Tuberc Respir Dis.  2001 Feb;50(2):213-221. 10.4046/trd.2001.50.2.213.

Clinical Utility of Bronchial Washing PCR for IS6110 and Amplicor for the Rapid Diagnosis of Active Pulmonary Tuberculosis in Smear Negative Patients

• Lee J
• Kim Y
• Park J
• Ko W
• Yang D
• Kim S
• Chang J
• Kim S
• Choi J

• KMID: 2318301
• DOI: http://doi.org/10.4046/trd.2001.50.2.213

Abstract

BACKGROUND
There is a well recognized interlaboratory variation in the results using the polymerase chain reaction(PCR) to detect the IS6110 sequence. The clinical utility of a commercially developed PCR test(Amplicor) in bronchial washings for detecting pulmonary tuberculosis in smear negative patients was evaluated. The sensitivity and specificity of Amplicor was compared with that of an in-house PCR test used for detecting the IS6110 sequence of Mycobacterium tuberculosis(M.tbc) in the bronchial washing fluid.
METHODS
66 patients whose sputum smear for M.tbc were negative or who could not produce any sputum were recruited from January 1999 to July 1999. They all had a bronchoscopy performed to determine if there were signs of hemoptysis, patients who could not cough up sputum, lung lesion that exclude pulmonary tuberculosis. Pulmonary tuberculosis was diagnosed on the basis of a positive culture or a response to anti-tuberculosis therapy.
RESULTS
19 patients with tuberculosis were identified and samples from 16 patients were later confirmed by culture. Bronchial washing for Amplicor PCR revealed a sensitivity, specificity, positive and negative predictive values of 94.7%, 97.9%, 94.7%, 97.9%, respectively. Using IS6110 based PCR, the sensitivity, specificity, positive and negative predictive values were of 73.7%, 87.2%, 70%, 89.1% respectively.
CONCLUSION
Bronchial washing for Amplicor PCR proved to be more useful than IS6110 based PCR in rapidly diagnosing smear negative pulmonary pulmoary tuberculosis in patients where tuberculosis was likely to be differential and rapid diagnosis was essential for optimal treatment.

Keyword

Bronchial washing; Amplicor PCR; IS6110 PCR

MeSH Terms

Bronchoscopy
Cough
Diagnosis*
Hemoptysis
Humans
Lung
Mycobacterium
Polymerase Chain Reaction*
Sensitivity and Specificity
Sputum
Tuberculosis
Tuberculosis, Pulmonary*