The clinical utility of polymerase chain reaction for the diagnosis of pleural tuberculosis.
BACKGROUND
There is no exact consensus about the usefulness of the Mycobacterium tuberculosis polymerase chain reaction (PCR) testing for the diagnosis of tuberculous pleural effusion because of the diverse PCR methods and the different diagnostic criteria that are described in other studies.


METHODS
We analyzed pleural effusion specimens obtained from 111 patients for whom the exclusion of the possibility of tuberculous pleural effusion was necessary. We performed M. tuberculosis PCR testing using the Cobas Amplicor MTB test (Roche Diagnostic Systems), which is fully automated and commercially available.


RESULTS
Results of the M. tuberculosis PCR test of pleural effusion specimens were positive for 7 (17.1%) of the 41 patients with confirmed pleural tuberculosis and for 3 (18.8%) of the 16 patients with probable pleural tuberculosis. The overall sensitivity and specificity of M. tuberculosis PCR testing of pleural effusion were 17.5% and 98.1%, respectively. The sensitivity of M. tuberculosis PCR testing for each group of patients with tuberculous pleural effusion detected by smear-positive results, smear-negative and culture-positive results, and culture-negative and pleural biopsy-positive results, was 100.0%, 33.3%, and 3.7%, respectively. Of the 57 patients with pleural tuberculosis, only 3 (5.3%) had positive results of M. tuberculosis PCR testing along with negative results of smearing, negative results of pleural pathological analysis, and a low level of adenosine deaminase.


CONCLUSIONS
For specimens such as pleural effusion, in which the bacillary load is very low, the clinical utility of PCR testing seems highly limited.
Moon
Jin Wook
JW
Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea.
Chang
Yoon Soo
YS
Kim
Se Kyu
SK
Kim
Young Sam
YS
Lee
Hyuk Min
HM
Kim
Sung Kyu
SK
Chang
Joon
J
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction / Q000379:methods*; D012680:Sensitivity and Specificity; D013997:Time Factors; D014396:Tuberculosis, Pleural / Q000175:diagnosis*