[Pathologic observations on the peripheral nerves in simple polymyositis].

In 6 cases of polymyositis was performed muscle and sural nerve biopsy. All the 6 patients presented typical clinical pictures of simple polymyositis. Sural nerves showed demyelination and axonal changes, under light and electron microscopy. It seems that simple polymyositis accompanied by the alterations in peripheral nerves is not very rare. In 3 cases, a few small arteries in the interfascicular areas of the nerves were nearly totally occluded due to the intimal proliferation. Clinical examination revealed no evidence of systemic vasculitis. On the basis of these data, the authors suspect that the above mentioned pathological findings probably are partial presentations among the spectrum of allergic disorder, which presents many clinical types and various combinations.