Reports of Biochemistry and Molecular Biology

en Mec-A Positive Methicillin-Susceptible Staphylococcus Aureus as a Public Health Concern: A Case Series میکروب شناسی Microbiology گزارش مورد Case Report <div style="text-align: justify;">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.</div> MSSA, mec-a, Staphylococcus aureus. 196 203 http://rbmb.net/browse.php?a_code=A-10-1515-1&slc_lang=en&sid=1 Sri Amelia sriamelia@usu.ac.id. 100319475328460020389 100319475328460020389 Yes Department of Microbiology, Faculty of Medicine, Universitas Sumatera Utara, Medan, Indonesia. Rozaimah Zein-Hamid 100319475328460020390 100319475328460020390 No Department of Clinical Pharmacology and Therapeutics, Faculty of Medicine, Universitas Sumatera Utara, Medan, Indonesia. Lia Kusumawati 100319475328460020391 100319475328460020391 No Department of Microbiology, Faculty of Medicine, Universitas Sumatera Utara, Medan, Indonesia & Clinical Microbiology Installation, Adam Malik General Hospital, Medan, Indonesia. Zulham Yamamoto 100319475328460020392 100319475328460020392 No Department of Histology, Faculty of Medicine, Universitas Sumatera Utara, Medan, Indonesia. Dewi Santosaningsih 100319475328460020393 100319475328460020393 No Department of Microbiology, Faculty of Medicine, Universitas Brawijaya, Malang, Indonesia. Putri Chairani Eyanoer 100319475328460020394 100319475328460020394 No Department of Community and Preventive Medicine, Faculty of Medicine, Universitas Sumatera Utara, Medan, Indonesia. Sunna Vyatra Hutagalung 100319475328460020395 100319475328460020395 No Department of Parasitology, Faculty of Medicine, Universitas Sumatera Utara, Medan, Indonesia. Masrul Lubis 100319475328460020396 100319475328460020396 No Division of Gastroenterohepatology, Department of Internal Medicine, Faculty of Medicine, Universitas Sumatera Utara, Medan, Indonesia. Alvin Ivander 100319475328460020397 100319475328460020397 No Faculty of Medicine, Universitas Sumatera Utara, Medan, Indonesia.