Direct morphological identification of Borrelia burgdorferi in the muscle biopsies: the possibility of association of the neuromuscular abnormalities with Borreliosis

The authors examined 40 muscle biopsy specimens taken from patients with neuromuscular symptoms when the diagnosis was unestablished or presumptive. Eighteen of them exhibited foci of muscle fiber damage with the presence of spirochete-like structures in the semithin tissue sections. Electron microscopy of these areas detected Borrelia as vegetative and diverse L-forms. Immunocytochemical techniques usingantibodies to Borrelia burgdorferi antigens confirmed that the spirochetes belonged to this species. This allows one to consider borreliosis as an etiological or complicating factor of neuromuscular pathology and to recommend the above morphological methods for the diagnosis of neuromuscular diseases of unknown origin.