please see section 4.5 of Developing NICE guidelines: the manual.
Search strategy – for one database	For details please see appendix B
Data collection process – forms / duplicate	A standardised evidence table format will be used, and published as appendix D of the evidence report.
Data items – define all variables to be collected	For details please see evidence tables in Appendix D (clinical evidence tables) or G (health economic evidence tables).
Methods for assessing bias at outcome / study level	Standard study checklists were used to critically appraise individual studies. For details please see section 6.2 of Developing NICE guidelines: the manual The risk of bias across all available evidence was evaluated for each outcome using an adaptation of the ‘Grading of Recommendations Assessment, Development and Evaluation (GRADE) toolbox’ developed by the international GRADE working group http://www.gradeworkinggroup.org/
Criteria for quantitative synthesis	For details please see section 6.4 of Developing NICE guidelines: the manual.
Methods for quantitative analysis – combining studies and exploring (in)consistency	For details please see the separate Methods report (Chapter R) for this guideline.
Meta-bias assessment – publication bias, selective reporting bias	For details please see section 6.2 of Developing NICE guidelines: the manual.
Confidence in cumulative evidence	For details please see sections 6.4 and 9.1 of Developing NICE guidelines: the manual.
Rationale / context – what is known	For details please see the introduction to the evidence review.
Describe contributions of authors and guarantor	A multidisciplinary committee developed the evidence review. The committee was convened by the National Guideline Centre (NGC) and chaired by James Dalrymple in line with section 3 of Developing NICE guidelines: the manual. Staff from NGC undertook systematic literature searches, appraised the evidence, conducted meta-analysis and cost-effectiveness analysis where appropriate, and drafted the evidence review in collaboration with the committee. For details please see Developing NICE guidelines: the manual.
Sources of funding / support	NGC is funded by NICE and hosted by the Royal College of Physicians.
Name of sponsor	NGC is funded by NICE and hosted by the Royal College of Physicians.
Roles of sponsor	NICE funds NGC to develop guidelines for those working in the NHS, public health and social care in England.
PROSPERO registration number	Not registered

Table 12Health economic review protocol

Review question	All questions – health economic evidence
Objectives	To identify health economic studies relevant to any of the review questions.
Search criteria	Populations, interventions and comparators must be as specified in the clinical review protocol above. Studies must be of a relevant health economic study design (cost–utility analysis, cost-effectiveness analysis, cost–benefit analysis, cost–consequences analysis, comparative cost analysis). Studies must not be a letter, editorial or commentary, or a review of health economic evaluations. (Recent reviews will be ordered although not reviewed. The bibliographies will be checked for relevant studies, which will then be ordered.) Unpublished reports will not be considered unless submitted as part of a call for evidence. Studies must be in English.
Search strategy	A health economic study search will be undertaken using population-specific terms and a health economic study filter – see appendix B below.
Review strategy	Studies not meeting any of the search criteria above will be excluded. Studies published before 2002, abstract-only studies and studies from non-OECD countries or the USA will also be excluded. Each remaining study will be assessed for applicability and methodological limitations using the NICE economic evaluation checklist which can be found in appendix H of Developing NICE guidelines: the manual (2014).²⁰ Inclusion and exclusion criteria If a study is rated as both ‘Directly applicable’ and with ‘Minor limitations’ then it will be included in the guideline. A health economic evidence table will be completed and it will be included in the health economic evidence profile. If a study is rated as either ‘Not applicable’ or with ‘Very serious limitations’ then it will usually be excluded from the guideline. If it is excluded then a health economic evidence table will not be completed and it will not be included in the health economic evidence profile. If a study is rated as ‘Partially applicable’, with ‘Potentially serious limitations’ or both then there is discretion over whether it should be included. Where there is discretion The health economist will make a decision based on the relative applicability and quality of the available evidence for that question, in discussion with the guideline committee if required. The ultimate aim is to include health economic studies that are helpful for decision-making in the context of the guideline and the current NHS setting. If several studies are considered of sufficiently high applicability and methodological quality that they could all be included, then the health economist, in discussion with the committee if required, may decide to include only the most applicable studies and to selectively exclude the remaining studies. All studies excluded on the basis of applicability or methodological limitations will be listed with explanation in the excluded health economic studies appendix below. The health economist will be guided by the following hierarchies. Setting: UK NHS (most applicable). OECD countries with predominantly public health insurance systems (for example, France, Germany, Sweden). OECD countries with predominantly private health insurance systems (for example, Switzerland). Studies set in non-OECD countries or in the USA will be excluded before being assessed for applicability and methodological limitations. Health economic study type: Cost–utility analysis (most applicable). Other type of full economic evaluation (cost–benefit analysis, cost-effectiveness analysis, cost–consequences analysis). Comparative cost analysis. Non-comparative cost analyses including cost-of-illness studies will be excluded before being assessed for applicability and methodological limitations. Year of analysis: The more recent the study, the more applicable it will be. Studies published in 2002 or later but that depend on unit costs and resource data entirely or predominantly from before 2002 will be rated as ‘Not applicable’. Studies published before 2002 will be excluded before being assessed for applicability and methodological limitations. Quality and relevance of effectiveness data used in the health economic analysis: The more closely the clinical effectiveness data used in the health economic analysis match with the outcomes of the studies included in the clinical review the more useful the analysis will be for decision-making in the guideline.

Appendix B. Literature search strategies

The literature searches for this review are detailed below and complied with the methodology outlined in Developing NICE guidelines: the manual 2014, updated 2017.

For more detailed information, please see the Methodology Review.

B.1. Clinical search literature search strategy

Searches were constructed using a PICO framework where population (P) terms were combined with Intervention (I) and in some cases Comparison (C) terms. Outcomes (O) are rarely used in search strategies for interventions as these concepts may not be well described in title, abstract or indexes and therefore difficult to retrieve. Search filters were applied to the search where appropriate.

Table 13Database date parameters and filters used

Database

Dates searched

Search filter used

Medline (OVID)

1946 – 13 November 2018

Exclusions

Randomised controlled trials

Systematic review studies

Observational studies

Embase (OVID)

1974 – 13 November 2018

Exclusions

Randomised controlled trials

Systematic review studies

Observational studies

The Cochrane Library (Wiley)

