RESUMEN
A case of Strongyloides stercoralis hyperinfection in a patient with dermatomyositis and diabetes mellitus is herein reported. The case was a 60-year-old female admitted due to watery diarrhea and unconsciousness. She had a 10-year history of chronic immunosuppressive therapy including methotrexate and prednisolone for dermatomyositis. Stool parasitological examination revealed numerous rhabditiform larvae of threadworm "S. stercoralis." Larva in stool sample was characterized by sequencing of mitochondrial DNA. After treatment with ivermectin, the patient recovered without evidence of S. stercoralis in follow-up stool samples. In endemic areas, stool examination for detection of S. stercoralis should be performed on a regular basis for all patients receiving immunosuppressive therapy, as early detection and treatment are necessary to minimize complications of severe strongyloidiasis.