Pneumocystis carinii pneumonia in patients without HIV infection

Pneumocystis carinii is an important, but sporadic, opportunistic pulmonary pathogen in immunosuppressed HIV seronegative persons. Historically, patie nts at highest risk for P carinii pneumonia are included infants with sever e malnutrition, children with primary immunodeficiencies, patients with hem atological malignancies, and recipients of solid organ or bone marrow trans plants. Recently, solid tumor patients, in particular those receiving high- dose corticosteroids for brain neoplasms, and patients with inflammatory or collagen-vascular disorders, especially patients with Wegener granulomatos is receiving immunosuppressive therapy, have been identified as subgroups a t increased risk for P carinii pneumonia. Other factors associated with P c arinii pneumonia include the intensity of the immunosuppressive regimen and tapering doses of corticosteroids. Because P carinii pneumonia is associat ed with significant morbidity and mortality, it is important to identify hi gh-risk patient populations to administer effective chemoprophylactic agent s, such as trimethoprimsulfamethoxazole.