[Chronic trichinosis and neuromuscular diseases. Morphologic and pathogenetic aspects]

Muscle biopsies were carried out on five patients affected by a chronic neuromuscular disorder, mostly in the form of a spinal muscle atrophy. All patients had suffered from acute trichinellosis many years before, the interval between acute parasitic infection and the appearance of the slowly progressive neuromuscular syndrome being of 21, 13, 35, 26 and 16 years respectively. In biopsy specimens, morphological and enzyme-histochemical changes typical of a progressive neurogenic muscular atrophy were present; in addition, encapsulated but still living, enzyme-positive parasites and signs of focal myositis were detected. The possible pathogenetic correlations between the "chronic" trichinellosis and the "degenerative" neuromuscular disorder are discussed.