Bronchial Hyperresponsiveness In Children Research Articles

Comment on the article “Use of methacoline challenge test to detect bronchial hyperresponsiveness”

Dear Editor;
 We read with interest the article titled “Use of methacoline challenge test to detect bronchial hyperresponsiveness in children with persistent rhinitis” published in Cukurova Medical Journal by Guc et al. [1]. 
 This study showed that BHR positivity is high in children with allergic rhinitis. Allergic rhinitis can cause false positive BHR. In addition, smoking and COPD can cause false positives [2, 3]. COPD can occur in childhood [4]. We think that it would be appropriate to mention this in the discussion part of this study.

Use of methacoline challenge test to detect bronchial hyperresponsiveness in children with persistent rhinitis

Purpose: The incidence of persistent rhinitis in childhood is increasing day by day. Since bronchial hyperreactivity (BHR) and asthma can also be seen in a significant proportion of patients with persistent rhinitis, the use of markers that may indicate the risk of developing asthma in these patients is very important in clinical follow-up. In this study, it was aimed to demonstrate the relationship between persistent rhinitis and asthma in childhood using the bronchial methacoline challenge test (BMCT) and to investigate other factors associated with the risk of developing asthma in patients with persistent rhinitis.
 Materials and Methods: Patients aged 6-18 years who presented with findings of persistent rhinitis were evaluated with a detailed history, physical examination, and spirometry. Patients with normal examination findings and spirometry findings, and patients whose examination findings and nasal inflammation findings were compatible with moderate-to-severe rhinitis were included in the study, and their atopy status was evaluated by skin prick test, and their BHR was evaluated by BMCT.
 Results: Seventy-three patients were included in the study. The mean age was 9±2.7years, 45.2% of the patients were male. 63% of the patients were allergic and family history of allergy was present in 45.2% of the patients. 82.2% of the patients had BHR detected with BMCT. The median blood eosinophil count (BEC) was 320/mm3 and the IgE level was 160kU/L. Patients with atopy had statistically significantly higher IgE and BEC values compared with non-allergic patients. Patients with BHR were found to be younger, and had higher median BEC values. In multivariant analysis, it was observed that the patient's age300/mm3, and IgE levels>250IU/L increased the probability of detecting BHR with BMCT. 
 Conclusion: Care should be taken for every patient with persistent rhinitis because of the risk of BHR and asthma. Atopy examinations should be performed, but the possibility of developing BHR and asthma should not be overlooked even in the patients who are non- allergic.

CATALASE CRS-262T GENE POLYMORPHISM AND CHANGES IN VENTILATION LUNG CAPACITY IN CHILDREN-RESIDENTS OF RADIOACTIVELY CONTAMINATED TERRITORIES.

to determine the association of catalase С-262Т gene polymorphism with the presence of bronchial hyper-reactivity in children living in radioactively contaminated territories. There were examined school-age children-residents of radioactively contaminated territories (RCT), who did not have clinical signs of respiratory pathology. Catalase (CAT) С-262Т gene deletion polymorphism was studied in the molecular genetic laboratory of the State Institution «Reference Center for Molecular Diagnostic of Public Health Ministry of Ukraine». Determination of the polymorphic variant by the catalase С-262Т gene was performed by Polymerase Chain Reaction (PCR) using specific oligonucleotide primers, followed by Restriction Fragment Length Polymorphism (RFLP) analysis. The CAT С-262Т gene polymorphism in children living in RCT was compared with that in the reference group of practically healthy individuals. Ventilation lung capacity was performed by computer spirometry according to the analysis of the loop «the flow-volume». A pharmacological inhalation test with a bronchodilator that acts on β2-adrenergic receptors of the lungs was used to detect early changes in the ventilatory capacity of the lungs - bronchial hyperreactivity. Comparative analysis showed that in the presence of bronchial hyperreactivity in children living in RCT, the CT genotype was more common than in children without bronchial hyperreactivity, and the frequency of the CC genotype was correspondingly reduced. There was a trend towards a decrease in the frequency of the TT genotype. An analysis of the frequency distribution of allelic variants of the CAT С-262Т gene polymorphism in children living in the RCT revealed a tendency to increase in the frequency of the T-allele and according to the decrease in the frequency of C-allele in the presence of bronchial hyperreactivity.Сonclusions. Thus, among children living in RCT, CT-homozygotes of CAT С-262Т gene polymorphism had bronchial hyperreactivity probably more often than CC-heterozygotes. In the presence of bronchial hyperreactivity, there was a trend towards an increase in the frequency of the T-allele and, accordingly, a decrease in the frequency of the C-allele.