Cochrane Reviews to 2018 Issue 11 of 12

CENTRAL to 2018 Issue 11 of 12

DARE, and NHSEED to 2015 Issue 2 of 4

HTA to 2016 Issue 2 of 4

None

Table 14Medline (Ovid) search terms

1.	diverticul*.mp.
2.	limit 1 to English language
3.	letter/
4.	editorial/
5.	news/
6.	exp historical article/
7.	Anecdotes as Topic/
8.	comment/
9.	case report/
10.	(letter or comment*).ti.
11.	or/3-10
12.	randomized controlled trial/ or random*.ti,ab.
13.	11 not 12
14.	animals/ not humans/
15.	exp Animals, Laboratory/
16.	exp Animal Experimentation/
17.	exp Models, Animal/
18.	exp Rodentia/
19.	(rat or rats or mouse or mice).ti.
20.	or/13-19
21.	2 not 20
22.	randomized controlled trial.pt.
23.	controlled clinical trial.pt.
24.	randomi#ed.ti,ab.
25.	placebo.ab.
26.	randomly.ti,ab.
27.	Clinical Trials as topic.sh.
28.	trial.ti.
29.	or/22-28
30.	Meta-Analysis/
31.	exp Meta-Analysis as Topic/
32.	(meta analy* or metanaly* or metaanaly* or meta regression).ti,ab.
33.	((systematic* or evidence) adj3 (review or overview*)).ti,ab.
34.	(reference list* or bibliograph* or hand search* or manual search* or relevant journals).ab.
35.	(search strategy or search criteria or systematic search or study selection or data extraction).ab.
36.	(search* adj4 literature).ab.
37.	(medline or pubmed or cochrane or embase or psychlit or psyclit or psychinfo or psycinfo or cinahl or science citation index or bids or cancerlit).ab.
38.	cochrane.jw.
39.	((multiple treatment* or indirect or mixed) adj2 comparison*).ti,ab.
40.	or/50-59
41.	Epidemiologic studies/
42.	Observational study/
43.	exp Cohort studies/
44.	(cohort adj (study or studies or analys* or data)).ti,ab.
45.	((follow up or observational or uncontrolled or non randomi#ed or epidemiologic*) adj (study or studies or data)).ti,ab.
46.	((longitudinal or retrospective or prospective or cross sectional) and (study or studies or review or analys* or cohort* or data)).ti,ab.
47.	Controlled Before-After Studies/
48.	Historically Controlled Study/
49.	Interrupted Time Series Analysis/
50.	(before adj2 after adj2 (study or studies or data)).ti,ab.
51.	or/30-39
52.	exp case control study/
53.	case control*.ti,ab.
54.	or/41-42
55.	40 or 43
56.	Cross-sectional studies/
57.	(cross sectional and (study or studies or review or analys* or cohort* or data)).ti,ab.
58.	or/45-46
59.	40 or 47
60.	40 or 43 or 47
61.	21 and (29 or 40 or 60)

Table 15Embase (Ovid) search terms

1.	diverticul*.mp.
2.	limit 1 to English language
3.	letter.pt. or letter/
4.	note.pt.
5.	editorial.pt.
6.	case report/ or case study/
7.	(letter or comment*).ti.
8.	or/3-7
9.	randomized controlled trial/ or random*.ti,ab.
10.	8 not 9
11.	animal/ not human/
12.	nonhuman/
13.	exp Animal Experiment/
14.	exp Experimental Animal/
15.	animal model/
16.	exp Rodent/
17.	(rat or rats or mouse or mice).ti.
18.	or/10-17
19.	2 not 18
20.	random*.ti,ab.
21.	factorial*.ti,ab.
22.	(crossover* or cross over*).ti,ab.
23.	((doubl* or singl) adj blind).ti,ab.
24.	(assign* or allocat* or volunteer* or placebo*).ti,ab.
25.	crossover procedure/
26.	single blind procedure/
27.	randomized controlled trial/
28.	double blind procedure/
29.	or/20-28
30.	systematic review/
31.	meta-analysis/
32.	(meta analy* or metanaly* or metaanaly* or meta regression).ti,ab.
33.	((systematic* or evidence) adj3 (review or overview*)).ti,ab.
34.	(reference list* or bibliograph* or hand search* or manual search* or relevant journals).ab.
35.	(search strategy or search criteria or systematic search or study selection or data extraction).ab.
36.	(search* adj4 literature).ab.
37.	(medline or pubmed or cochrane or embase or psychlit or psyclit or psychinfo or psycinfo or cinahl or science citation index or bids or cancerlit).ab.
38.	cochrane.jw.
39.	((multiple treatment* or indirect or mixed) adj2 comparison*).ti,ab.
40.	or/30-39
41.	Clinical study/
42.	Observational study/
43.	family study/
44.	longitudinal study/
45.	retrospective study/
46.	prospective study/
47.	cohort analysis/
48.	follow-up/
49.	cohort*.ti,ab.
50.	48 and 49
51.	(cohort adj (study or studies or analys* or data)).ti,ab.
52.	((follow up or observational or uncontrolled or non randomi#ed or epidemiologic*) adj (study or studies or data)).ti,ab.
53.	((longitudinal or retrospective or prospective or cross sectional) and (study or studies or review or analys* or cohort* or data)).ti,ab.
54.	(before adj2 after adj2 (study or studies or data)).ti,ab.
55.	or/41-47,50-54
56.	exp case control study/
57.	case control*.ti,ab.
58.	or/56-57
59.	or 58
60.	cross-sectional study/
61.	(cross sectional and (study or studies or review or analys* or cohort* or data)).ti,ab.
62.	or/60-61
63.	or 62
64.	or 58 or 62
65.	and (29 or 40 or 64)

Table 16Cochrane Library (Wiley) search terms

#1.	diverticul*.mp.

B.2. Health Economics literature search strategy

Health economic evidence was identified by conducting a broad search relating to Diverticular Disease population in NHS Economic Evaluation Database (NHS EED – this ceased to be updated after March 2015) and the Health Technology Assessment database (HTA) with no date restrictions. NHS EED and HTA databases are hosted by the Centre for Research and Dissemination (CRD). Additional searches were run on Medline and Embase for health economics, economic modelling and quality of life studies.

Table 17Database date parameters and filters used

Database

Dates searched

Search filter used

Medline

1946 – 13 November 2018

Exclusions

Health economics studies

Health economics modelling studies

Quality of life studies

Embase

1974 – 13 November 2018

Exclusions

Health economics studies

Health economics modelling studies

Quality of life studies

Centre for Research and Dissemination (CRD)

HTA - Inception – 13 November 2018

NHSEED - Inception to March 2015

None

Table 18Medline (Ovid) search terms

1.	diverticul*.mp.
2.	limit 1 to English language
3.	letter/
4.	editorial/
5.	news/
6.	exp historical article/
7.	Anecdotes as Topic/
8.	comment/
9.	case report/
10.	(letter or comment*).ti.
11.	or/3-10
12.	randomized controlled trial/ or random*.ti,ab.
13.	11 not 12
14.	animals/ not humans/
15.	exp Animals, Laboratory/
16.	exp Animal Experimentation/
17.	exp Models, Animal/
18.	exp Rodentia/
19.	(rat or rats or mouse or mice).ti.
20.	or/13-19
21.	2 not 20
22.	Economics/
23.	Value of life/
24.	exp “Costs and Cost Analysis”/
25.	exp Economics, Hospital/
26.	exp Economics, Medical/
27.	Economics, Nursing/
28.	Economics, Pharmaceutical/
29.	exp “Fees and Charges”/
30.	exp Budgets/
31.	budget*.ti,ab.
32.	cost*.ti.
33.	(economic* or pharmaco?economic*).ti.
34.	(price* or pricing*).ti,ab.
35.	(cost* adj2 (effective* or utilit* or benefit* or minimi* or unit* or estimat* or variable*)).ab.
36.	(financ* or fee or fees).ti,ab.
37.	(value adj2 (money or monetary)).ti,ab.
38.	or/22-37
39.	exp models, economic/
40.	*Models, Theoretical/
41.	markov chains/
42.	monte carlo method/
43.	exp Decision Theory/
44.	(markov* or monte carlo).ti,ab.
45.	econom* model*.ti,ab.
46.	(decision* adj2 (tree* or analy* or model*)).ti,ab.
47.	Models, Organizational/
48.	*models, statistical/
49.	*logistic models/
50.	models, nursing/
51.	((organi?ation* or operation* or service* or concept) adj3 (model or map* or program* or simulation* or system* or analys*)).ti,ab.
52.	(econom* adj2 (theor* or system* or map* or evaluat*)).ti,ab.
53.	(SSM or SODA).ti,ab.
54.	(strateg* adj3 (option* or choice) adj3 (analys or decision*)).ti,ab.
55.	soft systems method*.ti,ab.
56.	(Meta-heuristic* or Metaheuristic*).ti,ab.
57.	(dynamic* adj2 (model* or system*)).ti,ab.
58.	(simulation adj3 (model* or discrete event* or agent)).ti,ab.
59.	(microsimulation* or “micro* simulation*”).ti,ab.
60.	((flow or core) adj2 model*).ti,ab.
61.	(data adj2 envelopment*).ti,ab.
62.	system* model*.ti,ab.
63.	or/41-64
64.	quality-adjusted life years/
65.	sickness impact profile/
66.	(quality adj2 (wellbeing or well being)).ti,ab.
67.	sickness impact profile.ti,ab.
68.	disability adjusted life.ti,ab.
69.	(qal* or qtime* or qwb* or daly*).ti,ab.
70.	(euroqol* or eq5d* or eq 5*).ti,ab.
71.	(qol* or hql* or hqol* or h qol* or hrqol* or hr qol*).ti,ab.
72.	(health utility* or utility score* or disutilit* or utility value*).ti,ab.
73.	(hui or hui1 or hui2 or hui3).ti,ab.
74.	(health* year* equivalent* or hye or hyes).ti,ab.
75.	discrete choice*.ti,ab.
76.	rosser.ti,ab.
77.	(willingness to pay or time tradeoff or time trade off or tto or standard gamble*).ti,ab.
78.	(sf36* or sf 36* or short form 36* or shortform 36* or shortform36*).ti,ab.
79.	(sf20 or sf 20 or short form 20 or shortform 20 or shortform20).ti,ab.
80.	(sf12* or sf 12* or short form 12* or shortform 12* or shortform12*).ti,ab.
81.	(sf8* or sf 8* or short form 8* or shortform 8* or shortform8*).ti,ab.
82.	(sf6* or sf 6* or short form 6* or shortform 6* or shortform6*).ti,ab.
83.	or/22-40
84.	21 and (38 or 63 or 83)

