[Acute pulmonary histoplasmosis with liver and lung involvement outside the endemic area--differential diagnosis]

A case of acute pulmonary histoplasmosis in a non-endemic setting is described. A 36 year-old male patient was admitted because of fever attacks, weakness and dyspnea on exertion. The chest X-ray revealed bilateral patchy and nodular consolidations and bilateral enlargement of the hilar lymph nodes. On computed tomography of the abdomen the spleen was enlarged with a longitudinal diameter of 12.7 cm. Respiratory insufficiency was demonstrated by an arterial oxygen tension (PaO2) of 7.71 kPa at rest. Pathological values of liver function tests were indicative of liver involvement. A transbronchial lung biopsy was performed. Histologic examination of the biopsy specimen revealed scattered small nonnecrotizing granulomas with epithelioid cells and multinucleated giant cells. Precipitating antibodies to Histoplasma capsulatum were detected by immunodiffusion in bronchoalveolar lavage fluid and blood, IgG antibodies to Histoplasma capsulatum yeast antigens were revealed by enzyme immunoassay. The histoplasmin skin test was negative. The pneumonitis, lymph node and spleen enlargement and the pathological liver function tests resolved within one month without treatment. The PaO2 returned to normal within one week.