Impact of Burkholderia dolosa on lung function and survival in cystic fibrosis.
BACKGROUND
Chronic infection with Burkholderia cepacia complex bacteria in cystic fibrosis is associated with accelerated decline in pulmonary function and increased mortality. Clinical implications of the recently characterized genomovar VI, B. dolosa, are unknown.


OBJECTIVE
Characterization of impact of B. dolosa on pulmonary function and mortality in cystic fibrosis.


METHODS
We compared patients chronically infected with B. dolosa (n = 31) with unmatched patients with B. multivorans (n = 24) and with age- and sex-matched control subjects without Burkholderia species (n = 58). We analyzed rates of pulmonary function decline (% predicted FEV(1)) using a random effects model assuming segmented linear trends. All available FEV(1) measurements from 5 yr (median, 4.8) before until 2.5 yr (median, 1.5) after the first positive culture for Burkholderia (reference date) were analyzed. Survival was compared using the Kaplan-Meier method and proportional hazards model.


RESULTS
Baseline FEV(1) and rate of decline were similar in the cohorts. Decline in FEV(1) after the reference date accelerated in patients with B. dolosa (-2.3 percentage points/yr pre vs. -7.1 post, p = 0.002), but was unchanged in the B. multivorans and control patients (-2.3 vs. -0.8 post, p = 0.38, and -2.1 pre vs. -0.5 post, p = 0.20, respectively). The probability of dying within 18 mo of the reference date was 13, 7, and 3% for B. dolosa, B. multivorans, and control patients, respectively (B. dolosa vs. control hazard ratio, 10.8; 95% confidence interval, 1.3-92.8; p = 0.03).


CONCLUSIONS
B. dolosa chronic infection in cystic fibrosis is associated with accelerated loss of lung function and decreased survival.
Kalish
Leslie A
LA
Infectious Diseases Division, Clinical Research Program; Division of Respiratory Diseases, Infection Control Program, Department of Laboratory Medicine, Children's Hospital Boston, 300 Longwood Avenue, Boston, MA 02115, USA.
Waltz
David A
DA
Dovey
Mark
M
Potter-Bynoe
Gail
G
McAdam
Alexander J
AJ
Lipuma
John J
JJ
Gerard
Craig
C
Goldmann
Donald
D
D000328:Adult; D019121:Burkholderia Infections / Q000150:complications* / Q000503:physiopathology*; D015331:Cohort Studies; D003550:Cystic Fibrosis / Q000150:complications / Q000401:mortality* / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D012129:Respiratory Function Tests; D015996:Survival Rate