| Burkholderia cepacia complex | |
|---|---|
| Scientific classification | |
| Kingdom: | Bacteria |
| Phylum: | Proteobacteria |
| Class: | Beta Proteobacteria |
| Order: | Burkholderiales |
| Family: | Burkholderiaceae |
| Genus: | Burkholderia |
| Species: | B. cepacia complex |
| Binomial name | |
| Burkholderia cepacia complex (Palleroni and Holmes 1981) Yabuuchi et al. 1993 |
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| Type species | |
| ATCC 25416 CCUG 12691 and 13226 |
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| Synonyms | |
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Pseudomonas cepacia Burkholder 1950 |
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Burkholderia cepacia complex (BCC), or simply Burkholderia cepacia is a group of catalase-producing, non-lactose-fermenting Gram-negative bacteria composed of at least seventeen 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]
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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 have enacted strict isolation precautions for those infected with BCC. Infected individuals are often treated in a separate area from 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 culturing the bacteria from clinical specimens such as sputum or blood. BCC organisms are naturally resistant to many common antibiotics including aminoglycosides and polymyxin B.[3] and this fact is exploited in the identification of the organism.
Oxidation-fermentation polymyxin-bacitracin-lactose (OFPBL) agar contains polymyxin (which kills most gram-negative bacteria, including Pseudomonas aeruginosa) and bacitracin (which kills most gram-positive bacteria and Neisseria species).[4][5] It also contains lactose, and organisms such as BCC that ferment lactose turn the pH indicator yellow, which helps to distinguish it from other organisms that may grow on OFPBL agar, such as Candida species, Pseudomonas fluorescens, Stenotrophomonas species, and Proteus species.
The bacteria is so hardy that it has been found to persist in betadine (a common topical antiseptic).[6] Recently, a 0.2% chlorhexidine mouthwash was also recalled, after it was found to be contaminated with B. cepacia.[7]
Treatment typically includes multiple antibiotics and may include ceftazidime, doxycycline, piperacillin, meropenem, chloramphenicol and co-trimoxazole(trimethoprim/sulfamethoxazole).[3] Although co-trimoxazole has been generally considered the drug of choice for Burkholderia cepacia infections ceftazidime, doxycycline, piperacillin and meropenem are considered to be viable alternative options in cases where co-trimoxazole cannot be administered because of hypersensitivity reactions, intolerance or resistance.[8] 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 organism.[9][10]
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.[11] 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.
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