Variation of the antimicrobial susceptibility profiles of Burkholderia cepacia complex clonal isolates obtained from chronically infected cystic fibrosis patients: a five-year survey in the major Portuguese treatment center
- 376 Downloads
The treatment of cystic fibrosis (CF) patients chronically infected with Burkholderia cepacia complex (Bcc) bacteria requires extensive and aggressive antibiotics therapy, exposing these bacteria to prolonged antibiotics-selective pressure. In the present study, we have compared the susceptibility patterns to 13 antimicrobials of 94 Bcc isolates obtained from 15 Portuguese CF patients in the course of chronic infection during a five-year survey. These isolates were previously genotyped and represent 11 different strains of the species B. cenocepacia (subgroups A and B), B. cepacia, B. multivorans, and B. stabilis. The results are consistent with the notion that CF Bcc isolates are resistant to the most clinically relevant antimicrobials and suggest an uneven distribution of resistance rates among the different species, with B. cenocepacia subgroup A isolates being the most resistant. Phenotypic variants exhibiting differences in the antimicrobial susceptibility patterns were obtained from the sputum samples of clinically deteriorated CF patients during chronic lung infection. The isolation of resistant variants coincided with periods of pulmonary exacerbation and antibiotics therapy.
KeywordsCystic Fibrosis Minimal Inhibitory Concentration Ceftazidime Cystic Fibrosis Patient Antimicrobial Susceptibility Pattern
Burkholderia cepacia complex
This work was partially supported by FEDER and Fundação para a Ciência e Tecnologia (FCT), Portugal (contracts POCTI/BIO/38273/2001 and PTDC/SAU-MII/69591/2006 and PhD and post-doctoral grants to S.A.S and M.V.C., respectively).
- 6.Cunha MV, Pinto-de-Oliveira A, Meirinhos-Soares L, Melo-Cristino J, Salgado MJ, Correia S, Barreto C, Sá-Correia I (2007) Exceptionally high representation of Burkholderia cepacia among B. cepacia complex isolates recovered from the major Portuguese cystic fibrosis center. J Clin Microbiol 45:1628–1633PubMedCrossRefGoogle Scholar
- 9.Campana S, Taccetti G, Ravenni N, Favari F, Cariani L, Sciacca A, Savoia D, Collura A, Fiscarelli E, De Intinis G, Busetti M, Cipolloni A, d’Aprile A, Provenzano E, Collebrusco I, Frontini P, Stassi G, Trancassini M, Tovagliari D, Lavitola A, Doherty CJ, Coenye T, Govan JRW, Vandamme P (2005) Transmission of Burkholderia cepacia complex: evidence for new epidemic clones infecting cystic fibrosis patients in Italy. J Clin Microbiol 43:5136–5142PubMedCrossRefGoogle Scholar
- 16.Bevivino A, Dalmastri C, Tabacchioni S, Chiarini L, Belli ML, Piana S, Materazzo A, Vandamme P, Manno G (2002) Burkholderia cepacia complex bacteria from clinical and environmental sources in Italy: genomovar status and distribution of traits related to virulence and transmissibility. J Clin Microbiol 40:846–851PubMedCrossRefGoogle Scholar
- 18.Clinical Laboratory Standards Institute (CLSI) (2005) Performance standards for antimicrobial susceptibility testing; fifteenth informational supplement. National Committee for Clinical Laboratory Standards (NCCLS), M100-S15 (vol. 25, no.1)Google Scholar
- 20.Pitt TL, Kaufmann ME, Patel PS, Benge LCA, Gaskin S, Livermore DM (1996) Type characterisation and antibiotic susceptibility of Burkholderia (Pseudomonas) cepacia isolates from patients with cystic fibrosis in the United Kingdom and the Republic of Ireland. J Med Microbiol 44:203–210PubMedCrossRefGoogle Scholar
- 27.Cunha MV, Sousa SA, Leitão JH, Moreira LM, Videira PA, Sá-Correia I (2004) Studies on the involvement of the exopolysaccharide produced by cystic fibrosis-associated isolates of the Burkholderia cepacia complex in biofilm formation and in persistence of respiratory infections. J Clin Microbiol 42:3052–3058PubMedCrossRefGoogle Scholar