CLINICAL STUDY ON NOSOCOMIAL INFECTION OF PSEUDOMONAS AERUGINOSA: II. PSEUDOMONAS AERUGINOSA IN THE FECES AND URINARY PSEUDOMONAS AERUGINOSA INFECTION

The present study was designed to assess the role of the bowel as a source of urinary tract infection in patients with Pseudomonas aeruginosa. In investigation of the urological ward in 1976, fecal specimens were obtained from 262 patients. The carriage-rate of P. aeruginosa on admission was 7.8%, and 14.2% of the patients carried that organism when leaving hospital. During the patients' stay in the ward, the carriage-rate increased. It seemed that the increase was perhaps due to a spread of P. aeruginosa from the intestinal tract of one patient to another. Oral administration of antimicrobial agents was an important factor for colonization of P. aeruginosa in the bowel during the patients' stay in the ward. Stools were also examined from the hospital kitchin staff for twelve months, but in contrast with the patients, only a few of them were positive for P. aeruginosa. Oral polymyxin B was effective in eliminating P. aeruginosa, when it was present in the bowel. In 1977 and 1978, polymyxin B was given orally when P. aeruginosa was found in the feces, and the carriage-rate of P. aeruginosa in the bowel when leaving hospital was lower than that in 1976. Most of P. aeruginosa isolated from urine in our ward were typable, and type C, E and G were dominant. Numerous different strains, especially typecially type B, E and G were identified in the feces. But dominant serotypes of P. aeruginosa isolated from urine changed year after year, and the change was coincided with that of P. aeruginosa from feces. In eleven patients, the serotype of P. aeruginosa from urine and feces was identical, and all of them were catheterized in the urinary tract. Patients carrying P. aeruginosa in the bowel seemed to be the source contaminating the hospital environment. Sporadic urinary tract infection by P. aeruginosa might be due to organisms carried by patients in their own gastrointestinal tract. Over 95% of P. aeruginosa isolated from urine and feces produced protease, and over 80% produced elastase. Most of P. aeruginosa were susceptible to gentamicin, tobramycin, amikacin and polymyxin B, and the frequency of gentamicin resistance of that organism was about 10%.