[Pathology of the peripheral nervous system in polyarteritis nodosa: a clinico-pathological study of two autopsy cases].

Peripheral nerves from the two autopsied cases with polyarteritis nodosa were pathologically examined. Case 1 was a seventy-year-old female, complaining of numbness and weakness of the extremities. Sensory deficits in all modality with induced dysesthesia were distributed as a mode of overlapping mononeuritis multiplex in the distal portion of extremities. Motor involvement was also noted in extremities in disarray-accentuated pattern. Extensive steroid hormone therapy was performed and remarkable improvement in clinical sign was temporarily obtained. Relapse with bowel involvement was a cause of the death. In the post-mortem examination, central fascicular degeneration with the loss of large myelinated fibers were seen at the middle portion of upper limbs in median nerve and at the lower mid-thigh in sciatic nerve. In the distal portion of those nerves, diffuse extensive loss of large myelinated fibers in the fasciculus were observed. Some of small thin myelinated fibers in the central fasciculus or distal portion of nerves were thought to be regenerated in nature. Accumulation of cell organelles in the axonal swellings were frequently occurred in the proximal to the ischemic site. Case 2 was a seventy five-year-old female with a both motor and sensory involvement in the distal extremities. Right pulmonary effusion and extensive subcutaneous hemorrhage and necrotic gangrene in the leg was also noted. Post-mortem examination of peripheral nerves revealed a presence of central fascicular degeneration in the distal sciatic nerves and nearly complete loss of myelinated fibers in the distal nerves. Ventral and dorsal roots and dorsal root ganglia were well preserved.(ABSTRACT TRUNCATED AT 250 WORDS)