Prevalence of mecA- and mecC-Associated Methicillin-Resistant Staphylococcus aureus in Clinical Specimens, Punjab, Pakistan

Abstract

Methicillin-resistant Staphylococcus aureus (MRSA) is a clinically prevalent bacterium and is resistant to many drugs. Genetic factors such as mec genes are considered to be responsible for this resistance. Recently, Staphylococcal Cassette Chromosome mec (SCCmec) element mutations produced mecC, a new genetic variant that encodes a transpeptidase enzyme (63% similarity with mecA-encoded PBP2a). This cross-sectional study was conducted to establish the prevalence of the mecA and mecC genes among phenotypically identified MRSA and their effectiveness against different antibiotics in clinical specimens. The prevalence of Staphylococcus aureus was 10.2% (n = 102) in the total number of clinical specimens collected (n = 1000). However, the prevalence of MRSA was 6.3% (n = 63) of the total samples collected, while it was 61.8% among total Staphylococcus aureus isolates. mec genes were confirmed in 96.8% (n = 61) isolates of MRSA, while 3.2% (n = 2) were found to be negative for mec genes. The combination of mecA and mecC was detected in 57.1% (n = 36) of the MRSA isolates. The prevalence of lone mecA was 31.8% (n = 20) and that of lone mecC was 7.9% (n = 5) among all the MRSA samples. Penicillin and amoxicillin/clavulanic acid were the most resistant antibiotics followed by norfloxacin (91.2%), levofloxacin (87.1%), ciprofloxacin (83.9%), azithromycin (78.6%), erythromycin (77.4%), moxifloxacin (69.8%), and sulfamethoxazole/trimethoprim (54.9%). On the other hand, vancomycin and teicoplanin (98.4%) were more effective drugs against MRSA followed by linezolid (96.7%), clindamycin (84.6%), chloramphenicol (83.7%), fusidic acid (70.6%), gentamicin (67.7%), and tetracycline (56.8%). In conclusion, a significant prevalence of mecA and mecC has been found among MRSA isolated from clinical specimens, which is likely responsible for antibiotic resistance in MRSA in our clinical settings. However, vancomycin, teicoplanin, and linezolid were found the top three most effective drugs against MRSA in our clinical settings. Thus, MRSA endemics in local areas require routine molecular and epidemiological investigation.

Potential Surviving Effect of Cleome droserifolia Extract against Systemic Staphylococcus aureus Infection: Investigation of the Chemical Content of the Plant

“…Here, the tested S. aureus isolates were from blood (52.17%), wounds (21.73%), sputum (17.4%), and urine (8.7%). Previous studies have documented that most recovered S. aureus isolates were from blood and wounds [86][87][88]. Regarding the susceptibility to antibiotics, the isolates tested in our study revealed multidrug resistance comparable to previous reports [89][90][91].…”

Kinship analysis of mecA gene of methicillin-resistant Staphylococcus aureus isolated from milk and risk factors from the farmers in Blitar, Indonesia

“…In 2007, the mecA gene was first isolated from an MRSA isolate originating from milk of dairy cows in England [51]. The mecA gene of MRSA bacteria is a determining factor in the occurrence of antibiotic resistance [52]. This type of antibiotic resistance occurs in the β-lactam antibiotic class, where resistance occurs due to the presence of PBP2a protein [53].…”

Methicillin-resistant coagulase-positive staphylococci in new, middle-aged, and old veterinary hospitals in southern Thailand: A preliminary study

“…Staphylococcal infections have been frequently observed in humans, dogs, cats, horses, sheep, pigs, cattle, and chickens [ 7 – 12 ]. Methicillin-resistant CoPS (MRCoPS) are opportunistic pathogens that have at least one drug resistance gene on their chromosome, such as mecA or mecC , which compromises or abolishes the efficacy of beta-lactam agents in antimicrobial therapy [ 4 , 13 – 15 ].…”