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Published on: August 7, 2017
[Non specific bronchial hyperreactivity in infants]
L M Guirau1, D Solé, C K Naspitz
1Universidade Federal de São Paulo, Escola Paulista de Medicina.
Insights
The methacholine bronchoprovocation test effectively detects bronchial hyperreactivity in wheezing infants. This safe and well-tolerated test helps diagnose respiratory issues in young children.
Area of Science:
- Pediatric Pulmonology
- Respiratory Medicine
- Clinical Allergy
Context:
- Wheezing infants often present diagnostic challenges.
- Bronchial hyperreactivity (BHR) is a key feature in pediatric respiratory conditions.
- Early identification of BHR is crucial for timely intervention.
Purpose:
- To assess BHR in wheezing infants (WB) versus normal control infants (C).
- To evaluate the efficacy and safety of the methacholine bronchoprovocation test (BPT) in infants.
- To determine the provocative concentration of methacholine causing wheezing (PCW) in both groups.
Summary:
- The study utilized BPT with methacholine (M) on 51 WB and 20 C under two years old.
- Pulmonary auscultation monitored for wheezing to determine PCW.
- WB showed significantly lower PCW values (2.3 mg/ml) compared to controls (9.2 mg/ml), with 41% of WB responding positively at 2.5 mg/ml.
Impact:
- BPT using PCW is a viable method for diagnosing BHR in young children.
- The test is well-tolerated, safe, and easy to administer.
- Further research can elucidate the clinical significance of PCW values.
Objective:
To evaluate the presence of bronchial hyperreactivity (BHR) in Wheezing Babies (WB) and Normal Control Infants (C) employing the methacholine (M) bronchoprovocation test (BPT).
Methods:
Fifty-one WB and 20 C, all under two years old and assisted at the Department of Pediatrics of UNIFESP-EPM, were submitted to BPT with M, having pulmonary auscultation as monitoring parameter to evaluate PCW (provocative concentration of M causing wheezing). For all tests, M diluted in saline at increasing concentrations of: 0.025, 0.125, 0.25, 0.5, 1.0, 2.5, 5.0, and 10.0 mg/ml was delivered with O2 (5 l/min) by a face mask. It was inhaled through the mouth and nose during 2 minutes of quiet tidal breathing via nebulizer with 2 ml of solution.
Results:
None collateral effects were observed, except for tachypnea and tachycardia. There was statistically significant differences between WB (2.3 mg/ml) PCW value and C (9.2 mg/ml) (p < 0.05). At the PCW value of 2.5 mg/ml, 41% of the WB had statistically positive response (p < 0.05). This was not observed in the group C, when a positive response only occurred at the concentration of 5 mg/ml (25%). At this concentration we observed a clear cut difference between WB and C (p< 0.05). According to the severity, the highest M concentration was observed within the group displaying mild symptoms.
Conclusions:
We conclude that BPT utilizing PCW may be a good option for detecting BHR in young children. It is well tolerated by children, easy and safe to perform. Follow-up studies may clarify the real mean of the PCW.
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