Table 19Embase (Ovid) search terms

1.	diverticul*.mp.
2.	limit 1 to English language
3.	letter.pt. or letter/
4.	note.pt.
5.	editorial.pt.
6.	case report/ or case study/
7.	(letter or comment*).ti.
8.	or/3-7
9.	randomized controlled trial/ or random*.ti,ab.
10.	8 not 9
11.	animal/ not human/
12.	nonhuman/
13.	exp Animal Experiment/
14.	exp Experimental Animal/
15.	animal model/
16.	exp Rodent/
17.	(rat or rats or mouse or mice).ti.
18.	or/10-17
19.	2 not 18
20.	Economics/
21.	Value of life/
22.	exp “Costs and Cost Analysis”/
23.	exp Economics, Hospital/
24.	exp Economics, Medical/
25.	Economics, Nursing/
26.	Economics, Pharmaceutical/
27.	exp “Fees and Charges”/
28.	exp Budgets/
29.	budget*.ti,ab.
30.	cost*.ti.
31.	(economic* or pharmaco?economic*).ti.
32.	(price* or pricing*).ti,ab.
33.	(cost* adj2 (effective* or utilit* or benefit* or minimi* or unit* or estimat* or variable*)).ab.
34.	(financ* or fee or fees).ti,ab.
35.	(value adj2 (money or monetary)).ti,ab.
36.	or/20-35
37.	statistical model/
38.	*theoretical model/
39.	nonbiological model/
40.	stochastic model/
41.	decision theory/
42.	decision tree/
43.	exp nursing theory/
44.	monte carlo method/
45.	(markov* or monte carlo).ti,ab.
46.	econom* model*.ti,ab.
47.	(decision* adj2 (tree* or analy* or model*)).ti,ab.
48.	((organi?ation* or operation* or service* or concept) adj3 (model or map* or program* or simulation* or system* or analys*)).ti,ab.
49.	(econom* adj2 (theor* or system* or map* or evaluat*)).ti,ab.
50.	(SSM or SODA).ti,ab.
51.	(strateg* adj3 (option* or choice) adj3 (analys or decision*)).ti,ab.
52.	soft systems method*.ti,ab.
53.	(Meta-heuristic* or Metaheuristic*).ti,ab.
54.	(dynamic* adj2 (model* or system*)).ti,ab.
55.	(simulation adj3 (model* or discrete event* or agent)).ti,ab.
56.	(microsimulation* or “micro* simulation*”).ti,ab.
57.	((flow or core) adj2 model*).ti,ab.
58.	(data adj2 envelopment*).ti,ab.
59.	system* model*.ti,ab.
60.	or/39-61
61.	quality adjusted life year/
62.	"quality of life index"/
63.	short form 12/ or short form 20/ or short form 36/ or short form 8/
64.	sickness impact profile/
65.	(quality adj2 (wellbeing or well being)).ti,ab.
66.	sickness impact profile.ti,ab.
67.	disability adjusted life.ti,ab.
68.	(qal* or qtime* or qwb* or daly*).ti,ab.
69.	(euroqol* or eq5d* or eq 5*).ti,ab.
70.	(qol* or hql* or hqol* or h qol* or hrqol* or hr qol*).ti,ab.
71.	(health utility* or utility score* or disutilit* or utility value*).ti,ab.
72.	(hui or hui1 or hui2 or hui3).ti,ab.
73.	(health* year* equivalent* or hye or hyes).ti,ab.
74.	discrete choice*.ti,ab.
75.	rosser.ti,ab.
76.	(willingness to pay or time tradeoff or time trade off or tto or standard gamble*).ti,ab.
77.	(sf36* or sf 36* or short form 36* or shortform 36* or shortform36*).ti,ab.
78.	(sf20 or sf 20 or short form 20 or shortform 20 or shortform20).ti,ab.
79.	(sf12* or sf 12* or short form 12* or shortform 12* or shortform12*).ti,ab.
80.	(sf8* or sf 8* or short form 8* or shortform 8* or shortform8*).ti,ab.
81.	(sf6* or sf 6* or short form 6* or shortform 6* or shortform6*).ti,ab.
82.	or/20-40
83.	19 and (36 or 60 or 82)

Table 20NHS EED and HTA (CRD) search terms

#1.	diverticul*

Appendix C. Clinical evidence selection

Figure 1Flow chart of clinical study selection for the review of percutaneous drainage of abscesses

Appendix D. Clinical evidence tables

Table 21. Clinical evidence tables (PDF, 420K)

Appendix E. Forest plots

E.1. Antibiotics vs. surgery

Figure 2Re-hospitalisation (readmission due to diverticulitis)

Figure 3Mortality within 30 days of admission

Figure 4Mortality within 30 days of discharge

Figure 5Re-hospitalisation (readmission, reasons other than diverticulitis)

E.2. Percutaneous drainage + antibiotics vs. antibiotics

Figure 6Re-hospitalisation (readmission due to diverticulitis)

Figure 7Need for further surgery/percutaneous drain

Figure 8Stoma creation

E.3. Percutaneous drainage + antibiotics vs. surgery

Figure 9Re-hospitalisation (readmission due to diverticulitis)

E.4. Percutaneous drainage + antibiotics + surgery vs. antibiotics + surgery

Figure 10Mortality

Figure 11Overall morbidity

Figure 12Overall stoma rate

E.5. Percutaneous drainage vs. antibiotics

Figure 13Mortality within 30 days of admission

Figure 14Mortality within 30 days of discharge

Figure 15Re-hospitalisation (readmission due to diverticulitis)

Figure 16Re-hospitalisation (readmission, reasons other than diverticulitis)

E.6. Percutaneous drainage vs. surgery

Figure 17Mortality within 30 days of admission

Figure 18Mortality within 30 days of discharge

Figure 19Re-hospitalisation (readmission due to diverticulitis)

Figure 20Re-hospitalisation (readmission, reasons other than diverticulitis)

