Leukotriene D4 Bronchial Provocation Test (LTD4-BPT) as an Indicator for the Use of Leukotriene Receptor Antagonist (LTRA)

Background: Therapeutic outcomes of leukotriene receptor antagonist (LTRA) vary in asthmatics，and there's not an ideal and simple way for prediction at present. Objective：To investigate whether leukotriene D4 bronchial provocation test (LTD4-BPT) could be an indicator of actual therapeutic outcome of LTRA. Methods：A single centre, open-labeled trial was performed in 32 asthmatics with positive LTD4-BPT result for a month. All subjects were categorized according to airway responsiveness to leukotriene D4（PD20FEV1-LTD4）. Subjects received montelukast therapy (10mg, once per night), and reassessment was performed (3\~5) days after withholding LTRA. The primary end-point was the difference in monthly PEFR. Secondary endpoints included the difference in FENO, PD20FEV1-LTD4, PD20FEV1-MCh, pre-test FEV1, ACT score, AQLQ symptom score, week 4 PEFmax and PEFmin as compared with week 1, gradual decrease in the use of salbutamol and the days without using salbutamol.