A type of cirrhosis characterized by the presence of small regenerative nodules.

Hepatocellular carcinoma is the major histologic type of malignant primary liver neoplasm. It is the fifth most common cancer and the third most common cause of death from cancer worldwide. The major risk factors for HCC are chronic hepatitis B virus (HBV) infection, chronic hepatitis C virus (HCV) infection, prolonged dietary aflatoxin exposure, alcoholic cirrhosis, and cirrhosis due to other causes. Hepatoblastomas comprise 1 to 2% of all malignant neoplasms of childhood, most often occurring in children under 3 years of age. Hepatoblastomas are thought to be derived from undifferentiated hepatocytes (Taniguchi et al., 2002).

Wilson disease is a disorder of copper metabolism that, when untreated, can present with hepatic, neurologic, or psychiatric disturbances – or a combination of these – in individuals ages three years to older than 70 years. Manifestations in untreated individuals vary among and within families. Liver disease can include recurrent jaundice, simple acute self-limited hepatitis-like illness, autoimmune-type hepatitis, fulminant hepatic failure, or chronic liver disease. Neurologic presentations can include dysarthria, movement disorders (tremors, involuntary movements, chorea, choreoathetosis), dystonia (mask-like facies, rigidity, gait disturbance, pseudobulbar involvement), dysautonomia, seizures, sleep disorders, or insomnia. Psychiatric disturbances can include depression, bipolar disorder / bipolar spectrum disorder, neurotic behaviors, personality changes, or psychosis. Other multisystem involvement can include the eye (Kayser-Fleischer rings), hemolytic anemia, the kidneys, the endocrine glands, and the heart.

An acute porphyria attack is characterized by a urine porphobilinogen (PBG)-to-creatinine ratio =10 times the upper limit of normal (ULN) and the presence of =2 porphyria manifestations (involving the visceral, peripheral, autonomic, and/or central nervous systems) persisting for >24 hours in the absence of other likely explanations. Onset of acute attacks typically occurs in the second or third decade of life. Acute attacks are more common in women than men. Although attacks in most individuals are typically caused by exposure to certain endogenous or exogenous factors, often no precipitating factor can be identified. The course of acute porphyria attacks is highly variable in an individual and between individuals. Recovery from acute porphyria attacks may occur within days; however, recovery from severe attacks that are not promptly recognized and treated may take weeks or months. The five categories of acute intermittent porphyria (AIP), caused by a heterozygous HMBS pathogenic variant, are based on the urine PBG-to-creatinine ratio and occurrence of acute attacks. Active (symptomatic) AIP: An individual who has experienced at least one acute attack within the last two years. Symptomatic high excreter: Urine PBG-to-creatinine ratio =4 times ULN and no acute attacks in the last two years but chronic long-standing manifestations of acute porphyria. Asymptomatic high excreter: Urine PBG-to-creatinine ratio =4 times ULN and no acute attacks in the last two years and no porphyria-related manifestations. Asymptomatic AIP: Urine PBG-to-creatinine ratio <4 times ULN and no acute attacks in the last two years but has had =1 acute attack in the past. Latent (inactive) AIP: Urine PBG-to-creatinine ratio <4 times ULN and no acute porphyria-related manifestations to date.

X-linked agammaglobulinemia (XLA) is characterized by recurrent bacterial infections in affected males in the first two years of life. Recurrent otitis is the most common infection prior to diagnosis. Conjunctivitis, sinopulmonary infections, diarrhea, and skin infections are also frequently seen. Approximately 60% of individuals with XLA are recognized as having immunodeficiency when they develop a severe, life-threatening infection such as pneumonia, empyema, meningitis, sepsis, cellulitis, or septic arthritis. S pneumoniae and H influenzae are the most common organisms found prior to diagnosis and may continue to cause sinusitis and otitis after diagnosis and the initiation of gammaglobulin substitution therapy. Severe, difficult-to-treat enteroviral infections (often manifesting as dermatomyositis or chronic meningoencephalitis) can be prevented by this treatment. The prognosis for individuals with XLA has improved markedly in the last 25 years as a result of earlier diagnosis, the development of preparations of gammaglobulin that allow normal concentrations of serum immunoglobulin G to be achieved, and more liberal use of antibiotics.

