Early recognition of gonadal dysgenesis in congenital nephrotic syndrome

Mutation of the Wilms tumor suppressor gene (WT1) has been recognized as one of the etiologies of steroid-resistant nephrotic syndrome (SRNS). The mutation is also responsible for gonadal dysgenesis in 46,XY individuals. Early recognition of the presence of Y chromosome is of particular importance because of the high risk of gonadal tumor. We present here three cases of steroid-resistant nephrotic syndrome with WT1 mutation and 46,XY karyotype. Patient 1 and 2 have intron splice site (IVS9+5G > A) mutation. Patient 3 has c.1301G>A (p. R434H) mutation. All cases had normal female external genitalia at birth and eluded the diagnosis of gonadal dysgenesis until later in life. We suggest that chromosomal analysis should be promptly performed in female patients with early-onset steroid-resistant nephrotic syndrome.