Disseminated histoplasmosis in India is not so rare in immunocompetent patients
July 06 2015
Drs De and Nath from Kolkata describe in a recent publication seven patients - none of whom had any immunocompromised staus- who had disseminated histoplasmosis. The patients were seen over a 5 year period and had a mean age of 35 years (28 – 48 years). They presented with symptoms including prolonged fever, weight loss, anaemia or pancytopenia and hepatosplenomegaly. One patient had skin nodules and another had bilateral adrenal masses.
In all cases the diagnosis was made on bone marrow aspiration and biopsy, skin nodule biopsy or adrenal biopsy. Organisms were sparse and seen on PAS or Romanowsky staining*.
Only one patient grew Histoplasma capsulatum, from an ulcer swab. None of the patients were documented to be immunocompromised; the man with bilateral adrenal masses had presented with adrenal failure. HIV tests were negative and the mean CD4 count was 708/uL. Previous reports have suggested that 30% of patients with disseminated histoplasmosis have ulcerated lesions - but in this study only 14% had ulcerations.
The patients responded well to amphotericin B deoxycholate or itraconazole, although one died of complications of adrenal failure and another relapsed on itraconazole, requiring long term intermittent amphotericin B. A similar and larger series was reported from CMC, Vellore in 2005 by Dr Subramanian and others, although most of their patients had HIV infection and/or diabetes .
Clinicians should be aware of disseminated histoplasmosis, which is similar to visceral leishmaniasis, in India.
Histoplasma exists in mycelial form at soil temparatures, but switches to the yeast form at normal human body temparatures (37C). The fungus persists in soil particularly where bird faeces are present.
*Romanowskys Stain: a neutral stain composed of a mixture of oxidised methylene blue dyes (azure) and eosin Y. The azures are basic dyes that bind acid nuclei and result in a blue to purple color. The acid dye, eosin, is attracted to the alkaline cytoplasm, producing red coloration. Review
1. Subramanian S, Abraham OC, Rupali P, Zachariah A, Mathews MS, Mathai D.
Disseminated histoplasmosis. J Assoc Physicians India. 2005 Mar;53:185-9.