Neonatal ascites associated with urinary outlet obstruction (urine ascites)

Management of urinary extravasation in 18 boys with posterior urethral valves

PURPOSE

Urinary extravasation with associated posterior urethral valves is uncommon and published articles are restricted to case reports. We propose a management algorithm on the basis of presentation of 18 boys with this condition.

MATERIALS AND METHODS

In this retrospective review we analyze the clinical features, diagnostic radiological imaging (voiding cystourethrogram and (99m)technetium mercaptoacetyltriglycine scan) and measured glomerular filtration rate (GFR) for assessment of renal function in boys presenting with posterior urethral valves and urinary extravasation. Indications for surgical intervention and long-term outcome were evaluated. Results are presented as mean +/- SD.

RESULTS

Patient age at presentation was 4 days (range 1 to 28). Salient features at presentation were abdominal distention in 55.5% of cases, flank mass in 55.5%, respiratory distress in 16.6% and septicemia in 22.2%. Patients were categorized into group 1 with ascites (6 boys) and group 2 without ascites (12). Followup was 70.8 +/- 5.6 months. In group 1 the 3 boys with ascites alone had a followup GFR of 29 versus 74 ml. per minute per 1.73 m.2 in 3 with urinoma plus ascites (p = 0.001) at 64 +/- 4.9 months. In group 2 the GFR in 3 boys with bilateral urinoma was 104.7 +/- 30.4 versus 54.3 +/- 29.4 ml. per minute per 1.73 m.2 in the other 9 with unilateral urinoma (p = 0.001) at 36 +/- 4.2 and 81.3 +/- 4.7 months, respectively. The ipsilateral kidney showed reduced function in 6 of 12 boys with unilateral urinoma from both groups.

CONCLUSIONS

Renal function on the side of the urinoma is impaired, and the majority of patients have impaired global renal function. A management algorithm is proposed.

Neonatal urinary ascites due to unilateral vesicoureteric junction obstruction

A case of unilateral vesicoureteric junction obstruction presenting with ascites in a neonate managed successfully with serial ultrasonography and delayed primary reconstruction is described.

Obstructed solitary pelvic kidney and urinary ascites

We report on a patient with a congenital pelvic kidney who presented with anuria and urinary ascites. Extensive pelvic endometriosis involving the ureteropelvic junction was the cause of severe obstruction. We discuss successful management of this condition and review the literature.

The hyponatremia of neonatal urinary ascites: clinical observations, experimental confirmation and proposed mechanism

A case of neonatal urinary ascites with severe hyponatremia is reported. Critical review of the literature on neonatal urinary ascites, which included determination of serum electrolytes, revealed a 70% incidence of hyponatremia. In an attempt to explain the mechanism of the hyponatremia, urinary ascites was produced in rats by creation of either a unilateral (uretero-peritoneal) or bilateral (vesicoperitoneal) shunt. Hyponatremia did not occur in the unilateral group but it was profound in the bilateral group. At 48 hours postoperatively renin was unchanged in the unilateral group but it was significantly elevated in the bilateral group. Aldosterone was elevated in the unilateral group and markedly elevated in the bilateral group. Urine entering the peritoneal cavity equilibrates with plasma. The proposed mechanism of hyponatremia in the bilateral group is autodialysis with intraperitoneal urine containing progressively lower sodium concentration secondary to increased renin and aldosterone.

Congenital bladder rupture and urine ascites secondary to a sacrococcygeal teratoma

A case of congenital bladder rupture with urine ascites and bilateral hydronephrosis secondary to a sacrococcygeal teratoma obstructing the bladder outlet is presented. As no evidence of pulmonary hypoplasia and renal dysplasia was present, with rapid recovery of renal function after decompressive surgery, the infravesical obstruction probably occurred late in the fetal period. The bladder rupture resulting in internal decompression may have constituted an additional protective mechanism for the preservation of renal function.

Urinoma formation in posterior urethral valves: relationship to later renal function

A retrospective analysis of radiologically determined individual renal function was performed in five boys who presented in the neonatal period with posterior urethral valves, vesicoureteral reflux and documented urinoma formation. Renal function was evaluated with scintigraphy. There was reflux in eight of ten ureters. Six of these ureters had an associated urinoma and compromised renal function in the neonatal period. In two of the boys the kidney with urinoma functioned better than the contralateral kidney with reflux alone. In two other boys with unilateral urinoma the contralateral ureter did not reflux and the affected kidney functioned less well. In follow up (20 to 36 months) seven of the ten kidneys have a near normal appearance or function. Those kidneys which are now abnormal were noted to be abnormal in the neonatal period.

Contained neonatal urinoma: management and functional results

Between 1970 and 1985, 10 male newborns with a contained urinoma were treated at our institution. An underlying congenital obstructive uropathic condition was discovered in every patient, the most common of which was posterior urethral valves. All 10 patients underwent surgical correction of the primary obstructive process. Direct drainage of the urinoma was required in 4 patients because of progressive clinical symptoms. Radiographic and renal functional parameters returned to normal at followup. Clinical presentation, evaluation, treatment and pathophysiology of this rare entity are discussed.

