Predictors of hospitalization for asthma in children: results of a 1-year prospective study

INTRODUCTION

Although hospital admissions for pediatric asthma constitute a significant problem in high-income countries, they are an even greater health problem in low- and middle-income countries (LMIC). However, previous studies that aimed to identify predictors of hospital admission for asthma in children have mainly been conducted in high-income countries, and these findings might not be applicable to LMIC.

METHODS

In a prospective cohort study, we aimed to identify predictors of hospital admission for asthma, including measures of parental knowledge about asthma and maternal depression level, in a population of children aged 1-18 years living in urban Bogota, Colombia hospitalized for acute asthma symptoms, over a 6-month period.

RESULTS

Out of the total of 101 included patients, 37 (36.6%) had at least one hospital admission for asthma during the year following admission. After controlling for the age of the patients, dog ownership in the previous 12 months, asthma severity variables in the previous 6 months, maternal allergic rhinitis, level of maternal education, and measures of parental knowledge about asthma and maternal depression level, we found that maternal smoking (IRR, 3.12; 95% confidence interval [95% CI], 1.12-8.68; P = 0.029) was the only independent predictor of hospital admissions due to asthma exacerbations in the year following admission to the study.

CONCLUSIONS

In a population of asthmatic Latino children admitted to hospital for an asthma exacerbation, approximately one-third of the patients had at least one hospital admission for asthma during the year following admission, and maternal smoking was the only independent predictor of these hospitalizations.

Principal findings of systematic reviews for chronic treatment in childhood asthma

OBJECTIVE

To summarize the principal findings pertaining to most effective long-term pharmacologic treatment of childhood asthma.

METHODS

Systematic reviews of randomized clinical trials (SRCTs) on pharmacologic chronic treatment in children (1-18 years) with persistent asthma were retrieved through MEDLINE, EMBASE, CINAHL, SCOPUS, and CDSR (up to January2014).

RESULTS

One hundred eighty-three SRCTs were searched from databases. Among those, 39 SRCTs were included: two were related to step 1, 24 to step 2, nine to steps 3 and 4, and four to step 5 (according with NAEPP and GINA guidelines). The methodological quality of these SRCTs was determined by using the AMSTAR tool.

RESULTS

For step 1: addition of ipatropium bromide to short-acting beta2-agonists does not show any benefit. For step 2: in preschoolers, inhaled corticosteroids (ICSs) reduce severe exacerbations and improve other clinical and lung function parameters. In children, ICSs are superior to leukotriene receptor antagonist (LTRA), cromones, or xantines in reducing severe exacerbations, improving lung function and other clinical outcomes. Fluticasone propionate (FP) is better than beclomethasone dipropionate (BDP) or budesonide only for lung function; but similar to hydrofluoroalkane-BDP or to ciclosenide. Compared to low ICSs doses, moderate doses result in only better lung function, but this is not true for FP. For steps 3 and 4: adding LTRA to ICS confers a small benefit; adding LABA improves lung function but does not reduce exacerbations more than double or higher ICS doses. For step 5: adding omalizumab decreases exacerbations.

CONCLUSIONS

SRCTs are useful for guiding decisions in chronic childhood asthma treatment.

Postinfectious bronchiolitis obliterans in children: the South American contribution

Postinfectious bronchiolitis obliterans (PIBO) is an infrequent chronic lung that causes irreversible obstruction and, or, obliteration of the smaller airways. This review particularly focuses on more than 30 studies from South America.

CONCLUSION

The initial PIBO event occurs in the early years of life and is strongly associated with adenovirus infection and the need for mechanical ventilator support. Treatment requires a multidisciplinary strategy. Multicentre studies are needed to determine progression, optimal management and long-term follow-up.

Chest physiotherapy is not clinically indicated for infants receiving outpatient care for acute wheezing episodes

AIM

To evaluate the effectiveness of chest physiotherapy (CPT), which provides slow and long expiratory flow and assisted cough techniques, in infants receiving outpatient care for acute wheezing episodes.