Appendix F. GRADE tables

Table 22Clinical evidence profile: Antibiotics vs. surgery

Quality assessment							No of patients		Effect		Quality	Importance
No of studies	Design	Risk of bias	Inconsistency	Indirectness	Imprecision	Other considerations	Antibiotics	surgery	Relative (95% CI)	Absolute	Quality	Importance
Re-hospitalisation (readmission due to diverticulitis) (follow-up 1-110 months)
2	observational studies	very serious¹	no serious inconsistency	no serious indirectness	no serious imprecision	none	142/2475 (5.7%)	3.5%	RR 3.11 (1.49 to 6.49)	74 more per 1000 (from 17 more to 192 more)	⨁◯◯◯ VERY LOW	CRITICAL
Mortality within 30 days of admission (follow-up mean 30 days)
1	observational studies	very serious¹	no serious inconsistency	no serious indirectness	serious²	none	245/2432 (10.1%)	5.8%	RR 1.75 (1.02 to 3.01)	44 more per 1000 (from 1 more to 117 more)	⨁◯◯◯ VERY LOW	CRITICAL
Mortality within 30 days of discharge (follow-up mean 30 days)
1	observational studies	very serious¹	no serious inconsistency	no serious indirectness	serious²	none	48/2175 (2.2%)	4%	RR 0.56 (0.27 to 1.16)	18 fewer per 1000 (from 29 fewer to 6 more)	⨁◯◯◯ VERY LOW	CRITICAL
Re-hospitalisation (readmission, reasons other than diverticulitis) (follow-up mean 30 days)
1	observational studies	very serious¹	no serious inconsistency	no serious indirectness	serious²	none	403/2432 (16.6%)	24.3%	RR 0.68 (0.53 to 0.87)	78 fewer per 1000 (from 32 fewer to 114 fewer)	⨁◯◯◯ VERY LOW	CRITICAL

1: Downgraded by 1 increment if the majority of the evidence was at high risk of bias, and downgraded by 2 increments if the majority of the evidence was at very high risk of bias
2: Downgraded by 1 increment if the confidence interval crossed one MID or by 2 increments if the confidence interval crossed both MIDs

Table 23Clinical evidence profile: Percutaneous drainage + antibiotics vs. antibiotics

Quality assessment							No of patients		Effect		Quality	Importance
No of studies	Design	Risk of bias	Inconsistency	Indirectness	Imprecision	Other considerations	Percutaneous drainage + antibiotics	antibiotics	Relative (95% CI)	Absolute	Quality	Importance
Re-hospitalisation (readmission due to diverticulitis) (follow-up mean 46-110 months)
2	observational studies	very serious¹	serious²	no serious indirectness	very serious³	none	11/34 (32.4%)	22.6%	RR 1.56 (0.51 to 4.75)	127 more per 1000 (from 111 fewer to 848 more)	⨁◯◯◯ VERY LOW	CRITICAL
Need for further surgery/percutaneous drain (follow-up unclear)
3	observational studies	very serious¹	no serious inconsistency	no serious indirectness	serious³	none	42/62 (67.7%)	61.3%	OR 1.6 (0.85 to 3.01)	104 more per 1000 (from 39 fewer to 214 more)	⨁◯◯◯ VERY LOW	CRITICAL
Stoma creation (follow-up unclear)
2	observational studies	very serious¹	no serious inconsistency	no serious indirectness	serious³	none	16/58 (27.6%)	13.6%	RR 1.76 (0.99 to 3.14)	103 more per 1000 (from 1 fewer to 291 more)	⨁◯◯◯ VERY LOW	CRITICAL

1: Downgraded by 1 increment if the majority of the evidence was at high risk of bias, and downgraded by 2 increments if the majority of the evidence was at very high risk of bias
2: Downgraded by 1 increment because the point estimate varies widely between studies and I2=70%. Subgroup analysis could not be performed to explain heterogeneity due to there only being two studies, but the mean age in the two studies differed (≥50 years and <50 years).
3: Downgraded by 1 increment if the confidence interval crossed one MID or by 2 increments if the confidence interval crossed both MIDs

Table 24Clinical evidence profile: Percutaneous drainage + antibiotics vs. surgery

Quality assessment

No of patients

Effect

Quality

Importance

No of studies

Design

Risk of bias

Inconsistency

Indirectness

Imprecision

Other considerations

Percutaneous drainage + antibiotics

surgery

Relative (95% CI)

Absolute

Re-hospitalisation (readmission due to diverticulitis) (follow-up mean 110 months)

observational studies

very serious¹

no serious inconsistency

no serious indirectness

no serious imprecision

none

6/22

(27.3%)

4.8%

RR 5.73 (1.26 to 26.05)

227 more per 1000 (from 12 more to 1000 more)

⨁◯◯◯

VERY LOW

CRITICAL

1: Downgraded by 1 increment if the majority of the evidence was at high risk of bias, and downgraded by 2 increments if the majority of the evidence was at very high risk of bias

Table 25Clinical evidence profile: Percutaneous drainage + antibiotics + surgery vs. antibiotics + surgery

Quality assessment							No of patients		Effect		Quality	Importance
No of studies	Design	Risk of bias	Inconsistency	Indirectness	Imprecision	Other considerations	Percutaneous drainage + antibiotics + surgery	antibiotics + surgery	Relative (95% CI)	Absolute	Quality	Importance
Mortality (follow-up unclear)
1	observational studies	very serious¹	no serious inconsistency	no serious indirectness	very serious²	none	3/114 (2.6%)	0%	OR 3.66 (0.23 to 57.57)	30 more per 1000 (from 30 fewer to 80 more)³	⨁◯◯◯ VERY LOW	CRITICAL
Overall morbidity (follow-up unclear)
1	observational studies	very serious¹	no serious inconsistency	no serious indirectness	very serious²	none	42/114 (36.8%)	34.4%	RR 1.07 (0.63 to 1.83)	24 more per 1000 (from 127 fewer to 286 more)	⨁◯◯◯ VERY LOW	CRITICAL
Overall stoma rate (follow-up unclear)
1	observational studies	very serious¹	no serious inconsistency	no serious indirectness	serious²	none	51/114 (44.7%)	34.4%	RR 1.3 (0.77 to 2.19)	103 more per 1000 (from 79 fewer to 409 more)	⨁◯◯◯ VERY LOW	CRITICAL

1: Downgraded by 1 increment if the majority of the evidence was at high risk of bias, and downgraded by 2 increments if the majority of the evidence was at very high risk of bias
2: Downgraded by 1 increment if the confidence interval crossed one MID or by 2 increments if the confidence interval crossed both MIDs
3: Zero events in control group - risk difference entered manually for absolute effect.

Table 26Clinical evidence profile: Percutaneous drainage vs. antibiotics

Quality assessment							No of patients		Effect		Quality	Importance
No of studies	Design	Risk of bias	Inconsistency	Indirectness	Imprecision	Other considerations	Percutaneous drainage	antibiotics	Relative (95% CI)	Absolute	Quality	Importance
Mortality within 30 days of admission (follow-up mean 30 days)
1	observational studies	very serious¹	no serious inconsistency	no serious indirectness	no serious imprecision	none	17/490 (3.5%)	10.1%	RR 0.34 (0.21 to 0.56)	67 fewer per 1000 (from 44 fewer to 80 fewer)	⨁◯◯◯ VERY LOW	CRITICAL
Mortality within 30 days of discharge (follow-up mean 30 days)
1	observational studies	very serious¹	no serious inconsistency	no serious indirectness	serious²	none	14/464 (3%)	2.2%	RR 1.37 (0.76 to 2.46)	8 more per 1000 (from 5 fewer to 32 more)	⨁◯◯◯ VERY LOW	CRITICAL
Re-hospitalisation (readmission due to diverticulitis) (follow-up mean 30 days)
1	observational studies	very serious¹	no serious inconsistency	no serious indirectness	no serious imprecision	none	51/490 (10.4%)	5.3%	RR 1.96 (1.44 to 2.67)	51 more per 1000 (from 23 more to 89 more)	⨁◯◯◯ VERY LOW	CRITICAL
Re-hospitalisation (readmission, reasons other than diverticulitis) (follow-up mean 30 days)
1	observational studies	very serious¹	no serious inconsistency	no serious indirectness	serious²	none	108/490 (22%)	16.6%	RR 1.33 (1.1 to 1.61)	55 more per 1000 (from 17 more to 101 more)	⨁◯◯◯ VERY LOW	CRITICAL

