Pneumocystis jiroveci Pneumonia in Giant Cell Arteritis: A Case Series

Objective. To describe the clinical presentation, laboratory findings, and outcome of patients with Pneumocystis jiroveci pneumonia (PCP) and biopsy-proven giant cell arteritis (GCA) seen at a tertiary referral center. Methods. Using International Classification of Diseases, Ninth Revision codes, all patients with GCA and PCP between January 1, 1976 and December 31, 2008 were identified. Medical records were reviewed. PCP was defined by the identification of Pneumocystis jiroveci organisms in the clinical setting of pneumonia. Results. We identified 7 patients with GCA (5 women and 2 men) who developed PCP (the mean +/- SD age at diagnosis was 71.6 +/- 6.1 years). The median time from GCA diagnosis to PCP diagnosis was 3 months (range 1-18 months). All patients were taking prednisone (the median dosage 50 mg/day [range 30-80]) when diagnosed as having PCP. No patients were receiving PCP prophylaxis. PCP was diagnosed by positive smear on bronchoalveolar lavage fluid in 6 patients (86%) and by positive sputum polymerase chain reaction in 1 patient. All the patients were hospitalized (median duration 17 days [range 12-39 days]). Four patients (57%) were admitted to the intensive care unit. Three patients (43%) required mechanical ventilation. Two patients (29%) died; both were on mechanical ventilation. Conclusion. Although PCP is rare among patients with GCA, this preventable infection is associated with significant morbidity and mortality.