[Primary megaureter]

Use of Temporary Double-J Stent Placement for Children With Congenital Hydronephrosis: A Long-Term Single-Center Cohort Study

OBJECTIVE

To evaluate the utilization of double-J stents in children with congenital hydronephrosis in order to avoid or postpone more invasive surgical intervention. Numerous studies have demonstrated that congenital hydronephrosis caused by ureteropelvic junction obstruction (UPJO) or primary obstructive megaureter (POM) may require a surgical correction in up to 20% of cases.

METHODS

All infants with severe hydronephrosis and/or an obstructive pattern on renal scintigraphy that received double-J stent placement between 2010 to 2015 in our center were analyzed. Children were followed regularly with ultrasound and received antibiotic metaphylaxis. Urinary tract infection (UTI) and double-J dislocation were defined as complications. Treatment success was defined as avoidance of surgery and reduction of hydronephrosis to grade 1 or 0 during the observation period.

RESULTS

29 children were included, in these, 34 (23 UPJO, 7 POM, 4 UPJO and POM) treatment attempts were performed. Stent implantation failed in six cases, resulting in 28 double-J stent treatments, of which 19 (69%) were successful within the follow-up period of 20 to 104 months. The most common complications were febrile UTI in 6 of29 cases and double-J dislocation in 3 of 29 cases.

CONCLUSION

During the observation period, the success rate of temporary double-J in urodynamically relevant obstruction was relatively high. However, urinary tract infections and a complex disease course due to renal stent dislocation, as well as the need for repeated anesthesia and radiation exposure, should be taken into account. Hence, we do not recommend double-J stents placement in all children with congenital hydronephrosis; it may be useful in selected cases.

Congenital Giant Megaureter in a 16-Year-Old Female Presenting With Abdominal Pain: A Case Report and Review of Literature

We describe a case of congenital giant megaureter in a 16-year-old female. She presented with a 5-day history of abdominal distention, right flank pain and tenderness. Right pyelonephritis was suspected. Computerized tomography showed a large cystic abdominal mass with no appreciably functioning left kidney causing secondary compression of the contralateral right ureter. A left upper nephroureterectomy was performed, draining over 3.5 L of fluid. Our experience suggests that congenital giant megaureter should be considered in the differential for pediatric patients presenting with a cystic abdominal mass.

Drainage-related ultrasonography (DRUS): a novel technique for discriminating obstructive and nonobstructive hydroureters in children

BACKGROUND

Despite advances in urologic imaging, the paucity of an optimal technique that accurately clarifies obstructive and nonobstructive hydroureter exists.

OBJECTIVE

This study was conducted to introduce a novel and modified ultrasonographic technique, known as drainage-related ultrasonography (DRUS), discriminating obstructive and nonobstructive, nonrefluxing hydroureter.

MATERIALS AND METHODS

A total of 358 children (mean age, 3.7 years) with 418 nonrefluxing hydroureter were included. These children were composed of two groups of obstructive nonrefluxing (141 children with 157 dilated ureters) and nonobstructive, nonrefluxing (217 children with 261 hydroureter). The definite diagnosis regarding the subtype of hydroureter was derived from appropriate investigation. The maximum diameter of the dilated ureter, which was observed on ultrasonography, was recorded before and after 3 h of catheterization, as D1 and D2, respectively. To assess the D ratio, a formula was developed, that is, [(|D1 - D2|)/D1] × 100. Values were recorded and cutoff points were set to discriminate between subtypes.

RESULTS

Obstructive versus nonobstructive subtypes of nonrefluxing hydroureter were clarified with 78.5 % sensitivity and 83.4 % specificity, by setting a cutoff point of 22 % for the D ratio. Regardless of the cutoff point assigned to the reduction in D (D2 compared with D1), DRUS revealed 93.9 % sensitivity, 80.6 % specificity, 63.2 % positive predictive value, and 97.4 % negative predictive value in discriminating upper from lower obstruction.

CONCLUSION

DRUS affords favorable results in terms of differentiating between obstructive and nonobstructive, nonrefluxing hydroureter, as well as between upper and lower obstruction in obstructive cases. It has the potential to become an efficient imaging modality in the diagnostic algorithm of hydroureter.