Multidrug-Resistant Coagulase-Negative Staphylococci Isolated from Bloodstream in the uMgungundlovu District of KwaZulu-Natal Province in South Africa: Emerging Pathogens

Abstract

Coagulase-negative staphylococci (CoNS) are increasingly associated with nosocomial infections, especially among the immunocompromised and those with invasive medical devices, posing a significant concern. We report on clinical multidrug-resistant CoNS from the uMgungundlovu District, KwaZulu-Natal Province, South Africa, as emerging pathogens. One hundred and thirty presumptive CoNS were obtained from blood cultures. Culture, biochemical tests, and the Staphaurex™ Latex Agglutination Test were used for the initial identification of CoNS isolates; confirmation and speciation were undertaken by the VITEK 2 system. Susceptibilities of isolates against a panel of 20 antibiotics were determined using the Kirby-Bauer disk diffusion method, and the multiple antibiotic resistance (MAR) indices of the isolates were determined. The polymerase chain reaction (PCR) was used to amplify the mecA gene to confirm methicillin resistance. Overall, 89/130 presumptive CoNS isolates were confirmed as CoNS by the VITEK 2 system. Of these, 68 (76.4%) isolates were putatively methicillin-resistant by the phenotypic cefoxitin screen test and 63 (92.6%) were mecA positive. Staphylococcus epidermidis (19.1%), S. hominis ssp hominis (15.7%), and S. haemolyticus (16.9%) were the most common CoNS species. Isolates showed high percentage resistance against penicillin (100.0%), erythromycin (74.2%), and azithromycin (74.2%) while displaying high susceptibilities to linezolid (95.5%), gentamicin (95.5%), and tigecycline (94.4%). Multidrug resistance (MDR) was observed in 76.4% of isolates. MAR index calculation revealed 71.9% of isolates with MAR index >0.2 and 20.2% >0.5. Isolates with the highest MAR indices (0.7 and 0.8) were recovered from the neonatal intensive care unit. Fifty-one MDR antibiograms were observed. The high prevalence of methicillin resistance and multidrug resistance in several species of CoNS necessitates surveillance of this emerging pathogen, currently considered a contaminant of microbial cultures.

Common Bacterial Isolates Associated With Neonatal Sepsis and Their Antimicrobial Profile: A Retrospective Study at King Abdulaziz University Hospital, Jeddah, Saudi Arabia

“…The increasing trend of antibiotic resistance of CoNS to various agents has been documented in multiple reports. This is significant, as not only can CoNS develop antibiotic resistance easily, but it can also transfer the developed resistance genes to other microorganisms [50][51][52].…”

Genomic Analysis of Antibiotic-Resistant Staphylococcus epidermidis Isolates From Clinical Sources in the Kwazulu-Natal Province, South Africa

“…Sixteen MRSE isolates, selected as a subsample from a previous study ( Asante et al, 2021 ) based on their resistance profiles, were subjected to whole-genome sequencing (WGS). Briefly, an initial 89 suspected CoNS isolates were collected from blood cultures sourced from hospitals within the uMgungundlovu District in the KwaZulu-Natal Province.…”

Exploring the Biofilm Formation Capacity in S. pseudintermedius and Coagulase-Negative Staphylococci Species

“…CoNS can colonize specific body parts and cause specific infections; for example, S. haemolyticus is involved in native valve endocarditis and S. saprophyticus is responsible for up to 10% of urinary tract infections in women [7]. In addition, numerous studies have reported an increase in antimicrobial resistance in CoNS, which limits the therapeutic options [8][9][10]. Regardless of the host, CoNS might be generally prone to increased antimicrobial resistance carriage since CoNS isolated from various animal species also carried resistance to several classes of antimicrobials [11][12][13][14].…”