METHODS

Forty-eight infants with moderate acute wheezing episodes were randomised to receive either salbutamol MDI with CPT (n = 25) or without CPT (n = 23). The clinical score and SpO2 levels were recorded, before and after treatment, in a blinded design. The primary outcome was discharge after the first hour of treatment: clinical score ≤5/12 and SpO2 ≥ 93%. Secondary outcomes were the number of admissions to hospital after the second hour, use of oral corticosteroid bursts and admissions to hospital on day seven.

RESULTS

There were no differences between children with and without CPT in discharge rate (92% vs. 87%), clinical score (median [IQR]: 2.8 [2.2-3.3] vs. 3.4 [2.8-4.1]) and SpO2 = (96.4 [95.7-97.1] vs. 96.0 [94.9-96.5]) after the first hour of treatment or in the number of hospital admissions after the second hour. No differences were observed at days seven and 28 following treatment.

CONCLUSION

There was no evidence of clinical benefits from these specific CPT techniques for infants receiving outpatient care for acute wheezing episodes.

Inhaled versus systemic corticosteroids for acute asthma in children. A systematic review

OBJECTIVE

To compare the effects of inhaled corticosteroids (ICS) against systemic corticosteroids (SC) in children consulting in emergency department (ED) or equivalent for asthma exacerbation.

METHODS

Electronic search in MEDLINE, CENTRAL, CINAHL, and LILACS databases and other sources. Study selection criteria: children 2-18 years of age, consulting in ED or equivalent for asthma exacerbation, comparison between ICS and SC, randomized controlled trials.

PRIMARY OUTCOMES

hospital admission rate, unscheduled visits for asthma symptoms, need of additional course of SC.

SECONDARY OUTCOMES

improvement of lung function, length of stay in ED, clinical scores, and adverse effects.

RESULTS

Eight studies met inclusion criteria (N = 797), published between 1995 and 2006. All used prednisolone as SC and budesonide, fluticasone, dexamethasone, and flunisolide were administered as ICS. No significant difference between ICS versus SC was found in terms of hospital admission (RR: 1.02; 95% CI: 0.41-2.57), unscheduled visits for asthma symptoms (RR: 9.55; 95% CI: 0.53-170.52) nor for need of additional course of SC (RR: 1.45; 95% CI: 0.28-7.62). The change in % of predicted FEV1 at fourth hour was significantly higher for SC group, but there was no significant difference between both groups after this time. There was insufficient data to perform meta-analysis of length of stay during first consult in ED and of symptom scores. Vomiting was similar among both groups.

CONCLUSIONS

There is no evidence of a difference between ICS and SC in terms of hospital admission rates, unscheduled visits for asthma symptoms and need of additional course of SC in children consulting for asthma exacerbations.

Validation of the Spanish version of the Test for Respiratory and Asthma Control in Kids (TRACK) in a population of Hispanic preschoolers

BACKGROUND

There is a critical need for validation studies of questionnaires designed to assess the level of control of asthma in children younger than 5 years old.

OBJECTIVE

To validate the Spanish version of the Test for Respiratory and Asthma Control in Kids (TRACK) questionnaire in children younger than age 5 years with symptoms consistent with asthma.

METHODS

In a prospective cohort validation study, parents and/or caregivers of children younger than age 5 years and with symptoms consistent with asthma, during a baseline and a follow-up visit 2 to 6 weeks later, completed the information required to assess the content validity, criterion validity, construct validity, test-retest reliability, sensitivity to change, internal consistency reliability, and usability of the TRACK questionnaire.

RESULTS

Median (interquartile range) of the TRACK scores were significantly different between patients with well-controlled asthma, patients with not well-controlled asthma, and patients with very poorly controlled asthma (90.0 [75.0-95.0], 75.0 [55.0-85.0], and 35.0 [25.0-55.0], respectively, P < .001). TRACK scores were significantly different between patients classified as currently symptomatic and symptomatic in the recent past (42.5 [25.0-55.0] vs 85.0 [75.0-90.0]; P < .001). The intraclass correlation coefficient of the measurements was 0.755 (95% CI, 0.503-1.00). All patients whose clinical status changed showed an increase of 10 or more points in TRACK score between baseline and follow-up visits. The Cronbach α was 0.77 for the questionnaire as a whole.

