Bronchial hyper-responsiveness predicts the development of mild clinical asthma within 2 yr in school children with hay-fever

In children with mild asthma, symptoms are not always apparent. Therefore, results of tests play an important role for the diagnosis. First, to investigate whether children with bronchial hyper-responsiveness (BHR) but no symptoms of asthma in 1992 had developed clinical asthma at follow up in 1994. The second aim was to find out the diagnostic properties of tests for asthma/allergic inflammation, using either doctor diagnosed asthma (DDA), self-assessed symptoms of asthma or iso-capnic hyperventilation of cold air (IHCA), as the standard, to diagnose asthma in a group of children with hay fever. Twenty-eight children with pollinosis, 12 of them with a history of asthma for the first time during the season 1992, were studied during the birch pollen season and in the autumn of 1994. During both periods, the bronchial hyper-reactivity was estimated by methacholine bronchial provocation tests (MBPT), bronchial variability by peak expiratory flow rate variability, subjective symptoms of asthma by visual analogue scale (VAS) and bronchial inflammation by serum and urine levels of inflammatory mediators. In 1994 IHCA was added during both seasons. Eight of 16 children with BHR but without clinical asthma in 1992 had developed asthma in 1994, 14 of 16 reacted to IHCA and 13 to MBPT. All 12 children with DDA in 1992 had still asthma in 1994 and 14 children with BHR in 1992 had persistent BHR in 1994. Of 23 children with BHR in 1992, 17 had DDA in 1994 and all maintained their BHR. Furthermore, 20 of them reacted to IHCA in 1994. In 1994, 24 of 28 hay-fever children had a positive IHCA tests and 24 had positive MBPT. In relation to VAS, the sensitivity of IHCA and MBPT to predict present asthma was high, but the specificity low, whereas the specificity of most other tests was high, but based on few individuals. In relation to DDA both the IHCA test (65-80%) and the MBPT test (79-85%) had a high sensitivity and it was three to six times more likely to find a positive test among asthmatics than in non-asthmatics. Children with hay fever without clinical asthma have a high risk of developing asthma within 2 yr. In relation to DDA, inhalation of cold air and the MBPT showed a high sensitivity.     

Association of serum-soluble CD26 and CD30 levels with asthma, lung function and bronchial hyper-responsiveness at school age

Aim: There is a need for markers of Th1 and Th2 imbalance in diseases such as asthma. CD30 is an activation marker of Th2 cells, and importance of Th1 marker CD26 was recently found in adult asthma. We studied whether serum‐soluble CD30 (sCD30) or serum‐soluble CD26 (sCD26) could support early diagnosis of asthma in children at school age. Methods: sCD26 and sCD30 were measured in 34 children with clinically confirmed asthma, 31 with possible asthma and in 147 controls. In addition, the associations of flow volume spirometry, methacholine inhalation challenge and free running test results with serum sCD26 or sCD30 were analysed. Results: Serum sCD30 was significantly higher in children with confirmed asthma (mean 91.5 IU/mL, SD 23.0) than in the controls (78.8 IU/mL, 25.9; p = 0.042). No significant differences were found in serum sCD26 levels between the groups. There was a negative correlation of mean mid expiratory flow values with serum sCD26 (r = ?0.22, p = 0.0018). Neither methacholine inhalation challenge nor free running test results were associated with serum sCD26 or sCD30. Conclusion: Serum sCD30 was higher in children with asthma. However, marked overlap in serum sCD30 between asthmatic and healthy children limits the usefulness of sCD30 as a diagnostic marker of asthma.     

Ratio of eosinophil cationic protein/eosinophil count as a new marker in children with acute asthma

