Strongyloides stercoralis hyperinfection associated with impaired intestinal motility disorder

Abstract

Infection by Strongyloides stercoralis is a highly prevalent helminthiasis, which is mostly distributed in the tropical and subtropical regions of the world. Although a substantial number of cases are asymptomatic or paucisymtomatic, severe and life-threatening forms of this infection still occur and not infrequently is lately diagnosed. Gram-negative bacteria septicemia, which frequently accompanies the severe helminthiasis, contributes to the high mortality rate. Severe infection is invariably triggered by any imbalance in the host's immunity, favoring the auto-infective cycle, which increases the intraluminal parasite burden enormously. Clinical presentation of severe cases is varied, and diagnosis requires a high suspicion index. Acute abdomen has been reported in association with S. stercoralis infection, but intestinal necrosis is rarely found during the surgical approach. The authors report the case of a man who sought the emergency unit with recent onset abdominal pain. Clinical and imaging features were consistent with obstructive acute abdomen. Scattered adhesions and a necrotic ileal segment with a tiny perforation represented the surgical findings. The patient outcome was unfavorable and respiratory distress required an open lung biopsy. Both surgical specimens showed S. stercoralis infection. Unfortunately the patient underwent multiple organ failure and septicemia, and subsequently died. The authors call attention to the finding of intestinal necrosis and impaired intestinal motility disorder as possibilities for the diagnosis and risk factor, respectively, for a severe infection of S. stercoralis.

Keywords: Intestinal Diseases; Parasitic; Strongyloides stercoralis; Strongyloidiasis.

Figure 1. Gross view of the resected jejunal loop showing the transmural hemorrhagic necrosis.

Figure 2. Chest axial CT. A and B – Large ground glass opacities involving both lungs, air bronchograms, and multiple large nodules in the right lung and smaller in the left lung. Some of the nodules in the right lung are cavitated.

Figure 3. Chest CT. A – Axial plane showing multiple bilateral scattered nodules, ground glass opacity, and cavitation in the lower right lobe. B – Scattered bilateral nodules, ground glass opacities in both upper pulmonary lobes, and cavitation in the inferior right lobe.

Figure 4. Photomicrography of the lung showing in A – diffuse alveolar damage (100x). B – Subpleural well-formed granuloma (200x) and in C and D well-formed granulomas with eosinophils and S. stercoralis larvae (arrows) (400x).

Figure 5. Photomicrography of the jejunum showing in A – chronic inflammatory infiltration with eosinophils and congestion in submucosa (100x); B – detail of penetrating filariform larva of S. stercoralis surrounded by eosinophils (400x). C – Eosinophilic infiltration of muscular layer with a giant cell (400x), and D – Serosal granuloma with focal central necrosis and transversal section of larvae. Serosa is inflamed (400x).