The incidence of multidrug-resistant strains of Staphylococcus aureus continues to increase in hospitals and the community all over the world. As the importance of miner surgery in dentistry gets greater recently, the frequency in use of antibiotics has been increasing. Although several cases of acquired infection in oral cavity in dental hospital has been reported, the research on isolation of S. aureus and evaluation of its antibiotic resistance from outpatients in the dental clinic has not been found yet. The aim of this study was to evaluate the antimicrobial resistance of S. aureus isolates. The isolation rate of S. aureus were 41.7% in dental hospital personnel, 60.4% in outpatients and 62% in dental hygiene students. S. aureus which showed resistance to penicillin were 88.6%, ampicillin 88.6%, erythromycin 8.6%, tetracycline 4.3%, oxacillin 4.3%, cefoteten 4.3%. Six strains of S. aureus showed the susceptible to all antibiotics tested. Sixty-four(91.4%) strains were multiple antibiotic resistance. Fifty-two strains(72.8%) resisted to AM-P. and Seven strains(10.0%) resisted to AM-P-E, AM-P-GM, AM-P-TE.

In order to investigate phenotype and genotype of Salmonella enterica subsp. enterica serovar Enteritidis, Forty-eight S. Enteritidis isolates from diarrhea patients were analysed using antimicrobial resistance typing, Phage typing, and Pulsed field gel electrophoresis in Seoul from 2004 to 2005. All of S. Enteritidis were resistant to streptomycin(SM, 37.5%), ampicillin(AM, 43.8%), t icarcillin(TIC, 43.8%), chloramphenicol(CM, 29.2%), t etracycline(TE, 10 .4%) and nalidixic acid(NA, 18.8%) among 16 antimicrobial drugs. Of 48 S. Enteritidis, 8 isolates(16.7%) were resistant to 1 drug, 3 isolates( 6.3%) to 2 drugs, 1 isolate (2.1%) to 3 drugs and 17 isolates(35.7%) to 4 drugs. The basic pattern of 4 drugs resistance was SM, TIC, TE, and CM but 1 drug resistant isolates represent all nalidixic acid resistance. Among 30 antibiotic r esistant S . Enteritidis, 2 1 isolates(70 %) were phage type 2 1, 8 i solates(26.7%) were phage t ype 2 3 and 1 isolate( 3.3%) was RDNC, respectively. Of the phage types observed, all of phage type 23(8 isolates) were nalidixic acid resistant and phage type 21 were AM-TIC-SM-CM multi-resistance(13 isolates; 43.3%), AM-TIC-SM-TE(4 isolates; 13.3%), AM-TIC-SM(1 isolate; 3.3%), AM-TIC-CM(1 isolate; 3.3%), and AM-TIC(2 isolates; 6.7%) resistance and 1 isolate of RDNC was NA-TE resistance. PFGE divided the isolates into two major clusters, A(n=14) and B(n=14). There were four different resistance profiles with resistance to AM, TIC, SM, TE, NA within PFGE A. Also resistance to AM, TIC, SM, CM was common within PFGE B. The PFGE A strains typed as PT21(n=5), PT23(n=8), and RDNC(n=1), While all the PFGE B strains typed as PT21(n=14). In consequence, there was the highly significant concurrence between resistance typing, phage typing and PFGE.

Methic illin - resistant StaphyJococcus aureus(MRSA) is not only a common cause of nosocomial infections worldwide but also leading to seri ous illnesses with high rates of mortali ty , This study was performed to determine resistance patterns and molecul ar biological ca racteri slics on MRSA isolated from clinical specimen, The purpose is to provide valua ble in formation related to t he purs uit 0 (' in('ec tion trace and infe<:tion control The test of susceptibility to 17 kinds antibiotics showed that these bacterias were susceptible to glycope ptides s uch as vancomycin, teicoplanin by 100%, rifarnpin by 65, 8%, They we re a lso 100% resistance to peni cillin , cefotaxim, gentamycin and aminoglycoside drugs , and showed 68, 56% multidrug res is ta nce to a bove 13 a ntibi oti cs incl uding peni cillin, 1n the analysis of MRSA using PCR, mecA was detected in every MRSA at 35 s t ra i ns a nd l'emA in 94 1%, ln a test , to de tect toxic genes, six genes, such as sea, seb(8, 6% res pectively)‘ sec(51, 4%) ‘ seg, se i(65 , 7% res pectively) and seh(2 , 9%) were found Finally , in resisrance chract eristics, toxic genes we re isola ted c1 ifferently acco rcling to specimen but there was no c1ifference res istance pattern ancl toxic genes The c1ata from t his s t ucly contribule to a more prec ise knowledge about the resistance pa ttern of MRSA in a clinical sett ing in k orea ancl regarcl exa mi na ti on of resis ta nce pattern accorcling to molecular biological methocl are expectecl to provide bas ic informa ti on on MRSA di ssemination and infection contro