1: Downgraded by 1 increment if the majority of the evidence was at high risk of bias, and downgraded by 2 increments if the majority of the evidence was at very high risk of bias
2: Downgraded by 1 increment if the confidence interval crossed one MID or by 2 increments if the confidence interval crossed both MIDs

Table 27Clinical evidence profile: Percutaneous drainage vs. surgery

Quality assessment							No of patients		Effect		Quality	Importance
No of studies	Design	Risk of bias	Inconsistency	Indirectness	Imprecision	Other considerations	Percutaneous drainage	surgery	Relative (95% CI)	Absolute	Quality	Importance
Mortality within 30 days of admission (follow-up mean 30 days)
1	observational studies	very serious¹	no serious inconsistency	no serious indirectness	serious²	none	17/490 (3.5%)	5.8%	RR 0.6 (0.3 to 1.22)	23 fewer per 1000 (from 41 fewer to 13 more)	⨁◯◯◯ VERY LOW	CRITICAL
Mortality within 30 days of discharge (follow-up mean 30 days)
1	observational studies	very serious¹	no serious inconsistency	no serious indirectness	very serious²	none	14/464 (3%)	4%	RR 0.76 (0.32 to 1.79)	10 fewer per 1000 (from 27 fewer to 32 more)	⨁◯◯◯ VERY LOW	CRITICAL
Re-hospitalisation (readmission due to diverticulitis) (follow-up mean 30 days)
1	observational studies	very serious¹	no serious inconsistency	no serious indirectness	no serious imprecision	none	51/490 (10.4%)	2.2%	RR 4.7 (1.9 to 11.63)	81 more per 1000 (from 20 more to 234 more)	⨁◯◯◯ VERY LOW	CRITICAL
Re-hospitalisation (readmission, reasons other than diverticulitis) (follow-up mean 30 days)
1	observational studies	very serious¹	no serious inconsistency	no serious indirectness	serious²	none	108/490 (22%)	24.3%	RR 0.91 (0.68 to 1.2)	22 fewer per 1000 (from 78 fewer to 49 more)	⨁◯◯◯ VERY LOW	CRITICAL

1: Downgraded by 1 increment if the majority of the evidence was at high risk of bias, and downgraded by 2 increments if the majority of the evidence was at very high risk of bias
2: Downgraded by 1 increment if the confidence interval crossed one MID or by 2 increments if the confidence interval crossed both MIDs

Appendix G. Health economic evidence selection

Figure 21Flow chart of health economic study selection for the guideline

* Non-relevant population, intervention, comparison, design or setting; non-English language

3.4 Non-surgical treatment of acute diverticulitis (Evidence review H)

3.6.1 Timing of surgery (Evidence review J)

3.6.2 Laparoscopic versus open resection (Evidence review K)

3.6.4 Primary versus secondary anastomosis (Evidence review M)

3.8 Laparoscopic lavage versus resection for perforated diverticulitis (Evidence review O)

3.9 Management of recurrent diverticulitis (Evidence review P)

Appendix H. Excluded studies

H.1. Excluded clinical studies

Table 28Studies excluded from the clinical review

Study	Exclusion reason
Ambrosetti 1992¹	Incorrect study design
Bernini 1997²	Inappropriate comparison
Dale 2011⁴	Abstract only
Detry 1992⁵	Incorrect interventions
Gaertner 2013⁷	Incorrect outcomes
Galbraith 2017⁸	Not review population. Incorrect interventions
Gregersen 2016¹¹	Systematic review: study designs inappropriate
Gregersen 2018¹⁰	Not review population
Hurme 1995¹²	Not review population
Knapp 2015¹⁴	Abstract only
Kumar 2006¹⁵	Incorrect study design
Lamb 2014¹⁶	Incorrect interventions
Macias 2004¹⁷	Incorrect study design
Mcdermott 2014¹⁸	Incorrect study design
Mueller 1987¹⁹	Not guideline condition. Incorrect study design
Pappalardo 2013²¹	Incorrect study design
Roscoe 2017²²	Abstract only
Schechter 1994²³	Not review population. Inappropriate comparison
Shuler 1996²⁴	Not review population. Incorrect study design
Suzuki 2015²⁷	Not review population. Incorrect study design
Tou 2016²⁸	Abstract only
Tudor 1994-1²⁹	Incorrect interventions
Villalon 2014³⁰	Abstract only

Tables

Table 1PICO characteristics of review question

Population	Adults 18 years and over with diverticular abscesses
Interventions	Percutaneous drainage Antibiotics Surgery Combinations of treatments
Comparisons	Compared to each other
Outcomes	Critical outcomes: Quality of life Mortality Morbidity Progression of disease Recurrence of abscess Complications (infections, abscesses, perforation, fistula, stricture, haemorrhage) Re-hospitalisation Need for further surgery/percutaneous drain Anastomotic leak rate Stoma
Study design	Randomised controlled trials (RCTs), systematic reviews of RCTs. If no RCT evidence is available, search for observational studies

Table 2Summary of studies included in the evidence review

Study

Intervention and comparison

Population

Outcomes

Patient selection for intervention

Comments

Buchwald 2017³

Non-randomised study

n=107

Retrospective

Univariate analysis

Antibiotics:

No details given concerning dose, type or duration.

Percutaneous drainage + antibiotics:

No details given concerning dose, type or duration of antibiotic treatment. No further details about percutaneous drainage.

Surgery:

Procedures included laparotomy and drainage, sigmoid resection with primary anastomosis and Hartmann’s procedure.

Adults 18 years and over with diverticular abscesses (Hinchey stages I and II).

Diagnosis in all patients by CT.

Clinical findings, blood tests, endoscopic and/or surgical finding and radiology also used for diagnosis.

Re-hospitalisation (readmission due to diverticulitis)

Treatment at discretion of surgeon.

Mean age:

Antibiotics, 60.5±17.6 years

Percutaneous drainage + antibiotics, 71.5±13.6 years

Surgery, 65.5±13.4 years

Mean abscess size differed between groups:

Antibiotics, 3.1±1.8 cm

Percutaneous drainage + antibiotics, 5.6±2.4 cm

Surgery, 4.6±1.6 cm

Localisation of abscesses differed between groups (proportion of pericolic, mesocolic and pelvic abscesses):

Antibiotics: 47%, 23% and 30%

Percutaneous drainage + antibiotics: 23%, 18% and 59%

Surgery: 40%, 29% and 31%

‘No differences in immunosuppression’ - no details for other comorbidities between groups.

Elagili 2015⁶

Non-randomised study

n=164

Retrospective

Univariate analysis

Percutaneous drainage + antibiotics + surgery:

Percutaneous drainage performed with wide-spectrum IV antibiotics progressively switched to oral formulation at surgeon discretion. Total treatment course of 1-3 weeks.

Followed by emergency or elective surgery.

Antibiotics + surgery:

Wide-spectrum IV antibiotics progressively switched to oral formulation at surgeon discretion. Total treatment course of 1-3 weeks.

Followed by emergency or elective surgery.

Adults 18 years and over with an abscess >3 cm associated with sigmoid diverticulitis.

Diagnosis by CT.

Mortality

Overall morbidity

Overall stoma rate

Treatment at discretion of surgeon.

Median age: 56.5 (25-85) years vs. 55.5 (36-82) years

Median abscess size differed between groups: 4 (3-18.5) cm

Vs. 6.7 (3-15) cm

Higher proportion of ASA 3 and lower proportion of ASA 2 in percutaneous drainage + antibiotics + surgery group.

