Alba Torrent Vernetta

Hiperrespuesta bronquial a la metacolina en niños menores de 4 años con bronquitis de repetición

OBJECTIVE To evaluate bronchial hyperresponsiveness in children under 4 years of age with recurrent wheezing bronchitis, and to determine if its presence or absence can predict the subsequent progression to a transient or persistent wheezing bronchitis phenotype. POPULATION AND METHODS A bronchial challenge test was performed with methacholine using a modified tidal volume method, without sedation in a group of patients from 8 to 47 months of age with recurrent wheezing bronchitis and a control group of healthy children. A decrease in oxygen saturation of ≥ 5% or an increase in respiration rate of >50% [PCwheeze (PCw)] was considered a positive response. The patients were subsequently clinically followed up to assess their progress. RESULTS A total of 63 patients and 16 controls were studied (mean age 23.9 vs. 25.2 months). The PCw was lower than the control group (≤ 4 mg/ml) in 43 (68%) children from the bronchitis group (P<0.001). No significant adverse effects were observed on performing the test. After a mean follow up of 28.5 months, completed in 49 of the patients, no differences were seen between the presence of bronchial hyperresponsiveness at the beginning of the study and the subsequent progression to transient, infrequent and frequent wheezing (P=0.63). CONCLUSIONS A high percentage of children under 4 years of age affected by wheezing bronchitis had a bronchial hyperresponse. The subsequent progression to transient or persistent wheezing bronchitis phenotype is not associated with bronchial hyperresponsiveness.

Bronchial Hyperresponsiveness to Methacholine in Children Under 4 Years with Recurrent Bronchitis

Objective To evaluate bronchial hyperresponsiveness in children under 4 years old with recurrent wheezing bronchitis, and to determine if its presence or absence can predict subsequent progression to a transient or persistent wheezing bronchitis phenotype.

Authors’ response to correspondence for EPI-STREP-064 publication

Dear Drs. Hare, Grimwood, and Chang, We sincerely thank you for your correspondence and appreciate you pointing out the unintended error in our publication’s citation. We agree with your response and feedback. To clarify the point that there is heterogeneity in the literature about the use of NPS to understand lower lung microbiota in disease, we have added the following references to our sentence: “Several studies assessed a possible correlation between BALF and nasopharyngeal swab (NPS) specimens in terms of chronic LRTI etiology, with inconsistent results [1–5].”