BACKGROUND: It is a matter of concern whether serum eosinophil cationic protein (ECP) can be considered as a disease marker in children with acute asthma being treated without corticosteroids. METHODS: Fourteen children (nine male, five female, aged 6-12 years) with acute asthmatic exacerbation, administered the appropriate drugs, with the exception of systemic or inhaled corticosteroids, were examined. They were all free from apparent asthmatic attacks during a follow-up period of 1 month. Serum ECP, eosinophil count and forced expiratory volume in 1 s (FEV1) were measured at referral, on the day of discharge, 1 week and 4 weeks after discharge, respectively. RESULTS: The ratio of ECP/eosinophil count (ECP:Eo ratio), expressed as micrograms of ECP (microgram/L)/the number of eosinophil (/microL) x 1000, was also evaluated as a marker of eosinophil activation. Compared with the value at referral, FEV1 (% predicted) significantly increased on the day of discharge (P < 0.05), 1 week after (P < 0.05) and 4 weeks after discharge (P < 0.05). However, serum ECP concentrations showed no significant changes during the follow-up period. Eosinophil count showed no significant changes on the day of discharge or 1 week after discharge, but significantly increased 4 weeks after discharge (P < 0.05). In contrast, the ECP:Eo ratio significantly decreased on the day of discharge (P < 0.05), 1 week after (P < 0.05) and 4 weeks after discharge (P < 0.05). CONCLUSION: These data suggest that serum ECP is a poor disease marker in asthmatic children with acute exacerbation who receive no corticosteroid therapy, probably due to marked changes in the eosinophil count. However, the ECP:Eo ratio might be a better marker than serum ECP in such patients.     

Prevalence of asthma and bronchial hyperreactivity in Danish schoolchildren: no change over 10 years

Aim: To describe the point prevalence of current physician‐diagnosed asthma and bronchial hyperreactivity (BHR) in 2001 among unselected Danish schoolchildren aged 6–17 years, compared with the prevalence from a similar study from 1990 to 1991. Methods: Cross‐sectional study using parental questionnaire on asthma and respiratory symptoms combined with a 6‐min free running test with peak expiratory flow rate (PEFR) measurement (n = 1051, response rate 89.3%). Results were compared with those of a similar study in the same area from 1990 to 1991. Main outcome measures were current physician‐diagnosed asthma or BHR in children without physician‐diagnosed asthma measured by either a decrease in lung function after standardized running test and/or variability in PEFR on home monitoring. Results: The prevalence of current physician‐diagnosed asthma was 4.0% [95% confidence interval (CI) 2.7–5.3%] in 1990–1991 and 3.6% (95% CI 2.4–4.8%) in 2001. The prevalence of BHR was 3.2% (95% CI 2.0–4.4%) in 1990–1991 and 2.0% (95% CI 1.1–2.9%) in 2001. The combined prevalence was 7.2% (95% CI 5.4–8.9%) in 1990–1991 and 5.6% (95% CI 4.2–7.1%) in 2001. Conclusion: The point prevalence of current physician‐diagnosed asthma and BHR among unselected Danish schoolchildren aged 6–17 years was unchanged over 10 years between 1990–1991 and 2001.     

Eosinophil granule proteins in the assessment of airway inflammation in pediatric bronchial asthma

Eosinophil granule proteins such as eosinophil cationic protein (ECP), eosinophil peroxidase (EPO) and eosinophil protein X (EPX) in serum and urine are indirect measures of eosinophil activity. The measures have been evaluated for prediction, diagnosis and monitoring of anti-inflammatory treatment modalities in children with asthma. Assessments in serum and urine are highly dependent on sampling procedures and must be performed under strictly controlled conditions using standardized sampling and laboratory procedures. The measures are influenced by circadian and seasonal variations. Measurement of the eosinophil granule proteins does not improve the predictive value of a family history of atopy. Due to insufficient sensitivity and specificity, the measures are not useful in the diagnosis of asthma in children, and the clinical use of eosinophil proteins in the individual child for assessment of asthma severity has not been sufficiently validated. Serum and urine eosinophil granule proteins, however, may be useful in extending our knowledge of suppressive effects on eosinophil activity of various doses, devices and administration regimens of inhaled glucocorticoids in children. Such evaluations may be performed in randomized, double-blind trials of well-defined age groups and they should include measures of compliance. One important aspect to look at would be the distinction between suppressive effects on eosinophil activity and clinically important anti-inflammatory effects. Considering the complexity of airway inflammation and the heterogeneity of childhood asthma, however, it may be too simplistic to look for a single measure of the inflammatory processes. In the future, perhaps, a combination of products of inflammatory cells may give more clinically relevant information with respect to prediction, diagnosis, monitoring and outcome of childhood asthma.     

