Uterus didelphys with obstructed hemivagina and multicystic dysplastic kidney.

Müllerian malformations include a broad range of anomalies, resulting from the incomplete formation and/or differentiation of the Müllerian ducts. The uterus didelphys with obstructed hemivagina represents the result of a lateral nonfusion of the Müllerian ducts with asymmetric obstruction, and it is almost always associated with renal agenesis. We report a case of incidental discovery of this anomaly in a 12-year-old girl during a routine renal ultrasound. A right multicystic dysplastic kidney had been detected in the prenatal and neonatal period with no evidence of uterine anomaly. Postnatal ultrasound examinations performed regularly had never detected either right renal tissue or the uterine anomaly before menarche. Hematocolpos after menarche made uterine anomaly detection easier. Magnetic resonance imaging performed to evaluate the uterine malformation detected a dysplastic right kidney. We review the present knowledge and recommendations for the diagnosis and treatment of this anomaly, and we emphasize the use of magnetic resonance imaging not only for the evaluation and classification of Müllerian malformations, but also for the detection of the persistence of renal tissue missed with other studies.