Unexplained CD4-positive T-cell deficiency in non-HIV patients presenting as a Pneumocystis carinii pneumonia

Three cases of Pneumocystis carinii pneumonia occurring in adults with unexplained T-cell defects are reported. No HIV markers were found during the follow up, and neither was any immunosuppressive disease. The authors emphasize the possibility that Pneumocystis pneumonia may occur and may be treated successfully in previously healthy subjects.