Prevalence of methicillin-resistant coagulase-negative staphylococci and their antibiotic resistance profile in Zagazig University intensive care units
摘要
Coagulase-negative staphylococci (CoNS) are important opportunistic hospital pathogens. Their ability to acquire antibiotic resistance, especially to methicillin, poses a challenge in clinical management. This study was conducted to determine the prevalence, antibiotic resistance, and genetic profiles of methicillin-resistant (MR) CoNS isolates causing infections in intensive care unit (ICU) patients.
Methods and resultsA total of 785 hospital-acquired infection samples were investigated, and 113 CoNS strains were identified out of them. Methicillin-resistant isolates were tested for the mecA and mecC genes by using polymerase chain reaction (PCR), followed by DNA sequencing to investigate potential genetic variations. Among the 113 CoNS isolates, 50 (44.2%) were identified as methicillin-resistant. Among these, S. epidermidis exhibited the highest rate of methicillin resistance. Vancomycin and linezolid resistance were each detected in 18% of the isolates. Most of the isolates (45/50, 90%) were multidrug-resistant (MDR), with a multiple-antibiotic resistance (MAR) index ranging from 0.27 to 1. The mecA gene was detected in all of the MR-CoNS isolates, whereas no isolate tested positive for the mecC gene. Nucleotide sequencing of the mecA gene in the selected MR-CoNS revealed high sequence similarity among different species.
ConclusionsThe widespread presence of mecA and high rates of methicillin and multidrug resistance in CoNS emphasize the need for routine monitoring and infection control strategies in hospital settings.