Urinary extravasation in the fetus with obstructive uropathy

Urinary extravasation resulting in either urinary ascites or an isolated perirenal urinoma is relatively common in the fetus with severe obstructive uropathy. We examined the effect of fetal urinary extravasation on the developing kidney and abdominal wall in 12 fetuses taken from a series of 44 cases of fetal urinary tract obstruction. Based on this experience, we conclude that fetal urinary extravasation has predictable pathophysiologic consequences. Fetal urinary ascites appears to ameliorate obstruction-induced renal dysplasia by decompressing the high-pressure, obstructed fetal urinary system. Conversely, contained urinomas secondary to ureteropelvic junction obstruction provide inadequate decompression and are associated with renal dysplasia. Last, the severity of abdominal wall laxity (prune belly) relates directly to the timing and degree of fetal ascites.

Urinothorax as a manifestation of nondilated obstructive uropathy following renal transplantation

A 12-year-old patient developed prolonged nondilated urinary obstruction and pleural effusion shortly after undergoing renal transplantation. Renal sonography, angiography, and isotope renography failed to identify an obstructive process. On the 18th postoperative day, pleural effusion was noted in the right hemithorax, and by day 24, increased perinephric fluid was observed on renal scan. Following a nephrostomy, the pleural effusion resolved and renal function improved remarkably. A ureterovesical junction obstruction and renal pelvis tear that were later discovered were repaired. Whenever a ureteral obstruction is suspected the diagnosis should be pursued vigorously, despite normal radiologic findings, especially in the presence of pleural effusion. Consideration of the possibility of urinothorax in such cases may obviate the need for lung biopsy.

Neonatal bladder rupture: case report and review of literature

Neonatal bladder rupture is rare. A review of the literature revealed less than 16 cases. A case of posterior urethral valves and associated neonatal ascites due to bladder perforation is presented.

Diseases causing fetal and neonatal ascites

Causes of fetal ascites are reviewed, and 3 new cases are reported. A protocol is suggested for intrauterine investigation of the spectrum of diseases causing fetal ascites. There is some overlap with causes of hydrops fetalis.

Pseudotumour of the kidney secondary to posterior urethral valves: the role of renal backflow and perirenal extravasation

In three male neonates, successfully treated for posterior urethral valves, unilateral "pseudotumour" deformity of the collecting system ensued. Two of them had, preoperatively, a marked ipsilateral perirenal urinary extravasation (urinoma), one in addition gross contralateral renal backflow with moderate leakage to the renal capsule. The other one had slight contralateral backflow to the kidney parenchyma but also urinary ascites. The third patient had considerable unilateral renal backflow on the side of developing deformity but no perirenal extravasation. Out of the three patients, two had bilateral Grade IV-V vesico-ureteral reflux, in the third patient reflux of the same degree was present and this only on the side opposite to the deformity. In all three patients the kidney with the "pseudotumour" became taller and more slender than the normally developing mate. There was either slight or no loss of renal parenchyma. At the last follow-up, 1-3 years after diagnosis of the valves, kidney function was normal.

Urinary extravasation in the newborn male with posterior urethral valves

Neonatal urinary extravasation is a rare condition frequently associated with posterior urethral valves in males. At the Babies Hospital, Columbia Presbyterian Medical Center during a 16-yr period, 5 neonates with urinary extravasation and valves presented--of all valve patients. Presentation was characterized by abdominal distention and varying degrees of azotemia. Treatment consisted of upper tract drainage in two cases and lower tract decompression in three. The mortality of this series was zero. At follow-up all five patients had completely normal serum renal function studies; four out of five had essentially normal radiographic studies. Extravasation appeared to protect the upper tracts from significant damage. Successful management of this condition should be tailored to the individual patient.

Neonatal perirenal urinary extravasation with posterior urethral valves

Renal dysplasia and atrophy are associated with congenital urinary tract obstruction, such as posterior urethral valves, and are thought to result from the increased pressure in the developing obstructed urinary system. This increased pressure is likely to be alleviated by perirenal urinary extravasation and urinary ascites. Whether this relief of pressure in the obstructed developing kidney results in a lessened degree of renal abnormality is likely to depend on the time during the period of gestation when the urinary leak occurs and the degree of renal dysplasia and atrophy at the time of the urinary leak.

Neonatal urinary ascites secondary to distal ureteral stenosis

We report a case of neonatal urinary ascites secondary to distal ureteral stenosis. We believe that this is the first reported case of urinary ascites secondary to distal ureteral stenosis with a normal contralateral kidney and ureter.