Helminth infections and allergic diseases: Systematic review and meta-analysis of the global literature

There is considerable research interest in the role of helminth infections in the development of allergic diseases. However, findings from previous studies are mixed. Existing systematic reviews of these studies are outdated. We performed a systematic review of the global literature on the association between helminth infections and development and clinical outcomes of allergic diseases. We searched Cochrane Library, MEDLINE, EMBASE, ISI Web of Science, PubMed, Global Index Medicus, Scielo, KoreaMed, Google Scholar, and Lilacs for studies published up to January 2020. We included observational epidemiological studies (cohort, case-control, and cross-sectional studies) of children and adults reporting associations between helminth infections and asthma, allergic rhinitis, eczema, and atopy. We performed random-effects meta-analysis to summarize the effect estimates. We included 80 studies with 99,967 participants. In the meta-analyses, we did not observe an overall association between helminth infections and allergic diseases. There was, however, evidence that Ascaris lumbricoides infections were associated with an increased risk of bronchial hyperreactivity inchildren (risk ratio, 1.41; 95% CI, 1.17-1.70; I2= 50; P for I2= .09), and were associated with an increased risk of atopy among helminth-infected adults (risk ratio, 1.37; 95% CI, 1.18-1.61; I2= 52; P for I2= .02). We found no study that addressed the association between helminth infection and clinical outcomes of allergic diseases. The overall strength of the underlying evidence was low to moderate. Helminth infections may increase the risk of bronchial hyperreactivity in children and atopy in adults. Well-designed longitudinal cohorts may help clarify potential causal associations between chronic helminth infections and allergic diseases.

Allergic sensitisation did not affect bronchial hyper-responsiveness in children without respiratory tract symptoms.

The potential for immunotherapy to prevent asthma development has become a hot topic. This prompted us to revisit data from an early study that examined allergic sensitisation on bronchial hyperresponsiveness (BHR) in children with and without respiratory symptoms. Unlike previous studies, it used both indirect and direct test methods. The study was conducted in Kuopio, Finland, in 1994 and 247 children (55.1% boys) with a mean age 10.5±1.7years were recruited using a school survey: 165 with lower respiratory symptoms and 82 healthy controls. Each child underwent a 6-min free-running test and a methacholine test with a cumulative dose of 4900µg. All participants underwent skin-prick tests: 127were sensitised and 120 were non-sensitised. There were no significant differences in lung function between the sensitised and non-sensitised children. However, sensitisation was associated with BHR which was measured by both the methacholine test (2400µg versus >4900µg, p<0.001) and the free-running test (-3.5% versus -2.6%, p=0.042). No such differences were observed among the healthy controls. Sensitisation was a predictor of allergic diseases, and only multisensitisation to a minimum of four allergens increased the incidence of asthma. Allergic sensitisation did not affect BHR in children without respiratory symptoms.

Early life growth and associations with lung function and bronchial hyperresponsiveness at 11-years of age

Low birthweight and being born small-for-gestational age (SGA) are linked to asthma and impaired lung function. Particularly, poor intrauterine growth followed by rapid catch-up growth during childhood may predispose for respiratory disease. Bronchial hyperresponsiveness (BHR) is an essential feature of asthma, but how foetal and early childhood growth are associated with BHR is less studied. Our hypothesis was that children born SGA or with accelerated early life growth have increased BHR and altered lung function at 11-years of age.We studied the associations between SGA and early childhood growth with lung function and BHR at 11-years of age in a subgroup of 468 children from the Norwegian Mother, Father and Child Cohort Study (MoBa), and included data from the Medical Birth Registry of Norway (MBRN).Weight at 6 months of age was positively associated with forced vital capacity (adjusted Beta: 0.121; 95% Confidence interval: 0.023, 0.219) and negatively associated with the ratio of forced expiratory flow in first second/forced vital capacity (−0.204; −0.317, −0.091) at 11-years of age. Similar patterns were found for weight at 36 months and for change in weight from birth to 6 months of age. SGA or other various variables of early childhood growth were not associated with BHR at 11-years of age.Early life growth was associated with an obstructive lung function pattern, but not with BHR in 11-year old children. Foetal growth restriction or weight gain during early childhood do not seem to be important risk factors for subsequent BHR in children.