Markers of inflammation and bronchial reactivity in children with asthma, exposed to animal dander in school dust

Several studies have confirmed the presence of animal dander allergens in school dust but the effect of this indirect animal exposure on health has not been evaluated. In this study we investigated bronchial reactivity and markers of eosinophil activity and inflammation during two separate weeks of school in 10 children with mild asthma and a positive skin prick test to cat and dog. At the beginning and the end of the first week the children underwent bronchial challenges with methacholine, and at the beginning and the end of the second week they underwent nasal lavages (NAL) and induced sputum samplings. Blood and urine samples for analysis of inflammatory markers were obtained before and after both school weeks. Peak expiratory flow (PEF) and symptoms of asthma and allergy were recorded daily, and spirometry was performed on each visit. The exposure to animal dander allergens was estimated from dust samples obtained in the subjects' schools and homes. Bronchial sensitivity to methacholine increased in the week when this was measured. The proportion of eosinophils in peripheral blood, and urinary eosinophil protein X (EPX), decreased in both weeks. There was a trend towards an increase of eosinophil peroxidase (EPO) and myeloperoxidase (MPO) in sputum in the week when these proteins were measured. The concentrations of cat (Fel d1) and dog (Can f1) allergens were higher in dust collected in schools than in homes. Our results show that in children with mild asthma and animal dander allergy, there is a significantly increased bronchial sensitivity to methacholine after one school week. There is also a significant decrease in the number of circulating eosinophils and a trend towards an increase of sputum EPO, which could correlate with the early phase of eosinophil recruitment to the lungs. These effects may be related to the continuous exposure to animal allergens in school dust.     

Exercise-induced bronchoconstriction in children with atopic eczema

Non-specific bronchial hyper-responsiveness has been reported in most of the eczematous children even in the absence of asthmatic symptoms. We therefore investigated the occurrence of exercise-induced bronchoconstriction (EIB) in children with atopic eczema (AE) and the predictors of EIB. Fifty-five children referred to the paediatric clinic for AE and a control group of 17 healthy children were recruited. They all carried out a physical examination and skin prick test (SPT) both to inhalant and food allergens, prior to the exercise challenge test. Their parents filled a questionnaire on atopic diseases. They underwent exercise challenge test that consisted in free running for 6 min. Spirometric measurements were carried out before running and till 11 min after. Exercise challenge test was positive in 13 (23%) children with AE. None of the children in the control group had a positive exercise challenge test [OR (95% CI) = 1.31 (1.13-1.51); p = 0.030]. Sixteen (29%) eczematous children had a history of EIB. Such history was not reliable for identifying children who had a positive exercise test. Twenty-nine (52%) children with AE had asthma. Allergic rhinitis affected 33 (60%) of eczematous children and allergic conjunctivitis 28 (50%). EIB was not related to any history of asthma, allergic rhinitis, allergic conjunctivitis, severity of eczema or SPT results. Our study shows that EIB is common in children with AE. Our data also indicate that screening by medical history and physical examination is not a sensitive marker of EIB. This may explain why EIB is often ignored in eczematous children.     

Low-dose theophylline in childhood asthma: a placebo-controlled, double-blind study

Regular anti-inflammatory treatment is essential in treating persistent asthma. Most commonly, inhaled corticosteroids (ICS) are used. However, especially in children, there is concern about the long-term safety of ICS such that doses should be kept to a minimum. The use of theophylline has decreased because of frequent side-effects in therapeutic doses. In adults, there have been reports about an immunomodulatory effect of low-dose theophylline. To study the clinical and immunomodulatory effect in children, 36 patients (mean age 12.5 SD 2.4 years) with moderate, persistent asthma on regular ICS were recruited into a placebo-controlled, double-blind study. After a 6-week run-in period, patients received either theophylline 10 mg/kg bodyweight or placebo for 12 weeks. Diary cards, lung function, peripheral blood lymphocyte subpopulations and serum eosinophil cationic protein (sECP) were assessed. In the treatment group, mean serum theophylline was 7.1 mg/l. There was no change in symptoms or use of rescue medication. Mean (SD) peak expiratory flow (PEF) increased from 86% (24) to 95% (18) predicted. sECP decreased from 43.2 μg/l (32.5) to 26.5 μg/l (16.9) (p = 0.02). Lymphocyte subpopulations did not change. The study failed to show a beneficial clinical or an immunomodulatory effect of theophylline when used in low doses. These results do not support a more important role of theophylline in the long-term treatment of moderate childhood asthma.     

