POLYMYOSITIS CAUSED BY A NEW GENUS OF NEMATODE

We report two patients who presented with increasing malaise and myalg ia, and had biopsy-proven polymyositis. Their conditions deteriorated after corticosteroid treatment, and repeat muscle biopsies showed adul t and larval nematodes. Anthelminthic treatment was completely success ful in both cases. The infecting nematode appears to belong to a new g enus and is, to our knowledge, the first known muspiceoid nematode to infect humans. Its life cycle and the route of infection are unknown.