最近の入院患者における尿路感染の諸相 - ことにhospital-acquired,catheter-associated bacteriuriaについて -

Abstract

In a survey of urinary tract infections at the Kyoto University Hospital, gram-negative bacilli were accounted for 86.7% in 1974 and 64.0% in 1970, of microorganism isolated from urine specimens. Incidence of E. coli did not change and that of Pseudomonas and Proteus group increased in those years. Modes of urinary tract infections in hospitalized patients were characterized by indwelling catheter to the urinary tract. E. coli and Klebsiella were mainly isolated from urines without indwelling catheter. However, Pseudomonas, Proteus group, Citrobacter and Enterobacter were frequently isolated from urines with indwelling catheter. Under administration of anitibiotics, frequency of E. coli decreased and that of Klebsiella, Pseudomonas and Enterobacter increased in urines from the non-catheterized patients. During hospitalization, colonizations were mostly seen among gram-negative bacilli. Secondary isolated bacilli consisted of Pseudomonas, Enterbacter and Citrobacter. Stones, tumors, urinary stasis and VUR, as predisposing factors for urinary tract infections, were not always attributed to significant bacteriuria. However, the indwelling catheter induced bacteriuria and gave rise to characteristic bacillous spectrum of urinary tract infections in hospitalized patients. Risk factos for urinary tract infections with indwelling catheter were analyzed and preventive methods for bacteriuria were discussed. It was assumed that a cross-contamination between patients through medical personell played a role in hospital-acquired, catheterassociated, bacteriuria.