CONCLUSION

The Spanish version of the TRACK questionnaire has excellent sensitivity to change and usability; adequate criterion validity, construct validity, and test-retest reliability; and an acceptable internal consistency, when used in children younger than age 5 years with symptoms consistent with asthma.

Correlation between nitrites in induced sputum and asthma symptoms in asthmatic schoolchildren

OBJECTIVE

To determine if nitrites (nitric oxide metabolites) measured in induced sputum decrease and correlate with improvement of clinical asthma symptoms after treatment, we performed a prospective longitudinal study in a tertiary care hospital in Arequipa, Peru.

METHODS

In 95 schoolchildren with mild and moderate persistent asthma we determined nitrites in induced sputum samples (measured using the Griess assay). Clinical parameters and exercise bronchial challenge (EBC) test were performed twice, at baseline and after 3 months of beclomethasone-dipropionate treatment (median doses: 300 mcg/day, IQR: 300-450).

RESULTS

Sixty out of 95 children completed the study (median age of 9-year [IQR: 7-13]). A significant change in sputum nitrites levels between admission and the end of the study was observed (34.4 nmol/ml [IQR:18.2-58.4] and 11.2 nmol/ml [6-20.1], respectively, P = < 0.0001). Also a significant correlation between decrease of sputum nitrites levels and improvement of clinical parameters (acute exacerbations [r = 0.361, P = 0.005]; use of salbutamol [r = 0.322, P = 0.013]; emergency visits [r = 0.275, P = 0.033]; and school absence [r = 0.41, P = 0.001]) from admission to the end of the study was found. However, sputum nitrites levels did not correlated with peripherical blood eosinophils or serum IgE levels or with EBC test at any point of the study. The decrease of sputum nitrites levels after the treatment was significant in each asthma group (mild and moderate), but not between groups.

CONCLUSION

This study showed that measured nitrite in induced sputum (a simple and cheap non-invasive method) is a good alternative for monitoring asthmatic treatment in schoolchildren.

Effect of obesity on bronchial hyperreactivity among Latino children

BACKGROUND

The association between obesity and bronchial hyperreactivity (BHR) in children has not been fully demonstrated in cross-sectional or longitudinal studies, and no study has specifically addressed Latino children.

METHODS

A cross-sectional study of 450 children (10-18 years) from public schools was conducted in Mexico city. Among this group, 260 met the study criteria (no chronic respiratory illnesses, including asthma and rhinitis; no acute respiratory infections; and no tobacco-exposure or endocrine or body dysmorphic disorders), and 229 performed reproducible pulmonary function and methacholine challenge tests and were fully analyzed.

RESULTS

According to BMI percentiles, 40 were normal weight, 116 were obese, and 73 morbidly obese. Children in the morbidly obese group had significantly higher % FVC than those in the normal-weight group, and obese children had higher % PEF those in the morbidly obese and normal-weight groups. In the BHR methacholine challenge test, baseline FEV1 values among obese children were significantly lower than in the morbidly obese group. Using adjusted percentages for FEV1 , values were significantly lower among obese compared to morbidly obese children at metacholine concentrations of 0.25, 1, and 4 mg/ml. The proportion of positive BHR (PC20  ≤ 16 mg/ml) was higher in these two groups compared to normal-weight children (28.4%, 17.8%, and 12.5%, respectively), although differences were not significant.

CONCLUSION

Our findings show that obesity by itself is not a sufficient condition to alter airway responsiveness to methacholine in a group of adolescents.

Influence of Mediterranean diet on asthma in children: a systematic review and meta-analysis

BACKGROUND

There is epidemiological evidence that Mediterranean diet exposure is associated with lower asthma prevalence in children. We aimed to summarize the available data and to know whether the Mediterranean setting modifies this association.

METHODS

The literature search, up to May 2012, was on epidemiological studies in the general population of children assessing whether adherence to Mediterranean diet (measured as a score) was associated with the prevalence of 'current wheeze'; 'current severe wheeze'; or 'asthma ever'. Odds ratios (OR) of the eight included studies compared the highest tertile of the score with the lowest. Random-effects meta-analyses for the whole group of studies and stratified by Mediterranean setting (centers <100 Km from the Mediterranean coast) were performed. Differences between strata were assessed using the Q test.

