Burkholderia cepacia complex: impact on the cystic fibrosis lung lesion

Burkholderia cepacia complex (Bcc) is a group of phenotypically similar nonfermenting, aerobic, gram-negative rods that infect 2 to 8% of patients with cystic fibrosis (CF). Bcc comprises several distinct species (formerly termed genomovars). Infection with Bcc has been associated with worse outcomes and survival in CF patients. Additionally, colonization with Bcc has been associated with heightened mortality following lung transplantation. Currently, the role of lung transplantation in Bcc-infected patients remains controversial. Antimicrobial therapy for Bcc is often ineffective because most strains are multidrug resistant. Combination therapy with two or three agents is typically administered, but optimal therapy has not been elucidated. Certain strains (particularly B. cenocepacia) have been associated with heightened transmissibility and virulence. Several genes or gene products have important roles in virulence, persistence of the organism(s), and transmissibility. The incidence of Bcc and specific species fluctuates over time and between centers. Bcc can be transmitted by social contact, and several major epidemic strains have disseminated globally. Strict infection control measures, including cohorting (segregation) of infected patients, dramatically curtail transmission and have become the standard of care, but such measures cause social isolation, stigmatism, and psychological impact among infected patients.