Antenatal Dilated Urinary Bladder

Ashish Jain, Kaushaki Shankar

Abstract

Commonly, a dilated bladder is identified antenatally on routine ultrasonographic screening any time by the end of the first trimester. This may be partial or complete, and progressive or intermittent in some cases. Chromosomal abnormalities and associated structural abnormalities in other organs may accompany this finding. In most of the cases, obstruction is the most common cause identified. In severe cases, the associated male genitalia may suggest posterior urethral valve or prune-belly syndrome, and the presence of female genitalia may suggest cloacal abnormality or megacystis-microcolon-intestinal hypoperistalsis syndrome. Rarely, this enlargement may be complicated with urinoma, urinary ascites, peritoneal calcification, and renal dysplasia. The female fetuses are more likely to have complex defects and poorer prognosis.

There are different approaches to the management of an antenatally diagnosed enlarged bladder, ranging from close follow-up and expectant management in cases that are mild and without oligohydramnios to medical termination of pregnancy in severe cases that are associated with multiple anomalies. Although antenatal interventions such as vesicocentesis and percutaneous vesicoamniotic shunting may be promising for the relief of bladder obstruction, these procedures are not commonly performed because of their highly invasive nature and the high risk of procedural complications.