Progressive disseminated histoplasmosis presenting with cachexia and hypercalcemia

Abstract

Histoplasmosis is a common endemic mycosis. The majority of infections involving this dimorphic fungus are asymptomatic. Manifestations in symptomatic patients are diverse, ranging from flu-like illness to a more serious disseminated disease. We present here a case of chronic disseminated histoplasmosis mimicking a metastatic cancer. We reviewed the literature for cases of disseminated histoplasmosis presenting with hypercalcemia, focusing particularly on clinical presentation, risk factors predisposing for fungal infection, and outcome. We report a case of a 65-year-old diabetic male who presented with unexplained weight loss and hypercalcemia. Multiple brain space-occupying lesions and bilateral adrenal enlargement were evident on imaging studies. Biopsies showed caseating granulomas with budding yeast, consistent with histoplasmosis. The patient's symptoms resolved after liposomal amphotericin B and itraconazole therapy. Granulomatous diseases, including fungal infections, should be considered alongside malignancies, in patients with similar presentation.

Keywords: disseminated histoplasmosis; hypercalcemia.

Figure 1

Computed tomography of the abdomen showing enlarged adrenal glands, the left gland measured 6.8 × 6.7 × 2.7 cm.

Figure 2

Brain magnetic resonance imaging (flare) showing three lesions in the left frontal, temporal, and occipital lobes.

Figure 3

Adrenal needle biopsy section stained with hematoxylin and eosin showing necrotizing granuloma (original magnification, 10×).

Figure 4

Adrenal needle biopsy section stained with hematoxylin and eosin showing granulomatous inflammation and a multinucleated giant cell containing small yeast surrounded by halos representing fungal capsules (original magnification, 20×).

Figure 5

Adrenal needle biopsy section stained with Gomori methenamine silver showing small oval budding yeast typical of Histoplasma capsulatum (original magnification, 40×).