만성 육아종성 염증에서 파라핀 포매 조직을 이용한 결핵균 PCR 검사와 Ziehl-Neelsen 염색의 비교 분석

Abstract

Background : TB-PCR is a faster and more sensitive method to detect mycobacterium than acid-fast bacilli (AFB) stain, which is laborious and time consuming. We compared the sensitivity and specificity of AFB stain and TB-PCR and examined the possibility of TB-PCR as a confirmative test without AFB stain in the diagnosis of tuberculosis. Methods : We performed Ziehl-Neelsen stain and nested PCR using a commercially available TB-PCR kit amplifying IS6110 sequence in 81 cases of paraffin-embedded tissues diagnosed as chronic granulomatous inflammation. In addition, we evaluated the morphology of granuloma and the presence of caseation necrosis. Results : Of the 81 cases studied, 22 (27.2%) and 40 (49.4%) were positive for AFB stain and TB-PCR, respectively. Of 49 cases accompanying caseation necrosis, 19 (38.8%) were AFB stain positive and 37 (75.5%) were TB-PCR positive; a result that is comparable with that of other reports. Of the 22 AFB-positive cases, 2 were TB-PCR negative. Conclusion : TB-PCR is very helpful for the diagnosis of tuberculosis in routinely processed, formalin- fixed, paraffin-embedded tissue samples. Nevertheless, AFB stain should continue to be performed at the same time.