Abstract
Autosomal recessive steroid-resistant nephrotic syndrome (NS) is a rare, genetically determined nephropathy caused mainly by a mutation in the NPHS2 gene. This type of NS is usually resistant to other immunosuppressive therapy as well, but a few cases of cyclosporine A-induced partial remission of inherited NS have been reported.
We present a boy that developed NS at the age of 18 months. There was no decrease of proteinuria on standard prednisolone therapy, and a diagnosis of steroid-resistant NS was established.
However, the proteinuria decreased significantly following the initiation of cyclosporine A therapy (from 1280 to 380 mg/m(2) per day) without any negative effects on renal function (stable glomerular filtration rate 130-150 ml/min per 1.73 m(2)). The molecular genetic test revealed a homozygous R138Q mutation in the NPHS2 gene.
Our case demonstrates that cyclosporine A can induce partial remission in patients with genetic forms of NS without influencing the glomerular filtration rate.