Current Asthma Prevalence Using Methacholine Challenge Test in Korean Children from 2010 to 2014.

BackgroundMost epidemiological studies depend on the subjects' response to asthma symptom questionnaires. Questionnaire-based study for childhood asthma prevalence may overestimate the true prevalence. The aim of this study was to investigate the prevalence of “Current asthma” using the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire and methacholine challenge test in Korean children.MethodsOur survey on allergic disease included 4,791 children (age 7–12 years) from 2010 to 2014 in Korean elementary schools. Bronchial hyperresponsiveness (BHR) was defined as provocative concentration of methacholine causing a 20% fall in forced expiratory volume in one second (FEV1) (PC20) ≤ 16 mg/mL. “Current asthma symptoms” was defined as positive response to “Wheezing, current,” “Treatment, current,” or “Exercise, current.” “Current asthma” was defined when the subjects with “Current asthma symptoms” showed BHR on the methacholine challenge test or had less than 70% of predicted FEV1 value.ResultsThe prevalence of “Wheezing, ever,” “Wheezing, current,” “Diagnosis, ever,” “Treatment, current,” “Exercise, current,” and “Current asthma symptoms” was 19.6%, 6.9%, 10.0%, 3.3%, 3.5%, and 9.6%, respectively, in our cross-sectional study of Korean elementary school students. The prevalence of BHR in elementary school students was 14.5%. The prevalence of BHR in children with “Wheezing, ever,” “Wheezing, current,” “Diagnosis, ever,” “Treatment, current,” and “Exercise, current” was 22.3%, 30.5%, 22.4%, 28.8%, and 29.9%, respectively. BHR was 26.1% in those with “Current asthma symptoms.” The prevalence of “Current asthma” was 2.7%.ConclusionsOur large-scale study provides 2.7% prevalence of current asthma in Korean elementary school children. Since approximately one third of the children who have “Current asthma symptoms” present BHR, both subjective and objective methods are required to accurately predict asthma in subjects with asthma symptoms.

TNF-α (rs1800629) polymorphism modifies the effect of sensitization to house dust mite on asthma and bronchial hyperresponsiveness in children

Asthma is a complex disease, with various genetic and environmental factors implicated in its development. Sensitization to the house dust mite (HDM) is closely linked with the development of respiratory allergies, including asthma. However, some children sensitized to HDM do not complain of any symptoms of respiratory allergies, even though HDM is correlated with an increased risk for developing asthma, suggesting the involvement of other factors. Tumor necrosis factor (TNF)-α is associated with the pathophysiologies of asthma in combination with its genetic polymorphism. The aim of the present study was to elucidate the associations between sensitization to HDM, polymorphism of TNF-α rs1800629, and asthma/bronchial hyperresponsiveness (BHR). Our results revealed that sensitization to HDM is associated with asthma diagnosis in lifetime, current asthma, and BHR in Korean children. Furthermore, the genetic polymorphism of TNF-a rs1800629 was found to modify and interact with these associations. This study suggests that prevention strategies for childhood asthma need to be targeted according to genetic susceptibility.

