Oligomeganephronia

**Definition:** Oligomeganephronic renal hypoplasia is a severe developmental defect of both kidneys characterised by a reduced number of nephrons (the functional unit of the kidney), hypertrophic glomeruli with diameters twice the normal size, hypertrophic tubules and thickening of Bowman's capsule, occurring in the absence of a urinary tract malformation.

**Long definition:** Oligomeganephronic renal hypoplasia is a severe developmental defect of both kidneys characterized by a reduced number of nephrons, hypertrophic glomeruli with diameters twice the normal size, hypertrophic tubules and thickening of Bowman's capsule, occurring in the absence of a urinary tract malformation. Patients may present at birth with renal failure, defects in urine concentration, urinary sodium loss or acidosis. During the first year of life, the usual symptom is persistent anorexia with vomiting, and height-weight growth delay. This condition is often associated with progressive loss of kidney function and eventually kidney failure.