Obstructive or reflux nephropathy

**Definition:** Distention of the pelvis and calices of the kidney with urine as a result of obstruction of the ureter or as a result of a vesicoureteral or vesicoureterorenal reflux of urine. Diffuse or focal cortical scarring and chronic tubulointerstitial nephritis may be present.

**Exclusions:** - Calculus of kidney and ureter without hydronephrosis - Obstructive pyelonephritis