Charlson comorbidity index similar between groups: 2.1 vs. 2.2

Gregersen 2016⁹

Non-randomised study

n=3148

Retrospective

Univariate analysis

Antibiotics:

Details of antibiotic treatment could not be obtained from the registers used. This group may consist of those that received antibiotics or no treatment at all.

Percutaneous drainage:

Non-surgical abscess drainage with a transabdominal, transvaginal or transrectal approach.

Surgery:

Includes those that underwent colonic surgery or surgical abscess drainage during admission.

Adults 18 years and over admitted for Hinchey Ib-II diverticulitis (complicated by abscess).

Method of diagnosis not specified.

Mortality within 30 days of admission

Mortality within 30 days of discharge

Re-hospitalisation (readmission due to diverticulitis)

Re-hospitalisation (readmission, reasons other than diverticulitis)

Retrospective review of patient records – treatment selected by clinician

Mean age:

Antibiotics: 65.6±15.4 years

Percutaneous drainage: 63.5±14.9 years

Surgery: 63.7±15.0 years

Details of abscess size in each group not available.

Previous episodes of complicated diverticulitis:

Antibiotics: 11.4%

Percutaneous drainage: 3.5%

Surgery: 0%

Proportion of patients with comorbidity similar between groups (47%, 50.2% and 54.9%).

Kaiser 2005¹³

Non-randomised study

n=511

Retrospective

Univariate analysis

Percutaneous drainage + antibiotics:

All patients started on broad-spectrum antibiotics with coverage for gram-negative and anaerobic bacteria. Percutaneous drainage performed where abscess was a sufficient size and in favourable location for drainage.

Antibiotics:

All patients started on broad-spectrum antibiotics with coverage for gram-negative and anaerobic bacteria.

Adults 18 years and over with diverticulitis complicated by abscess (modified Hinchey stages Ib and II).

Diagnosis confirmed by CT scan.

Re-hospitalisation (readmission due to diverticulitis)

Need for further surgery/percutaneous drain

Stoma creation

Assignment of patients to groups was dependent on whether each abscess was considered to be suitable for percutaneous drainage in terms of size and location.

Age not reported separately for each intervention.

Mean abscess size: 7.1±1.9 cm vs. 3.6±2.3 cm

Lower proportion of stage Ib and higher proportion of stage II abscesses in the percutaneous drainage + antibiotics group.

No details concerning comorbidity in each group.

Data extracted only for abscess subgroup within a larger cohort that this study covers.

Siewert 2006²⁵

Non-randomised study

n=181

Retrospective

Univariate analysis

Percutaneous drainage + antibiotics:

CT-guided percutaneous drainage performed within 24 h of admission. No details concerning type, dose or duration of antibiotic treatment.

Antibiotics:

No details concerning type, dose or duration of antibiotic treatment.

Adults 18 years and over with diverticulitis complicated by abscess.

Diagnosis confirmed by CT scan.

Need for further surgery/percutaneous drain

Assignment of patients to group was based on patient condition – all of those in the antibiotic group had abscesses where percutaneous drainage was considered to be unfeasible as they could not be reached percutaneously without traversing vital structures.

Age not reported separately for each intervention.

Mean abscess size: 5.9 cm vs. 3.8 cm.

No details concerning comorbidity in each group.

This study contained results for small and large (<3 cm and ≥3 cm) abscesses, but data was extracted for the large subgroup only, as all of the small abscesses were treated by the same intervention.

Subhas 2014²⁶

Non-randomised study

n=117

Retrospective

Univariate analysis

Percutaneous drainage + antibiotics:

Treatment with parenteral antibiotics against Gram-negative and anaerobic bacteria while in hospital. Abscesses sent for culture and sensitivity to guide choice of antibiotics. Drainage included simple aspiration to the placement of drains. Includes those that underwent one or more drainages.

Antibiotics:

Treatment with parenteral antibiotics against Gram-negative and anaerobic bacteria while in hospital. Abscesses sent for culture and sensitivity to guide choice of antibiotics.

Adults 18 years and over with CT scan-proven left-sided diverticular abscess treated as inpatients

Diagnosis confirmed by CT scan.

Need for further surgery/percutaneous drain

Stoma creation

Assignment of patients to group was based on patient condition – those in the antibiotics group were those with abscesses <2 cm or abscesses that were considered to be unsafe for percutaneous drainage.

Mean age: 61 (26-91) years vs. 62 (25-92) years.

Mean maximum size of abscess cavity: 6 (2-19.1) cm vs. 3 (0.7-8) cm.

No details concerning comorbidity in each group.

This study reported outcomes separately for patients that received various numbers of drainages (0, 1, 2 or ≥3) – data for 1, 2 and ≥3 drainages were combined and compared with those that did not receive percutaneous drainage at all.

Table 3Clinical evidence summary: Antibiotics vs. surgery

Outcomes	No of Participants (studies) Follow up	Quality of the evidence (GRADE)	Relative effect (95% CI)	Anticipated absolute effects
Outcomes	No of Participants (studies) Follow up	Quality of the evidence (GRADE)	Relative effect (95% CI)	Risk with surgery	Risk difference with Antibiotics (95% CI)
Re-hospitalisation (readmission due to diverticulitis)	2743 (2 studies) 1-110 months	⊕⊝⊝⊝ VERY LOW^a due to risk of bias	RR 3.11 (1.49 to 6.49)	Moderate
Re-hospitalisation (readmission due to diverticulitis)	2743 (2 studies) 1-110 months	⊕⊝⊝⊝ VERY LOW^a due to risk of bias	RR 3.11 (1.49 to 6.49)	35 per 1000	74 more per 1000 (from 17 more to 192 more)
Mortality within 30 days of admission	2658 (1 study) 30 days	⊕⊝⊝⊝ VERY LOW^a^,^b due to risk of bias, imprecision	RR 1.75 (1.02 to 3.01)	Moderate
Mortality within 30 days of admission	2658 (1 study) 30 days	⊕⊝⊝⊝ VERY LOW^a^,^b due to risk of bias, imprecision	RR 1.75 (1.02 to 3.01)	58 per 1000	44 more per 1000 (from 1 more to 117 more)
Mortality within 30 days of discharge	2377 (1 study) 30 days	⊕⊝⊝⊝ VERY LOW^a^,^b due to risk of bias, imprecision	RR 0.56 (0.27 to 1.16)	Moderate
Mortality within 30 days of discharge	2377 (1 study) 30 days	⊕⊝⊝⊝ VERY LOW^a^,^b due to risk of bias, imprecision	RR 0.56 (0.27 to 1.16)	40 per 1000	18 fewer per 1000 (from 29 fewer to 6 more)
Re-hospitalisation (readmission, reasons other than diverticulitis)	2658 (1 study) 30 days	⊕⊝⊝⊝ VERY LOW^a^,^b due to risk of bias, imprecision	RR 0.68 (0.53 to 0.87)	Moderate
	2658 (1 study) 30 days	⊕⊝⊝⊝ VERY LOW^a^,^b due to risk of bias, imprecision	RR 0.68 (0.53 to 0.87)	243 per 1000	78 fewer per 1000 (from 32 fewer to 114 fewer)

a: Downgraded by 1 increment if the majority of the evidence was at high risk of bias, and downgraded by 2 increments if the majority of the evidence was at very high risk of bias
b: Downgraded by 1 increment if the confidence interval crossed one MID or by 2 increments if the confidence interval crossed both MIDs

Table 4Clinical evidence summary: Percutaneous drainage + antibiotics vs. antibiotics

