Comparison of clinical and radiological features of pneumocystis pneumonia between malignancy cases and acquired immunodeficiency syndrome cases: a multicenter study.

BACKGROUND The clinical features of pneumocystis pneumonia (PCP) differ according to the predisposing factors responsible for immunosuppression. Although PCP in patients with acquired immunodeficiency syndrome (AIDS) has been extensively described, its characteristics in non-AIDS patients, such as those with malignancies, are not thoroughly documented. STUDY OBJECTIVE To characterize and compare the clinical and imaging features of PCP in patients with malignancies with those in AIDS patients. DESIGN A multi-center retrospective study. PATIENTS AND MEASUREMENTS We evaluated the clinical and radiological features of PCP in 21 patients with malignancies and in 17 with AIDS. Clinical presentation, serum markers, oxygenation, CT findings, and outcome were examined. RESULTS The patients with malignancies showed shorter durations of symptoms before PCP was diagnosed. The levels of serum markers and the oxygenation index did not differ. CT showed diffuse or widespread ground-glass opacity (GGO) in all of the patients evaluated. None of the AIDS patients demonstrated consolidation, whereas half of the patients with malignancy showed consolidation along with GGO. The extent of GGO scored on CT images was significantly greater in the AIDS patients. No correlation was observed between the CT findings and other clinical parameters. All of the AIDS patients recovered from PCP, whereas six patients with malignancies died within a month after the onset of PCP. CONCLUSION The characteristics of the CT images differed between the patient groups with different underlying disorders, although it remains to be determined whether CT findings are associated with other clinical features or are predictive of the outcome of PCP.