PREVALENCE AND ANTIBIOGRAM PROFILES OF STAPHYLOCOCCUS AUREUS ISOLATES FROM PATIENTS AT TAKSIN HOSPITAL, BANGKOK, THAILAND (JANUARY 2019 - MAY 2020)
Piyawan Pipobwatthana1 , Chalermsri Pummangura2 , Sasitorn Jaroennon1 , Chanwit Tribuddharat3 , Huttaya Thuncharoon1 , Apichot So-Ngern2 , Vipavee Rodjun2 , Ruxjinda Wattanalai2 and Somporn Srifuengfung2
Keywords:Staphylococcus aureus, antibiogram profile, drug resistance, methicillin resistance, clinical isolate, Thailand
Staphylococcus aureus is one of the most important bacteria that cause disease in humans. A total of 700 clinical S. aureus positive sputum (52.0%), pus (28.5%) and blood (14.8%) samples collected from patients who visited and/or were admitted to a tertiary care hospital, Bangkok, Thailand during January 2019 - May 2020 for the treatment of their illnesses were studied for their antibiogram profile. It was found that they were mostly methicillin-susceptible (MSSA) (77.1%) and those resistant to methicillin (MRSA) demonstrated sensitivity (70-100%) to fosfomycin, fusidic acid, gentamycin, tetracycline, trimethoprimsulfamethoxazole, and vancomycin [minimum inhibitory concentration (MIC) range, MIC50 and MIC90 = 0.25-2.0, 0.5 and 1.0 µg/ml using E-test] and resistance to ciprofloxacin, clindamycin, and erythromycin. MSSA isolates were sensitive (88-100%) to all test drugs except tetracycline. MSSA (7%) and MRSA (90%) isolates exhibited multiple drug resistance (MDR) phenotype, among the former group the most common MDR pattern was against clindamycin + erythromycin + tetracycline (4%), followed by clindamycin + erythromycin + fosfomycin (1%) and clindamycin + erythromycin + gentamycin + tetracycline (1%) while among the latter the most common MDR pattern was against ciprofloxacin + clindamycin + erythromycin (55%), followed by ciprofloxacin + clindamycin + erythromycin + fosfomycin (18%). Inducible lincosamides, macrolides and streptogramin B resistance (iMLSB) phenotypes were present in 3 and 10% of MSSA and MRSA isolates respectively, while constitutive MLSB (cMLSB) resistance phenotype in 8 and 79% respectively. In conclusion, the findings demonstrate a high percent MRSA isolates concomitant with MDR phenotypes among clinical S. aureus from various samples at a hospital in Bangkok.