Histopathologic features of Burkholderia cepacia pneumonia in patients without cystic fibrosis

Abstract

We present the histopathologic features of fatal Burkholderia cepacia pneumonia in three adults (one man [age 44 years] and two women [aged 40 and 43 years]). In all patients, the pulmonary infiltrates initially were localized (right middle lobe, left upper lobe, and right middle lobe) but rapidly progressed. Two open-lung biopsies and one pneumonectomy specimen showed necrotizing granulomatous inflammation merging with areas of more conventional necrotizing bronchopneumonia. In one patient, a mediastinal lymph node also showed stellate necrotizing granulomas. Vasculitis was absent. B. cepacia was cultured from the open-lung biopsies and bronchial wash specimens in two patients and from postmortem cultures of lung, subcarinal lymph nodes, and blood in the third. The histopathology in these patients resembles that of melioidosis, which is caused by a related organism, Burkholderia pseudomallei. B. cepacia needs to be considered in the differential diagnosis of necrotizing granulomatous inflammation. In addition, given the rarity with which B. cepacia is identified as a cause of pneumonia in the immunocompetent host, isolation of B. cepacia should trigger a workup for underlying immunodeficiency or lead to an investigation to exclude the possibility of a nosocomial infection.