The case of infectious. Chronic disseminated histoplasmosis in a non-immunosuppressed patient

Abstract

Histoplasmosis a disorder of the New World is acquired by inhalation of the propagules produced by the fungus Histoplasma capsulatum. It is charaeterized by primary pulmonary involvement that promptly disseminates to other organs. The infection is mostly subclinical but can produce minor symptoms. A 35 year-old male with no pathological records, consulted because of general malaise, weight loss and non-productive cough of 3 months duration. Two mucocutaneous lesions were also observed. Laboratory tests gave normal results, and the lungs X-rays revealed only minor interstitial infiltrates and a slight involvement of the hilar region. Search for acid fast bacilli proved negative; a bronchoscopy and a biopsy of the extenal lesions were performed. Results of the latter revealed yeast cells compatible with H capsulatum. Subsequently, cultures were positive for this fungus. With the diagnosis of chronic disseminated histoplasmosis (CDR), treatment with ketoconazole, 200 mg BID was initiated. The patient responded and 8 months after diagnosis, he improved markedly. CDR is seen regularly in the inmunocompetent adult but its resemblance with tuberculosis leads to misdiagnosis. Consequently, the mycosis should be considered in the respiratory symptomatic adult patient.