以免疫層析法快速偵測多種血清型腺病毒

Detection of Multiple Serotypes of Adenovirus by Immunochromatographic Test

感染人類的腺病毒(HAdV)有數十種血清型，有些會造成臨床嚴重的感染症，而近年來人類腺病毒已成為常年都會發生感染的病原體，每年流行的腺病毒血清型不盡相同，2011年台灣腺病毒大流行，有些病人更出現較為少見的第7型，臨床上出現多例嚴重下呼吸道感染症，因此提供快速正確的檢驗技術將有助於感染性疾病的鑑別診斷。免疫層析法(immunochromatographic test, ICT)是近年來發展出的呼吸道腺病毒快篩的檢驗技術，本研究利用ICT方法檢測近10年來曾經流行過的各種腺病毒血清型，探討腺病毒ICT試劑對於偵測各種腺病毒血清型的能力，並全面性評估其檢驗性能。研究結果發現，腺病毒CapiliaTM ICT快篩試劑可偵測造成肺炎重症及死亡案例的HAdV-3、HAdV-4、HAdV-7血清型以及台灣曾流行過的腺病毒血清型共13種。CapiliaTM ICT對腺病毒分析敏感度高達10^(-11.83) TCID_50，不會和其他感染呼吸到的病毒產生交叉反應。我們收集2014年期間共874件急性呼吸道感染病人的咽喉拭子檢體，以病毒培養法當成黃金標準，比較CapiliaTM ICT與免疫螢光法（IFA）的臨床檢驗性能。結果顯示CapiliaTM ICT的敏感度優於IFA，分別為62.9%(195/310)和50%(61/122)，兩者特異性皆可達99%；陽性預測值分別為96.8%和98.9%，陰性預測值分別為76.8%和67.2%。本研究顯示CapiliaTM ICT試劑能偵測包括引起重症的多種血清型腺病毒，具有高度的特異性，敏感度優於現行臨床檢驗室常用的IFA技術，而且操作不需特殊設備，短時間內即可獲得結果，可作為腺病毒感染之快篩檢驗，協助臨床醫師對感染性疾病的有效鑑別診斷。

Human adenovirus (HAdV) can cause serious respiratory infections any time of the year and its HAdV serotypes can be different in each year. In 2011, some patients with severe lower respiratory tract infection were detected with rare case of serotype 7 in Taiwan. Therefore providing a reliable testing method is crucial to help physician for differential diagnosis of infectious diseases. Immunochromatographic test (ICT) has been developed recently as a rapid screening test for detecting adenovirus in respiratory tract infection. In this study, a rapid screening ICT was used to assess its capability, sensitivity and specificity in detecting different adenovirus serotypes. The result showed that adenovirus Capilia^(TM) ICT can detect 13 serotypes including HAdV-3、HAdV-4、HAdV-7 which can cause severe pneumonia. We demonstrated that the sensitivity and specificity of Capilia^(TM) are up to 10^(-11.83) TCID_(50) and 100%, respectively. Furthermore, it will not have any cross-reactions with other respiratory viruses. 874 nasopharyngeal swabs were collected from 2014 and viral culture was used as golden standard to assess the clinical effectiveness of IFA and Capilia^(TM). The sensitivity, specificity, positive predictive value and negative predictive value of Immunofluoresent assay (IFA) are 50% (61/122), 99%, 96.8% and 76.8%, and those of Capilia^(TM) are 62.9% (195/310), 99%, 98.9% and 67.2%, respectively. The result from this study indicated that the ICT is capable of detecting different adenovirus serotypes; it provides better sensitivity than IFA system in clinical samples. At the same time, it is low cost, fast and easy to use in comparison with IFA. ICT rapid test can be a good screening tool for specimens with suspected adenovirus infections, but also assist clinicians in differential diagnosis of infectious diseases.