Posterior urethral valves: pathophysiology and clinical implications.

Posterior urethral valves are a congenital defect affecting the prostatic urethra. They may be the most common cause of obstructive uropathy leading to childhood renal failure. Patients exhibit a broad spectrum of symptomatology and pathology that are determined by the degree and duration of obstruction, the presence or absence of urinary infection, and the extent of renal dysplasia. With early detection and proper treatment, which may include renal transplantation, the outlook for these children has improved significantly.