Myositis during Borrelia burgdorferi infection (Lyme disease).

Abstract
During the second stage of an illness caused by Borrelia burgdorferi, a young woman developed a myopathic syndrome characterized by severe muscular pains, incapacitating weakness of the proximal limb and the neck, as well as the bulbar muscles and elevated serum CK levels. Muscle biopsy revealed a non-inflammatory necrotizing myopathy. B. burgdorferi infection was confirmed by a considerable rise of specific IgG antibodies. A course of high dose steroids alleviated the myalgias, but paresis began to improve only after treatment with antibiotics. Our observations confirm that B. burgdorferi can cause, through an undetermined mechanism, a necrotizing myopathy, in addition to the wide spectrum of already known neurological complications.