Fatal misdiagnosis of progressive disseminated histoplasmosis

Abstract

Disseminated histoplasmosis is the form of a mycosis caused by the fungus Histoplasma capsulatum that mainly occurs in immunosuppressed hosts, usually with non-specific symptoms. In non-endemic areas, where the disease is rarely involved in the differential diagnosis, a delay in treatment may lead to severe medical complications. Due to the rising prevalence of disseminated histoplasmosis in these areas, a thorough medical history is regarded as the decisive factor in prompt diagnosis of the disease. We, herein, report the case of an immunocompetent Greek farmer with disseminated histoplasmosis whose condition was initially misdiagnosed, and the consequential inadequate treatment led to his death.

Keywords: Arthritis; Differential diagnosis; Disseminated histoplasmosis; Erythema nodosum; Histoplasma capsulatum; Misdiagnosis; Non-endemic area.

Fig. 1

Histopathological analysis of colonic mucosa reveals inflammatory infiltrations, histiocytes and presence of yeast forms. (a) Colonic mucosa is seen with its characteristic crypts. (b) An inflammatory infiltrate with abundant lymphocytes along with clusters of histiocytes is observed in lamina propria. Numerous oval yeast forms, 2–3μm in size, are present in the cytoplasm of histiocytes. Scale = 200μm.

Fig. 2

Positive staining of oval yeast forms within histiocytes using various histological stains. Numerous oval yeast forms present in the cytoplasm of histiocytes are stained positively with (a) Hematoxylin Eosin, (b) Giemsa, (c) Gomori- Methenamine- Silver (GMS) and (d) Periodic Acid Schiff (PAS) stains. Scale = 100μm.