Early Detection of Schistosoma Egg-Induced Pulmonary Granulomas in a Returning Traveler

Abstract

We report the case of a French traveler who developed acute pulmonary schistosomiasis 2 months after visiting Benin. He presented with a 1-month history of fever, cough, and thoracic pain. Initial investigations revealed hypereosinophilia and multiple nodular lesions on chest computed tomography scan. Lung biopsies were performed 2 months later because of migrating chest infiltrates and increasing eosinophilia. Histological examination showed schistosomal egg-induced pulmonary granulomas with ova exhibiting a prominent terminal spine, resembling Schistosoma haematobium. However, egg shells were Ziehl-Neelsen positive, raising the possibility of a Schistosoma intercalatum or a Schistosoma guineensis infection. Moreover, involvement of highly infectious hybrid species cannot be excluded considering the atypical early pulmonary oviposition. This case is remarkable because of the rarity of pulmonary schistosomiasis, its peculiar clinical presentation and difficulties in making species identification. It also emphasizes the need to consider schistosomiasis diagnosis in all potentially exposed travelers with compatible symptoms.

Figure 1.

Computed tomography scan of the chest (axial plane) showing a well-defined lung nodule in the right lung.

Figure 2.

Histological examination of a biopsy specimen from a lung lesion. (A) Schistosoma egg surrounded by granulomatous inflammation and eosinophilic reaction (hematoxylin and eosin stain, magnification ×100); (B) Schistosoma egg exhibiting a prominent terminal spine (hematoxylin and eosin stain, magnification ×400); (C) strongly positive acid-fast egg's shell (modified Ziehl–Neelsen stain, magnification ×400).