Clinical Picture of Pneumocystis jiroveci Pneumonia in Cancer Patients

BackgroundPneumocystis pneumonia (PCP) is common in patients with HIV infection but may also occur in patients with other causes of immunodeficiency, including hematologic and solid malignancies.MethodsTo better describe the clinical picture of PCP as to maintain a high level of suspicion in adequate cases, we studied 56 cancer patients with PCP and compared them to 56 cancer patients with bacterial pneumonia.ResultsAmong 56 PCP patients, 44 patients (78.6%) had hematologic malignancies (18 recipients of bone marrow transplantation) and 12 patients had solid tumors. The time since diagnosis was 24 months (range, 4 to 49 months). All patients with solid tumors and 20 patients (45.4%) with hematologic malignancies were receiving steroids. Only six patients were receiving PCP prophylaxis. The main symptoms were fever (85.7%), dyspnea (78.6%), and cough (57.1%). Time from symptom onset was 7 days (range, 3 to 14 days). PCP presented as severe pneumonia (Pao2, 58 mm Hg [range, 50 to 70 mm Hg]) with bilateral interstitial infiltrates (80.4%) and bilateral ground-glass attenuation (89.3%) by CT. Of the 24 ICU patients (42.9%), 16 patients (19.6%) required mechanical ventilation. Eleven patients (19.6%) died. Compared to 56 patients with bacterial pneumonia, PCP patients were more likely to have non-Hodgkin lymphoma and be receiving long-term steroids; they had longer times since diagnosis, longer symptom duration, higher frequencies of fever and of diffuse lung disease (diffuse crackles, bilateral infiltrates, and hypoxemia), higher frequency of ground-glass opacities, and lower frequency of pleural involvement.ConclusionsPCP presents as subacute, febrile, hypoxemic, and diffuse pulmonary involvement in patients with solid tumors or hematologic malignancies receiving long-term steroids.