Biochemical Test of Burkholderia cepacia


Burkholderia cepacia is a group of bacteria that can cause serious infections in humans, especially in people with cystic fibrosis or chronic lung diseases. It is also known as the B. cepacia complex (BCC) because it consists of more than 20 different species that share some genetic and phenotypic traits. B. cepacia can be found in various natural and man-made environments, such as soil, water, plants, animals, and medical devices. It can also colonize the respiratory tract of healthy individuals without causing any symptoms.

B. cepacia is a gram-negative, aerobic, rod-shaped bacterium that belongs to the order Burkholderiales. It has several features that make it resistant to many antibiotics and disinfectants, such as:

  • A thick and complex cell wall that prevents the penetration of some antimicrobial agents
  • The ability to produce biofilms that protect the bacteria from environmental stress and host immune response
  • The presence of efflux pumps that expel toxic substances from the cell
  • The expression of enzymes that degrade or modify antibiotics
  • The acquisition of plasmids or transposons that carry resistance genes

B. cepacia can also survive under harsh conditions, such as high temperature, low pH, high salinity, and low oxygen levels. It can use a variety of organic and inorganic compounds as sources of carbon and energy, such as sugars, alcohols, amino acids, fatty acids, and hydrogen sulfide. It can also perform different types of metabolism, such as aerobic respiration, anaerobic respiration, fermentation, and photosynthesis.

B. cepacia has a high genetic diversity and variability, which allows it to adapt to different environments and hosts. It can exchange genetic material with other bacteria through horizontal gene transfer mechanisms, such as transformation, conjugation, and transduction. It can also undergo genomic rearrangements or deletions that affect its phenotype and virulence.

B. cepacia is a versatile and opportunistic pathogen that can cause a range of infections in humans, such as:

  • Respiratory infections: B. cepacia can cause pneumonia, bronchitis, bronchiectasis, or lung abscesses in people with compromised respiratory systems. It can also cause a severe and fatal syndrome called cepacia syndrome, which is characterized by rapid deterioration of lung function and septic shock.
  • Bloodstream infections: B. cepacia can enter the bloodstream through wounds, catheters, or intravenous lines and cause bacteremia or sepsis.
  • Skin and soft tissue infections: B. cepacia can infect the skin or underlying tissues through cuts, burns, ulcers, or surgical sites and cause cellulitis, abscesses, or necrotizing fasciitis.
  • Urinary tract infections: B. cepacia can infect the urinary tract through catheters or urinary devices and cause cystitis, pyelonephritis, or urosepsis.
  • Other infections: B. cepacia can also infect other organs or systems in the body, such as the eyes (conjunctivitis), ears (otitis media), sinuses (sinusitis), bones (osteomyelitis), joints (arthritis), heart (endocarditis), brain (meningitis), or abdomen (peritonitis).

B. cepacia is a challenging bacterium to diagnose and treat because of its variable clinical presentation, its resistance to many antibiotics, and its ability to persist in the host. Therefore, it is important to identify it accurately and promptly using biochemical tests and molecular methods. In this article, we will discuss some of the biochemical tests that can be used to detect the fermentation and enzymatic reactions of B. cepacia.