mec-a positive methicillin-susceptible staphylococcus aureus as a public health concern: a case series

Background: staphylococcus aureus, an opportunistic microorganism, is the leading cause of severe bloodstream infections, including sepsis and endocarditis, which can be life-threatening. therefore, s. aureus infection poses a significant public health challenge, particularly in developing nations. mec-a is a genetic element commonly found in methicillin-resistant staphylococcus aureus (mrsa) strains that characterises the s. aureus resistance phenotype.methods: clinical infection samples obtained from blood were collected and categorised as mrsa or methicillin-sensitive staphylococcus aureus (mssa) using the vitek-2 compact device. subsequently, specific samples were gathered as case series owing to their unique characteristics. resistance genes were detected using conventional polymerase chain reaction (pcr), followed by visualisation through electrophoresis.results: our findings were based on the identification of five instances of mssa among samples obtained from a tertiary hospital’s microbiology laboratory. using the vitek-2 antimicrobial susceptibility profile, these cases were determined to be mssa. subsequently, we conducted pcr, which revealed the presence of a mec-a-positive strain. upon re-examination using mueller–hinton agar, the five strains were confirmed to be mssa. further analysis demonstrated that all strains were positive for panton-valentine leucocidin (pvl) and exfoliative toxin a (eta) gens.conclusions: the positive mec-a mssa results should serve as a warning to clinicians that a resistant strain is forthcoming. mec-a continues to be the benchmark for confirming the resistance phenotype. additional research is essential to explore this strain.