Pilcher Christopher D, Fiscus Susan A, Nguyen Trang Q, Foust Evelyn, Wolf Leslie, Williams Del, Ashby Rhonda, O'Dowd Judy Owen, McPherson J Todd, Stalzer Brandt, Hightow Lisa, Miller William C, Eron Joseph J, Cohen Myron S, Leone Peter A
Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, USA.
N Engl J Med. 2005 May 5;352(18):1873-83. doi: 10.1056/NEJMoa042291.
North Carolina has added nucleic acid amplification testing for the human immunodeficiency virus (HIV) to standard HIV antibody tests to detect persons with acute HIV infection who are viremic but antibody-negative.
To determine the effect of nucleic acid amplification testing on the yield and accuracy of HIV detection in public health practice, we conducted a 12-month observational study of methods for state-funded HIV testing. We compared the diagnostic performance of standard HIV antibody tests (i.e., enzyme immunoassay and Western blot analysis) with an algorithm whereby serum samples that yielded negative results on standard antibody tests were tested again with the use of nucleic acid amplification. A surveillance algorithm with repeated sensitive-less-sensitive enzyme immunoassay tests was also evaluated. HIV infection was defined as a confirmed positive result on a nucleic acid amplification test or as HIV antibody seroconversion.
Between November 1, 2002, and October 31, 2003, 109,250 persons at risk for HIV infection who had consented to HIV testing presented at state-funded sites. There were 606 HIV-positive results. Established infection, as identified by standard enzyme immunoassay or Western blot analysis, appeared in 583 participants; of these, 107 were identified, with the use of sensitive-less-sensitive enzyme immunoassay tests, as recent infections. A total of 23 acutely infected persons were identified only with the use of the nucleic acid amplification algorithm. With all detectable infections taken into account, the sensitivity of standard antibody testing was 0.962 (95 percent confidence interval, 0.944 to 0.976). There were two false positive results on nucleic acid amplification tests. The specificity and positive predictive value of the algorithm that included nucleic acid amplification testing were greater than 0.999 (95 percent confidence interval, 0.999 to >0.999) and 0.997 (95 percent confidence interval, 0.988 to >0.999), respectively. Of the 23 acute HIV infections, 16 were detected at sexually transmitted disease clinics. Emergency measures for HIV prevention protected 48 sex partners and one fetus from high-risk exposure to HIV.
The addition of nucleic acid amplification testing to an HIV testing algorithm significantly increases the identification of cases of infection without impairing the performance of diagnostic testing. The detection of highly contagious, acutely infected persons creates new opportunities for HIV surveillance and prevention.
北卡罗来纳州已在标准的人类免疫缺陷病毒（HIV）抗体检测中增加了核酸扩增检测，以检测处于急性HIV感染期、病毒血症阳性但抗体阴性的患者。
为了确定核酸扩增检测对公共卫生实践中HIV检测的检出率和准确性的影响，我们进行了一项为期12个月的关于州政府资助的HIV检测方法的观察性研究。我们将标准HIV抗体检测（即酶免疫测定和免疫印迹分析）的诊断性能与一种算法进行了比较，该算法是对在标准抗体检测中呈阴性结果的血清样本再次使用核酸扩增进行检测。还评估了一种采用重复的敏感性较低的酶免疫测定检测的监测算法。HIV感染定义为核酸扩增检测确诊为阳性结果或HIV抗体血清学转换。
在2002年11月1日至2003年10月31日期间，109,250名同意接受HIV检测的HIV感染风险人群在州政府资助的检测点接受了检测。有606例HIV阳性结果。通过标准酶免疫测定或免疫印迹分析确定的已确诊感染出现在583名参与者中；其中，107例通过敏感性较低的酶免疫测定检测被确定为近期感染。仅使用核酸扩增算法共识别出23例急性感染患者。将所有可检测到的感染情况考虑在内，标准抗体检测的敏感性为0.962（95%置信区间为0.944至0.976）。核酸扩增检测有两例假阳性结果。包括核酸扩增检测的算法的特异性和阳性预测值分别大于0.999（95%置信区间为0.999至>0.999）和0.997（95%置信区间为0.988至>0.999）。在23例急性HIV感染中，16例在性传播疾病诊所被检测到。HIV预防紧急措施保护了48名性伴侣和1名胎儿免于高危HIV暴露。
在HIV检测算法中增加核酸扩增检测可显著提高感染病例的识别率，同时不影响诊断检测的性能。检测出具有高度传染性的急性感染患者为HIV监测和预防创造了新的机会。
