Stamm W E, McKevitt M, Roberts P L, White N J
Department of Medicine, University of Washington School of Medicine, Seattle.
Rev Infect Dis. 1991 Jan-Feb;13(1):77-84. doi: 10.1093/clinids/13.1.77.
To evaluate the natural history of uncomplicated urinary tract infections in women, we observed 51 infection-prone women in a standardized fashion for a median of 9 years. During intervals when patients were not receiving antimicrobial prophylaxis, infections occurred at an average rate of 2.6 per patient-year, but the rate varied widely from patient to patient (range 0.3-7.6 episodes per year). Seventy-three percent of the observed episodes were symptomatic, with an 18:1 ratio of cystitis to pyelonephritis episodes. Infectious episodes were strikingly clustered, and rates of infection decreased in the winter months. Antimicrobial prophylaxis was highly effective in preventing acute cystitis, asymptomatic bacteriuria, and acute pyelonephritis, even when used for as long as 5 years. The proportions of infecting strains resistant in vitro to ampicillin (19%-32%) and nitrofurantoin (5%-18%) were unchanged over the 15-year observation period, while resistance to trimethoprim-sulfamethoxazole increased in the last 5 years of the study.
为评估女性单纯性尿路感染的自然病史，我们以标准化方式观察了51名易感染女性，中位观察时间为9年。在患者未接受抗菌药物预防期间，感染发生率平均为每人每年2.6次，但患者之间的发生率差异很大（范围为每年0.3 - 7.6次发作）。观察到的发作中有73%有症状，膀胱炎与肾盂肾炎发作的比例为18:1。感染发作明显聚集，冬季感染率下降。抗菌药物预防在预防急性膀胱炎、无症状菌尿和急性肾盂肾炎方面非常有效，即使使用长达5年也是如此。在15年的观察期内，体外对氨苄西林耐药的感染菌株比例（19% - 32%）和对呋喃妥因耐药的比例（5% - 18%）没有变化，而在研究的最后5年中，对甲氧苄啶 - 磺胺甲恶唑的耐药性增加。