RESULTS

For 'current wheeze', there was a negative significant association with the highest tertile of Mediterranean diet score (OR 0.85, 95% CI 0.75-0.98; p = 0.02), driven by Mediterranean centers (0.79, 0.66-0.94, p = 0.009), although the difference with the non-Mediterranean centers (0.91, 0.78-1.05, p = 0.18) was not significant. The results for 'current severe wheeze' were as follows: 0.82, 0.55-1.22, p = 0.330 (all); 0.66, 0.48-0.90, p = 0.008 (Mediterranean); and 0.99, 0.79-1.25, p = 0.95 (non-Mediterranean); with the difference between regions being significant. For 'asthma ever', the associations were as follows: 0.86, 0.78-0.95, p = 0.004 (all); 0.86, 0.74-1.01, p = 0.06 (Mediterranean); 0.86, 0.75-0.98; p = 0.027 (non-Mediterranean); with the difference between regions being negligible.

CONCLUSIONS

Adherence to the Mediterranean diet tended to be associated with lower occurrence of the three respiratory outcomes. For current and current severe wheeze, the association was mainly driven by the results in Mediterranean populations.

Young infants with recurrent wheezing and positive asthma predictive index have higher levels of exhaled nitric oxide

OBJECTIVE

The aim of this post hoc analysis was to establish the relationship between FE(NO) levels and the asthma predictive index (API) among infants with recurrent wheezing.

METHODS

Infants with recurrent wheezing (three or more episodes) were recruited consecutively and online FE(NO) tests at tidal breathing with multiple breaths were performed.

RESULTS

Twenty-seven (84%) out of 32 infants (median age of 12 months) who met the inclusion criteria for this post hoc analysis, successfully performed the FE(NO) determinations. Eighteen (66%) infants were classified with positive stringent API. FE(NO) levels were significantly higher among patients with positive API than those with negative (median [IQR] of 12.3 [14.8] ppb vs. 4.1 [7.9] ppb, respectively, p = .016). Furthermore, FE(NO) and positive API had a significant correlation (Spearman's rho, ρ = 0.4741, p = .0125). After logistic regression analysis including FE(NO) levels, gender, age, and use of controller therapy, FE(NO) was the only variable that was marginally related to API (OR = 1.12, 95% CI: 0.99-1.27, p = .07).

CONCLUSION

Infants with recurrent wheezing who had a positive stringent API already had higher FE(NO) levels than those with a negative API. This finding needs to be corroborated in a larger prospective study.

Chest physiotherapy in paediatric patients hospitalised with community-acquired pneumonia: a randomised clinical trial

BACKGROUND

Chest physiotherapy has been used to treat children hospitalised with pneumonia with no clear scientific evidence to support a beneficial effect. The objective of the current study was to evaluate the efficacy of chest physiotherapy as an adjuvant treatment in children hospitalised with acute community-acquired pneumonia.

METHODS

Children (aged 1-12 years) with a clinical and confirmed radiological diagnosis of pneumonia sequentially admitted to a tertiary children hospital were eligible for this study. Participants were randomly selected to receive a standardised respiratory physiotherapy (positioning, thoracic vibration, thoracic compression, positive expiratory pressure, breathing exercises and forced exhalation with the glottis open or 'huffing') three times daily in the 'intervention group' or a non-mandatory request to breathe deeply, expectorate the sputum and maintain a lateral body position once a day in the 'control group'. The primary outcomes were reduction in respiratory rate and severity score (respiratory rate, recession, fever, oxygen saturation and chest x-ray) from baseline to discharge. Secondary outcome was duration of hospitalisation.

RESULTS

In all, 72 patients were randomly allocated to the intervention (n=35) or control (n=37) groups. There were no differences at admission on severity of pneumonia between groups. Respiratory rate and severity score significant decreased between admission to discharge within each group; however, there were no differences when comparing groups. Also, there was no significant difference in duration of hospitalisation between the control and intervention groups (6 vs 8 days, p=0.11, respectively).

CONCLUSIONS

This clinical trial suggests that, in children hospitalised with moderate community-acquired pneumonia, chest physiotherapy did not have clinical benefits in comparison to control group.

