title: Protective factors in posterior urethral valves.
abstract: Patients with posterior urethral valves may present with or contract renal insufficiency. High intravesical pressure that is transmitted to the upper urinary tract in utero is a likely contributing cause. We have identified 3 anatomical associations with posterior urethral valves that provide a pressure "pop-off" mechanism resulting in preservation of better renal function: 1) the syndrome of posterior urethral valves, unilateral vesicoureteral reflux and renal dysplasia; 2) large congenital type bladder diverticula and 3) urinary extravasation with or without urinary ascites. Followup of 71 boys with posterior urethral valves was sufficient to permit long-term analysis. Serum creatinine was used as an index of renal function and prognosis. Of the 71 boys 20 (28 per cent) had 1 of the 3 protective mechanisms. Only 1 child (5 per cent) had a serum creatinine greater than 1.0 mg. per cent. Of the remaining 51 boys without a "pop-off" mechanism 20 (39 per cent) had serum creatinine greater than 1.0 mg. per cent and 7 had already progressed to renal dialysis and/or transplantation. The difference in serum creatinine was statistically significant (p less than 0.01). Thus, the syndrome of posterior urethral valves, unilateral vesicoureteral reflux and renal dysplasia; large congenital bladder diverticula and urinary extravasation can serve as a "pop-off" mechanism to buffer high pressures in the urinary tract and to lead to the preservation of better renal function in boys with posterior urethral valves.
mesh_terms: D002675:Child, Preschool; D003404:Creatinine / Q000097:blood; D004240:Diverticulum / Q000151:congenital*; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007668:Kidney / Q000002:abnormalities* / Q000503:physiopathology; D007676:Kidney Failure, Chronic / Q000209:etiology*; D008297:Male; D011379:Prognosis; D013577:Syndrome; D013997:Time Factors; D014521:Urethra / Q000002:abnormalities*; D001745:Urinary Bladder Diseases / Q000151:congenital*; D014556:Urine; D014718:Vesico-Ureteral Reflux / Q000150:complications*
chemical_list: D003404:Creatinine