Deepshikha Bhowmik1, Shiela Chetri2, Deepjyoti Paul3, Debadatta Dhar Chanda4, Amitabha Bhattacharjee5. 1. Junior Research Fellow (Microbiology), Assam University, Silchar, Assam, India. 2. Senior Research Fellow (Microbiology), Assam University, Silchar, Assam, India. 3. Research Associate (Microbiology), Assam University, Silchar, Assam, India. 4. Associate Professor (Microbiology), Silchar Medical College and Hospital, Silchar, Assam, India. 5. Assistant Professor (Microbiology), Assam University, Silchar, Assam, India.
Abstract
BACKGROUND: In Staphylococcus aureus, methicillin resistance is exhibited by modifications in penicillin-binding protein that minimises the binding affinity to beta-lactam antibiotics. The present study investigated the occurrence of methicillin-resistant S. aureus (MRSA) in community-acquired infections, that is, community-acquired MRSA (CA-MRSA) and in-hospital-acquired infections, that is, hospital-acquired MRSA (HA-MRSA) from Northeast India. METHODS: A total of 197 consecutive non-duplicate isolates were collected from Silchar Medical College and Hospital and other private diagnostic laboratories. The isolates were confirmed to be S. aureus at our centre. All isolates were subjected to antibiotic susceptibility testing and were screened for methicillin resistance using cefoxitin disc test. All MRSA were subjected to Polymerase Chain Reaction (PCR) assay for detection of mecA and mecC genes. DNA fingerprinting was performed for determining clonal diversity. RESULTS: Seventy-one isolates of 127 confirmed S. aureus were found to be methicillin resistant by screening test. mecA gene was detected in 43 isolates, and none of the isolates were positive for mecC gene. Linezolid and teicoplanin showed better activity with susceptibility pattern being 83.6% and 72.44%, respectively, whereas 66.14% were sensitive to vancomycin. Other antibiotic showed low level of activity. Pulsed Field Gel Electrophoresis (PFGE) showed 14 different banding patterns that suggest isolates were of different clonal types. CONCLUSION: mecA was responsible for methicillin resistance in majority of strains. Polyclonal spread of MRSA infection in the study area indicates its diverse origin and possible lateral transfer. Thus, this study is of clinical interest in terms of selection of proper antimicrobial chemotherapy and infection control management.
BACKGROUND: In Staphylococcus aureus, methicillin resistance is exhibited by modifications in penicillin-binding protein that minimises the binding affinity to beta-lactam antibiotics. The present study investigated the occurrence of methicillin-resistant S. aureus (MRSA) in community-acquired infections, that is, community-acquired MRSA (CA-MRSA) and in-hospital-acquired infections, that is, hospital-acquired MRSA (HA-MRSA) from Northeast India. METHODS: A total of 197 consecutive non-duplicate isolates were collected from Silchar Medical College and Hospital and other private diagnostic laboratories. The isolates were confirmed to be S. aureus at our centre. All isolates were subjected to antibiotic susceptibility testing and were screened for methicillin resistance using cefoxitin disc test. All MRSA were subjected to Polymerase Chain Reaction (PCR) assay for detection of mecA and mecC genes. DNA fingerprinting was performed for determining clonal diversity. RESULTS: Seventy-one isolates of 127 confirmed S. aureus were found to be methicillin resistant by screening test. mecA gene was detected in 43 isolates, and none of the isolates were positive for mecC gene. Linezolid and teicoplanin showed better activity with susceptibility pattern being 83.6% and 72.44%, respectively, whereas 66.14% were sensitive to vancomycin. Other antibiotic showed low level of activity. Pulsed Field Gel Electrophoresis (PFGE) showed 14 different banding patterns that suggest isolates were of different clonal types. CONCLUSION: mecA was responsible for methicillin resistance in majority of strains. Polyclonal spread of MRSA infection in the study area indicates its diverse origin and possible lateral transfer. Thus, this study is of clinical interest in terms of selection of proper antimicrobial chemotherapy and infection control management.
Authors: K Rajaduraipandi; K R Mani; K Panneerselvam; M Mani; M Bhaskar; P Manikandan Journal: Indian J Med Microbiol Date: 2006-01 Impact factor: 0.985
Authors: Aisling T Looney; Elaine J Redmond; Naomi M Davey; Padraig J Daly; Carole Troy; Brian F Carey; Ivor M Cullen Journal: Medicine (Baltimore) Date: 2017-04 Impact factor: 1.889