Comparison of 3 protocols in the methacholine bronchial provocation test

초록

Purpose: In Korea, KoKo dosimetry and Aerosol Provocation System (APS) are used in the methacholine provocation test (MBPT). In this study, three protocols of the MBPT were compared. Methods: In patients showing a positive MBPT using short 2-concentration methods for APS with cumulative provocative doses of methacholine which results in a 20% fall in forced expiratory volume in 1 second (FEV1) 1 ) (PD20) 20 ) <= 962.81, the MBPT was repeated, using 14-breaths methods for APS. In them, PD20 20 of those 2 protocols were compared to each other. Provocative concentration of methacholine which results in a 20% fall in FEV1 1 (PC20) 20 ) in 14-breaths methods was also compared with that of 5-breaths methods in other patients showing a positive MBPT with KoKo dosimettry during the study period. Results: The positive rate in short 2-concentration methods was 18.1% (43 of 238), while that in 5-breaths methods was 14.0% (6 of 43). They were not different from each other (P=0.342). In 7 patients who underwent the MBPT twice, using short 2-concentration and subsequent 14-breaths methods. The median of PD20 20 with a positive MBPT using short 2-concentration methods was 573.8 mu g with interquartile range (IQR) of 147.8-682.3 mu g, whereas that in repeated MBPT using 14-breaths methods was 526.4 mu g (IQR, 95.0- 907.1 mu g). They did not differ from each other (P=0.735). The median of PC20 20 in MBPT using 14-breaths methods was 4.76 mg/mL (IQR, 0.066-10.3 mg/mL) tended to be higher than that in other 6 patients who showed a positive MBPT using 5-breaths methods, 1.95 mg/mL (IQR, 0.42-4.85 mg/mL), but it was not significant (P=0.534). Conclusion: Bronchial hyperresponsiveness was not different in 3 protocols of MBPT. ( Allergy Asthma Respir Dis 2024;12:140-146) )

키워드