Burckhardt F, Warner P, Young H
Bavarian Health and Food Safety Authority (Public Health), Veterinaerstr. 2, 85764 Oberschleissheim, Germany.
Sex Transm Infect. 2006 Feb;82(1):24-30. doi: 10.1136/sti.2004.011882.
To describe the impact of change from culture to more sensitive nucleic acid amplification testing (NAAT) tests on the detection of Chlamydia trachomatis in a genitourinary medicine (GUM) clinic population.
Data were collected between January 1992 and December 2003 on results of C trachomatis tests on male and female attenders at the Lothian GUM clinic (n = 81 590). Routine diagnosis switched from culture to NAAT methods in September 1998. Association of test result with age, sex, year of test, and test type was analysed using logistic regression.
6.1% (95% CI: 5.7% to 6.5%) of women and 7.1% of men (95% CI: 6.7% to 7.5%) tested positive with culture and 9.9% of women (95% CI: 9.4% to 10.3%) and 11.1% of men (95% CI: 10.7% to 11.5%) tested positive with NAATs. This corresponds to a 56% increase for men (95% CI: 47% to 66%) and 62% for women (95% CI: 50% to 67%). Logistic regression showed that a positive test result was strongly associated with test type with or without adjustment for year of test, sex, and young age.
The significant increase in chlamydial infections detected following a change from culture to NAATs has important implications for interpretation of trends ascertained from surveillance data. Not all of this can be a direct effect of enhanced sensitivity and there may be indirect effects that improve ascertainment of existing infections. As more laboratories switch to NAATs similar patterns of stepwise increases in positive results are expected and trend analysis based on such surveillance data might thus show an artefactual rise in chlamydia infection rates. Accumulated surveillance data should therefore include timing of introduction of NAAT, so as to take account of under-ascertainment by previous methods.
描述从培养法改为更灵敏的核酸扩增检测（NAAT）法对泌尿生殖医学（GUM）门诊人群沙眼衣原体检测的影响。
收集了1992年1月至2003年12月期间洛锡安GUM门诊男性和女性就诊者沙眼衣原体检测结果的数据（n = 81590）。1998年9月，常规诊断方法从培养法改为NAAT法。使用逻辑回归分析检测结果与年龄、性别、检测年份和检测类型之间的关联。
采用培养法检测时，6.1%（95%可信区间：5.7%至6.5%）的女性和7.1%的男性（95%可信区间：6.7%至7.5%）检测呈阳性；采用NAAT法检测时，9.9%的女性（95%可信区间：9.4%至10.3%）和11.1%的男性（95%可信区间：10.7%至11.5%）检测呈阳性。这相当于男性阳性率增加了56%（95%可信区间：47%至66%），女性增加了62%（95%可信区间：50%至67%）。逻辑回归显示，无论是否对检测年份、性别和年轻年龄进行调整，阳性检测结果都与检测类型密切相关。
从培养法改为NAAT法后，沙眼衣原体感染检测阳性率显著增加，这对根据监测数据确定的趋势解读具有重要意义。这并非全部是灵敏度提高的直接影响，可能存在改善现有感染确诊率的间接影响。随着更多实验室改用NAAT法，预计阳性结果会有类似的逐步增加模式，因此基于此类监测数据的趋势分析可能会显示沙眼衣原体感染率出现人为上升。因此，累积的监测数据应包括引入NAAT法的时间，以便考虑到先前方法导致的确诊不足情况。
