The patient subsequently underwent laparotomy and drainage of the lesion, which was purulent. Histology confirmed an abscess with no malignant features. Hydronephrosis subsequently resolved.
The final diagnosis was an infected giant prostatic utricle cyst / abscess. Giant utricle cysts are rare occurrences in neonates 1, particularly at this size, with infected utricle cysts even less common. UTI is the most likely cause of the initial infection, and the spectrum of findings overlaps with neonatal prostatic abscesses, although there is a paucity of cases in the literature 2.