Urinary ascites in the newborn

Seven cases of neonatal urinary ascites secondary to obstructive uropathy are reported. In 2 the bladder had perforated; in 4 there was perirenal extravasation; in 1 the site of leakage was not determined. A localised parenchymal perforation was found in 3 kidneys. Treatment was by temporary urinary diversion followed by operative relief of the obstruction. Six patients survive in good health; 1 infant died from causes unrelated to the ascites or the urinary tract. It is suggested that spontaneous urinary tract perforation with the development of ascites is often beneficial in the long term since it decompresses the obstructed system and lessens renal parenchymal damage.

Perirenal urinary extravasation associated with urethral valves in infants

We present 7 cases of urethral valves and perirenal urinary extravasation, and review 37 cases reported previously in the literature. The extravasation usually is from the kidney (66 per cent) and often is associated with reflux (70 per cent). It appears to be a pressure-related phenomenon. Although the mortality associated with the condition is significant (32 per cent) renal function is usually preserved. Prompt treatment with correction of metabolic acidosis, and decompression of the tense abdomen and the urinary tract is recommended.

Management of neonatal urinary ascites

Four cases of neonatal urinary ascites are added to the previous reported 46 cases. Three are males with posterior urethral valves, and one is a female whose bladder was ruptured during traumatic breech extraction. The renal site of urine extravasation was verified by retrograde pyelogram in one instance and operative exploration in another. If relief of the lower urinary tract obstruction does not resolve the ascites, percutaneous or open nephrostomy tube placement on the side of extravasation is advised. With this approach all the patients have survived and now have normal renal function.

Posterior urethral valves managed by cutaneous ureterostomy with subsequent ureteral reconstruction

Six boys, 2 weeks to 5 years old, underwent cutaneous ureterostomy for massively dilated upper urinary tracts secondary to obstruction by posterior urethral valves. Cutaneous ureterostomies had been performed elsewhere in 2 patients. Two patients underwent transurethral fulguration of the valves initially with no improvement. Blood urea nitrogen, creatinine and serum electrolyte values continued to increase and, therefore, cutaneous ureterostomies were performed with dramatic improvement. Two patients presented with sepsis, one of whom had a positive blood culture. Both children had severe pyonephrosis and after the conditions improved with medical treatment cutaneous ureterostomies were done. The total number of surgical procedures required for all patients was 59, including renal biopsies, nephrostomies and cystoscopies. No kidneys, except for the severely dysplastic ones, were lost and all patients resumed normal growth rates and have had no urinary tract infections. All laboratory values are within normal limits.

Clue to diagnosis of neonatal urinary ascites. Relative radioluency of liver shadow

About 25 per cent of neonatal ascites is caused by urinary tract disease. Opacification of the ascitic fluid by leakage of contrast material during cystography or intravenous urography may lead to striking relative radioluency of the liver. This phenomenon may be an important clue to the differential diagnosis of the etiology of neonatal ascites.

Urine extravasation secondary to upper urinary tract obstruction

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.

Oliguria in the incubating neonate. Emergency aortography and urography in neonates using mobile X-ray equipment

Neonates in incubators underwent umbilical aortography, excretory urography and suprapubic cysto-urethrography using a mobile X-ray machine in the Premature Baby Unit to define the cause of their oliguria. The techniques were easy to perform without endangering the infants by moving them. The radiological findings in the four neonates investigated contributed significantly to the management of their illnesses.

Spontaneous rupture of the renal collecting system

Three cases of spontaneous rupture of the collecting system of the kidney are reported on. Organ-saving surgery was feasible in two of them. The etiology and treatment of spontaneous ruptures of the renal pelvis are discussed.

A new dimension in the diagnosis of posterior urethral valves in children

Infants with posterior urethral valves may seem to have diverse and unrelated symptoms when, in fact, the clinical findings are all related to the primary effect of the valves during various stages of early growth. In some, prenatal urinary obstruction leads to such severe oligohydramnios that the fetus is stillborn. Others, somewhat less affected, are born alive but have severe respiratory distress from hypoplastic (stiff) lungs and die of respiratory problems. Still others can be associated with massive ascites and urinomas, and be stillborn or die soon after birth. In less severe cases the neonates may have unexplained respiratory distress with pneumomediastinum or pneumothorax as the only indication of obstructive urologic disease with deficient urinary output. Urinomas or ascites may later develop beyond the neonatal period as the post-natal obstructive effects of the valves accumulate and the urinary system ruptures and decompresses itself. Finally when the urinary system does not decompress itself, the back pressure can lead to rapid and progressive renal damage until the kidneys can no longer concentrate urine and lose water. The infant becomes dry, acidotic and paradoxically at this stage, puts out large quantities of dilute urine. Physicians caring for infants should be highly suspicious of posterior urethral valves in any male infant with unexplained respiratory distress or metabolic derangements, abdominal distension or flank masses.

Urinary ascites and obstructive uropathy

Seven infants with urinary ascites caused by obstructive uropathy are reported. The extravasation occurs in the kidneys and produces an opaque halo, best seen in delayed films at excretory urography. The common cause is a posterior urethral valve which forms an obstructive sail-like structure.