Grun L, Tassano-Smith J, Carder C, Johnson A M, Robinson A, Murray E, Stephenson J, Haines A, Copas A, Ridgway G
Department of Sexually Transmitted Diseases, University College London Medical School.
BMJ. 1997 Jul 26;315(7102):226-30. doi: 10.1136/bmj.315.7102.226.
To estimate the prevalence of Chlamydia trachomatis in asymptomatic women attending general practice: to assess the potential of the ligase chain reaction as a screening tool; and to evaluate selective screening criteria.
Cross sectional survey.
Four general practices in northeast London.
890 women aged 18-35 years attending general practice for a cervical smear or a "young well woman" check between October 1994 and January 1996. The women were tested for C trachomatis with confirmed enzyme immunoassay (endocervical specimens) and ligase chain reaction assay on urine specimens.
Prevalence of C trachomatis infection in women aged 18-35 on the basis of each test; sensitivity and specificity of both tests in this population.
Prevalence of confirmed infection was 2.6% (95% confidence interval 1.6% to 3.6%) in all women. Prevalence on the basis of enzyme immunoassay was 1.6% (0.8% to 2.7%), with a sensitivity of 60% and a specificity of 100%. Prevalence on the basis of ligase chain reaction was 2.5% (1.5% to 3.9%), with 90% sensitivity and 99.8% specificity. Screening all women aged < or = 25 and all women who had had two or more partners in the past year would have detected 87% (20/23) of infections.
Ligase chain reaction on urine samples performs at least as well as enzyme immunoassay on cervical specimens in this low prevalence population. It offers potential as a non-invasive screening tool. A simple selective screening strategy might be appropriate and would be able to detect most cases of infection. However, a rigorous economic evaluation of possible screening strategies is needed first.
评估全科医疗中无症状女性沙眼衣原体的感染率；评估连接酶链反应作为筛查工具的潜力；并评估选择性筛查标准。
横断面调查。
伦敦东北部的四家全科医疗机构。
1994年10月至1996年1月期间因宫颈涂片检查或“年轻健康女性”检查而到全科医疗就诊的890名18至35岁女性。对这些女性进行了沙眼衣原体检测，采用确诊酶免疫测定法（宫颈管内标本）和尿液标本连接酶链反应测定法。
基于每种检测方法的18至35岁女性沙眼衣原体感染率；两种检测方法在该人群中的敏感性和特异性。
所有女性中确诊感染率为2.6%（95%置信区间为1.6%至3.6%）。基于酶免疫测定法的感染率为1.6%（0.8%至2.7%），敏感性为60%，特异性为100%。基于连接酶链反应的感染率为2.5%（1.5%至3.9%），敏感性为90%，特异性为99.8%。对所有年龄≤25岁的女性以及过去一年有两个或更多性伴侣的所有女性进行筛查，可检测出87%（20/23）的感染病例。
在该低感染率人群中，尿液样本连接酶链反应的检测效果至少与宫颈标本酶免疫测定法相同。它有望成为一种非侵入性筛查工具。一种简单的选择性筛查策略可能是合适的，并且能够检测出大多数感染病例。然而，首先需要对可能的筛查策略进行严格的经济学评估。
