A Case of Polymyositis with Severe Gastrointestinal Bleeding Due to Strongyloidiasis

Abstract

A 78-year-old man presented with fatigue and muscle weakness. His serum creatine kinase level was elevated and an electromyogram showed myogenic conversion. He was diagnosed as having polymyositis. Whole-body computed tomography and an endoscopic study ruled out malignancy. He was prescribed 55mg of prednisolone (1mg/kg/day) and soon thereafter his muscle strength returned to normal. However, while on the steroid, he developed diarrhea. Fecal culture and a Clostridium difficile antigen test were negative. Nonetheless, he was prescribed metronidazole, 1,000mg, twice daily, as empirical therapy for C. difficile infection. His diarrhea progressively worsened, resulting in massive melena, shock, and a fever of 39℃. A subsequent blood culture was positive for Escherichia coli. He was started on 3g meropenem/day together with fluid and blood transfusions. An upper gastric endoscopy repeated during gastrointestinal bleeding showed diffuse hemorrhagic duodenitis and bleeding erosions. Duodenal biopsy showed strongyloidiasis. After treatment with 12mg ivermectin once every 2 weeks his fecal test remained positive；he was therefore started on a daily dose of ivermectin and albendazole. Despite treatment, he died from gastrointestinal bleeding. The autopsy revealed no evidence of active strongyloidiasis infection. This case demonstrates that, even with successful treatment, the complications of strongyloidiasis, especially gastrointestinal bleeding, can cause death. Thus, in Japan, based on epidemiologic trends, patients who have to undergo strong immunosuppressive therapy, including large doses of steroids for rheumatic disease, should be screened and prophylactically treated for Strongyloides stercoralis infection.