Fatal pneumocystis jiroveci pneumonia in ABVD-treated Hodgkin lymphoma patients

Dear Editor, Lung infections are serious complications in patients with hematological malignancies [1–4]. Pneumocystis jiroveci is an important causative organism. T cell deficiency and preceding corticosteroid therapy are important risk factors for Pneumocystis jiroveci pneumonia (PCP). The course of PCP may be fulminant and in patients who require mechanical ventilation, the prognosis is poor. When PCP was identified as one of the most important severe infections in children aggressively treated for acute lymphoblastic leukemia in the 1970s, cotrimoxazole was introduced as the drug of choice for therapy as well as for prophylaxis [5]. However, the precise degree of immunosuppression at which PCP may occur is still not fully elucidated. Thus, we are still not able to identify patients who would benefit from prophylaxis with a satisfactory accuracy [1, 3, 6]. We identified several patients with severe PCP belonging to patient categories not generally recommended to be treated with prophylactic cotrimoxazole. Based on this observation, we decided to investigate PCP among a spectrum of patients with hematological malignancies at our center during an 8-year period. The main objective was to further characterize patients who would have benefited from prophylaxis. At the Department of Hematology, Karolinska University Hospital Solna, all categories of hematological malignancies/ disorders are treated. Patients with new or increasing pulmonary infiltrates are usually examined by both thoracic computerized tomography and bronchoscopy with extensive sampling for possible causative microbial pathogens. Bronchoscopy is avoided in patients who are considered not to tolerate this procedure due to comorbidity, hypoxemia or severe thrombocytopenia. All results from P.jiroveci testing during the years 1999– 2006 were retrospectively retrieved from the Swedish Institute for Infectious Disease Control. The specimens have been examined by immunofluorescence (IFL) by use of monocolonal antibodies [7]. Patients with a positive result by IFL treated at our center were identified and their clinical charts reviewed. The study was approved by the local ethics committee. P.jiroveci was identified by IFL on bronchoscopically obtained secretions in 31 patients, and by IFL on sputum or nasopharyngeal secretions in nine and one patient, respectively. All patients had abnormal findings on chest X-ray (36/38) or CT (26/26). A total of 41 patients (40 with a hematological malignancy and one with a severe autoimmune hemolytic anemia) with PCP were identified during the 8 year-period. Their median age was 62 years (range 23-83 years; Table 1). None of the patients had received PCP prophylaxis. The large majority of patients (95%) had a lymphoproliferative malignancy (Table 1). Twenty-three patients (56%) had progressive disease and four of the eight Hodgkin lymphoma patients, including one patient with a concomitant myeloma, succumbed to PCP. M. Kalin Department of Medicine, Division of Infectious Diseases, Karolinska University Hospital Solna and Institutet, Stockholm, Sweden