Outcomes	No of Participants (studies) Follow up	Quality of the evidence (GRADE)	Relative effect (95% CI)	Anticipated absolute effects
Outcomes	No of Participants (studies) Follow up	Quality of the evidence (GRADE)	Relative effect (95% CI)	Risk with antibiotics	Risk difference with Percutaneous drainage + antibiotics (95% CI)
Re-hospitalisation (readmission due to diverticulitis)	137 (2 studies) 46-110 months	⊕⊝⊝⊝ VERY LOW^a^,^b^,^c due to risk of bias, inconsistency, imprecision	RR 1.56 (0.51 to 4.75)	Moderate
Re-hospitalisation (readmission due to diverticulitis)	137 (2 studies) 46-110 months		RR 1.56 (0.51 to 4.75)	226 per 1000	127 more per 1000 (from 111 fewer to 848 more)
Need for further surgery/percutaneous drain	224 (3 studies) unclear	⊕⊝⊝⊝ VERY LOW^a^,^c due to risk of bias, imprecision	OR 1.6 (0.85 to 3.01)	Moderate
Need for further surgery/percutaneous drain	224 (3 studies) unclear	⊕⊝⊝⊝ VERY LOW^a^,^c due to risk of bias, imprecision	OR 1.6 (0.85 to 3.01)	613 per 1000	104 more per 1000 (from 39 fewer to 214 more)
Stoma creation	216 (2 studies) unclear	⊕⊝⊝⊝ VERY LOW^a^,^c due to risk of bias, imprecision	RR 1.76 (0.99 to 3.14)	Moderate
Stoma creation	216 (2 studies) unclear	⊕⊝⊝⊝ VERY LOW^a^,^c due to risk of bias, imprecision	RR 1.76 (0.99 to 3.14)	136 per 1000	103 more per 1000 (from 1 fewer to 291 more)

a: Downgraded by 1 increment if the majority of the evidence was at high risk of bias, and downgraded by 2 increments if the majority of the evidence was at very high risk of bias
b: Downgraded by 1 increment because the point estimate varies widely between studies and I2=70%. Subgroup analysis could not be performed to explain heterogeneity due to there only being two studies, but the mean age in the two studies differed (≥50 years and <50 years).
c: Downgraded by 1 increment if the confidence interval crossed one MID or by 2 increments if the confidence interval crossed both MIDs

Table 5Clinical evidence summary: Percutaneous drainage + antibiotics vs. surgery

Outcomes

No of Participants (studies) Follow up

Quality of the evidence (GRADE)

Relative effect (95% CI)

Anticipated absolute effects

Risk with surgery

Risk difference with Percutaneous drainage + antibiotics (95% CI)

Re-hospitalisation (readmission due to diverticulitis)

(1 study)

110 months

⊕⊝⊝⊝

VERY LOW^a

due to risk of bias

RR 5.73 (1.26 to 26.05)

Moderate

48 per 1000

227 more per 1000

(from 12 more to 1000 more)

a: Downgraded by 1 increment if the majority of the evidence was at high risk of bias, and downgraded by 2 increments if the majority of the evidence was at very high risk of bias

Table 6Clinical evidence summary: Percutaneous drainage + antibiotics + surgery vs. antibiotics + surgery

Outcomes	No of Participants (studies) Follow up	Quality of the evidence (GRADE)	Relative effect (95% CI)	Anticipated absolute effects
Outcomes	No of Participants (studies) Follow up	Quality of the evidence (GRADE)	Relative effect (95% CI)	Risk with antibiotics + surgery	Risk difference with Percutaneous drainage + antibiotics + surgery (95% CI)
Mortality	146 (1 study) unclear	⊕⊝⊝⊝ VERY LOW^a^,^b due to risk of bias, imprecision	OR 3.66 (0.23 to 57.57)	Moderate
Mortality	146 (1 study) unclear	⊕⊝⊝⊝ VERY LOW^a^,^b due to risk of bias, imprecision	OR 3.66 (0.23 to 57.57)	0 per 1000	30 more per 1000 (from 30 fewer to 80 more)^c
Overall morbidity	146 (1 study) unclear	⊕⊝⊝⊝ VERY LOW^a^,^b due to risk of bias, imprecision	RR 1.07 (0.63 to 1.83)	Moderate
Overall morbidity	146 (1 study) unclear	⊕⊝⊝⊝ VERY LOW^a^,^b due to risk of bias, imprecision	RR 1.07 (0.63 to 1.83)	344 per 1000	24 more per 1000 (from 127 fewer to 286 more)
Overall stoma rate	146 (1 study) unclear	⊕⊝⊝⊝ VERY LOW^a^,^b due to risk of bias, imprecision	RR 1.3 (0.77 to 2.19)	Moderate
Overall stoma rate	146 (1 study) unclear	⊕⊝⊝⊝ VERY LOW^a^,^b due to risk of bias, imprecision	RR 1.3 (0.77 to 2.19)	344 per 1000	103 more per 1000 (from 79 fewer to 409 more)

a: Downgraded by 1 increment if the majority of the evidence was at high risk of bias, and downgraded by 2 increments if the majority of the evidence was at very high risk of bias
b: Downgraded by 1 increment if the confidence interval crossed one MID or by 2 increments if the confidence interval crossed both MIDs
c: Zero events in control group - risk difference entered manually for absolute effect.

Table 7Clinical evidence summary: Percutaneous drainage vs. antibiotics

Outcomes	No of Participants (studies) Follow up	Quality of the evidence (GRADE)	Relative effect (95% CI)	Anticipated absolute effects
Outcomes	No of Participants (studies) Follow up	Quality of the evidence (GRADE)	Relative effect (95% CI)	Risk with antibiotics	Risk difference with Percutaneous drainage (95% CI)
Mortality within 30 days of admission	2922 (1 study) 30 days	⊕⊝⊝⊝ VERY LOW^a due to risk of bias	RR 0.34 (0.21 to 0.56)	Moderate
Mortality within 30 days of admission	2922 (1 study) 30 days	⊕⊝⊝⊝ VERY LOW^a due to risk of bias	RR 0.34 (0.21 to 0.56)	101 per 1000	67 fewer per 1000 (from 44 fewer to 80 fewer)
Mortality within 30 days of discharge	2639 (1 study) 30 days	⊕⊝⊝⊝ VERY LOW^a^,^b due to risk of bias, imprecision	RR 1.37 (0.76 to 2.46)	Moderate
Mortality within 30 days of discharge	2639 (1 study) 30 days	⊕⊝⊝⊝ VERY LOW^a^,^b due to risk of bias, imprecision	RR 1.37 (0.76 to 2.46)	22 per 1000	8 more per 1000 (from 5 fewer to 32 more)
Re-hospitalisation (readmission due to diverticulitis)	2922 (1 study) 30 days	⊕⊝⊝⊝ VERY LOW^a due to risk of bias	RR 1.96 (1.44 to 2.67)	Moderate
Re-hospitalisation (readmission due to diverticulitis)	2922 (1 study) 30 days	⊕⊝⊝⊝ VERY LOW^a due to risk of bias	RR 1.96 (1.44 to 2.67)	53 per 1000	51 more per 1000 (from 23 more to 89 more)
Re-hospitalisation (readmission, reasons other than diverticulitis)	2922 (1 study) 30 days	⊕⊝⊝⊝ VERY LOW^a^,^b due to risk of bias, imprecision	RR 1.33 (1.1 to 1.61)	Moderate
	2922 (1 study) 30 days	⊕⊝⊝⊝ VERY LOW^a^,^b due to risk of bias, imprecision	RR 1.33 (1.1 to 1.61)	166 per 1000	55 more per 1000 (from 17 more to 101 more)

a: Downgraded by 1 increment if the majority of the evidence was at high risk of bias, and downgraded by 2 increments if the majority of the evidence was at very high risk of bias
b: Downgraded by 1 increment if the confidence interval crossed one MID or by 2 increments if the confidence interval crossed both MIDs

