Urinoma and urinary ascites secondary to calyceal perforation in neonatal posterior urethral valves

Neonate with urinary ascites but no hydronephrosis: unusual presentation of posterior urethral valves

Posterior urethral valves (PUV) are an important cause of paediatric obstructive uropathy. PUV are usually diagnosed by prenatal ultrasonography (US) revealing hydronephrosis and bladder distention. We describe a 17-day-old male infant with abdominal distention who had no hydronephrosis on prenatal US. Laboratory investigations showed serum creatinine of 12 mg/dL, hyperkalaemia and metabolic acidosis. Abdominal US showed large amount of ascites, normal-sized kidneys without hydronephrosis and incompletely distended bladder. Paracentesis revealed clear, yellow ascitic fluid with creatinine level of 27 mg/dL compatible with urinary ascites. Voiding cystourethrogram (VCUG) demonstrated PUV with a dilated posterior urethra, grade 5 right vesicoureteral reflux and a ruptured kidney fornix with peritoneal extravasation of contrast. Foley decompression resulted in normalisation of creatinine within 72 hours. Transurethral resection of PUV was performed, and a repeat VCUG showed recovery of forniceal rupture. This case illustrates an unusual presentation of a potentially life-threatening but treatable cause of urinary tract obstruction.

Unusual complication of a urinary stone in a child: spontaneous rupture of the renal pelvis with the migration of calculus into the retroperitoneum

Spontaneous perforation of the renal pelvis and extravasation of urine into the perinephric space is an extremely rare condition in childhood. It is mostly related to underlying congenital urinary tract abnormalities and caused by urolithiasis or infection in the setting of urinary obstruction. Here, we report a case of an 18-month-old female patient with rupture of the renal pelvis by an extruded kidney stone and its management.

Fetal obstructive uropathy complicated by urinary ascites: outcome and prognostic value of fetal serum β-2-microglobulin

OBJECTIVES

To determine whether the prognostic value of fetal serum β-2-microglobulin is altered and whether the occurrence of fetal urinary ascites prevents kidney damage in cases of fetal obstructive uropathy with urinary ascites.

METHODS

This was a retrospective study of cases of fetal bilateral obstructive uropathy that occurred between 2006 and 2010, for which both fetal serum and ascites samples were sent to our laboratory for analysis. β-2-microglobulin was assayed in both fetal serum and the corresponding ascites. Renal outcome was analyzed. Histological features of the kidney in cases of termination of pregnancy and renal function of liveborn infants were recorded.

RESULTS

Fourteen cases with analysis of fetal serum and fetal ascites in a context of urinary obstruction were included. Renal outcome was unfavorable in eight cases (57%) and favorable in six (43%). When fetal serum β-2-microglobulin was < 5 mg/L, renal outcome was favorable in all cases (4/4). When fetal serum β-2-microglobulin was ≥ 5 mg/L, 8/10 cases (80%) had an unfavorable renal outcome (sensitivity, 100%; specificity, 66%).

CONCLUSION

Fetal serum β-2-microglobulin reliably predicts postnatal renal outcome in obstructive uropathy complicated by urinary ascites. Moreover, urine extravasation does not seem to protect fetal renal function.

[Spontaneous intraperitoneal rupture of hydronephrosis in an infant]

Spontaneous intraperitoneal rupture of hydronephrosis is a rare complication. We report a case in a 30-month old boy admitted for fever, with a temperature up to 38.5°C, and abdominal distension. The diagnosis was made intraoperatively. The treatment consisted of an emergency internal urinary diversion and a deferred definitive cure of the pyelo-ureteral junction stenosis. Surgical management in two steps is more prudent and beneficial.

The impact of perinatal urinoma formation on renal function: our experience and review of the literature

INTRODUCTION

A urinoma is a fluid mass consisting of extravasated urine in the perirenal space. Its impact on renal function was analysed.

METHODS

All cases of prenatal and neonatal urinoma reported in the literature were analysed as well as two cases recently observed in our department.

RESULTS

A review of all prenatally diagnosed urinomas revealed 25 cases, for a total of 30 renal units. The cause of obstruction was: lower urinary tract (LUT) obstruction in 16 cases (62.5%), upper urinary tract (UUT) obstruction in seven cases (29.5%) and unknown in two cases (8%). A preserved renal function was found in only 30% of all cases. Furthermore, prognosis for renal function was better in posterior urethral valve (PUV) patients than in uretero-pelvic junction obstruction (UPJO) patients. In addition, we analysed 35 published cases of urinoma with a neonatal onset, without prenatal diagnosis, and secondary to LUT obstruction in 27 cases (77%), UUT obstruction in seven cases (20%), while the underlying cause was unknown in one cases (3%). A preserved renal function was observed in 84% of cases with UUT obstruction and in 80% of cases presenting a LUT obstruction.

