Background The 4.5% hypertonic saline (HS) challenge test hasseveral benefits compared to histamine challenge test as gold stan-dard. Saline is an inexpensive non-pharmacological substancewhich is relatively safe. Its mechanism in inducing bronchospasmresembles that of asthma. Moreover, it can easily be made in amodest medical laboratory.Objective To determine the ability of 4.5% HS challenge test com-pared to histamine challenge test in diagnosing asthma in childrenwith chronic recurrent cough (CRC).Methods This study was a diagnostic test on children with CRCaged 6 to 14 years, conducted in outpatient clinic of Department ofChild Health, Cipto Mangunkusumo Hospital, Jakarta. All subjectsunderwent lung function tests. Subjects whose FEV 1 was <80% werediagnosed as asthmatic and underwent the 4.5% HS challenge testonly. Those whose FEV 1 was 80% underwent the histamine chal-lenge test followed by the 4.5% HS challenge test one or two weekslater. Test results were expressed as positive or negative. Based onthe results, we calculated the sensitivity, specificity, predictive val-ues, and likelihood ratios of the 4.5% HS challenge test.Results Forty-five subjects, consisting of 22 boys and 23 girls,were enrolled. The average age of subjects was 9 years old. Atopichistory in the family or in subjects themselves was found in 80% ofsubjects. Eight subjects had FEV 1 of <80%. Forty-four subjectswere diagnosed with asthma based on a baseline FEV 1 of <80%or a positive histamine provocation test. Thirty-seven subjects hada positive 4.5% HS challenge test; all had asthma. Sensitivity andspecificity of the 4.5% HS challenge test were 84.1% and 100.0%,respectively; the positive and negative predictive values were100.0% and 12.5%, respectively. The positive likelihood ratio wasinfinite and negative likelihood ratio was 0.16.Conclusion The 4.5% hypertonic saline challenge test can be usedas an alternative bronchial provocation test in diagnosing asthma inchildren with CRC. Further study with larger sample size is neededfor widespread usage.
Laryngeal Mucosal Reaction during Bronchial Histamine Challenge Test Visualized by Videolaryngostroboscopy