Comparison of the bronchodilating effects of albuterol delivered by valved vs. non-valved spacers in pediatric asthma

INTRODUCTION

Inhaled therapy using a metered-dose inhaler (MDI) with attached valved holding chamber has been increasingly recognized as the optimal method for delivering bronchodilators for asthma treatment. However, mainly due to the high cost of these valved holding chambers in many developing countries, the use of non-valved spacers is frequent, despite the scarce evidence that supports their efficacy. The aim of this study was to compare the bronchodilator response to albuterol administered by MDI with and without a valved spacer.

METHODS

In a randomized, two-period, two-sequence crossover clinical trial, we analyzed 31 stable asthmatic children (6-18 yrs of age) on two consecutive days, who were randomly assigned to receive 100 μg of albuterol MDI through either a locally produced valved spacer or a non-valved spacer. The next day, a crossover treatment was employed through the use of the other spacer. Spirometry was recorded before and after each albuterol administration.

RESULTS

As we were not able to identify any sequence or carryover effect, we tested for treatment effects in both periods. No significant differences in the absolute change in FEV(1) (0.20 ± 0.17 vs. 0.18 ± 0.16, p = 0.63), FVC (0.07 ± 0.13 vs. 0.07 ± 0.16, p = 0.88), or MMEF (0.49 ± 0.31 vs. 0.43 ± 0.39, p = 0.53) after bronchodilator administration were found between the use of valved and non-valved spacers.

CONCLUSIONS

In stable asthmatic children, albuterol administered through MDI using a non-valved spacer produces a bronchodilator response similar to that of a spacer with a valve that requires an inhalatory opening pressure (with flows between 2 and 32 l/min) that even toddlers with bronchial obstruction can easily generate.

A systematic review of long-acting β2-agonists versus higher doses of inhaled corticosteroids in asthma

OBJECTIVE

To compare the efficacy of inhaled corticosteroids (ICS) plus long-acting β2 agonist (LABA) versus higher doses of ICS in children/adolescents with uncontrolled persistent asthma.

METHODS

Randomized, prospective, controlled trials published January 1996 to January 2012 with a minimum of 4 weeks of LABA+ICS versus higher doses of ICS were retrieved through Medline, Embase, Central, and manufacturer's databases. The primary outcome was asthma exacerbations requiring systemic corticosteroids; secondary outcomes were the pulmonary function test (PEF), withdrawals during the treatment period, days without symptoms, use of rescue medication, and adverse events.

RESULTS

Nine studies (n = 1641 patients) met criteria for inclusion (7 compared LABA+ICS versus double ICS doses and 2 LABA+ICS versus higher than double ICS doses). There was no statistically significant difference in the number of patients with asthma exacerbations requiring systemic corticosteroids between children receiving LABA+ICS and those receiving higher doses of ICS (odds ratio = 0.76; 95% confidence interval: 0.48-1.22, P = .25, I(2) = 16%). In the subgroup analysis, patients receiving LABA+ICS showed a decreased risk of asthma exacerbations compared with higher than twice ICS doses (odds ratio = 0.48; 95% confidence interval: 0.28-0.82, P = .007, I(2)= 0). Children treated with LABA+ICS had significantly higher PEF, less use of rescue medication, and higher short-term growth than those on higher ICS doses. There were no other significant differences in adverse events.

CONCLUSIONS

There were no statistically significant group differences between ICS+LABA and double doses of ICS in reducing the incidence of asthma exacerbations but it did decrease the risk comparing to higher than double doses of ICS.

International consensus on (ICON) pediatric asthma

Asthma is the most common chronic lower respiratory disease in childhood throughout the world. Several guidelines and/or consensus documents are available to support medical decisions on pediatric asthma. Although there is no doubt that the use of common systematic approaches for management can considerably improve outcomes, dissemination and implementation of these are still major challenges. Consequently, the International Collaboration in Asthma, Allergy and Immunology (iCAALL), recently formed by the EAACI, AAAAI, ACAAI, and WAO, has decided to propose an International Consensus on (ICON) Pediatric Asthma. The purpose of this document is to highlight the key messages that are common to many of the existing guidelines, while critically reviewing and commenting on any differences, thus providing a concise reference. The principles of pediatric asthma management are generally accepted. Overall, the treatment goal is disease control. To achieve this, patients and their parents should be educated to optimally manage the disease, in collaboration with healthcare professionals. Identification and avoidance of triggers is also of significant importance. Assessment and monitoring should be performed regularly to re-evaluate and fine-tune treatment. Pharmacotherapy is the cornerstone of treatment. The optimal use of medication can, in most cases, help patients control symptoms and reduce the risk for future morbidity. The management of exacerbations is a major consideration, independent of chronic treatment. There is a trend toward considering phenotype-specific treatment choices; however, this goal has not yet been achieved.

