Summary

Denys-Drash syndrome is characterized by the association of diffuse mesangial sclerosis (DMS), male pseudohermaphroditism with a 46,XY karyotype, and nephroblastoma. The prevalence is unknown but approximately 150 cases have been described so far. Wilms tumour may be the first clinical manifestation of the syndrome. Diffuse mesangial sclerosis develops after birth with massive proteinuria and nephrotic syndrome. Progression to renal failure occurs within 1 to 4 years. In incomplete forms of Denys-Drash syndrome, DMS may occur in association with either male pseudohermaphroditism or nephroblastoma. Denys-Drash syndrome is usually sporadic. Constitutional mutations in the Wilms tumour predisposing gene, WT1, most of which are located in exons 8 and 9, have been described in the majority of patients with Denys-Drash syndrome. The WT1 gene encodes a zinc-finger protein, which is probably a transcription factor involved in renal and genital development. Mutations are dominant, as patients are usually heterozygous. As mutations in the WT1 gene are in most cases de novo, the risk of reoccurrence in another sibling is extremely low. Careful renal ultrasonography, looking for nephroblastoma, should be performed in any patient found to have DMS. Treatment is supportive and consists of adequate nutrition, prevention and treatment of infectious complications, and management of renal failure. The nephrotic syndrome is resistant to corticosteroids and immunosuppressive drugs but does not recur in the graft after kidney transplantation.

Expert reviewer(s)

• Dr Patrick NIAUDET