Alpha-1 antitrypsin deficiency (AATD) can present with hepatic dysfunction in individuals from infancy to adulthood and with chronic obstructive lung disease (emphysema and/or bronchiectasis), characteristically in individuals older than age 30 years. Individuals with AATD are also at increased risk for panniculitis (migratory, inflammatory, tender skin nodules which may ulcerate on legs and lower abdomen) and C-ANCA-positive vasculitis (granulomatosis with polyangiitis). Phenotypic expression varies within and between families. In adults, smoking is the major factor in accelerating the development of COPD; nonsmokers may have a normal life span, but can also develop lung and/or liver disease. Although reported, emphysema in children with AATD is extremely rare. AATD-associated liver disease, which is present in only a small portion of affected children, manifests as neonatal cholestasis. The incidence of liver disease increases with age. Liver disease in adults (manifesting as cirrhosis and fibrosis) may occur in the absence of a history of neonatal or childhood liver disease. The risk for hepatocellular carcinoma (HCC) is increased in individuals with AATD.

Glycogen storage disease type I (GSD I) is characterized by accumulation of glycogen and fat in the liver and kidneys resulting in hepatomegaly and nephromegaly. Severely affected infants present in the neonatal period with severe hypoglycemia due to fasting intolerance. More commonly, untreated infants present at age three to four months with hepatomegaly, severe hypoglycemia with or without seizures, lactic acidosis, hyperuricemia, and hypertriglyceridemia. Affected children typically have doll-like faces with full cheeks, relatively thin extremities, short stature, and a protuberant abdomen. Xanthoma and diarrhea may be present. Impaired platelet function and development of reduced or dysfunctional von Willebrand factor can lead to a bleeding tendency with frequent epistaxis and menorrhagia in females. Individuals with untreated GSD Ib are more likely to develop impaired neutrophil and monocyte function as well as chronic neutropenia resulting in recurrent bacterial infections, gingivitis, periodontitis, and genital and intestinal ulcers. Long-term complications of untreated GSD I include short stature, osteoporosis, delayed puberty, renal disease (including proximal and distal renal tubular acidosis, renal stones, and kidney failure), gout, systemic hypertension, pulmonary hypertension, hepatic adenomas with potential for malignancy, pancreatitis, and polycystic ovaries. Seizures and cognitive impairment may occur in individuals with prolonged periods of hypoglycemia. Normal growth and puberty are expected in treated children. Most affected individuals live into adulthood.

Familial porphyria cutanea tarda (F-PCT) is characterized by: skin findings including blistering over the dorsal aspects of the hands and other sun-exposed areas of skin, skin friability after minor trauma, facial hypertrichosis and hyperpigmentation, and severe thickening of affected skin areas (pseudoscleroderma); and an increased risk for hepatocellular carcinoma (HCC).

Untreated tyrosinemia type I usually presents either in young infants with severe liver involvement or later in the first year with liver dysfunction and renal tubular dysfunction associated with growth failure and rickets. Untreated children may have repeated, often unrecognized, neurologic crises lasting one to seven days that can include change in mental status, abdominal pain, peripheral neuropathy, and/or respiratory failure requiring mechanical ventilation. Death in the untreated child usually occurs before age ten years, typically from liver failure, neurologic crisis, or hepatocellular carcinoma. Combined treatment with nitisinone and a low-tyrosine diet has resulted in a greater than 90% survival rate, normal growth, improved liver function, prevention of cirrhosis, correction of renal tubular acidosis, and improvement in secondary rickets.

Glycogenosis due to glucose-6-phosphatase deficiency (G6P) type b, or glycogen storage disease (GSD) type 1b, is a type of glycogenosis due to G6P deficiency (see this term).

Budd-Chiari syndrome (BDCHS) is defined as thrombosis of one or more of the large hepatic veins, the inferior vena cava, or both. Patients present with a classic clinical triad of abdominal pain, hepatomegaly, and ascites, typically associated with nonspecific elevations of liver enzymes. The disorder may be acute, subacute, or chronic. Edema of the legs may be present (summary by Chung et al., 2006).

MPV17-related mitochondrial DNA (mtDNA) maintenance defect presents in the vast majority of affected individuals as an early-onset encephalohepatopathic (hepatocerebral) disease that is typically associated with mtDNA depletion, particularly in the liver. A later-onset neuromyopathic disease characterized by myopathy and neuropathy, and associated with multiple mtDNA deletions in muscle, has also rarely been described. MPV17-related mtDNA maintenance defect, encephalohepatopathic form is characterized by: Hepatic manifestations (liver dysfunction that typically progresses to liver failure, cholestasis, hepatomegaly, and steatosis); Neurologic involvement (developmental delay, hypotonia, microcephaly, and motor and sensory peripheral neuropathy); Gastrointestinal manifestations (gastrointestinal dysmotility, feeding difficulties, and failure to thrive); and Metabolic derangements (lactic acidosis and hypoglycemia). Less frequent manifestations include renal tubulopathy, nephrocalcinosis, and hypoparathyroidism. Progressive liver disease often leads to death in infancy or early childhood. Hepatocellular carcinoma has been reported.

