Background: Pneumocystis carinii pneumonia (PCP) occurs in immunocompromised patients without the acquired immunodeficiency syndrome (AIDS). There has been an increasing yearly number of cases of PCP in our patients without AIDS.
Objective: To determine the nature of the underlying disorder and previous immunosuppressive treatment in patients with PCP without AIDS.
Method: A study of the charts of 78 such patients admitted to our hospital from 1980 through 1993.
Results: The number of PCP cases per year increased during the period studied. All patients had an underlying disorder, either hematologic malignancy (49%), solid organ tumor (4%), vasculitis or other immunologic disorder (22%), or they had undergone renal transplantation (17%) or bone marrow transplantation (9%). Previous immunosuppressive medication consisted of prednisone or other corticosteroids in 72 (92%) of 78 patients, cytotoxic drugs in 55 (71%) of 78 patients, both in 50 (64%) of 78 patients, and none in one patient. Quantification of previous corticosteroid treatment showed a large variability among patients. The overall mortality rate for patients was 35% (27/78). Mortality was significantly higher in patients with a concomitant pulmonary infection (P = .01), an underlying disorder other than that which resulted in renal transplantation (P = .03), mechanical ventilation (P < .001), previous chemotherapy (P = .04), as well as previous cyclophosphamide treatment (P = .01). A trend toward a higher mortality in patients with previous corticosteroid use was detected (P = .06).
Conclusion: Pneumocystis carinii pneumonia may complicate a variety of immunocompromised states, with considerable mortality. Pneumocystis carinii pneumonia occurred at all levels of immunosuppression; no threshold level could be defined.