Stark R P, Maki D G
N Engl J Med. 1984 Aug 30;311(9):560-4. doi: 10.1056/NEJM198408303110903.
We studied 110 catheterized patients to determine the concentration of microorganisms that would indicate infection in urine aspirated from an indwelling urethral catheter. High-level bacteriuria or candiduria (greater than 10(5) colony-forming units per milliliter) developed in 34 patients. However, low-level bacteriuria or candiduria (less than 10(5) organisms per milliliter), which developed in 41 patients, progressed to concentrations above 10(5) organisms per milliliter 96 per cent of the time (P less than 0.001), usually within three days of the initial culture showing growth, unless the patient received intercurrent suppressive antimicrobial therapy. We conclude that the urinary tract of catheterized patients is highly susceptible to infection once small numbers of microorganisms gain access and that a concentration considerably below 10(5) organisms per milliliter may be clinically and epidemiologically important in this setting.
我们研究了110例留置导尿的患者，以确定从留置尿道导管吸出的尿液中提示感染的微生物浓度。34例患者出现了高浓度菌尿或念珠菌尿（每毫升大于10⁵菌落形成单位）。然而，41例患者出现了低浓度菌尿或念珠菌尿（每毫升少于10⁵个微生物），其中96%的患者在初次培养显示有生长后的三天内，菌尿浓度进展至每毫升超过10⁵个微生物（P小于0.001），除非患者接受了同时进行的抑制性抗菌治疗。我们得出结论，一旦少量微生物进入，留置导尿患者的尿路极易受到感染，在这种情况下，每毫升低于10⁵个微生物的浓度在临床和流行病学上可能具有重要意义。
