Increased levels of protein in the urine.

Accumulation of scar tissue within the glomerulus.

The accumulation of collagen and related extracellular matrix (ECM) molecules in the interstitium of the kidney. The interstitium is expanded by the presence of collagen that stain blue on trichrome. Tubules are not back to back, but rather separated by fibrosis and can be atrophic.

Hypoplasia of the kidney.

The nephronophthisis (NPH) phenotype is characterized by reduced renal concentrating ability, chronic tubulointerstitial nephritis, cystic renal disease, and progression to end-stage renal disease (ESRD) before age 30 years. Three age-based clinical subtypes are recognized: infantile, juvenile, and adolescent/adult. Infantile NPH can present in utero with oligohydramnios sequence (limb contractures, pulmonary hypoplasia, and facial dysmorphisms) or postnatally with renal manifestations that progress to ESRD before age 3 years. Juvenile NPH, the most prevalent subtype, typically presents with polydipsia and polyuria, growth retardation, chronic iron-resistant anemia, or other findings related to chronic kidney disease (CKD). Hypertension is typically absent due to salt wasting. ESRD develops at a median age of 13 years. Ultrasound findings are increased echogenicity, reduced corticomedullary differentiation, and renal cysts (in 50% of affected individuals). Histologic findings include tubulointerstitial fibrosis, thickened and disrupted tubular basement membrane, sporadic corticomedullary cysts, and normal or reduced kidney size. Adolescent/adult NPH is clinically similar to juvenile NPH, but ESRD develops at a median age of 19 years. Within a subtype, inter- and intrafamilial variability in rate of progression to ESRD is considerable. Approximately 80%-90% of individuals with the NPH phenotype have no extrarenal features (i.e., they have isolated NPH); ~10%-20% have extrarenal manifestations that constitute a recognizable syndrome (e.g., Joubert syndrome, Bardet-Biedl syndrome, Jeune syndrome and related skeletal disorders, Meckel-Gruber syndrome, Senior-Løken syndrome, Leber congenital amaurosis, COACH syndrome, and oculomotor apraxia, Cogan type).

Obliteration of the glomerular capillary lumen by increased collagenous matrix, with or without hyalinosis or foam cells. Sclerosis involves 100% of the glomerular tuft. Relative to other patent glomeruli in the sample, glomerular size is preserved, or increased/decreased by no more than 50%.

A degree of kidney failure severe enough to require dialysis or kidney transplantation for survival characterized by a severe reduction in glomerular filtration rate (less than 15 ml/min/1.73 m2) and other manifestations including increased serum creatinine.

Mildly increased levels of protein in the urine (150-500 mg per day in adults).

A type of glomerular subepithelial deposit characterized by finely granular material deposited between the outer (epithelial) aspect of the glomerular basement membrane (GBM) and the visceral epithelial cell, with varying degrees of incorporation into the GBM and corresponding to immunoglobulin and/or complement by immunofluorescence/immunohistochemistry. This feature is associated with a prominent GBM reflecting an diffuse and relatively uniform increase in thickness (subjective estimate).

Duplicated basement membranes of the peritubular capillaries located in the medulla of the kidney and arranged in multiple concentric layers.

A deficiency or slowing down of growth pre- and postnatally.

A cyst of the pancreas that possess a lining of mucous epithelium.

A cystic lesion located in the liver.

Increased diameter (caliber) of intrahepatic bile ducts (bile ducts that transport bile between the Canals of Hering and the interlobar bile ducts).