Urinary leukotriene excretion profile in children with exercise-induced asthma compared with controls: a preliminary study

BACKGROUND

Leukotrienes are among the most important mediators associated with inflammatory responses in patients with exercise induced asthma (EIA). The aim of this study was to investigate the impact of exercise on the urinary leukotriene profile. Hence, we compared post exercise changes of urinary leukotriene E4 (LTE4) concentration between children with EIA and healthy controls.

METHODS

Ten children with EIA and 15 controls were enrolled. Both groups underwent a standardised exercise challenge test (ECT). LTE4 concentration was measured in urine samples obtained pre and post ECT, using enzyme immunoassay and adjusted by urinary creatinine concentrations.

RESULTS

Median (minimum-maximum) pre ECT concentration of LTE4 was 17.82 (7.58-90.23 pg/ml) in EIA and 17.24 (4.64-64.02 pg/ml) in controls, p=0.86. LTE4 concentration post ECT were 23.37 (4.02-93.00 pg/ml) in EIA and 11.74 (0.13-25.09 pg/ml) in controls, p=0.02. Changes of LTE4 concentration post ECT were 2.54 (-31.98 to 43.31 pg/ml) in cases and -13.53 (-46.00 to 11.02 pg/ml) in controls, p=0.03. There was no significant correlation between basal predicted FEV(1) [%] and changes in LTE4 concentration in cases (i.e., r(s)=0.14) nor controls (i.e., r(s)=0.12). There was a tendency towards more pronounced changes in LTE4 concentration post ECT in children with moderate/mild persistent asthma compared to those with mild but intermittent asthma.

CONCLUSIONS

Children with EIA had significantly higher changes of urinary LTE4 concentrations post ECT compared to healthy controls. Urinary measurement of LTE4 may be an interesting and non-invasive option to assess control of EIA in children.

Discriminative properties of two predictive indices for asthma diagnosis in a sample of preschoolers with recurrent wheezing

INTRODUCTION

It is important to predict if preschool children with recurrent wheezing will suffer from asthma in future years. To aid in this early identification, a number of asthma predictive scores have been reported, such as the asthma predictive index (API) and the PIAMA risk score. However, to the best of our knowledge, their predictive properties have not been evaluated in any lower- to middle-income country.

MATERIALS AND METHODS

A prospective cohort study was carried out including preschoolers aged 1-3 years with recurrent wheezing who came to our Pediatric Pulmonary Unit in Bogota, Colombia. We collected the information required to complete the API index and the PIAMA risk score. At 5-6 years of age, the patients were contacted in order to determine if they were suffering from active asthma. We calculated the sensitivity, specificity, predictive values, and likelihood ratios (LR) of the API and PIAMA risk scores for the presence of active asthma at 5-6 years old.

RESULTS

The mean age at recruitment of the 130 included patients was 27.2 ± 5.9 months. The loose API yielded a sensitivity of 71.4% (95% CI: 50.0-86.2), specificity of 33.3% (95% CI 23.5-44.8), and positive predictive value of 23.8% (95% CI: 15.0-35.6). The stringent API yielded a sensitivity of 42.9% (95% CI: 24.5-63.5), specificity of 79.2% (95% CI 68.4-86.9), positive predictive value of 37.5% (95% CI: 21.2-57.3), and positive LR of 2.06. The PIAMA risk score yielded a sensitivity of 54.5% (95% CI: 42.6-66.0), specificity of 78.9 (95% CI: 66.7-87.5), positive predictive value of 75.0 (95% CI: 61.2-85.1), and positive LR of 2.59.

CONCLUSIONS

Our results suggest that both indices can be used to predict asthma in preschoolers with recurrent wheezing in the context of a referral hospital.

