Corynebacterium are gram-positive, catalase-positive, non-spore-forming, non-motile, rod-shaped bacteria that are straight or slightly curved.
They are widely distributed in nature in the microbiota of animals (including the human microbiota) and are mostly innocuous, most commonly existing in commensal relationships with their hosts. They occur most commonly in the soil, water, plants, and food products. The nondiphtheiroid Corynebacterium species can be found in the mucosa and normal skin flora of humans and animals.
The most notable human infection is diphtheria, caused by C. diphtheriae, which acquires the capacity to produce diphtheria toxin only after interacting with a bacteriophage. It is an acute and contagious infection characterized by pseudomembranes of dead epithelial cells, white blood cells, red blood cells, and fibrin that form around the tonsils and back of the throat.
Diptheria is uncommon in developed countries and tends to occur in unvaccinated individuals, especially school-aged children, elderly, neutropenic or immunocompromised patients, and those with prosthetic devices such as prosthetic heart valves, shunts, or catheters. It is more common in developing countries and can occasionally infect wounds, the vulva, the conjunctiva, and the middle ear.
Other pathogenic species in humans include, C. amycolatum, C. striatum, C. jeikeium, C. pseudotuberculosis, C. urealyticum, and C. xerosis, and these primarily cause infection in immunosuppressed patients.
Women’s Health: Have been Isolated from blood cultures for women with fever in labour/chorioamnionitis but rarely.
Colonization of the mucosa
Pseudomembranous tonsillitis associated with C. diptheriae
Infection in immunocompromised hosts
Hospital acquired infection
Caseous lymphadenitis associated with C. pseudotuberculosis
Skin infections (rare)