Fulminant disseminated strongyloidiasis mimicking inflammatory bowel disease: a case report

Strongyloidiasis is a gastrointestinal parasitic infection caused by Strongyloides stercoralis (S. stercoralis). Its autoinfection capability allows the parasite to persist lifelong in the absence of treatment, exposing patients to the risk of hyperinfection and fatal dissemination in cases of immunosuppression.

A 33-year-old man, presented in December 2024 with severe acute colitis. Endoscopy and histopathology findings were consistent with inflammatory bowel disease (IBD). The patient was treated with intravenous corticosteroids and antibiotics, then maintained on tapering oral corticosteroids. Three months later, while on 20 mg/day prednisone equivalent, he was readmitted for another episode of severe acute colitis. Stool parasitology, stool culture, tissue cytomegalovirus (CMV) polymerase chain reaction (PCR), and Clostridium difficile toxin assays were all negative. Intravenous corticosteroids were restarted with partial response. The patient subsequently developed Enterococcus faecium meningitis, ileal obstruction requiring surgical resection, and hypoxemic respiratory distress. Gastric biopsies revealed numerous Strongyloides larvae. Stool parasitology confirmed disseminated strongyloidiasis. The clinical course rapidly deteriorated to septic shock and multiorgan failure, causing death.

This case highlights the potential diagnostic confusion between IBD and strongyloidiasis. It underscores the potentially fatal consequences of unrecognized chronic strongyloidiasis and supports systematic screening prior to immunosuppressive therapy in at-risk populations.