gastric strongyloides stercoralis in a patient with inflammatory myopathy

strongyloides stercoralis is a free living tropical and semitropical soil nematode which its larva penetrates skin. it can complete its life cycle in human body and causes autoinfection. most patients have no frank symptoms. but respiratory, gastrointestinal and skin manifestation may occur. we report a 76 year old man admitted to emergency room with muscle weakness, dyspnea, nausea, vomiting while receiving prednisolone 60 mg/d plus methotrexate 15 mg intramuscular injections per week for his underlying polymyositis. his upper endoscopy showed an ulcer and microscopic examination revealed s. stercoralis larvae and adult worm in gastric mucosa. he was treated with a combination of parenteral ivermectin and oral albendazole, the disease course ended in complete improvement with clearing of daily stool samples after more than 2 weeks of treatment. it is noteworthy that the pre-steroid stool examinations were negative for parasites.