Berk R H, Yazici M, Atabey N, Ozdamar O S, Pabuccuoglu U, Alici E
School of Medicine, Department of Orthopaedics and Traumatology, Dokuz Eylul University, Izmir, Turkey.
Spine (Phila Pa 1976). 1996 Sep 1;21(17):1991-5. doi: 10.1097/00007632-199609010-00011.
Twenty-five formaldehyde solution-fixed, paraffin-embedded tissue blocks from vertebral biopsy specimen materials with presumptive diagnosis of tuberculous spondylitis and nonspecific vertebral osteomyelitis were studied.
To evaluate the sensitivity and specificity of polymerase chain reaction in detecting Mycobacterium tuberculosis in formaldehyde solution-fixed, paraffin-embedded tissue samples from histologically proved tuberculous spondylitis.
Diagnosis of a mycobacterial infection is a long and tedious process; because of the slow growth rate of mycobacteria on solid media, identification and antibiotic sensitivity testing can take up to 10 weeks, but the sensitivity of culture can be as low as 50%. Direct microscopy is insensitive because clinical samples may contain only few organisms. Recently, polymerase chain reaction has been applied in the rapid amplification and identification of many organisms, including mycobacteria.
The DNAs were extracted from 25 paraffin-embedded tissue blocks. An insertion element IS 6110 (Integrated DNA Tec. Inc., Corrallville, IA), a DNA sequence unique to Mycobacterium complex (M. tuberculosis and the subspecies Mycobacterium bovis), was amplified by polymerase chain reaction. Polymerase chain reaction results were compared with those of Mycobacterium culture, acid-fast bacilli staining, and histologic findings.
Polymerase chain reaction was positive in 18 cases of 19 tuberculous spondylitis. Three of the polymerase chain reaction test results were positive with concomitant negative culture and positive acid-fast bacilli staining. There were six chronic nonspecific infections, and polymerase chain reaction results were negative in five cases; in the single positive case, DNA amplification results remained positive even after three repeated tests.
Polymerase chain reaction has a sensitivity of 94.7%, specificity of 83.3%, positive predictive value of 94.7%, and a negative predictive value of 83.3%. Accuracy was calculated as 92%.
对25个来自椎骨活检标本材料的甲醛溶液固定、石蜡包埋组织块进行研究，这些标本初步诊断为结核性脊柱炎和非特异性椎体骨髓炎。
评估聚合酶链反应在检测经组织学证实的结核性脊柱炎的甲醛溶液固定、石蜡包埋组织样本中结核分枝杆菌的敏感性和特异性。
分枝杆菌感染的诊断是一个漫长而繁琐的过程；由于分枝杆菌在固体培养基上生长缓慢，鉴定和抗生素敏感性测试可能需要长达10周的时间，但培养的敏感性可能低至50%。直接显微镜检查不敏感，因为临床样本中可能只含有少量微生物。最近，聚合酶链反应已应用于许多生物体的快速扩增和鉴定，包括分枝杆菌。
从25个石蜡包埋组织块中提取DNA。通过聚合酶链反应扩增插入元件IS 6110（Integrated DNA Tec. Inc.，科拉尔维尔，爱荷华州），这是结核分枝杆菌复合群（结核分枝杆菌和牛分枝杆菌亚种）特有的DNA序列。将聚合酶链反应结果与分枝杆菌培养、抗酸杆菌染色和组织学检查结果进行比较。
19例结核性脊柱炎中有18例聚合酶链反应呈阳性。3例聚合酶链反应检测结果为阳性，同时培养阴性但抗酸杆菌染色阳性。有6例慢性非特异性感染，5例聚合酶链反应结果为阴性；在单个阳性病例中，即使经过三次重复检测，DNA扩增结果仍为阳性。
聚合酶链反应的敏感性为94.7%，特异性为83.3%，阳性预测值为94.7%，阴性预测值为83.3%。计算得出的准确率为92%。