Specific IgE antibodies and serum eosinophil cationic protein in children with atopic dermatitis alone

Both eosinophils and specific immunoglobulin E (IgE) to foods and mites have been considered involved in the pathogenesis of atopic dermatitis (AD). The relationship between eosinophils and specific IgE, however, remains to be elucidated. Blood eosinophil counts, serum eosinophil cationic protein (ECP) and IgE to egg white, cow's milk, soybean, rice and Dermatophagoides pteronyssinus (Dp) were measured in subjects with AD alone or bronchial asthma (BA) alone. Subjects with positive IgE titers (Pharmacia radioallergosorbent test (RAST) units > 0.7) of one or more items were defined as RAST-positive. Immunoglobulin E titers to egg white, cow's milk and soybean of subjects with AD were high in early childhood and declined with aging, whereas the titers of subjects with BA were negative or low. Immunoglobulin E titers to Dp were elevated after 1 year of age in both disease groups. Eosinophil cationic protein (ECP) levels and blood eosinophil counts in the AD and BA groups were significantly higher than those of non-atopic controls. No difference in ECP levels or blood eosinophil counts were observed between RAST-positive and negative groups. It is concluded that IgE to foods such as egg white, cow's milk and soybean might have a role in the pathogenesis of AD of young children, while IgE to mites might be involved in older children. Eosinophils may also participate in AD. However, different mechanisms may be responsible for the rise in specific IgE and high ECP levels and blood eosinophil counts.     

Serum eosinophil cationic protein and interleukin-5 in children with bronchial asthma and acute bronchiolitis

The aim of our study was to evaluate the clinical applicability of serum eosinophil cationic protein (ECP), interleukin-5 (IL-5) and total eosinophil counts in childhood asthma and bronchiolitis. These parameters were measured in 44 children aged 12-84 months with moderate and mild asthma during symptomatic and asymptomatic phases of disease. Fifteen of the patients were included at the time of admission to hospital due to an acute asthmatic attack, and ten of these were also examined one month after discharge. None of the patients were treated with glucocorticoids or cromoglycate at any time during the study. Serum ECP was significantly increased in the children with acute asthma compared to children with stable moderate asthma, stable mild asthma, as well as to controls. There was no difference between the groups with stable asthma or between stable asthma and controls, and there was large overlap between all groups of asthmatics and controls. Detectable levels of circulating IL-5 were demonstrated in eight of 15 children with acute asthma, with significantly higher levels in atopic children, whereas all samples from children with stable asthma and controls were negative. The results suggest that even though serum ECP and IL-5 increases during acute asthmatic attacks, these parameters cannot alone be used to discriminate between different groups of young children with stable asthma, nor between asthmatics and healthy controls. In addition, the same parameters of eosinophil inflammation were examined in serum samples from 25 children aged 1-17 months undergoing their first episode of acute bronchiolitis. Children with acute respiratory syncytial virus (RS V) bronchiolitis had significantly higher levels of serum ECP than those with RSV negative disease, whereas the total eosinophil counts were significantly decreased in all patients with acute bronchiolitis. Serum IL-5 was only detected in two children with acute bronchiolitis. The results suggest that the inflammation in RSV bronchiolitis differs from that induced by other viruses.     

Survey of asthma deaths in the Northern region, 1970-85.

Thirty five asthma deaths in children aged 1 to 16 years were investigated in detail. Twenty four of these children had previously been under hospital consultant care and there were seven inpatient deaths. Twenty nine cases (83%) had a history of severe asthma, 17 of whom had previously experienced a life threatening attack. The fatal outcome, however, could not have been predicted in six children (17%) with preceding mild asthma. Potentially preventable factors in management were found in 28 cases (80%). While 18 (51%) had been chronically undertreated, the major factor in 20 deaths (57%) was suboptimal management of the final attack owing to delay in seeking medical attention, inadequate medical response, or both. Only two children had received systemic corticosteroid in appropriate amounts during the final illness. If mortality is to be reduced, families of asthmatic children must be educated to recognise severe symptoms and be given an appropriate ''crisis plan''. Hospitals should permit free access and have a clear protocol for the management of children with severe asthmatic attacks.     

