[Hospital acquired infection in surgical field and its countermeasure present situation of anaerobes, P. aeruginosa and MRSA infection].

The important organisms of hospital acquired infection in surgical field are anaerobes, P. aeruginosa and MRSA. From 1977, isolation frequency of anaerobes from pus has been increasing remarkably and it became 60% in 1978. The isolation rates of P. aeruginosa increased 20 to 30%. Since 1988, the incidence of isolation of MRSA has increased markedly. Almost of all the coagulase typing of MRSA were type II, and it suggested the possibility of hospital infection. In 1988, high antimicrobial activity against MRSA was observed with vancomycin, imipenem, minocycline and new quinolones, but in 1990 the multiresistant strains against imipenem, minocycline and new quinolones were increased. Among the various antimicrobial agents examined, vancomycin demonstrated the strongest activity to MRSA. The symptomatic infections were postoperative enterocolitis, respiratory infection, biliary tract infection and wound infection. The most severe symptom was observed in MRSA enterocolitis. We conducted a nation wide questionnaire of postoperative enterocolitis from January 1988 to June 1990. 169 institutes replied, and 126 cases were involved in postoperative MRSA enterocolitis in 53 institutes. Eighteen cases died, and mortality rate was 14.3%. In the treatment of MRSA infection vancomycin was the most effective antibiotics. It is the most important to prevent nosocomial infection.