A case of Frasier syndrome achieved complete remission by cyclosporine A for steroid-resistant nephrotic syndrome.

In pediatric steroid-resistant nephrotic syndrome (SRNS), causative genetic abnormalities are now being identified. Immunosuppressive therapy is generally believed to be ineffective in treating Frasier syndrome, which is associated with genetic abnormalities. Recently, the efficacy of cyclosporine A (CyA) via a non-immunological mechanism has been reported. However, all of these reports have shown partial remission. In the present study, we report a case of nephrotic syndrome in a 1-year-old patient who was treated with CyA for SRNS. Complete remission was confirmed for 6 months, and the patient is currently in partial remission. Following confirmation of complete remission, hereditary nephrotic syndrome was not actively investigated; however, delayed secondary sexual characteristics' development led to the diagnosis of Frasier syndrome at the age of 13 years. Thus, immunosuppressive agents may have some efficacy in treating Frasier syndrome, particularly given that our patient achieved complete remission, indicating that it is worth considering administration of immunosuppressive agents for Frasier syndrome management.