Focal segmental glomerulosclerosis secondary to subcutaneous interferon β-1a treatment in a patient with multiple sclerosis.

Interferon (IFN)-β is a first line treatment for patients with relapsing remitting multiple sclerosis (RRMS) that has been shown to decrease relapse rates, reduce magnetic resonance imaging (MRI) disease burden and possibly delay onset of disability (Arnason, 2005). There are few reports of nephrotic syndrome related to Minimal Change Disease (MCD) or Focal Segmental Glomerulosclerosis (FSGS) during treatment with IFN-α (Nishimura et al., 2002; Tola et al., 2003; Rettmar et al., 1995). There are fewer reports of nephrotic syndrome induced by IFN-β (Tola et al., 2003; Auty and Saleh, 2005; Kumasaka et al., 2006). We report a 41 year old African American woman with RRMS that developed FSGS after 3 months of treatment with IFN-β-1a 3 times weekly and review the previously published cases.