90 Phenotypic and genotypic characteristics of the epidemic clones of Burkholderia cenocepacia strains in patients with cystic fibrosis (CF) in Russian Federation

Abstract

Background Lung infections caused by Burkholderia cepacia complex (Bcc) are the main reasons of the development of “cepacia syndrome” that is characterized by a necrotizing pneumonia. Aim To study phenotypic and genotypic characteristics of epidemic clones Bcc from CF patients in Russia. Methods 129 Bcc strains were studied by diagnostic algorithm included phenotypic and molecular techniques. Results The Russian Bcc strains belonged to B. cenocepacia – 166 strains, B. multivorans – 2, B. contaminans – 2, B. vietnamensis – 1. The strains of B. cenocepacia belonged to ST 709, 208, 241, 710, 708, 714, 727, 728. Dominant ST 709 was identified in 67.6% of patients, ST 208 in 12.4%. The contamination by strains ST 709 and ST 208 is supposed to occur during hospitalizations in Moscow and Samara. The strains ST 709 and ST 208 had lipase and proteolytical activity. 100% of strains were resistant to amikacin, gentamycin, tobramicin and imipenem, 14% to meropenem, 17.9% to ceftazidime. All Bcc strains were multiresistant. 83% of the strains had the ability to grow as a biofilm. PCR-based molecular analysis revealed the presence of BCESM marker in all strains. Microbiological monitoring revealed that the strains isolated at the beginning were identical to the strains isolated after 5 years. The change of the Bcc strains during the chronic infection or their elimination was not observed. Conclusion The predominant epidemical clones were Moscow ST 709 and Samara ST 208. They are multiresistant, have ability to persist in CF patient lungs and cause cross-infections. For improvement in the quality of life and long time survival of CF patients the monitoring of Bcc infection is absolutely necessary.