血清Clara 细胞分泌蛋白、总IgE与嗜酸性粒细胞阳离子蛋白在儿童哮喘检测中的临床意义

目的探讨血清Clara细胞分泌蛋白（CC16）、总IgE和嗜酸性粒细胞阳离子蛋白（ECP）检测在哮喘儿童中的意义。方法采用酶联免疫吸附法（ELISA）测定59例哮喘患儿急性发作期血清CC16水平,同时应用UniCAP100变态反应检测仪检测血清总IgE、ECP;另设30例健康儿童作为健康对照组。结果与健康对照组比较,哮喘组血清CC16水平显著降低、血清总IgE、ECP水平显著增高（t=2.93,2.72,4.52Pa〈0.01）;中重度哮喘发作患儿血清CC16水平显著低于轻度发作患儿（t=5.26P〈0.05）,中重度哮喘发作患儿血清总IgE显著高于轻度发作患儿（t=3.89P〈0.05）,血清ECP水平在哮喘轻度发作组与中重度发作组比较无统计学差异（t=1.57P〉0.05）;哮喘组血清CC16与总IgE呈显著负相关（r=-0.602P〈0.05）,血清CC16与ECP（r=0.153P〉0.05）及总IgE与ECP（r=0.290P〉0.05）无相关。结论血清CC16降低与总IgE、ECP水平增高在儿童哮喘发病过程中发挥重要作用;血清总IgE、CC16可反映哮喘发作严重程度;血清ECP水平高低并不能反映呼吸道炎症严重程度。     

High levels of urinary eosinophil protein X in young asthmatic children predict persistent atopic asthma

Levels of urinary eosinophil protein X (U-EPX) and eosinophil counts were measured in 32 children (12–36 months of age) who were hospitalized for acute asthma, and the U-EPX levels were measured in 20 healthy children of the same age. The ability of these parameters to predict persistent asthma (at least one wheezing episode during the last 6 months) and atopic asthma (a positive skin-prick test [SPT]), was evaluated at a follow-up 2 years later. On admission, levels of U-EPX were higher in children with asthma (median: 120 µg/mmol of creatinine; quartiles: 67–123 µg/mmol of creatinine) than in controls (60 µg/mmol of creatinine, 38–74 µg/mmol of creatinine; p< 0.001). The U-EPX level was higher in those with persistent atopic asthma at follow-up (173 µg/mmol of creatinine, 123–196 µg/mmol of creatinine, n = 16), than in those with persistent non-atopic asthma (73 µg/mmol creatinine, 46–105 µg/mmol of creatinine, n = 8; p< 0.05), and higher than in those with transient asthma (no symptoms at follow-up) (106 µg/mmol creatinine; 42–167 µg/mmol of creatinine, n = 8; p< 0.05). By multiple logistic regression analysis, U-EPX was the only parameter able to predict persistent atopic asthma; eosinophil counts, parental atopy, age or gender could not. Parental atopy was the only parameter predictive for persistent asthma, regardless of atopic status. In conclusion, levels of U-EPX, but not eosinophil counts, measured in young children hospitalized with acute asthma can predict the persistence of atopic asthma 2 years later.     

Free running asthma screening test.

The free running asthma screening test (FRAST) was evaluated in 503 Sheffield schoolchildren aged 6 to 12 years and compared with responses to an asthma questionnaire. The FRAST measured peak expiratory flow rate (PEFR) before and at 1, 5, and 10 minutes after maximum voluntary running for at least 5 minutes in a standardised environment. A fall in PEFR of greater than 15% in at least two postexercise readings was defined as abnormal. Six (1%) children did not do the test and 69 (14%) failed to complete it. Of these, 14 were known asthmatics, 18 were not testable, and 37 were normal when retested. There were 14 abnormal FRAST results among 412 ''normal'' children who completed the test and 10 of these were subsequently diagnosed asthmatic. None of 14 children with an abnormal FRAST result had been identified as wheezy, chesty, or asthmatic in the questionnaire. In this sample there was, on average, one child in every school class with unrecognised exercise induced bronchospasm. The FRAST is an acceptable, feasible, and cost effective way of identifying such potential asthmatics at school.     

