Coagulase-Negative Staphylococci

Abstract

SUMMARY The definition of the heterogeneous group of coagulase-negative staphylococci (CoNS) is still based on diagnostic procedures that fulfill the clinical need to differentiate between Staphylococcus aureus and those staphylococci classified historically as being less or nonpathogenic. Due to patient- and procedure-related changes, CoNS now represent one of the major nosocomial pathogens, with S. epidermidis and S. haemolyticus being the most significant species. They account substantially for foreign body-related infections and infections in preterm newborns. While S. saprophyticus has been associated with acute urethritis, S. lugdunensis has a unique status, in some aspects resembling S. aureus in causing infectious endocarditis. In addition to CoNS found as food-associated saprophytes, many other CoNS species colonize the skin and mucous membranes of humans and animals and are less frequently involved in clinically manifested infections. This blurred gradation in terms of pathogenicity is reflected by species- and strain-specific virulence factors and the development of different host-defending strategies. Clearly, CoNS possess fewer virulence properties than S. aureus , with a respectively different disease spectrum. In this regard, host susceptibility is much more important. Therapeutically, CoNS are challenging due to the large proportion of methicillin-resistant strains and increasing numbers of isolates with less susceptibility to glycopeptides.

Antibiotic surgical prophylaxis increases nasal carriage of antibiotic-resistant staphylococci

“…Also with the acquisition of S. haemolyticus and S. hominis there is potential for opportunistic infection such as endocarditis, with multi-antibiotic-resistant strains being more difficult to treat (Becker et al, 2014).…”

Treatment of native valve endocarditis due to coagulase negative staphylococci, complicated by a drug reaction with eosinophilia and systemic symptoms (DRESS syndrome)

“…Of 1635 patients with definite native valve endocarditis and no history of injection drug use, 128 (7.8%) had native valve endocarditis due to CoNS of which S. epidermidis was the predominant isolate (80% of 93 speciated CoNS isolates from NVE patients). 3 In a global endocarditis study, S. lugdunensis was reported as the second most common CoNS. 4 However, it is quite unusual for this organism to cause endocarditis in an otherwise healthy person who is not an intravenous drug user.…”

“…CoNS is proven to have small colony variants (a specific phenotype resulting from a switch from normal phenotype) similar to S. aureus and hence, it can give appearance of a mixed growth. 3 The recommendation of the Infectious Diseases Society of America (IDSA 2015) in the management of staphylococcal endocarditis is vancomycin or daptomycin for 6 weeks. 5 These guidelines recommend that vancomycin trough levels be maintained between 10 -20 µg/ml.…”

“…His presentation with embolic phenomena manifesting with neurological symptoms is unusual as patients with NVE due to CoNS are less likely to have embolic events, compared with patients with NVE due to S. aureus. 3 Dukes criteria were fulfilled with one major and 3 minor criteria 5 . However, he did not have a prosthesis which CoNS are commonly associated with.…”

Antimicrobial susceptibility profile and research of mec A and erm genes in coagulase-negative staphylococci isolated from platelet concentrates bags

“…Currently, CoNS represent one of the major nosocomial pathogens and S. epidermidis and S. haemolyticus are the most significant species. Moreover, the increasing rates of antibiotic resistance are an even greater problem for CoNS than for Staphylococcus aureus, limiting our therapeutic options (Becker, Heilmann, Peters, 2014).…”