Yoko Murakami

Effect of Age on Relationship Between Exhaled Nitric Oxide and Airway Hyperresponsiveness in Asthmatic Children

BACKGROUND Numerous studies have examined the relationship between the fractional concentration of exhaled nitric oxide (Feno) and airway hyperresponsiveness (AHR). Our objective was to determine the effects of age on the relationship between Feno and AHR in asthmatic children. METHODS AHR was examined in 267 asthmatic patients (age range, 5 to 20 years). A challenge test was performed using acetylcholine chloride (Ach). We determined the provocative concentration of Ach producing a 20% decrease in FEV(1) from baseline (PC(20)). Feno was examined using the recommended online method before the Ach challenge test. RESULTS In children < 12 years of age (range, 5 to 11 years), decreasing AHR (PC(20)) was significantly related to higher Feno (r = -0.43; beta = -0.28; p < 0.001). In adolescents >or= 12 years of age (range, 12 to 20 years), decreasing PC(20) was associated with peripheral airway obstruction (FEV(1): r = 0.32; beta = 5.5; p = 0.002; forced expiratory flow at 50% of the FVC: r = 0.24; beta=8.4; p = 0.006; and forced expiratory flow at 25% of FVC: r = 0.28; beta=11.4; p = 0.002). AHR and Feno were weakly related (r = -0.18; beta = -0.14; p = 0.02). CONCLUSIONS In children with asthma, AHR is associated with airway inflammation. AHR in children with asthma may consist of variable components mainly reflecting airway inflammation. In contrast, in adolescents with asthma, AHR is associated with airway structural changes and weakly with airway inflammation. AHR in adolescents with asthma may consist of chronic components mainly reflecting airway remodeling.

Lung Sound Analysis in a Patient with Vocal Cord Dysfunction and Bronchial Asthma

Objective. Vocal cord dysfunction (VCD) is a condition characterized by adduction of the vocal cords, resulting in narrowing or even closure of the glottis during inspiration. This can cause wheezing that originates at the site of narrowing. Some patients have both VCD and asthma. In such cases, an acute episode of VCD can be difficult to differentiate from that of asthma. We tested the usefulness of lung sound analysis (LSA) in such a condition. Methods. We performed an LSA in a patient with asthma and coexisting VCD diagnosed using laryngoscopy. Results and conclusion. The LSA during an acute VCD episode revealed monophonic continuous adventitious sounds that were distributed symmetrically over both lung fields. The time domain analysis revealed that the adventitious sounds originated in the neck. These LSA findings clearly indicated that the acute episode was not due to asthma but due to VCD. This case illustrates that the LSA may be a useful tool to differentiate between an acute episode of asthma and that of VCD.

Aspirin is an Enhancing Factor for Food-dependent Exercise-induced Anaphylaxis in Children

Food-dependent exercise-induced anaphylaxis (FDEIA) is typified by the onset of anaphylaxis during or soon after exercise preceded by the ingestion of a causal food. In Japan, a questionnaire-based prevalence study of 76,247 junior high-school students revealed an FDEIA prevalence of 0.017%. 1 Physical activity is beneficial for children, with positive outcomes pertaining to both mental and physical well-being. This article is protected by copyright. All rights reserved.

Impact of omalizumab on medical cost of childhood asthma in Japan

Omalizumab is effective in children with severe asthma, but its impact on medical cost in Japan is not clear. We evaluated the impact of omalizumab on medical cost by comparing the pre‐ vs post‐omalizumab‐initiation medical costs of 12 children with severe asthma who received omalizumab for 2 years, and calculating incremental cost‐effectiveness ratio for omalizumab therapy. Health outcome was measured as hospital‐free days (HFD). The median total medical costs and medication fee per patient increased significantly after omalizumab initiation because of the high cost of omalizumab. The median hospitalization fee per patient, however, decreased significantly after omalizumab initiation due to reduction in hospitalization. Omalizumab led to an estimated increase of 40.8 HFD per omalizumab responder patient per 2 years. The cost was JPY 20 868 per additional HFD. Omalizumab can therefore reduce hospitalization cost in children with severe asthma in Japan.

Pale nasal mucosa affects airflow limitations in upper and lower airways in asthmatic children.

Background Severe asthmatics are thought to have severer rhinitis than mild asthmatics. A pale nasal mucosa is a typical clinical finding in subjects with severe allergic rhinitis. Objective The aim of this study was to investigate whether a pale nasal mucosa affects airflow limitations in the upper and lower airways in asthmatic children. Methods Rhinomanometry, nasal scraping, and spirometry were performed in 54 asthmatic children (median age, 10 years). The nasal mucosa was evaluated by an otolaryngologist. Thirty-seven patients were treated with inhaled corticosteroids, and 11 patients were treated with intranasal corticosteroids. Results Subjects with a pale nasal mucosa (n = 23) exhibited a lower nasal airflow (p < 0.05) and a larger number of nasal eosinophils (p < 0.05) in the upper airway as well as lower pulmonary functional parameters (p < 0.05 for all comparisons), i.e., the forced vital capacity (FVC), the forced expiratory volume in 1 second, and the peak expiratory flow, compared with the subjects who exhibited a normal or pinkish mucosa (n = 31). No significant difference in the forced expiratory flow between 25%–75% of the FVC, regarded as indicating the peripheral airway, was observed between the 2 groups. Conclusion A pale nasal mucosa may be a predictor of eosinophil infiltration of the nasal mucosa and central airway limitations in asthmatic children. When allergists observe a pale nasal mucosa in asthmatic children, they should consider the possibility of airflow limitations in not only the upper airway, but also the lower airway.

Exercise-Induced Wheezing among Japanese Pre-School Children and Pupils

BACKGROUND Exercise-induced wheezing (EIW) may be a symptom of asthma and is a predictor of exercise-induced bronchoconstriction, transient narrowing of the lower airway following exercise in the presence or absence of diagnosed asthma. Population-based studies with a large sample of EIW in relation to age, sex, current asthma severity and medication usage have been sparse. METHODS International Study of Asthma and Allergies in Childhood questionnaires were distributed at 885 nurseries, 535 primary schools, 321 junior high schools and 190 high schools, respectively, across Japan, and the corresponding data on 46,597, 41,216, 45,960 and 51,104 children were analyzed. RESULTS Prevalence of EIW was 4.8, 4.7, 17.9 and 15.4% for each of the four educational facility types, respectively. Among 24,103 current asthmatics, 20.9, 28.7, 76.1 and 73.6% of subjects for the 4 educational facility groups reported to have experienced EIW, respectively. Severity of current asthma was associated with the risk of EIW; odds ratio (95% confidence interval) of children with asthma attack every day for having EIW once a week or more, using intermittent asthmatics as reference group, were 24.48 (19.33 to 31.01) adjusted for other covariates. Among current asthmatic kindergartners, increase in risk for EIW due to ascending severity of current asthma was mitigated by daily use of leukotriene receptor antagonist (p for interaction = 0.071). CONCLUSIONS EIW was not rare among current asthmatic children. An increased risk for EIW was in accordance with increasing severity of current asthma and this relation was mitigated with leukotriene receptor antagonist daily use among kindergartners.