The role of opportunistic Corynebacterium spp. in human infections

Introduction. The non-diphtherial corynebacteria (diphtheroids, “coryneform” bacteria) have been increasingly recognized as causative agents of human infections. Aim. To provide an overview of the role of non-diphtherial Corynebacterium species in human infections. Material and methods. Analysis of the literature data found in the PubMed database. Results. The role of diphtheroids - inherently low-virulent microorganisms considered members of the human microbiota – as potential pathogens has been linked to specific risk factors including immunosuppression, implantation of biomaterials and invasive medical procedures. Their pathogenic potential is primarily associated with frequent multidrug resistance, the ability to adhere to biotic and abiotic surfaces and/or to form biofilm as well as with internalization, intracellular survival and persistence within human cells. The most common infections include bacteremia, sepsis, endocarditis, meningitis, urinary tract infections, respiratory tract infections, wound and skin infections, and endophthalmitis. The leading species are C. jeikeium, C. striatum, C. urealyticum, C. amycolatum, and C. pseudodiphtheriticum. Conclusion. Opportunistic corynebacteria can be responsible for a wide range of infections which can be expected to increase in frequency in the future due to an enlarging population of patients with predisposing risk factors but also due to the increasing problem of antibiotic resistance in this group of bacteria.