Posterior urethral valves Posterior urethral valves occur in around 1 in 5000-8000 live male bihs. The valves are membranes that have a small posterior slit within them, which typically lie just distal to the verumontanum and cause obstruction to the urethra of boys. They function as flap valves and so although they are obstructive to antegrade urinary flow, a urethral catheter can be passed retrogradely without any difficulty. Clinical features Newborns may present with palpable abdominal masses (distended bladder, hydronephrotic kidney & Ascites) Infants with Urinary infection & sepsis. Sometimes, the valves are incomplete and the patient remains without symptoms untill adolescence or adulthood Approximately 30% of patients experience end stage renal disease Vesicoureteral reflux occurs in 50% of patients DIAGNOSIS Posterior urethral valves need to be detected and treated as early as possible to minimise the degree of renal failure. The presentation varies according to the severity of the obstruction. The more severe the obstruction, the earlier the presen tation. Diagnosis is most commonly made antenatally with ultrasound, which demonstrates bilateral hydronephrosis above a distended bladder. If the diagnosis is not made antenatally, then babies typically present with urinary infection in the neonatal period or with uraemia and renal failure. Rarely the valves are incomplete and the patient is symp tom free until adolescence or adulthood, when again urinary infection or renal impairment can supervene. Investigation will involve a voiding cystogram, with the dilatation of the urethra above the valves demonstrable on a voiding cystogram. The bladder is hypero phied and often shows diveicula. Typically, there is vesico- ureteric reflux into dilated upper tracts. The valves themselves can be difficult to see on urethroscopy because the flow ofirrigant sweeps them into the open position. Renal function is usually impaired, albeit to a varying degree, and the extent is fuher assessed by measurement of ultrasound scanning, which will assess the renal coical thickness, and renography to assess differential renal function. TREATMENT Initial treatment is by catheterisation to relieve the obstruction and to allow the effects of renal failure to improve. Definitive treatment is by endoscopic destruction of the valves with continuing lifelong suppoive treatment of the dilated urinary tract, the recurrent urinary infections and the uraemia. Ref: Bailey and love 27th edition Pgno : 1478