Circadian variations in serum eosinophil cationic protein, and serum and urine eosinophil protein X

Biochemical evaluation of inflammation may be a useful adjunct to measures of pulmonary function and symptoms in children with asthma. However, little data have been provided to validate the markers in children. The aim of the present study was to assess circadian variations in serum eosinophil cationic protein (ECP), and serum and urine eosinophil protein X (EPX) in children. Five girls and two boys aged 10–14 years were studied. The first sample of urine consisted of urine collected from 24.00 hours the night before until 08.00 hours on the morning of the day of investigation. Thereafter urine was collected at 4-h intervals until 24.00 hours and in another 8-h interval from 24.00 to 08.00 hours. Blood samples for assessment of serum ECP and serum EPX were collected every 2 h during the 24 h. Statistically significant circadian variations in serum ECP (F=3.2, p=0.002), serum EPX (F=3.1, p=0.002) and in urine EPX/creatinine (F=5.4, p=0.003) were detected. The concentrations were higher during the night compared to daytime. Peak levels of serum ECP (mean [± SEM]) were found at 06.00 hours (16.3 [5.3] µg/l), trough levels at 08.00 hours (3.9 [0.7] µg/l) (p=0.01). Peak levels of serum EPX were seen at 06.00 (43.7 [9.5] µg/l) with trough levels at 12.00 hours (22.0 [3.5] µg/l) (p=0.01). Peak levels of urine EPX/creatinine occurred in urine collected from 24.00 to 08.00 hours (90.0 [27.7] µg/mmol), trough levels in the 16.00–20.00 hours sample (29.7 [8.9] µg/mmol) (p=0.02). Serum ECP, serum EPX and urine EPX exhibit a circadian variation in children with nocturnal and early morning peak levels. To avoid confounding influence from circadian variations in ECP and EPX in clinical studies blood or urine should be sampled at consistent times.     

Perceptions of Asthma and Exercise,and Associations With Weight Status and Asthma Morbidity in Urban Children

BackgroundGiven the high prevalence of asthma and obesity in minority children, there is a need to identify targets for intervention to decrease the impact of these conditions on children's functioning in this high-risk group.ObjectiveTo examine in urban children with persistent asthma, 1) differences in asthma indicators (eg, FEV1% predicted) by weight status, and by ethnic group/weight status, 2) caregivers’ fears about their child's asthma by weight status, and by ethnic group/weight status, and 3) the proportion of children who qualified for exercise-induced bronchospasm (EIB) via exercise challenge test among those whose caregivers endorse exercise as a trigger for asthma.MethodsIn this sample of urban children (aged 7–9; N = 147), subjective measures included child/caregiver daily report of asthma symptoms and caregiver fears about their child's asthma. Objective lung function was measured twice daily via handheld spirometer and EIB was confirmed via exercise challenge test.ResultsIn the overall sample, a greater proportion of normal-weight children reported asthma symptoms compared to overweight/obese children. Caregiver fears about asthma were more prevalent among Latino caregivers. Non-Latino White children whose caregivers were afraid their child may die when having asthma reported more days with asthma symptoms. Very few children had confirmed EIB compared to the proportion of caregivers who endorsed exercise as a dangerous trigger for asthma.ConclusionsCaregiver fear about asthma and misperceptions of exercise as a dangerous trigger for asthma should be addressed during health care visits with families of children with asthma and interventions including urban children with asthma.     

Screening a state middle school for asthma using the free running asthma screening test.

The free running asthma screening test (FRAST) was used to screen children in a state middle school during a normal physical education lesson. The test was conducted by the teachers with a general practitioner available via a radiopager. Of the 249 children attending the school, aged 8-12 years, 237 (95%) were tested. Twenty two (9%) children were known to have asthma, of whom 18 were tested. Thirty one children had a significant decrease (> 15%) in their peak expiratory flow rate (PEFR) after exercise. Six of these children were known to have asthma, indicating that their asthma treatment may be suboptimal. A further six children assessed clinically had false positive results. The 31 children with significant decreases in their PEFR were matched for age and sex with a control group of 30 children who were considered to have a normal result. Of the control group, one child had clinical asthma. In total, 19 (8%) new cases of asthma were identified, giving an overall prevalence of asthma in the school of 16%. These results indicate that it is feasible to screen schools for asthma using the FRAST. Children with undiagnosed asthma can be identified and the control of children with known asthma monitored.     

