Retroperitoneal Cystic Lesion in Pregnancy Due to a Mega Ureter

Abstract

Mega ureter can be divided into Primary and secondary mega ureter (PMU & SMU). Rarely PMU can present during pregnancy as non-obstructed, non-refluxing or as refluxing obstructed mega ureter. We report a case of mega ureter which incidentally found during pregnancy. Case: 23yr old, previously healthy primi gravida presented for the routine dating scan at 12th weeks of gestation was found to have a right sided unilocular large retroperitoneal cystic lesion filled with anechoic fluid. Rest of the scan findings were normal. She was asymptomatic except for usual pregnancy symptoms. Further evaluation confirmed presence of right sided mega ureter. She was managed conservatively together with Genitourinary surgical team. She was induced at term and had to undergo emergency caesarean delivery due to fetal distress. She was planned to review with CTIVU after six weeks. Discussion: Crucial point in management is to differentiate PMU from SMU. Differential diagnoses are peripelvic cyst, congenital megacalyces, calyceal diverticula and capacious extra renal pelvis. Ordinary IVU or CT-IVU, MCUG will help to demonstrate reflux of urine at vesico-ureteral junction but can’t be done during early pregnancy due to radiation to the fetus. Proper management should be done once the body physiology normalizes following delivery. Patients should be regularly screened and advised on prevention of UTI. Delivery should be planned via a multi-disciplinary team discussion. Conclusion: Even though asymptomatic mega ureter in pregnancy doesn’t need treatment, patients should be kept under careful surveillance for the complications. Definitive treatment should be offered following delivery.