The article by Mahaffey et al1 on coccidioidomycosis in patients with acquired immunodeficiency syndrome (AIDS) and Pneumocystis carinii pneumonia (PCP) illustrates the difficulties one may encounter when managing PCP in patients with AIDS. Their two patients presented with typical PCP, had a thorough evaluation for other opportunistic infections (including bronchoalveolar lavage), and were given standard PCP treatment that included corticosteroids. After initial improvement, these patients became sicker (and one died) because of simultaneous and unrecognized coccidioidomycosis that was diagnosed only after culture preparations became positive weeks later.
Patients with AIDS may have simultaneous lung infections with two or more pathogens. Patients with AIDS may have concurrent PCP and histoplasmosis.2 As in coccidioidomycosis, histoplasmosis is often diagnosed after some delay because cultures grow slowly. If infected with both Pneumocystis and Histoplasma, and if corticosteroid therapy is given for PCP (diagnosed quickly by stain of sputum or bronchoalveolar lavage fluid),