Burkholderia cepacia in cystic fibrosis - Variable disease course

Variable clinical course has been reported with the acquisition of Burkhold eria cepacio in patients who have cystic fibrosis (CF). We hypothesized tha t the perceived worsening with B. cepocia may reflect the underlying severi ty of pulmonary disease at the time of acquisition. To test this hypothesis , we matched CF patients colonized with B. cepacia with CF patients not col onized with the organism. Two-year pre- and postacquisition data and long-t erm data were compared. Patients were matched for gender, age (+/- 1 yr), h eight (+/- 5 cm), weight (+/- 8 kg), percent predicted forced expiratory vo lume in one second (% pred FEV1) (+/- 10%), and pancreatic sufficiency stat us. Differences in rates of change pre- and postacquisition for FEV1, FVC,w eight, and frequency of intravenous courses were compared within pairs with the Wilcoxon signed rank test. Two-year and long-term survival was compare d within pairs with the McNemar test. No significant differences were obser ved in mean annual rates of change in weight (0.33 and -0.28 kg/yr), % pred FEV1 (-0.36 and -1.74%/yr), and percent predicted forced vital capacity (% pred FVC) (-3.80 and -2.32%/yr) between B. cepacio and control pairs in 2- yr and long-term postacquisition interval, respectively. Similar rates of c hange were noted for pre- to postacquisition intervals within pairs for wei ght (0.17 kg/yr), % pred FEV1 (-0.16%/yr), % pred FVC (5.02 %/yr). There wa s a significantly higher rate of intravenous antibiotic courses in B. cepoc ia cases in the 2-yr and long-term postacquisition interval. Higher mortali ty was observed in the B. cepacia cases in the long term (p < 0.05). We con clude that colonization with B. cepacia does not necessarily adversely affe ct pulmonary status, but is associated with reduced long term survival. Whe reas previous associations may be attributed to a propensity to colonize th ose who had more advanced disease, specific strain types of B. cepacio may have enhanced pathogenicity.