Bronchoalveolar lavage during neutropenic episodes: diagnostic yield and cellular pattern.

Few data are available concerning the relationship between alveolar and blood cell populations during neutropenia. We wanted to compare the value of pulmonary endoscopic procedures with lavage in neutropenic (polymorphonuclear (PMN) count < or = 1,000.mm-3) and non-neutropenic settings. We therefore, retrospectively, reviewed the results of 118 investigations for pneumonia in patients with malignant haematological diseases. All had bronchoalveolar lavage (BAL), and some had additional studies with protected bacteriological samples. Each BAL specimen was studied after cytocentrifugation by cytological examination for opportunistic infections, haemorrhage, virus, legionellae, and bacteriological cultures. The diagnostic yield of all endoscopic procedures (BAL, telescoping plugged catheter and protected specimen brush) was 53% in neutropenic (Group 1) and 61% in non-neutropenic (Group 2) patients. The aetiological pattern of pneumonia was nearly the same in the two groups, except for more alveolar proteinosis in Group 1 and more cytomegalovirus (CMV) in Group 2. The absolute number of alveolar cells recovered through BAL (total number, macrophages, lymphocytes and PMNs) was significantly lower in neutropenic patients. We conclude that: 1) neutropenic patients with pneumonia require the same investigative approach as non-neutropenic patients; 2) profound neutropenia may be concomitant with a decreased cellularity of alveoli, which may reflect the consequences of marrow aplasia on the pulmonary cell population and/or direct effect of chemotherapy on the lung.