Update on Coagulase-Negative Staphylococci—What the Clinician Should Know

Abstract

Coagulase-negative staphylococci (CoNS) are among the most frequently recovered bacteria in routine clinical care. Their incidence has steadily increased over the past decades in parallel to the advancement in medicine, especially in regard to the utilization of foreign body devices. Many new species have been described within the past years, while clinical information to most of those species is still sparse. In addition, interspecies differences that render some species more virulent than others have to be taken into account. The distinct populations in which CoNS infections play a prominent role are preterm neonates, patients with implanted medical devices, immunodeficient patients, and those with other relevant comorbidities. Due to the property of CoNS to colonize the human skin, contamination of blood cultures or other samples occurs frequently. Hence, the main diagnostic hurdle is to correctly identify the cases in which CoNS are causative agents rather than contaminants. However, neither phenotypic nor genetic tools have been able to provide a satisfying solution to this problem. Another dilemma of CoNS in clinical practice pertains to their extensive antimicrobial resistance profile, especially in healthcare settings. Therefore, true infections caused by CoNS most often necessitate the use of second-line antimicrobial drugs.

Coagulase-Negative Staphylococci Clones Are Widely Distributed in the Hospital and Community

“…The pathogenic potential of CoNS is mainly related to some virulence factors, especially biofilm, but also toxins and antimicrobial resistance. Some criteria are used to determine if a CoNS is a true cause of infection, such as absence of infection caused by another microorganism, presence of two or more isolates of the same species, improvement of symptoms after therapy, presence of foreign body, time for positivity less than 16 hours, and antibiotic resistance [ 6 , 7 ]. It is a known fact that CoNS infections may be seriously impacted by antimicrobial resistance.…”

Evaluation of Biofilm Formation and Prevalence of Multidrug-Resistant Strains of Staphylococcus epidermidis Isolated from Neonates with Sepsis in Southern Poland

“…It has been noted that the strains causing infections are more likely to carry genetic determinants of resistance, pathogenicity, and biofilm, but the results obtained so far suggest that there is no single distinction marker which can be used in routine diagnostics. Therefore, the studies concerning the analysis of Staphylococcus epidermidis virulence, resistance, and biofilm formation contribute to enhancing the knowledge concerning this important bacterium [ 18 , 19 ].…”

Distribution and antibiotic-resistance of different Staphylococcus species identified by matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) isolated from the oral cavity

“…As a result, they can be involved in a variety of infections with various locations, manifestations and outcomes. CoNS can cause severe infections, such as septicaemia, native and prosthetic valve endocarditis, shunt-associated meningitis, osteomyelitis, and urinary tract infections [ 3 , 4 ]. The infections mentioned above occur primarily in immunocompromised patients and persons with indwelling medical devices [ 5 ].…”