The Abbreviated Methacholine Challenge Test is Safe for Children

• Published in: The Journal of pediatrics 2025-01, Vol.276, p.114250, Article 114250
• Main Authors: Hevroni, Avigdor, Nemet, Shay, Ringel, Amit, Boursheh, Laurice, Handler, Nitay Alter, Bar-Yishay, Ephraim
• Format: Article
• Language: English
• Subjects: abbreviated MCT protocol; Adolescent; Asthma - diagnosis; bronchial hyperresponsiveness; Bronchial Provocation Tests - methods; Bronchoconstrictor Agents - administration & dosage; Child; Female; Forced Expiratory Volume; forced expiratory volume at 1 second (FEV1); Humans; Male; methacholine challenge test (MCT); Methacholine Chloride - administration & dosage; Prospective Studies
• ISSN: 0022-3476; 1097-6833; 1097-6833
• DOI: 10.1016/j.jpeds.2024.114250

To evaluate the safety of an abbreviated methacholine challenge test (MCT) protocol in children. This prospective, observational study enrolled children aged 6 through 18 years referred for the MCT. The abbreviated protocol was initiated with a methacholine dose of 0.03 mg/ml and escalated in fourfold increments, unless the forced expiratory volume at 1 second decline exceeded 10%, at which point the next dose was only doubled. The safety of this abbreviated approach was assessed by monitoring adverse events, and specifically, decreases in forced expiratory volume at 1 second over 40%, hypoxemia, or uncontrollable cough. The number of methacholine doses and test duration were recorded and compared with estimated outcomes derived from the full-length MCT protocol. One hundred twelve participants, aged 13.7 years (±3.3), successfully completed the protocol. Fifty-seven (51%) presented a positive MCT response. No significant clinical adverse events were observed. Of all participants, 2.7% exhibited an exaggerated response, in line with previously reported findings for the full-length protocol. The abbreviated approach resulted in an estimated average time-savings of 18:19 minutes per participant, thus reducing test length by 22:47 minutes for a negative MCT and by 14:34 minutes for a positive outcome. This abbreviated MCT protocol is safe for children and effectively shortens the duration of the MCT.