Introduction

Strongyloides stercoralis is a parasite endemic of tropical and subtropical regions, with the capacity of completing its life cycle within its host through an auto-infective cycle. The low level of suspicion for the diagnosis of strongyloidiasis can lead physicians to miss or delay the final diagnosis.¹

Case report

A 76-year-old male, resident of São Paulo, Brazil, was referred to the hospital in May 2014, with a 2-month history of nausea, vomiting, anorexia, and 10-lb weight loss. Past medical history of metastatic castration-resistant prostate cancer, with recent palliative treatment with chemotherapy, and corticosteroids.

Laboratory tests during admission revealed mild anemia (hemoglobin: 11.1 mg/dL), normal total leukocyte count, normal peripheral blood eosinophil count and an increased C-reactive protein. Upper gastrointestinal endoscopy (UGE) showed gastric mucosal erythema, areas of atrophy, intestinal metaplasia, and pyloric stenosis due to cicatricial retraction. Duodenal mucosa presented a crispy surface with enlarged and rigid villosities, diffuse erythema, edema and friability (Figures 1 and 2). Biopsy from duodenum revealed larval form of Strongyloides stercoralis in mucosal crypts (Figure 3). Patient was treated with ivermectin for 2 days, and with high doses of proton pump inhibitors (PPI).

FIGURE 1 Severe bulbo-duodenitis with mild diffuse bleeding. 

FIGURE 2 At close inspection with narrow-band imaging (NBI), enlarged and rigid duodenal villosities are seen. 

FIGURE 3 Duodenal biopsy showing Strongyloides stercoralis larval infection in the mucosal crypts (arrow) (HE). 

During hospitalization, he presented massive melena and hemorrhagic shock. Fluids and blood transfusion were started. UGE repeated during the gastrointestinal bleeding showed diffuse hemorrhagic duodenitis and bleeding erosions, which were endoscopically treated with argon plasma coagulation and hemoclips. Patient died after 11 days of hospitalization from Strongyloides stercoralis hyperinfection syndrome and sepsis.

Discussion

Strongyloidiasis is often an asymptomatic infection of upper small intestine. Immunosuppression may lead to hyperinfection with dissemination of S. stercoralis to almost all organs, with bacterial sepsis.² The hyperinfection syndrome is frequently associated with corticosteroid administration, and other immunosuppressive conditions, such as malignancies.³ This disease is potentially lethal, with mortality rates up to 87%, and it is characterized by gastrointestinal and/or pulmonary involvement.⁴Clinical manifestations of gastrointestinal impairment include abdominal pain, diarrhea, bleeding, nausea and vomiting. Diagnosis is challenging due to non-specific clinical features, and can be done by biopsy of suspicious changes at upper endoscopy.⁵