Burkholderia cepacia complex

Burkholderia cepacia complex (BCC), or simply Burkholderia cepacia is a group of catalase-producing, non-lactose-fermenting Gram-negative bacteria composed of at least nine different species, including B. cepacia, B. multivorans, B. cenocepacia, B. vietnamiensis, B. stabilis, B. ambifaria, B. dolosa, B. anthina, and B. pyrrocinia.^[1] B. cepacia is an important human pathogen which most often causes pneumonia in immunocompromised individuals with underlying lung disease (such as cystic fibrosis or chronic granulomatous disease).^[2]

Additional recommended knowledge

Essential Laboratory Skills Guide

How to quickly check pipettes?

Weighing the right way

Pathogenesis

BCC organisms are typically found in water and soil and can survive for prolonged periods in moist environments. Person-to-person spread has been documented; as a result, many hospitals, clinics, and camps for patients with cystic fibrosis have enacted strict isolation precautions for those infected with BCC. Infected individuals are often treated in a separate area than noninfected patients to limit spread, since BCC infection can lead to a rapid decline in lung function and result in death.

Diagnosis of BCC involves isolation of bacteria from sputum cultures. BCC organisms are naturally resistant to many common antibiotics including aminoglycosides and polymyxin B.^[3] The bacteria is so hardy that it has been found to persist in betadine (a common topical antiseptic).^[4] Treatment typically includes multiple antibiotics and may include ceftazidime, doxycycline, piperacillin, chloramphenicol, and co-trimoxazole.^[3] In April 2007 Researchers from the Schulich School of Medicine & Dentistry at The University of Western Ontario, working with a group from Edinburgh, announced they had discovered a way to kill the the organism.^[5][6]

History

B.cepacia was discovered by Walter Burkholder in 1949 as the culprit of onion skin rot, and first described as a human pathogen in the 1950s.^[7] In the 1980s, it was first recognized in individuals with cystic fibrosis, and outbreaks were associated with a 35% death rate. Burkholderia cepacia has a large genome, containing twice the amount of genetic material as E. coli.

References