title: Evaluation of various methods for the detection of meticillin-resistant Staphylococcus aureus strains and susceptibility patterns.
abstract: Meticillin-resistant Staphylococcus aureus (MRSA) has been recognized as one of the major pathogens in hospital as well as community settings. In India, the mean isolation rate of MRSA is 20-40 % and many studies have suggested an escalating rate of infections caused by this organism. Despite pharmaceutical and technological advancement, infections caused by MRSA still remain difficult to diagnose. The present study was undertaken to compare five phenotypic methods for the detection of MRSA. This involved examining 200 isolates of S. aureus by oxacillin disc diffusion, cefoxitin disc diffusion, oxacillin screen agar test, the latex agglutination test and growth on CHROMagar. PCR for mecA gene detection was taken as the gold standard. It was found that 35 % of all S. aureus infections were caused by MRSA. The cefoxitin disc diffusion method, as recommended by the Clinical and Laboratory Standards Institute, was found to be a reliable method for MRSA detection but it should be supplemented with some other method like latex agglutination, CHROMagar or oxacillin screen agar testing so that no MRSA is missed. We recommend that along with cefoxitin disc diffusion, another method, preferably latex agglutination, should be routinely used in all hospitals to detect MRSA.
authors.affiliation: Department of Microbiology, Government Medical College Hospital, Chandigarh, India.
authors.forename: Priya
authors.initials: P
authors.lastname: Datta
authors.affiliation: Department of Microbiology, Government Medical College Hospital, Chandigarh, India.
authors.forename: Neelam
authors.initials: N
authors.lastname: Gulati
authors.affiliation: Department of Microbiology, Government Medical College Hospital, Chandigarh, India.
authors.forename: Nidhi
authors.initials: N
authors.lastname: Singla
authors.affiliation: Department of Microbiology, Government Medical College Hospital, Chandigarh, India.
authors.forename: Hena
authors.initials: H
authors.lastname: Rani Vasdeva
authors.affiliation: Department of Microbiology, Government Medical College Hospital, Chandigarh, India.
authors.forename: Kiran
authors.initials: K
authors.lastname: Bala
authors.affiliation: Department of Microbiology, Government Medical College Hospital, Chandigarh, India.
authors.forename: Jagdish
authors.initials: J
authors.lastname: Chander
authors.affiliation: Department of Microbiology, Government Medical College Hospital, Chandigarh, India.
authors.forename: Varsha
authors.initials: V
authors.lastname: Gupta
mesh_terms: D006801:Humans; D005779:Immunodiffusion / Q000379:methods* / Q000592:standards; D007194:India; D007841:Latex Fixation Tests / Q000379:methods* / Q000592:standards; D055624:Methicillin-Resistant Staphylococcus aureus / Q000302:isolation & purification*; D008826:Microbial Sensitivity Tests; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D013203:Staphylococcal Infections / Q000175:diagnosis* / Q000382:microbiology