CONCLUSIONS

Prognosis concerning renal function seems to be mainly related to two factors: age at presentation and underlying diagnosis. Decompression of the urinary tract by urine extravasation produces the best results in terms of preservation of the renal function in LUT obstruction (75% in prenatal and 84% in postnatal cases); UUT obstruction however is associated with a good prognosis in the neonatal period (80% of preserved renal function) but with a severe impairment (only 20% of preserved renal function) in prenatally detected cases.

Neonato com ascite urinária e ruptura de cálice renal secundárias a válvula de uretra posterior: diagnóstico ultrassonográfico

A literatura relata somente alguns casos de recém-nascidos com ascite urinária, geralmente secundária a ruptura de bexiga urinária e não de um cálice renal. Este relato de caso descreve um caso raro de ascite urinária em recém-nascido com válvula de uretra posterior que teve ruptura de um cálice renal, neste caso diagnosticada, até onde sabemos, pela primeira vez por ultrassonografia.

Urinomas protect renal function in posterior urethral valves--a population based study

BACKGROUND/PURPOSE

Urinomas have been thought to protect renal function in boys with posterior urethral valves (PUVs), although recent reports have disputed this. This study tested the hypothesis that urinomas protect global renal function in boys with PUV.

METHODS

A retrospective analysis of all boys with PUV presenting to a tertiary unit derived from a region with an estimated population of 5.5 million was performed. Comparisons of the initial nadir creatinine, current creatinine, and renal status score (RSS) were made between those with and without urinomas. The RSS was derived from nephrology assessment of current renal status (0 = normal to 4 = end-stage renal failure or transplantation). Results were given as median (range), except for RSS, which was given as mean +/- SEM. P < or = .05 was regarded as significant.

RESULTS

During 1989-2009, 9 of 89 PUV boys were diagnosed with urinomas. Initial nadir creatinine was statistically lower in boys with urinomas (31 [18-44] vs 45 [20-574] mumol/L, P < .01). Length of follow-up was similar (5.1 [2.2-17.3] vs 5.9 [1.8-19.7] years, P = .59). Follow-up creatinine was significantly lower in urinoma boys (44 [25-77] vs 61 [29-1227] micromol/L, P < .05), as was the RSS (0.14 +/- 0.14 vs 0.91 +/- 0.14, P < .01). No urinoma boys progressed to end-stage renal failure or required transplant.

CONCLUSION

This population-based study of PUV boys demonstrates that urinomas reduce nadir creatinine and significantly protect long-term global renal function.

Furosemide nephrolithiasis causing ureteral obstruction and urinoma in a preterm neonate

Nephrolithiasis and nephrocalcinosis in low-birth-weight, preterm neonates are well-documented complications of furosemide administration. Perinephric urinomas and urinary ascites have been previously reported as complications of obstruction due to posterior urethral valves or ureteropelvic junction obstruction. We present an unusual case of furosemide-induced nephrolithiasis causing ureteral obstruction, urinoma, and acute renal failure in a preterm neonate.

Acute perirenal extravasation of urine in an infant with non-refluxing megaureter

Perirenal extravasation of urine is a rare event in congenital uropathies, mostly observed perinatally in the case of infravesical obstruction. We describe a male infant with a primary non-refluxing obstructive left megaureter who developed an acute perirenal extravasation and ascites at the age of 4 weeks. After temporary upper urinary diversion, ureterocystoneostomy was successfully performed. Intraoperatively, the distal ureter showed an extremely narrow lumen over a distance of 3 cm. In the current literature, postnatal management of primary megaureters is preferably conservative. Our patient demonstrates an extremely rare complication demanding early surgical intervention.

Urinary ascites in infancy: varied etiologies

Three cases of urinary ascites are presented, each with a different underlying aetiology. The age and modes of presentation also varied and management strategies were accordingly tailored to each patient's clinical requirements. All 3 patients survived and subsequently were discharged with good renal function. Although a rare condition, infants with urinary ascites can present as clinical emergencies in need of prompt resuscitation with subsequent drainage of the urine and decompression of the urinary tract. The ultimate management regime will vary and depend upon site of urinary extravasation and underlying aetiology.

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.