A presumptive diagnosis of tuberculosis in bone and joint can be made on the basis of patient's history, clinical and radiologic findings, and the presence of AFB in the patient's specimen. Microscopic examination by Ziehl-Neelsen stain for AFB
is
the
most rapid method for detection of M. tuberculosis, but it is insensitive and nonspecific. Laboratory cultures of M. tuberculosis are cumbersome and time consuming. For that reason, the development of a more rapid method to diagnose the
tuberculosis of
bone and joint is highly desirable. We have utilized PCR method in order to detect M. tuberculosis and compare with conventional smear and culture method. We used 30 paraffin block specimens of clinically and pathologically suspected bone and
joint
tuberculosis between 1991 and 1994.
@ES The results were as follows:
@EN 1. The sensitivity of IS986, nested-PCR method under the condition of this experiment was 0.5 fg.
2. Seven (23.3%) out of thirty biopsy specimen were positive by AFB stain.
3. By PCR method, 19(63.3%) of the 30 paraffin-embedded biopsy specimens were positive for M. tuberculosis DNA. 10(43.5%) of 23 AFB-negative cases were positive for M. tuberculosis DNA. Six(85.7%) of seven AFB-positive biopsy specimens and
four(57.1%)
of seven AFB-positive pus material positive for M. tuberculosis DNA.
4. By PCR method, 10(58.8%) out of 17 AFB negative cases in biopsy specimen and pus material were positive for M. tuberculosis DNA.
5. By pus-AFB stain, sensitivity were 20%, specificity were 70% ; by biosy-specimen-AFB stain, sensitivity 27.2%, specificity 87.5% ; by PCR method, sensitivity 70%, specificity 41%.
The PCR results in paraffin-embedded specimen were found to have higher positive rate than AFB stain. These findings suggest that DNA amplification by PCR may be used for direct detection of M. tuberculosis from clinical fresh and paraffin
embedded
tissue specimens. The PCR is an especially useful technique in the demonstration of mycobaterial DNA fragment in patients with clinically suspected tuberculosis, showing acid fast bacilli stain-negative granulomatous lesion, microscopically.
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