ABSTRACT
Answer: (b) A urogenital sinus abnormality is present when the urethra and vagina are joined and exit the perineum as a common channel. A persistent cloaca or cloacal anomaly exists when a single perineal opening drains the bladder, vagina, and rectum. Patients with urogenital sinus anomalies commonly have abnormalities of the clitoris, labia, and external genitalia. A thorough medical evaluation of the newborn with a urogenital sinus should be completed as many of these children will have congenital adrenal hyperplasia (CAH). Delays in diagnosis can lead to life-threatening fluid and electrolyte abnormalities. In addition to abdominal and pelvic sonography, all patients should undergo contrast genitography to help define the length of the common sinus and the level of confluence.
