Histoplasma Pyomyositis in a Patient with Disseminated Histoplasmosis and Anti-Synthetase Syndrome: Case-Based Review of Literature

BACKGROUND: Histoplasmosis is an endemic mycosis caused by Histoplasma Capsulatum, a thermally dimorphic fungus with mycelial and yeast forms. Muscle involvement is infrequent in Histoplasmosis. CASE: A 49-year-old lady presented with generalized myalgia and arthritis of two-year duration, which had responded partly to glucocorticoids. The lady reported to us two years into the illness with ulcerative eyelid lesions, worsening myalgia, and painful skin nodules. Eventually, it turned out that anti-synthetase syndrome was the primary diagnosis with Histoplasma infection in the muscles, subcutaneous tissue, and eye. We herewith present the course of her illness and a review of Histoplasmosis of the muscle in literature. CONCLUSION: The differential diagnosis of painful muscle weakness is broad. Histoplasma capsulatum infection should be considered in immunosuppressed myositis patient presenting with orbital ulcers, skin nodules and worsening muscle weakness.