Table 8Clinical evidence summary: Percutaneous drainage vs. surgery

Outcomes	No of Participants (studies) Follow up	Quality of the evidence (GRADE)	Relative effect (95% CI)	Anticipated absolute effects
Outcomes	No of Participants (studies) Follow up	Quality of the evidence (GRADE)	Relative effect (95% CI)	Risk with surgery	Risk difference with Percutaneous drainage (95% CI)
Mortality within 30 days of admission	716 (1 study) 30 days	⊕⊝⊝⊝ VERY LOW^a^,^b due to risk of bias, imprecision	RR 0.6 (0.3 to 1.22)	Moderate
Mortality within 30 days of admission	716 (1 study) 30 days	⊕⊝⊝⊝ VERY LOW^a^,^b due to risk of bias, imprecision	RR 0.6 (0.3 to 1.22)	58 per 1000	23 fewer per 1000 (from 41 fewer to 13 more)
Mortality within 30 days of discharge	666 (1 study) 30 days	⊕⊝⊝⊝ VERY LOW^a^,^b due to risk of bias, imprecision	RR 0.76 (0.32 to 1.79)	Moderate
Mortality within 30 days of discharge	666 (1 study) 30 days	⊕⊝⊝⊝ VERY LOW^a^,^b due to risk of bias, imprecision	RR 0.76 (0.32 to 1.79)	40 per 1000	10 fewer per 1000 (from 27 fewer to 32 more)
Re-hospitalisation (readmission due to diverticulitis)	716 (1 study) 30 days	⊕⊝⊝⊝ VERY LOW^a due to risk of bias	RR 4.7 (1.9 to 11.63)	Moderate
Re-hospitalisation (readmission due to diverticulitis)	716 (1 study) 30 days	⊕⊝⊝⊝ VERY LOW^a due to risk of bias	RR 4.7 (1.9 to 11.63)	22 per 1000	81 more per 1000 (from 20 more to 234 more)
Re-hospitalisation (readmission, reasons other than diverticulitis)	716 (1 study) 30 days	⊕⊝⊝⊝ VERY LOW^a^,^b due to risk of bias, imprecision	RR 0.91 (0.68 to 1.2)	Moderate
	716 (1 study) 30 days	⊕⊝⊝⊝ VERY LOW^a^,^b due to risk of bias, imprecision	RR 0.91 (0.68 to 1.2)	243 per 1000	22 fewer per 1000 (from 78 fewer to 49 more)

a: Downgraded by 1 increment if the majority of the evidence was at high risk of bias, and downgraded by 2 increments if the majority of the evidence was at very high risk of bias
b: Downgraded by 1 increment if the confidence interval crossed one MID or by 2 increments if the confidence interval crossed both MIDs

Table 9NHS costs of non-elective procedures

Procedure

Currency Description

Unit Cost

Average Length of Stay

Source

Image controlled percutaneous drainage of abdominal abscess NEC

YF04 Percutaneous Single Drainage of Abdominal Abscess, inclusive of excess bed days, weighted for complications and co morbidities for HRG codes YF04A, YF04B and YF04C; as recorded for Non-Elective Inpatients

£4,984

10.6 days

NHS Reference Costs 2016-2017

Sigmoid colectomy and anastomosis

FF33 Distal Colon Procedures, 19 years and over, inclusive of non-elective short stay and non-elective long stay with excess bed days, weighted for complications and co morbidities for HRG codes: FF33A and FF33B; as recorded for Non-Elective Inpatients

£7,091

9.0 days

NHS Reference Costs 2016-2017

Sigmoid colectomy and ileostomy HFQ

Sigmoid colectomy and exteriorisation of bowel NEC

FF31 Complex Large Intestine Procedures, 19 years and over, inclusive of non-elective short stay and non-elective long stay with excess bed days, weighted for complications and co morbidities for HRG codes: FF31A, FF31B, FF31C and FF31D; as recorded for Non-Elective Inpatients

£8,312

11.0 days

NHS Reference Costs 2016-2017

Table 10UK cost of antibiotics

Drug	Assumed daily dose [BNF]^(a)	Cost per unit (£)	Cost per course (£)^(b)	Source
Intravenous
Co-Amoxiclav 1000mg/200mg powder for solution for injection	1000mg/ 200mg every 8 hours by intravenous infusion	£1.06	£6.36^(c) - £31.80^(d)	BNF NHS Indicative price
Ciprofloxacin 400mg/200ml solution for infusion bottles	2x 400mg daily by intravenous infusion	£2.08	£29.12^(e)	BNF NHS Indicative price
Metronidazole 500mg/100ml infusion 100ml bags	3 × 500mg daily by intravenous infusion	£3.19	£66.99^(e)	BNF NHS Indicative price
Ertapenem sodium 1g powder for solution for infusion vials	1g daily by intravenous infusion	£31.86	£127.44^(f)-£223.02^(e)	BNF NHS Indicative Price
Piperacillin 2g/Tazobactam 250mg powder for solution for injection vials	4.5g every 8 hours by intravenous infusion	£7.65	£321.30^(e)	NHS Drug Tariff
Cefuroxime 750mg powder for solution for injection vials	1.5g every 8 hours; by intravenous infusion	£2.52	£45.36^(g)	BNF NHS Indicative Price
Amoxicillin 500mg powder for solution for injection vials	3x 500mg daily by intravenous infusion	£0.55	£11.51^(f)	NHS Drug Tariff
Gentamicin 240mg/80ml infusion bags	5-7mg/kg daily	£6.13	£85.80^(f)	NHS Drug Tariff
Oral
Co-Amoxiclav 500mg/125mg tablets (oral)	3 × 500mg/125mg tablets daily	£0.08	£2.36^(d)	NHS Drug Tariff
Ciprofloxacin 500 mg tablets (oral)	2x 500mg tablets daily	£0.08	£1.15^(e)	NHS Drug Tariff
Metronidazole 400mg tablets (oral)	3 × 400mg daily	£0.25	£5.18^(e)	NHS Drug Tariff
Cefadroxil 500mg capsules (oral)	2 × 500g capsules daily	£1.12	£15.67^(e)	NHS Drug Tariff
Cefuroxime 125mg tablets	4 × 125mg tablets daily	£0.33	£3.91^(g)	NHS Drug Tariff
Trimethoprim 200mg tablets	2x 200mg daily	£0.07	£0.93^(f)	NHS Drug Tariff
Cephalexin 500mg tablets	500mg every 8 hours	£0.08	£1.71^(e)	NHS Drug Tariff

(a): Dosages for adults, British National Formulary
(b): Depending on number of units taken
(c): Cost when dose taken for 2 days
(d): Cost when dose taken for 10 days
(e): Cost when dose taken for 7 days
(f): Cost when dose taken for 4 days
(g): Cost when dose taken for 3 days

Final

Intervention evidence review

This evidence review was developed by the National Guideline Centre

Disclaimer: The recommendations in this guideline represent the view of NICE, arrived at after careful consideration of the evidence available. When exercising their judgement, professionals are expected to take this guideline fully into account, alongside the individual needs, preferences and values of their patients or service users. The recommendations in this guideline are not mandatory and the guideline does not override the responsibility of healthcare professionals to make decisions appropriate to the circumstances of the individual patient, in consultation with the patient and, where appropriate, their carer or guardian.

Local commissioners and providers have a responsibility to enable the guideline to be applied when individual health professionals and their patients or service users wish to use it. They should do so in the context of local and national priorities for funding and developing services, and in light of their duties to have due regard to the need to eliminate unlawful discrimination, to advance equality of opportunity and to reduce health inequalities. Nothing in this guideline should be interpreted in a way that would be inconsistent with compliance with those duties.

NICE guidelines cover health and care in England. Decisions on how they apply in other UK countries are made by ministers in the Welsh Government, Scottish Government, and Northern Ireland Executive. All NICE guidance is subject to regular review and may be updated or withdrawn.

Bookshelf ID: NBK558093PMID: 32525634