House dust mite sensitization is associated with bronchial hyperresponsiveness in children with allergic rhinitis

House dust mite sensitization is associated with bronchial hyperresponsiveness in children with allergic rhinitis

MOLECULAR GENETIC ASPECTS OF BRONCHIAL HYPERREACTIVITY IN CHILDREN - RESIDENTS OF RADIOACTIVELY CONTAMINATED AREAS.

to determine the relationship between polymorphisms of glutathione S-transferase gene family andbronchial hyperreactivity in children living in radioactively contaminated areas. School age children-residents of radioactively contaminated areas (RCA), without clinicalsigns of respiratory pathology were examined. Molecular genetic studies were carried out by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) for further analysis. The GSTT1, GSTM1 gene deletion polymorphism was investigated using multiplex PCR. PCR and PCR-RFLP analyses were performed in the studyof the GSTP1 gene A313G polymorphism. The ventilation lung capacity was examined by the pneumotachographicmethod according to the analysis of «the flow-volume» loop. The pharmacologic inhalation test with bronchodilator drug, affecting the β2-adrenergic lung receptors was used to detect the early changes in the ventilation lungcapacity - the bronchial hyperreactivity (latent and nonlatent bronchospasm). Molecular genetic studies showed that the GSTM1 gene deletion genotype and the GSTP1 gene A313G polymorphism were found significantly more often in the subgroup of children with bronchial hyperreactivity living inRCA than in children without bronchial hyperreactivity and children of the control group. The frequency of GSTT1deletion polymorphism did not have a statistically significant difference in all subgroups. The GSTM1 gene deletion polymorphism and the GSTP1 gene A313G genotype may be a risk factor fordeveloping bronchial hyperreactivity in children living under adverse environmental conditions, including radioactively contaminated areas.

Peak expiratory flow rate assessment to screen for asthma in children with allergic rhinitis

Background: Allergic rhinitis is a common disease affecting around 10-25% of the population worldwide. There is a temporal relationship between the onset of allergic rhinitis and asthma and the ‘unified airway hypothesis’ explains this. Many researchers have demonstrated bronchial hyper-responsiveness prior to onset of asthma symptoms further validating this hypothesis. Further many studies favour treating allergic rhinitis may prevent the onset of asthma. So, detecting allergic rhinitis earlier and treating it adequately is of vital importance. The aims and objectives of this study is to identify bronchial hyper responsiveness in children with allergic rhinitis, prior to the onset of asthmatic symptoms, by measuring PEFR and its clinical correlates.Methods: A prospective observational study was conducted in Department of Paediatrics in Sree Balaji Medical College and Hospital. Inclusion and Exclusion Criteria were defined, and the study was conducted on a total of 85 children. After taking informed consent from parents, the children coming under the study population were analyzed for their baseline characteristics and PEFR is measured using a low reading Mini Wright peak flow meter and compared with mean value of south Indian children using the formula, PEFR= {(HEIGHT IN CM-100) X5} +100.Results: The mean PEFR as expressed in percentage of expected PEFR is 77.28% in males and 83.34% in females. The mean percentage of expressed PEFR does not vary significantly between different age groups. Of the 85 children,48(56.5%) have mild intermittent allergic rhinitis,28(32.9%) have mild persistent allergic rhinitis,5(5.9%) have moderate-severe intermittent allergic rhinitis and 4(4.7%) have moderate-severe persistent allergic rhinitis. There were 37(43.5%) blockers (with predominant nose block) and 48(56.5%) runners (with predominant rhinorrhea).Conclusions: PEFR is abnormal in 41.2% of children with allergic rhinitis. PEFR reduces linearly as the severity of allergic rhinitis increases. PEFR decreases as the number of cardinal symptoms increases. PEFR increases significantly after treatment of allergic rhinitis alone.

Serum Clara cell protein and atopic phenotype in children up to 2years of age.

