Implications of identifying the recently defined members of the Staphylococcus aureus complex S. argenteus and S. schweitzeri: a position paper of members of the ESCMID Study Group for Staphylococci and Staphylococcal Diseases (ESGS)

Abstract

Background: Staphylococcus argenteus and Staphylococcus schweitzeri, previously known as divergent Staphylococcus aureus clonal lineages, have been recently established as novel, difficult-to-delimit, coagulase-positive species within the S. aureus complex. Methicillin-resistant strains of S. argenteus are known from Australia and the UK. Knowledge of their epidemiology, medical significance and transmission risk is limited and partly contradictory, hampering definitive recommendations. There is mounting evidence that the pathogenicity of S. argenteus is similar to that of 'classical' S. aureus, while as yet no S. schweitzeri infections have been reported. Aim: To provide decision support on whether and how to distinguish and report both species. Sources: PubMed, searched for S. argenteus and S. schweitzeri. Content: This position paper reviews the main characteristics of both species and draws conclusions for microbiological diagnostics and surveillance as well as infection prevention and control measures. Implications: We propose not distinguishing within the S. aureus complex for routine reporting purposes until there is evidence that pathogenicity or clinical outcome differ markedly between the different species. Primarily for research purposes, suitably equipped laboratories are encouraged to differentiate between S. argenteus and S. schweitzeri. Caution is urged if these novel species are explicitly reported. In such cases, a specific comment should be added (i.e. 'member of the S.aureus complex') to prevent confusion with less-or non-pathogenic staphylococci. Prioritizing aspects of patient safety, methicillinresistant isolates should be handled as recommended for methicillin-resistant Staphylococcus aureus (MRSA). In these cases, the clinician responsible should be directly contacted and informed by the diagnosing microbiological laboratory, as they would be for MRSA. Research is warranted to clarify the epidemiology, clinical impact and implications for infection control of such isolates.

Antimicrobial resistant and enteropathogenic bacteria in ‘filth flies’: a cross-sectional study from Nigeria

“…Since S. schweitzeri is frequent in African wildlife, we tested if some isolates were misidentified by MALDI-TOF as S. aureus. All isolates were nuc positive and harboured the 160 bp-fragment of NRPS, thus ruling out S. schweitzeri in our collection 9 . The most predominant spa type was t674 (98%, 270/275) followed by singular occurrences of t1980, t5305 and t6313 (0.4%, 1/275 each, two isolates were not spa typeable).…”

First investigation of Staphylococcus argenteus in a Brazilian collections of S. aureus isolated from bovine mastitis

“…S. argenteus has been found in other regions of the world in human and animal isolates [3,9,21]. However, to date, this microorganism has not been reported in Brazil.…”

Molecular characterization of clinical isolates from vascular access infection: A single‐institution study

“…By contrast, CoNS and P. aeruginosa infections decreased by nearly 3%-5%. Previous studies have not addressed the spread or transmission of S. argenteus in the hospital environment (Becker et al, 2019). Nevertheless, the growing trend of S. argenteus in…”