Survival of cystic fibrosis patients infected with Burkholderia cepacia complex genomovar III, Burkholderia multivorans...

Survival of cystic fibrosis patients infected with Burkholderia cepacia complex genomovar III, Burkholderia multivorans and Pseudomonas aeruginosa

A.M. Jones (Presenting)(1), M.E. Dodd (1), J.R.W. Govan (2), C.J. Doherty (2), V. Barcus (2), A.K. Webb (1)

(1)Manchester Adult Cystic Fibrosis Centre, South Manchester University Hospitals NHS Trust, Manchester, United Kingdom, Medical Microbiology, (2) University of Edinburgh, Edinburgh, United Kingdom

Introduction: Burkholderia cepacia comprises a number of distinct genomic species, known as genomovars. The majority of cystic fibrosis (CF) clinical isolates belong to genomovars II (B. multivorans) and III. The different severity of infection attributable to separate genomovars is unknown. We investigated whether survival differs between patients infected with B. multivorans, B. cepacia genomovar III and Pseudomonas aeruginosa.

Methods: Patients at the Manchester Adult CF Centre who developed chronic infection (1982-2001) with B. multivorans and genomovar III were included; each was matched with another CF patient with chronic P. aeruginosainfection using the percentage predicted FEV when the Burkholderia species was first isolated. The two Burkholderia species groups were each compared to their respective control groups for median survival time using the log rank test. Cepacia syndrome deaths and numbers progressing from initial to chronic infection were assessed for patients infected with Burkholderia species.

Results: Forty-eight patients had an initial infection with B. multivorans (n=15) or genomovar III (n= 33); 8/15 and 31/33, respectively, developed chronic infection (P<0.001). For the B. multivorans group and their matched controls there were 4/8 (1x ‘cepacia syndrome') and 3/8 deaths with a median survival of 112 and 114 months, respectively, (P=0.63). For the genomovar III group and their controls there were 21/31 (2x‘cepacia syndrome') and 12/31 deaths with a median survival time of 94 and 130 months, respectively, (P=0.05).

Conclusions: CF patients with B. cepacia genomovar III infection have a shortened survival in comparison with those with P. aeruginosa infection; however there is no difference in survival between patients infected with B. multivorans and P. aeruginosa.