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

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.

Comparison of Treadmill and Cycle Ergometer in Male Korean College Students / 결핵

BACKGROUND: Generally VO2 max is higher in treadmill exercise than cycle ergometer exercise. According to Hassen and Wasserman, VO2 max with treadmill exercise is higher at ratio of 1.11 than that with cycle ergometer. VO2 max also is influenced by race, sociocultural background, exercise habit. In this study, VO2 max and AT were evaluated between Treadmill and cycle exercise in male Korean college students. METHOD: Study subjects were 44 male college students. We randomized them into 2 groups; 24 students did treadmill exercise at first and 1 week later did cycle ergometer. Another 20 students did in opposite method. They made symptom limited maximal exercise. Author defined maximal exercise as followings: 1) respiratory exchange ratio(RER)>1.1, 2) plateau>30 sec, 3) heart rate reserve(HRR)<15 %, or 4) breathing reserve(BR)<30 %. Otherwise their results are excluded as submaximal exercise. Anaerobic threshold(AT) was estimated by V-slope method. RESULTS: VO2 max and AT was 45.1 +/-6.66 ml/kg/min and 26.0 +/- 6.78 ml/kg/min in treadmill and 34.9 +/- 5.89 ml/kg/min, 19.5 +/- 4.77 ml/kg/min in Cycle Ergometer. The measured-VO2max/pred-VO2max was 98.8 +/- 13.24 % in treadmill; 84.4 +/- 13.42 % in cycle ergometer. Comparing VO2 max in treadmill with that obtained by Hassen's method, there were significant differences.(p<0.01). At maximal exercise HRR, O2/pulse, BR, VE/MVV, VE/VCO2 were higher in treadmill than in cycle but VE/VO2, Vd/Vt, Ti/Ttot were not. At AT O2/pulse, BR, VE/MVV, Ti/Ttot, were higher in treadmill than in cycle, otherwise not. CONCLUSION: According to the result of this study, there are larger gap between treadmill and cycle ergometer in normal Korean adults than foreign data, and it needs further study to obtain reference value of Korea.