label: renal hypoplasia
label_lc: renal hypoplasia
description: Renal hypoplasia is a developmental anomaly in which one or both kidneys (unilateral or bilateral renal hypoplasia, respectively) have a deficit in the number of nephrons and may be small. Oligomeganephronia represents a severe variant of hypoplasia in which nephron number is reduced by 80% and nephrons are markedly hypertrophied.