Citrin deficiency can manifest in newborns or infants as neonatal intrahepatic cholestasis caused by citrin deficiency (NICCD), in older children as failure to thrive and dyslipidemia caused by citrin deficiency (FTTDCD), and in adults as recurrent hyperammonemia with neuropsychiatric symptoms in citrullinemia type II (CTLN2). Often citrin deficiency is characterized by strong preference for protein-rich and/or lipid-rich foods and aversion to carbohydrate-rich foods. NICCD. Children younger than age one year have a history of low birth weight with growth restriction and transient intrahepatic cholestasis, hepatomegaly, diffuse fatty liver, and parenchymal cellular infiltration associated with hepatic fibrosis, variable liver dysfunction, hypoproteinemia, decreased coagulation factors, hemolytic anemia, and/or hypoglycemia. NICCD is generally not severe and symptoms often resolve by age one year with appropriate treatment, although liver transplantation has been required in rare instances. FTTDCD. Beyond age one year, many children with citrin deficiency develop a protein-rich and/or lipid-rich food preference and aversion to carbohydrate-rich foods. Clinical abnormalities may include growth restriction, hypoglycemia, pancreatitis, severe fatigue, anorexia, and impaired quality of life. Laboratory changes are dyslipidemia, increased lactate-to-pyruvate ratio, higher levels of urinary oxidative stress markers, and considerable deviation in tricarboxylic acid (TCA) cycle metabolites. One or more decades later, some individuals with NICCD or FTTDCD develop CTLN2. CTLN2. Presentation is sudden and usually between ages 20 and 50 years. Manifestations are recurrent hyperammonemia with neuropsychiatric symptoms including nocturnal delirium, aggression, irritability, hyperactivity, delusions, disorientation, restlessness, drowsiness, loss of memory, flapping tremor, convulsive seizures, and coma. Symptoms are often provoked by alcohol and sugar intake, medication, and/or surgery. Affected individuals may or may not have a prior history of NICCD or FTTDCD.

Alagille syndrome (ALGS) is a multisystem disorder with a wide spectrum of clinical variability; this variability is seen even among individuals from the same family. The major clinical manifestations of ALGS are bile duct paucity on liver biopsy, cholestasis, congenital cardiac defects (primarily involving the pulmonary arteries), butterfly vertebrae, ophthalmologic abnormalities (most commonly posterior embryotoxon), and characteristic facial features. Renal abnormalities, growth failure, behavioral differences, splenomegaly, retinal changes, and vascular abnormalities may also occur.

Hepatocellular carcinoma is the major histologic type of malignant primary liver neoplasm. It is the fifth most common cancer and the third most common cause of death from cancer worldwide. The major risk factors for HCC are chronic hepatitis B virus (HBV) infection, chronic hepatitis C virus (HCV) infection, prolonged dietary aflatoxin exposure, alcoholic cirrhosis, and cirrhosis due to other causes. Hepatoblastomas comprise 1 to 2% of all malignant neoplasms of childhood, most often occurring in children under 3 years of age. Hepatoblastomas are thought to be derived from undifferentiated hepatocytes (Taniguchi et al., 2002).

Glycogen storage disease type I (GSD I) is characterized by accumulation of glycogen and fat in the liver and kidneys resulting in hepatomegaly and nephromegaly. Severely affected infants present in the neonatal period with severe hypoglycemia due to fasting intolerance. More commonly, untreated infants present at age three to four months with hepatomegaly, severe hypoglycemia with or without seizures, lactic acidosis, hyperuricemia, and hypertriglyceridemia. Affected children typically have doll-like faces with full cheeks, relatively thin extremities, short stature, and a protuberant abdomen. Xanthoma and diarrhea may be present. Impaired platelet function and development of reduced or dysfunctional von Willebrand factor can lead to a bleeding tendency with frequent epistaxis and menorrhagia in females. Individuals with untreated GSD Ib are more likely to develop impaired neutrophil and monocyte function as well as chronic neutropenia resulting in recurrent bacterial infections, gingivitis, periodontitis, and genital and intestinal ulcers. Long-term complications of untreated GSD I include short stature, osteoporosis, delayed puberty, renal disease (including proximal and distal renal tubular acidosis, renal stones, and kidney failure), gout, systemic hypertension, pulmonary hypertension, hepatic adenomas with potential for malignancy, pancreatitis, and polycystic ovaries. Seizures and cognitive impairment may occur in individuals with prolonged periods of hypoglycemia. Normal growth and puberty are expected in treated children. Most affected individuals live into adulthood.

