Inflammation and response to steroid treatment in limb-girdle muscular dystrophy 2I

Limb-girdle muscular dystrophy (LGMD) type 21, caused by mutations in the fukutin-related protein gene (FKRP), is one of the most common forms of LGMD in childhood. We describe two patients with LGMD21 and a Duchenne-like phenotype. in addition to the common L2761 mutation, both patients had a new mutation in FKRP, L169P and P89L, respectively Clinical onset was triggered by viral upper respiratory tract infections. In addition to the common dystrophic pattern with a weak immune histochemical staining for a-dystroglycan, muscle biopsy showed inflammatory changes. This was especially striking in one of the patients with up-regulation of MHC class 1 antigen, suggestive of myositis. Both patients showed a good clinical response to treatment with prednisolone, which was initiated at daily dosage of 0.35 mg/kg/day. Our results provide evidence for an inflammatory involvement in the pathological expression of LGMD21 and open up the possibility that this disorder could be treatable with corticosteroids. (C) 2007 European Paediatric Neurology Society. Published by Elsevier Ltd. All rights reserved.