Low value of serum Clara cell protein (CC16) is associated with bronchial hyperreactivity in children. To evaluate the serum CC16 in relation to atopy and previously manifested LRTD. In the population of 163 healthy 5- to 24-month-old children, atopy was determined by Phadiatop-infant (serum-specific IgE≥0.35kUA/L), serum CC16 by ELISA, while data on previously manifested low respiratory tract diseases (LRTD) were collected from the Health Care Center database. In atopic children, serum CC16 negatively correlated with age (r -.281, P=.041, n=53), while in nonatopic children, this correlation was positive (r .200, P=.036, n=110). Atopic ≥8-month-old children with previously manifested LRTD had lower level of CC16 (3.07ng/mL) in relation to atopic children without LRTD at the same age (6.51ng/mL), P=.029 (value of serum CC16≥4.8ng/mL indicates atopic phenotype without LRTD 75% sensitivity, 87.5% specificity). In 8- to 24-month-old children with previously manifested pneumonia, serum CC16 was lower in atopic (2.9ng/mL) in relation to nonatopic children (3.7ng/mL), P=.029 (serum CC16 ≤3.4ng/mL indicating atopy in the group of children with pneumonia, sensitivity 100%, and specificity 77%). Atopic 8- to 24-month-old children with previously manifested pneumonia had lower CC16 in relation to other atopic children in this age (P=.021) (for cutoff CC16≤3.4ng/mL sensitivity 100%, specificity 77%), and also often chronic wheezing (atopic with pneumonia 83.3%, n=5/6 vs atopic without pneumonia 21.4%, n=3/14), P=.018. Low serum CC16 is associated with previously expressed pneumonia and chronic wheezing in atopic children.

Механизмы формирования высокой кашлевой готовности у детей с рецидивирующим бронхитом

The process of recurrent bronchitis is accompanied by increased threshold sensitivity of the bronchi to inflammatory mediators, the occurrence of which affect brain activity with a predominance of irritation meso diencephalic structures, autonomic tone, manifesting hypersympathicotonia and increase the level of central regulation contour, cerebral hemodynamics, characterized by increased tone of arterioles and veins , peripheral vascular resistance and venous outflow obstruction. The emerging of bronchial hyperresponsiveness in children with recurrent bronchitis leads to bronchial obstruction at all levels of the bronchial tree, furthermore it leads to reduction of redundant lung capacity and is, apparently, one of the pathogenic mechanisms of persistent flow of inflammatory changes in the bronchi and increased cough readiness.

Association between menarche and increased bronchial hyper-responsiveness during puberty in female children and adolescents.

Bronchial hyper-responsiveness (BHR) is a key feature of asthma. The degree of BHR in children may be altered by several factors. We evaluated the prevalence of BHR according to age and gender in pediatric and adolescent population and analyzed the associated factors for gender differences. Among the 2,067 subjects, methacholine challenge tests were performed in 1,820 children from one elementary and one middle school in Seoul, Korea. A total of 1,725 subjects between 6 and 14 years old were included in the analysis. The prevalence of BHR, defined as a provocative concentration that induced a 20% reduction of FEV1 (PC20 ) that was less than 8 mg/ml, was evaluated according to age and gender. Gender differences associated with BHR prevalence at each age were calculated and multiple logistic regression analyses were performed to identify factors associated with BHR by gender. The prevalence of BHR (PC20 ≤ 8 mg/ml) for each gender decreased with age (P < 0.001). Although the prevalence of BHR linearly decreased in males with age, females showed an increase after 11 years of age. BHR in males was associated with a younger age (aOR, 0.797; 95%CI, 0.678-0.925), a higher blood eosinophil counts (%) (aOR, 1.160; 95%CI, 1.047-1.284), atopy (aOR, 2.091; 95%CI, 1.003-4.359), and a lower FEV1 /FVC ratio (aOR, 0.947; 95%CI, 0.901-0.995), and FEF25-75% (aOR, 0.980; 95%CI, 0.961-0.999). In females, BHR was significantly associated with a younger age (aOR, 0.845; 95%CI, 0.747-0.957), lower FEV1 (%) (aOR, 0.961; 95%CI, 0.938-0.984), and menarche (aOR, 3.674; 95%CI, 1.226-11.012). BHR declined with age in the Korean pediatric population. A younger age and reduced lung function were common factors related to BHR in both genders. Additionally, atopy was related to BHR in males, whereas sexual maturation was related to BHR in females. These findings have important clinical implications for evaluating of childhood BHR and asthma related to gender. Pediatr Pulmonol. 2016;51:1040-1047. © 2016 Wiley Periodicals, Inc.

Respiratory syncytial virus infection and bronchial hyperreactivity in children up to two years of age in correlation with atopy.