Disease with characteristics of early childhood onset of severe progressive liver disease. Caused by homozygous or compound heterozygous mutation in the TJP2 gene on chromosome 9q21.

HFE-related hemochromatosis (HFE HC) is characterized by increased intestinal iron absorption and increased recycling of iron derived from senescent red blood cells. The phenotypic spectrum of HFE HC includes clinical HFE HC (increased serum ferritin and transferrin saturation and end-organ damage secondary to iron overload), biochemical HFE HC (increased serum ferritin and transferrin saturation without end-organ damage), and non-penetrant HFE HC (neither clinical manifestations of HFE HC nor iron overload are present, although elevated transferrin saturation may occur). Clinical HFE HC is characterized by excessive iron in the liver, pancreas, heart, skin, joints, and anterior pituitary gland. In untreated individuals, early manifestations include weakness, chronic fatigue, abdominal pain, weight loss, arthralgias, and diabetes mellitus. Individuals with HFE HC have an increased risk of cirrhosis when their serum ferritin is higher than 1,000 µg/L. Other findings of severe iron overload include hypogonadism, congestive heart failure, arrhythmias, and progressive increase in skin pigmentation. Clinical HFE HC is more common in males than females.

The phenotypic spectrum of ATP8B1 deficiency ranges from severe through moderate to mild. Severe ATP8B1 deficiency is characterized by infantile-onset cholestasis that progresses to cirrhosis, hepatic failure, and early death. Although mild-to-moderate ATP8B1 deficiency initially was thought to involve intermittent symptomatic cholestasis with a lack of hepatic fibrosis, it is now known that hepatic fibrosis may be present early in the disease course. Furthermore, in some persons with ATP8B1 deficiency the clinical findings can span the phenotypic spectrum, shifting over time from the mild end of the spectrum (episodic cholestasis) to the severe end of the spectrum (persistent cholestasis). Sensorineural hearing loss (SNHL) is common across the phenotypic spectrum.

Ruijs-Aalfs syndrome (RJALS) is a segmental progeroid disorder characterized by early onset hepatocellular carcinoma, genomic instability, and progeroid features (summary by Lessel et al., 2014).

Silver-Russell Syndrome (SRS) is typically characterized by gestational growth restriction resulting in affected individuals being born small for gestational age, with relative macrocephaly at birth (head circumference =1.5 standard deviations [SD] above birth weight and/or length), prominent forehead with frontal bossing, and frequently body asymmetry. This is typically followed by postnatal growth failure, and in some cases progressive limb length discrepancy and feeding difficulties. Additional clinical features include triangular facies, fifth finger clinodactyly, and micrognathia with narrow chin. Except for the limb length asymmetry, growth failure is proportionate and head growth typically normal. The average adult height in untreated individuals is ~3.1±1.4 SD below the mean. The Netchine-Harbison Clinical Scoring System (NH-CSS) is a sensitive diagnostic scoring system. Clinical diagnosis can be established in an individual who meets at least four of the NH-CSS clinical criteria – prominent forehead/frontal bossing and relative macrocephaly at birth plus two additional findings – and in whom other disorders have been ruled out.

Noncirrhotic portal hypertension-2 (NCPH2) is an autosomal recessive disorder characterized by signs of liver dysfunction that become apparent in the first decades of life. Affected individuals have jaundice, hyperbilirubinemia, pancytopenia, including neutropenia, lymphopenia, and thrombocytopenia, hepatosplenomegaly, and esophageal varices. Some patients may have recurrent infections or features suggestive of an immunodeficiency. Liver biopsy is notable for the absence of cirrhosis and the presence of nodular regeneration. Liver sinusoidal endothelial cells (LSECs) have abnormal expression of CD34 (142230) (summary by Drzewiecki et al., 2021). For a discussion of genetic heterogeneity of NCPH, see 617068.

Hepatorenocardiac degenerative fibrosis (HRCDF) is a primarily fibrotic disease affecting the liver, kidney, and heart, with considerable variability in disease onset and expression. Affected individuals develop degenerative hepatic fibrosis in childhood or early adulthood, with variable later onset of fibrocystic kidney disease and hypertrophic cardiomyopathy (Devane et al., 2022).