Genetic Testing Proves Crucial in Case of Ambiguous Genitalia and Renal Masses

Objective: The Denys-Drash syndrome consists of a triad of ambiguous genitalia, Wilm's tumor and nephrotic syndrome. Methods: We present a diagnostically challenging case of an XY patient with female appearance and Müllerian structures with a WT1 mutation. Results: These genetic findings resulted in gonadal dysgenesis, end-stage renal disease, and precursor changes to Wilm's tumor in both kidneys. Genetic testing proved critical in this case, helping to solidify a diagnosis and guiding our decision to proceed with bilateral nephrectomy and bilateral gonadectomy. Conclusions: Denys-Drash syndrome can present quite dramatically. WT1 testing should be considered early in the workup for patients with differences of sexual development, particularly those with 46XY karyotype.