Loss of podocyte dysferlin expression is associated with minimal change nephropathy

We report a case of limb-girdle muscular dystrophy type 2B (LGMD2B) associated with minimal change disease. Immunohistochemical examination of quadriceps muscle showed a deficiency in dysferlin in sarcolemma, and dysferlin gene analysis showed 3370 G missense mutation, leading us to the diagnosis of LGMD2B. The patient also developed glomerular proteinuria. We also explored urinary protein levels in 3 other patients with dysferlinopathy and found microalbuminuria with albumin excretion of 0.14 to 0.18 g/d in 2 patients. Renal abnormalities during LGMD2B and kidney dysferlin expression have never been reported. Renal biopsy showed a lack of glomerular dysferlin expression compared with a positive immunohistochemical marking in patients with idiopathic minimal change nephropathy and healthy controls. We therefore suggest that dysferlin is present in glomeruli and may be associated with glomerular permeability.