呼吸道病毒感染之實驗診斷

Laboratory Diagnosis of Viral Respiratory Infections

呼吸道病毒感染可由無症狀、輕症至重症甚而死亡，臨床醫師困難從病人症狀去正確地區分病毒致病原，因此準確的識別這些感染原和適當地照護患者的健康是醫療體系首項任務。呼吸道病毒的檢測方法日新月異，由數十年前的傳統培養鑑定法到快速抗原檢測，演變至最近的核酸擴增檢測方法（nucleic acid amplification tests, NAAT）與即時定點照護核酸檢測法（point of care nucleic acid testing, POCT）。雖然NAAT和POCT的高敏感度與特異性對臨床診斷有非常大之助益，但其試劑成本相較傳統方法昂貴且無法大量繁殖活的病毒做進一步的分析研究。因此病毒培養鑑定、偵測病毒顆粒和抗原的傳統方法在實驗室仍有其存在的必要性。因此本篇的重點則是介紹現今實驗室檢測呼吸道病毒的方法和討論該方法的優缺點。

Viral respiratory infections can be asymptomatic or result in mild-to-severe clinical symptoms or even death. Clinicians find it difficult to correctly identify viral pathogens based on patients' respiratory symptoms. Accurate identification of these infectious agents is vital in providing effective care for these patients. The methods for respiratory virus detection are changing rapidly, from the traditional culture and identification method to the rapid antigen tests developed decades ago, to the recent nucleic acid amplification tests (NAAT) and point-of-care nucleic acid tests (POCT). Although the high sensitivity and specificity of NAAT and POCT are very helpful for clinical diagnosis, their reagent costs are high compared with traditional methods and they cannot proliferate live viruses for further analysis. Consequently, the traditional methods of viral culture and detection of virus particles and antigens are still necessary in the laboratory. Therefore, the focus of this article is to introduce current laboratory tests for detecting respiratory viruses and discuss the advantages and disadvantages of these tests.