Screening a state middle school for asthma using the free running asthma screening test

The free running asthma screening test (FRAST) was used to screen children in a state middle school during a normal physical education lesson. The test was conducted by the teachers with a general practitioner available via a radiopager. Of the 249 children attending the school, aged 8-12 years, 237 (95%) were tested. Twenty two (9%) children were known to have asthma, of whom 18 were tested. Thirty one children had a significant decrease (> 15%) in their peak expiratory flow rate (PEFR) after exercise. Six of these children were known to have asthma, indicating that their asthma treatment may be suboptimal. A further six children assessed clinically had false positive results. The 31 children with significant decreases in their PEFR were matched for age and sex with a control group of 30 children who were considered to have a normal result. Of the control group, one child had clinical asthma. In total, 19 (8%) new cases of asthma were identified, giving an overall prevalence of asthma in the school of 16%. These results indicate that it is feasible to screen schools for asthma using the FRAST. Children with undiagnosed asthma can be identified and the control of children with known asthma monitored.     

哮喘患儿诱导痰Clara细胞分泌蛋白与嗜酸性粒细胞阳离子蛋白检测的意义

目的探讨Clara细胞分泌蛋白（CCSP）与嗜酸性粒细胞阳离子蛋白（ECP）在儿童支气管哮喘发病机制中的作用,评价其反映哮喘呼吸道炎症的价值。方法本院哮喘专科患儿31例。男18例,女13例;年龄3.7-12.0岁,平均7.6岁;均按全球哮喘防治创议（GINA）方案系统吸入糖皮质激素治疗,在慢性持续期和临床缓解期分别留取诱导痰标本。用酶联免疫吸附法（ELISA）测定CCSP水平,以Pharmacia UniCAP系统检测ECP水平。结果哮喘慢性持续期患儿诱导痰CCSP质量浓度明显低于临床缓解期（P〈0.001）,而ECP水平明显高于临床缓解期（P〈0.001）,且二者之间呈负相关（r=-0.676P〈0.001）。结论CCSP在哮喘的发病过程中起抗炎作用,而ECP起促炎作用,同时监测诱导痰CCSP、ECP的变化,可较好地反映呼吸道炎症情况,评价疗效及预后。     

支气管可逆性试验对哮喘儿童治疗的指导意义

目的：观察哮喘治疗期间不同临床症状患儿肺功能的变化,探讨支气管可逆性试验对儿童哮喘治疗的指导意义。方法：417例哮喘患儿通过吸入沙美特罗/氟替卡松治疗时间3个月以上。复诊时根据患儿症状分为无症状组（n=215）、单咳组（n=89）、阵咳组（n=72）和喘咳组（n=41）。34例正常儿童作为对照组。应用沙丁胺醇泵雾化进行支气管可逆性试验,试验前后行肺功能检测。结果：各个哮喘组沙丁胺醇雾化后肺功能异常率较雾化前均明显降低,FEV1%/预测值雾化后均较雾化前显著升高（P<0.05）。雾化前单咳组、阵咳组、喘咳组肺功能异常率均较对照组显著增高,FEV1%/预测值均较对照组显著降低（P<0.05）;雾化前各个不同症状哮喘组间肺功能异常率及FEV1%/预测值差异有统计学意义（P<0.05）。雾化后阵咳组、喘咳组肺功能异常率明显高于对照组（P<0.05）,其他各组与对照组比较差异无统计学意义;雾化后喘咳组FEV1%/预测值明显低于对照组,其他各组与对照组比较差异无统计学意义。不同症状的4个哮喘组支气管可逆性试验阳性率均高于对照组（P<0.05）;各个哮喘组间可逆性试验阳性率比较,除无症状组与单咳组差异无统计学意义外,其余各组间差异均有统计学意义（P<0.05）。结论：儿童哮喘治疗期间不同症状者肺功能存在差异;支气管可逆性试验结合肺功能检查有利于哮喘控制的评估和治疗指导。