Bronchiolitis in early childhood caused by respiratory syncytial virus (RSV) is considered to be important risk factor of the recurrent wheezing and asthma development. The aim of this study was to examine the frequency of RSV infection and atopy in children up to two years of age and to determine their correlation with bronchial hyperreactivity. The study included 175 children aged 5-24 months. The presence of RSV infection was identified by serum levels of IgA and IgG determined by ELISA. Bronchial hyperreactivity (BHR) has been defined as the existence of chronic bronchial disease and/or three or more previous suspected diagnosis of acute bronchial disease. Atopy was confirmed by detection of the specific serum IgE using quantitative multitest Phadiatop infant (cut off 0.35 kUA/L). The children with atopy were more frequently infected with RSV (43.3%) than those without atopy (22.8%; p = 0.02). The higher frequency of RSV infection was found in children with BHR in comparison with those without it but only in the group who also had atopy (77.8% vs. 28.6%, p = 0.018). In the female children, BHR and RSV infection were associated in 62.5% of cases, regardless the atopy. In the male children with atopy, RSV infection was associated with BHR in 83.3% of the cases, while in those without atopy, RSV infection with BHR was found in only 17.4% of the cases. Children up to two years of age with atopy are more frequently infected with RSV (43.3%) than nonatopic children. Every third child with atopy develops BHR and 77.8% of them also have RSV infection. Atopic children are at higher risk for development of BHR when infected with RSV also.

Clinical value of fractional exhaled nitric oxide level in predicting bronchial hyperreactivity in asthmatic children

Objective To evaluate the clinical value of fractional exhaled nitric oxide (FeNO) level in asthmatic children to predict bronchial hyperresponsiveness by analyzing the correlation between fraction of exhaled nitric oxide and bronchial provocation test. Methods One hundred and fourteen asthma outpatients of Shengjing Hospital were enrolled, FeNO levels, spirometry and bronchial provocation test were measured. Results In the bronchial provocation test, there were 33 positive and 81 negative cases.The positive group had a significantly higher FeNO levels than the negative ones(19.0×10-9 vs.16.0×10-9, P=0.000). By the ROC curve, the best FeNO cut-off value to predict bronchial hyperresponsiveness was 38.5×10-9 with high specificity(92.6%) but relatively low sensitivity(36.4%). There was no relationship between methacholine provocative dose causing a 20% fall in FEV1(PD20-FEV1) and the level of FeNO. Conclusion FeNO level has important predicting value for bronchial hyperreactivity in children with asthma.The level of FeNO >38.5×10-9 has high predictive value in asthmatic children with bronchial hyperreactivity. Key words: Exhaled nitric oxide; Methacholine bronchial provocation test; Asthma; Children

Prevalence and association of asthma and allergic sensitization with dietary factors in schoolchildren: data from the french six cities study

BackgroundThe prevalence of asthma and allergy has recently risen among children. This increase in prevalence might be related to various factors, particularly diet. The aim of this study is to assess the prevalence and association of asthma and allergic sensitization with dietary factors in the French Six Cities Study.MethodsCross-sectional studies were performed among 7432 schoolchildren aged 9–11 years in Bordeaux, Clermont-Ferrand, Créteil, Marseille, Reims, and Strasbourg. Parental questionnaires, based on the International Study on Asthma and Allergies in Childhood (ISAAC), were used to collect information on allergic diseases and potential exposure factors including a food frequency questionnaire to evaluate dietary habits. Skin prick testing to common allergens for allergic sensitization and bronchial hyper-responsiveness (BHR) testing to exercise were performed. Confounders control was performed with multiple logistic regressions.ResultsAsthma symptoms, asthma and allergic sensitization were more prevalent in boys than in girls and were more prevalent in the South than in the North of France. After adjustment for confounders, fruit juice intake was associated with a low prevalence of lifetime asthma (ORa [95 % CI]; 0.73 [0.56–0.97]), butter intake was positively associated with atopic wheeze (1.48 [1.07–2.05]) and having lunch at the canteen 1–2 times/week compared to never or occasionally was associated with a lower prevalence of past year wheeze (0.71 [0.52–0.96]), lifetime asthma (0.76 [0.60–0.96]) and allergic sensitization (0.80 [0.67–0.95]). Meat intake was inversely related to past year wheeze among atopic children (0.68 [0.50–0.98]) while fast food consumption and butter intake were associated with an increase prevalence of asthma (2.39 [1.47–3.93] and 1.51 [1.17–2.00] respectively). Fish intake was associated with a lower prevalence of asthma among non-atopic children (0.61 [0.43–0.87]. None of the dietary factors was associated with BHR.ConclusionsDiet is associated with wheeze, asthma and allergic sensitization but not with BHR in children. These results provide further evidence that adherence to a healthy diet including fruits, meat and fish seems to have a protective effect on asthma and allergy in childhood. However, prospective and experimental studies are needed to provide causal evidence concerning the effect of diet on asthma and atopy.

