Urine Extravasation Secondary to Upper Urinary Tract Obstruction By Selwyn B. Levitt and tetty G. Lutzker
OWER UR I N A R Y T R A C T OBSTRUCT.ION is a well-documented cause o f " s p o n t a n e o u s " urine extravasation in neonates. This report describes a case of apparent urine extravasation secondary to ureteropelvic junction obstruction, where primary reconstructive surgery salvaged a functioning kidney.
CASE REPORT A 2-day-old male, the product of a normal gestation and apparently atraumatic delivery, was admitted with abdominal distention. Physical examination revealed a large, tense, left-sided abdominal mass. High dose intravenous urography (5 cc/kg) was performed and the study was followed through for 18 hr. Contrast slowly opacified the hugely dilated calyces and pelvis without visualizing the ureter. The right kidney appeared normal (Fig. 1). No extravasation of contrast was seen on the urogram. The voiding cystourethrogram, urinalysis and the serum BUN and creatinine were within normal limits. Retroperitoneal flank exploration through a subcostal incision at 4 days of age revealed a massively dilated renal pelvis, with organizing hematoma within its wall. Intrapelvic pressure measured 30 cm of water. There was a fibrous pseudocapsule around the kidney and renal pelvis, with adhesions to the overlying peritoneum and the descending colon. No gross perforation was seen. An Anderson-Hynes dismembered pyeloplasty was performed with excision of the redundant renal pelvis. A nephrostomy tube was left indwelling for temporary urinary diversion. The endogenous creatinine clearance of the left kidney measured through the nephrostomy tube was 20 cc/min/1.73 m 2. Pathologic examination of the excised portions of ureter and pelvis demonstrated areas of hemorrhage on the serosal surface, as well as capillary formation indicating organizing hematoma, suggesting that the "rupture" was > 2 days old. There were also areas of focal fibrosis. Follow-up intravenous urography performed at 18 me of age demonstrated prompt left renal opacification, considerably less dilatation of the collecting system than preoperatively, and a 5 mm cortical margin (Fig. 2). The right kidney remained normal.
DISCUSSION A l t h o u g h R a v i c h a n d S c h e l l 6 d e s c r i b e d f r a n k r e n a l r u p t u r e in a n e o n a t e w i t h u r e t e r o p e l v i c j u n c t i o n o b s t r u c t i o n s e c o n d a r y to c o n g e n i t a l s t r i c t u r e , s p o n t a n e o u s l e a k a g e f r o m t h e u r i n a r y t r a c t in i n f a n t s h a s b e e n seen m u c h m o r e fre9 q u e n t l y as a c o m p l i c a t i o n o f l o w e r u r i n a r y t r a c t o b s t r u c t i o n . 3,5 M a n y o f t h e s e cases h a v e b e e n a s s o c i a t e d w i t h u r i n e ascites in t h e n e o n a t a l p e r i o d . T h e m e c h a n i s m a p p e a r s t o be d i s r u p t i o n o f a c a l y c e a l f o r n i x , c a u s i n g e x t r a v a s a t i o n o f urine with varying amounts of blood into the subcapsular space and into G e r o t a ' s fascia. I f sufficient e x t r a v a s a t i o n o c c u r s , r u p t u r e i n t o t h e p e r i t o n e a l c a v i t y will f o l l o w , s From the Division of Pediatric Urology, Albert Einstein College of Medicine and Montefiore Hospital and Medical Center and the Department of Radiology, Albert Einstein College of Medicine, Bronx, N. Y. Address for reprint requests: Selwyn B. Levitt, M.D., Department of Pediatric Urology, Albert Einstein College of Medicine, Bronx, N. Y. 10461. 9 1976 by Grune & Stratton, Inc. Journal of Pediatric Surgery, Vol. 11, No. 4 (August), 1976
LEVITT AND LUTZKER
Eighteen-hour film of IVP demonstrating enormous left renal pelvis opacif;ed.
Interestingly, it is usually the upper urinary tract which leaks, whether the site of obstruction is distal or proximal. Microradiographic studies of hydronephrotic cadaver kidneys have demonstrated periforniceal collections of Micropaque even where gross evidence of rupture was not evident radiographically. 3
Fig. 2. Film from IVP performed 18 mo after surgery, demonstrating growth of renal cortex, as well as reduced size and improved opacification of left pelvocalyceal system.
To the best of our knowledge, this is the first reported case of renal salvage in a neonate with presumed spontaneous perirenal leakage of urine associated with ureteropelvic junction obstruction. Many instances of such extravasation in this age group have been described with lower urinary tract obstructions. As in the latter cases, the occurrence of extravasation secondary to upper tract obstruction need not preclude primary reconstruction. REFERENCES
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4. Jeppesen FB: Spontaneous rupture of the kidney. Urol 86:489 492, 1961 5. Moncada R, Wang W J, Love L, et al: Neonatal ascites associated with urinary outlet obstruction (urine ascites). Radiology 90:11651170, 1968 6. Ravich L, Schell NB: Rupture of the kidney in a newborn infant. NY State J Med 2822-2824, 1961 7. Weller MH, Miller K: Unusual aspects of urine ascites. Radiology 109:665-669, 1973