Strongyloides stercoralis ileitis detected by double-balloon endoscopy

A 52-year-old man was admitted for chronic diarrhea since more than a year, and progressive low-leg edema over the past three months. His history revealed that he made several short-term trips to southern China for business. He was passing loose stool seven to eight times every day. Laboratory tests revealed a total leukocyte count of 10.5 × 10⁹/L with 59.7 % neutrophils, 1.5 % eosinophils, and 30 % lymphocytes. His serum albumin level was 11.5 g/L and serum IgE level was 739 IU/mL (normal range < 78 IU/mL). The serum human immunodeficiency virus (HIV) antibody status was negative. Small-intestine follow-through study showed long-segment narrowing of the lumen of the terminal ileum ([Fig. 1 a]), whereas abdominal computed tomography demonstrated diffuse wall thickening of the terminal ileum ([Fig. 1 b]). Double-balloon enteroscopy was carried out via the anal route to further explore the long-segment narrowing in the ileum. There was loss of the normal villous structure of the terminal ileum on washing with water ([Fig. 2 a]), and widespread swelling and erosions with petechiae were noted in the mucosa after air inflation ([Fig. 2 b]; [Video 1]). Histopathological examination of biopsy specimens of this area revealed marked leukocytic infiltration, with eosinophils in the lamina propria ([Fig. 3 a]). Parasitic ova and larvae, morphologically resembling the filariform larvae of Strongyloides stercoralis, were found within the intestinal crypts ([Fig. 3 b]). The patient subsequently received treatment with ivermectin (12 mg/day) for 3 days. The diarrhea gradually resolved and the serum albumin level rose to 31.2 g/L 4 months after drug treatment.

Fig. 1 Small-intestine series and abdominal computed tomography demonstrating diffuse wall thickening of the terminal ileum.

Fig. 2 a Double-balloon enteroscopy showing disappearance of villi in the terminal ileum under water. b Air inflation revealed widespread swollen and erosive mucosa with petechiae.

Fig. 3 a Eosinophils infiltrating the lamina propria. b Parasitic ova and larvae resembling the filariform larvae of S. stercoralis within the intestinal crypts.

Video 1 Washing of the terminal ileum with water revealing loss of the normal villous structure.

Endoscopy_UCTN_Code_CCL_1AC_2AG