Cutibacterium acnes is the relatively slow-growing, typically aerotolerant anaerobic, Gram-positive bacterium linked to the skin condition of acne.
It is associated with chronic blepharitis and endophthalmitis.
Previously known as Propionibacteriaceae.
The species is largely commensal and part of the skin flora present on most healthy adults skin.
It is minimally detectable on the skin of healthy preadolescents, as it lives primarily on fatty acids in sebum secreted by sebaceous glands in the follicles.
Cutibacterium acnes may be found throughout the gastrointestinal tract.
It has the ability to generate propionic acid.
C. acnes bacteria predominantly live deep within follicles and pores of the skin.
It is also found on the surface of healthy skin.
C. acnes bacteria use sebum, cellular debris and metabolic byproducts from the surrounding skin tissue as their primary sources of energy and nutrients.
The elevated production of sebum by hyperactive sebaceous glands or blockage of the follicle can cause C. acnes bacteria to grow and multiply.
C. acnes bacteria secrete many proteins, and several digestive enzymes.
These digestive enzymes are involved in the digestion of sebum, and destabilize the layers of cells that form the walls of the follicle.
The growth of C. acnes creates cellular damage, metabolic byproducts and bacterial debris that can trigger inflammation.
The inflammation created can lead to common skin disorders of folliculitis and acne vulgaris.
Acne vulgaris is the disease most commonly associated with C. acnes infection.
C. acnes causes damage and inflammation in the associated affected tissue making it more susceptible to colonization by opportunistic bacteria, such as Staphylococcus aureus.
C. acnes has also been found in corneal ulcers.
C. acnes is a common cause of chronic endophthalmitis following cataract surgery.
It has been found in herniated discs, where it secretes propionic acid creating micro-fractures of the surrounding bone.
These micro-fractures induced by C. acnes respond to antibiotics and are helpful in resolving this type of low back pain.
C. acnes can be found in bronchoalveolar lavage of approximately 70% of patients with sarcoidosis and is associated with disease activity (It can be also found in 23% of controls).
C. acnes that cause infections on otherwise sterile tissues, and are likely local contaminants.
The severity of acne vulgaris is associated with virulent strains.
C. acnes is often an opportunistic pathogen: postoperative and device-related infections, post-neurosurgical infections, infected joint prostheses, neurosurgical shunt infections and endocarditis in patients with prosthetic heart valves.
C. acnes may play a role in other conditions: synovitis, acne, pustulosis, hyperostosis, osteitis syndrome, sarcoidosis and sciatica.
C. acnes is also suspected to be a main bacterial source of neuroinflammation in Alzheimer’s disease brains.
C. acnes is a common contaminant in blood and cerebrospinal fluid cultures.
Antimicrobial susceptibility of C. acnes bacteria involves a wide range of antimicrobial molecules.
The antibiotics most frequently used to treat acne vulgaris are erythromycin, clindamycin, doxycycline, and minocycline.
Other families of antibiotics active against C. acnes bacteria include: quinolones, cephalosporins, pleuromutilins, penicillins, and sulfonamides.
Antibiotic-resistance to C. acnes bacteria is a growing problem worldwide.
The antibiotic families that C. acnes are most likely to acquire resistance to are the macrolides, erythromycin and azithromycin, lincosamides, clindamycin, and tetracyclines, doxycycline and minocycline).
C. acnes bacteria are susceptible to many types of antimicrobial chemicals found in over-the-counter antibacterial products: benzoyl peroxide, and chlorhexidine gluconate.
Maturally occurring molecules and compounds are toxic to C. acnes bacteria: rosemary oil, tea tree oil, clove oil, and citrus oils contain antibacterial chemicals.
Natural honey has also been shown to have some antibacterial properties that may be active against C. acnes.
Silver, sulfur, and copper elements have are toxic towards many bacteria, including C. acnes.
C. acnes is killed by ultraviolet light, especially sensitive to light in the 405–420 nanometer, near the ultraviolet range, due to an endogenic porphyrin–coporphyrin III.