BRONCHOALVEOLAR LAVAGE CELL COMPOSITION IN ALLOGENEIC BONE-MARROW TRANSPLANT PATIENTS WITHOUT SYMPTOMATIC LUNG COMPLICATIONS

The purpose of this study was to assess the cytological composition of bronchoalveolar lavage (BAL) fluid in allogeneic BMT patients without lung complications and compare it with that obtained from healthy vol unteers, During the first 6 months post-BMT we studied the differentia l cell counts of 98 BALs from 56 patients as well as the total cell co unt of 44 BALs from 27 patients, The BAL cellular composition in BMT p atients was clearly different from that of healthy subjects: there was a marked increase in alveolar neutrophils (in 82% of the patients whe n sequential BALs were performed) and an increase in lymphocytes, with a lower percentage of macrophages and similar numbers of eosinophils, A greater variation in cellular populations was found without an evid ent cause. The total number of cells per mi of fluid recovered appeare d similar to that of healthy volunteers, A high frequency of neutrophi lic alveolitis was found in patients with asymptomatic CMV on BAL, Owi ng to the variability of BAL cellular composition in asymptomatic BMT patients and its difference from that in healthy volunteers, great cau tion should be taken when interpreting the BAL composition data from p atients with lung complications. In order to avoid drawing wrong concl usions these data should be compared with those obtained from a contro l group of BMT patients without lung complications and not from health y volunteers.