Posterior urethral valves

Posterior urethral valves (PUV) represent an important clinical problem due to their high morbidity. In particular, the frequent association with renal dysplasia, and chronic obstruction with subsequent hydroureteronephrosis are the major causes of progressive renal failure. Early diagnosis and infection control, suitable elective surgery, urodynamic study of functional alterations, improvement of management of nephrologic alterations, dialysis and early transplantation have greatly contributed to survival increase over the last few years. The diagnosis is made in the first year of life in about 70% of cases and at birth in about 50%. Hydroureteronephrosis is present in severe cases and is frequently associated with respiratory distress. When PUV is suspected at US examination, endoscopy should follow to obtain a correct evaluation and to start initial treatment. Cystography is equally necessary to evaluate accurately the urethral profile and to study side effects, since reflux is present in 50% of cases. Treatment should be very early in the newborn to reduce the risk of renal injury due to stasis and back pressure. The final aim is to obtain prognostic improvement by optimizing and preserving glomerular, tubular and vesico-urethral functions. In the initial phases, a urinary diversion could be sufficient before definitive valve resection. Concerning prenatally diagnosed cases, intrauterine therapeutic procedures have been widely discussed and also criticised. Unfortunately, notwithstanding the high diagnostic and therapeutic aggressiveness, PUV still present an unfavourable evolution as regards renal function, with an incidence of chronic renal failure of 28-45% and of end renal failure of 13-28%. The authors present a review of the literature and their personal clinical experience.