RESUMEN
From July 1971 until December 1978 we treated 19 male and 5 female children less than 1 year old for ureteropelvic junction obstruction. Diagnosis was based on high dose excretory urography with delayed films. Ultrasound was performed in some cases to confirm hydronephrosis. Cystoscopy and retrograde pyelography were not required. Of 32 obstructed kidneys 27 were repaired by dismembered reduction pyeloureteroplasty. Of 8 patients with bilateral involvement 3 underwent unilateral repair only because of lesser contralateral obstruction and 1 underwent unilateral nephrectomy. Of the 27 repairs 20 were protected by nephrostomy or pyelostomy drainage plus a small caliber silicone rubber or polyvinyl stent. Of the 6 non-stented repairs 2 had delayed opening of the repair. A frozen section renal biopsy aided in a decision to repair the kidney in 4 of 6 instances and in 10 other instances a renal biopsy was obtained for prognostic purposes. There were no secondary nephrectomies, although 2 boys required reoperations for a successful result. Instillation pyelography with fluoroscopic monitoring was used to determine when the tubes could be removed. Generally, we removed the stent 4 or 5 days postoperatively and the nephrostomy at a variable time after demonstration of patency of repair. In this group of small children pyelostomy or nephrostomy and intubation of the repair are useful additions to the surgical technique to prevent obstruction of the tiny and delicate infant ureter by anastomotic edema or kinking of the repair.