A study of the sequelae of posterior urethral valves.

We discuss the drainage procedures prior to valve ablation and the long-term sequelae in the upper urinary tract of 135 boys with posterior urethral valves. Cutaneous ureterostomy in infants, which had been used previously, now has been replaced largely by lower tract drainage using stab cystotomy combined with irrigation. The former technique is reserved for those few patients who do not improve. Older patients require no preliminary drainage. The long-term sequelae were studied with respect to urinary control, the fate of ureteral reflux and the state of upper tract dilatation. Of our patients 14 per cent remain incontinent owing to too radical a transurethral resection, bladder neck surgery or a gross degree of urethral dilatation found in neonates. Only 32 per cent of the renal units were presented with ureteral reflux. After valve ablation moderate or gross reflux ceased spontaneously in 29 per cent of the patients, it persisted in 35 per cent and it required antireflux surgery or nephrectomy in 36 per cent. The upper urinary tracts were dilated in 90 per cent of the renal units and most had moderate or gross dilatation, especially in infants. Of 116 united with moderate or gross dilatation, or nonfunction 65 per cent remained unchanged after valve ablation but 35 per cent improved to normal or nearly normal. In 35 units with persistent dilatation in nonrefluxing systems the dilatation was associated with pelvioureteral or vesicoureteral obstruction in 10 units, although in 25 patients no obstruction could be identified. The dilatation was considered to be a manifestation of developmental dysplasia of the ureters.