比較螢光單染法與螢光併用Ziehl-Neelsen法對篩檢痰抹片正確性評估

A Comparison of the Accuracy of the Fluorochrome Method Versus a Fluorochrome Plus Ziehl-Neelsen Staining Method for Detecting Mycobacteria in a Sputum Smear

蔡相宜(Shiang-Yi Tsai) ； 林宛如(Wan-Ru Lin) ； 吳佩真(Pei-Chen Wu) ； 李秀霞(Hsiu-Hsia Li) ； 蔡岳廷(Yueh-Ting Tsai) ； 蔡文城(Wen-cherng Tsai)

《檢驗及品保雜誌》 3卷4期 (2014/11) Pp. 153-158

https://doi.org/10.6573/JTQA.201411_3(4).02

摘要

臨床檢體中結核菌的檢驗方法建議，當進行抹片檢體的抗酸性染色時，可先利用敏感性較高的螢光法（flurochrome method, F method）快速篩檢，若鏡檢呈陽性時，再以螢光併用Ziehl-Neelsen法（F+ZN method）進行染色，確認抹片結果是否為真陽性。為了瞭解螢光併用Ziehl-Neelsen法的必要性，因此吾等利用2014年1月1日至2014年5月31日間所收集的16,409件檢體進行分析，在所有檢測檢體的培養結果中分枝桿菌的陽性率佔8.9%（1,458／16,409）。整體而言，MTBC與非結核分枝桿菌（NTM）的比例為43.3%（631／1458）：56.7%（827／1458）。若依據螢光併用Ziehl-Neelsen 法陽性且培養陽性結果進行統計，則MTBC與NTM的比例為61.9%（390／630）：38.1%（240／630），此差異性係因為MTBC較容易由螢光併用Ziehl-Neelsen 法偵測出。另外快速生長NTM、慢速生長NTM及未能鑑定NTM的比例分別為15.8%（38／240）77.5%（186／240）與6.7%（16／240）。又將抹片染色的檢測檢體進行與培養結果的相關性分析，結果指出螢光法的偽陽性高達8.6%，螢光併用Ziehl-Neelsen法的偽陰性為3.1%，偽陽性的結果可能導致病患可能接受不必要的藥物治療，將造成健康受損、經濟損失或導致分枝桿菌抗藥菌株的產生；而偽陰性的結果將造成流行病學上的問題。有鑑於兩種染色方法仍有其偵測極限，檢驗室仍有必要參考分生、免疫學等其它檢測方法，並以檢體培養結果做為診療的「金標準」。

關鍵字

螢光法 ； 螢光併用Ziehl-Neelsen法

並列摘要

One method of testing for mycobacterium tuberculosis complex (MTBC) in clinical specimens recommends that a more sensitive fluorochrome method (F method) should be used when conducting an acid-fast staining method for the rapid screening of MTBC from a sputum smear. If the results of a microscopic examination are positive, the smear will be further stained by Ziehl-Neelsen method (F+ZN method) to confirm whether the positive finding for the smear is true. To understand the necessity of this F+ZN method, we conducted an analysis of 16,409 specimens received from January 1 to May 31, 2014, and found that the positive rate for mycobacteria was 8.9% (1,458/16,409). Among all the specimens we analyzed during the study period, the ratio of MTBC to NTM was 43.3% (631/1458) : 56.7% (827/1458). However, for both the F+ZN method and culturepositive specimens, the ratio of MTBC to NTM was 61.9% (390/630) : 38.1% (240/630). The discrepancy between the above ratios occurred because it is easier to detect the MTBC using the F+ZN method. Additionally, we found that the ratios for rapidly growing NTM, slowly growing NTM and unidentified NTM were 15.8% (38/240), 77.5% (186/240) and 6.7% (16/240), respectively. Analyzing the relationship between different staining methods and culture results, we found that the false positive rate of the F method reached 8.6%, while the false negative rate of the F+ZN method was 3.1%. Generally, false positive results may cause patients to receive unnecessary treatments that could, in turn, result in negative health effects, economic losses for the patient, as well as inducing the production of drug-resistant strains. In contrast, false negative results will lead to epidemiological problems. In order to counteract the limitations of either staining method, laboratory workers should refer to molecular, immunological and other testing methods, and employ the specimen culture results as a gold standard for MTBC diagnosis and treatment.

並列關鍵字

Fluorochrome Method ； Fluorochrome Plus Ziehl-Neelsen Method