Enterococcal meningitis associated with Strongyloides infection: a case report and literature review

Abstract

Strongyloides stercoralis is an intestinal nematode endemic throughout tropical and subtropical areas, with a life cycle consisting of free-living and parasitic components. Unlike other soil-transmitted nematodes, it is capable of self-infection, which can cause chronic disease that lasts for decades, or cause overwhelming hyperinfection in people taking corticosteroids or other immunosuppressive drugs or who have impaired Th2 cell-mediated immunity, particularly those infected with human T-lymphotropic virus 1. During hyperinfection, a large numbers of larvae have access to the bloodstream, lungs, central nervous system, and other organs. Bacteremia and polymicrobial meningitis can occur due to disruption of the intestinal mucosa and the presence of bacteria on the surface of foreign larvae. Enterococcal meningitis for instance may occur concurrently with strongyloidiasis as a consequence of haematogenous dissemination. We present a clinical case of a 45-year-old, man from Bangladesh, in which co-infection occurred. The patient was not immunocompromized and had no apparent risk factors, which represents the unusual aspect of this case report. A literature review on enterococcal meningitis and Strongyloides coinfection in adult patients was performed encountering 21 cases. Cases have been reviewed and discussed. Clinicians may suspect S. stercoralis co-infection when identifying an enterococcal meningitis in adult patients coming from endemic areas.

Keywords: Enterococcus; Strongyloides; central nervous system; epidemiology; meningitis; parasitic disease; strongiloydiasis.

Figure 1

Image of the colonoscopy-mucosal edema and aphthous ulcers along the colon.

Figure 2

a) Histology of the colon mucosa. haematoxylin and eosin (H&E), original magnification x 200. Three parasites are visible within the intestinal crypts. The lamina propria shows a polymorphous inflammatory infiltrate containing numerous eosinophils; b) - Histology of the colon mucosa. H&E, original magnification x 200. The lamina propria shows a moderate inflammatory infiltrate including numerous eosinophils and a small granuloma in formation.

Figure 3

Disseminated strongyloidiasis is characterized by diffusion of gut flora into the bloodstream, leading to bacteremia.