Cystic adnexal mass in a 16-year-old female: Ovarian pathology or complication of a Müllerian anomaly?

Patient: Female, 16 Final Diagnosis: Pelvic mass Symptoms: None Medication: None Clinical Procedure: CT • MRI Specialty: Diagnostic radiology • pediatrics OBJECTIVE: Unusual presentation of unknown etiology, Rare disease, Mistake in diagnosis BACKGROUND: Müllerian anomalies encompass a wide variety of malformations in the female genital tract, usually associated with renal and anorectal malformations. Of these anomalies, approximately 11% are uterus didelphys, which occurs when midline fusion of the müllerian ducts is arrested to a variable extent. CASE REPORT: We report the case of a 16-year-old female with uterine didelphys, jejunal malrotation, hematometra, hematosalpinx, and bilateral subcentimeter homogenous circular cystic-like renal lesions, who initially presented with left lower quadrant abdominal pain, non-bloody vomiting, and a history of irregular menstrual periods. Initial CT was confusing for an adnexal cystic mass, but further imaging disclosed the above müllerian anomalies. CONCLUSIONS: Müllerian anomalies may mimic other, more common, adnexal lesions; thus, adequate evaluation of suspicious cystic adnexal masses with multiple and advanced imaging modalities such as MRI is essential for adequate diagnosis and management.