The patient was commenced on the COCP before discharge to prevent further periods. She also had a short course of antibiotics due to an episode of pyrexia and a raised CRP.

She was referred to the tertiary gynecological center for definitive management.

This is a very unusual case of a complex congenital abnormality. Renal anomalies are not unusual with Mullerian duct abnormalities (e.g. OHVIRA syndrome), but less common with lower vaginal atresia (which in itself is rare).

OHVIRA syndrome was initially suspected based on the ultrasound appearances (hematometrocolpos and multicystic dysplastic right kidney), but the renal anomaly is actually due to an ectopic ureter inserting into the obstructed cervix/upper vagina. An ectopic ureter usually leads to issues with continence in girls, as urine drains via the vagina. In this case as the upper vagina was obstructed, the kidney presumably became obstructed and dysplastic as there was no route for drainage. Antenatal imaging was not available, but there were no recorded concerns of renal anomalies, and no history of UTIs as an infant.

Hematometrocolpos is an uncommon but important cause for acute lower abdominal pain in girls of this age. This case demonstrates the importance of the clinical history (the cyclical nature of the pelvic pain was not recorded by the clinical team on the ultrasound request, nor was the menstrual history). Unfortunately, due to patient discomfort, it was difficult to delineate the anatomy on ultrasound, but the MRI demonstrates it clearly.