Exercise-induced bronchospasm diagnosis in children. Utility of combined lung function tests

The diagnosis of exercise-induced asthma or bronchospasm (EIB) is a complex dare in daily clinical practice. The consensus is that if bronchial hyper-responsiveness (BHR) is demonstrated in a patient with symptoms consistent with EIB, then that patient can be diagnosed with exercise-induced bronchospasm. The aim of this study was to determine which BHR test is the most efficient to diagnose EIB. Children under 16, without previous asthma diagnosis, or with stable asthma, complaining of asthma-like symptoms triggered by exercise were included. Bronchodilator, methacholine, mannitol, and exercise tests were performed on all patients, following established protocols. The performance of single and combined tests was determined. Of 46 patients (median age: 12 yr, ranged 8-16 y.o.) were recruited, 30 (70%) previously diagnosed of asthma. BHR was detected in 93.47% of the children. The exercise challenge test detected BHR in 11 of 46 (23.90%) patients, bronchodilator test in 10 of 46 (21.70%), mannitol in 36 of 45 (80%) and methacholine in 41 of 45 (91.11%). The total number of patients with BHR was detected using a combination of the methacholine and mannitol tests. A combination of the methacholine test performed first, followed by the mannitol test, was able to diagnose BHR in 100% of children with lower number of tests (n = 45) than if the order was reversed (n = 50). Methacholine and mannitol tests detect BHR in most children with suspected EIB. Bronchodilator and exercise tests show a low positivity rate. A combination of the methacholine test, followed by the mannitol test, gives the highest return to identify BHR in children for the diagnosis of EIB.

Assessment of Bronchial Hyperrespinsiveness to Methacholine in Children with Atopic Dermatitis

The methacholine challenge test (MCT) is commonly used to assess a bronchial hyperresponsiveness (BHR). Many studies have shown the importance for BHR in children with bronchial asthma, but BHR in children with atopic dermatitis (AD) is poorly defined. The aim of this study is to identify the BHR in children with AD and investigate the correlation between the degree of BHR and the severity of AD.

Bronchial hyperreactivity in children with antibody deficiencies

BackgroundAntibody deficiency comprises a heterogeneous group of disorders characterised by the body's inability to mount an effective antibody response to pathogens. Although it has been reported that asthma and allergic disease are frequent in antibody deficiencies, there are no data that evaluate and compare bronchial hyperreactivity (BHR) in all groups of antibody deficiencies. In this study, we aimed to evaluate and compare the frequency of BHR in patients with different antibody deficiencies. MethodsThe study was carried out on 113 patients between ages 5 and 18 diagnosed with antibody deficiencies. The patients and their families were questioned on their history of asthma and allergic diseases. Allergic skin prick tests and non-specific bronchial provocation test with methacholine was done for all patients. Complete blood count and serum total IgE levels were measured. ResultsThe mean age of the patients was 10.8±3.8 years and 66.4% were male. Within the study group 41.6% of the patients had selective IgA deficiency, 24.8% had IgG subclass deficiency, 14.2% had partial IgA deficiency, 10.6% had common variable immunodeficiency, 6.2% had transient hypogammaglobulinaemia and 2.7% X-linked agammaglobulinaemia. In total group, 42.5% had bronchial hyperreactivity with methacholine challenge test. BHR was more significant in both patients with selective IgA deficiency and partial IgA deficiency compared to those with IgG subclass deficiency (P=0.041 and P=0.038, respectively). ConclusionBHR was high in antibody deficiencies, especially selective IgA deficiency compared to IgG subclass deficiency.