Exercise challenge test: is a 15% fall in FEV(1) sufficient for diagnosis?

INTRODUCTION

In the exercise challenge test (ECT), a drop in forced expiratory volume in the first second (FEV(1)) of between 10 and 15% is the determinant variable for a diagnosis of exercise-induced bronchospasm.

HYPOTHESIS

The use of FEV(1) plus mean forced expiratory flow between 25% and 75% of the forced vital capacity (FEF(25-75%)) may increase the sensitivity of the ECT in asthmatic children.

SPECIFIC OBJECTIVE

To compare FEV(1) and FEF(25-75%) changes in a group of asthmatic and healthy children.

METHODOLOGY

This was a cross-sectional study. Asthmatics were categorized by their severity (GINA) and after 1 month without controller therapy, an ECT was done under standard protocol. As well, a questionnaire about rhinitis and asthma was conducted with the entire population. ROC curves were used for analysis.

RESULTS

A total of 147 children (34 healthy and 113 asthmatics, 18 and 58 males, respectively) were evaluated. Divided into healthy children and intermittent, mild and moderate persistent asthmatics, they had similar average ages (9.4, 9.48, 8.97, and 11.2 years, respectively). Using a 15% fall in FEV(1), we obtained 29% sensitivity and 100% specificity. However, when we used a 10% fall in FEV(1), sensitivity was 47% and specificity was 97%. Adding a 28% fall in FEF(25-75%), sensitivity was 52% and specificity was 94%.

CONCLUSION

This study suggests that test sensitivity can increase by using a lower FEV(1) cut-off (10%) and adding a 28% fall in FEF(25-75%).

Post infectious bronchiolitis obliterans in children

Bronchiolitis Obliterans (BO) is an infrequent chronic and obstructive lung disease secondary to an insult to the terminal airway and its surroundings. In children, the most common presentation is the post-infectious variant, closely related to a severe viral infection in the first three years of life. However, the increase in the number of lung and bone-marrow transplants has also been followed by an increase in post-transplant BO. Post-transplant BO is progressive while post-infectious BO does not seem to be, but both forms share some common pathways that result in a characteristic histopathology of bronchiolar obliteration. This review covers up-to-date evidence on epidemiology, diagnosis, treatment and prognosis of post-infectious bronchiolitis obliterans, including areas of controversy that need to be addressed in future studies.

Bronchial hyperreactivity to methacholine in atopic versus nonatopic asthmatic schoolchildren and preschoolers

BACKGROUND

Atopy and bronchial hyperreactivity are factors related to severe and unremitting asthma of childhood; however, the prevalence of these factors could be different according to age of the child.

OBJECTIVE

To determine if methacholine bronchial hyperreactivity (BHR) differs between atopic and nonatopic preschoolers and schoolchildren with mild-moderate asthma.

METHODS

Data obtained from 340 children with diagnosis of asthma or recurrent wheezing, matched by atopic conditions (positive or negative skin prick test) and age, and who underwent a methacholine bronchial challenge test (by spirometry in schoolchildren and by transcutaneous oxygen pressure [TcP(O₂)] in preschoolers) were reviewed.

RESULTS

Among 136 schoolchildren (9.07 ± 2.5 years), the prevalence of positive BHR was significantly higher among atopics than nonatopics (75% versus 48.5%, p = .001, respectively), even after controlling for gender and nutritional status (adjusted odds ratio [aOR] = 3.2129, 95% confidence interval [CI]: 1.5-6.8; p = .002). In addition, atopic schoolchildren had lower PC(20) and required a lower threshold dose of methacholine to induce a reaction (0.53 versus 0.82 mg/ml, p = .055 and .5 versus 1 mg/ml, p = .02, respectively) than nonatopics. Nevertheless, basal and predicted forced expiratory volume in one second (FEV₁) were similar between groups. In contrast, among 204 preschoolers (4.74 ± 1.1 years), there were no differences in the prevalence of positive BHR between atopics and nonatopics (74.5% versus 72.5%, p = .75, respectively). Furthermore, basal TcP(O₂), a higher fall of TcP(O₂) and lower threshold doses of methacholine required for induction as measured by TcP(O₂) were similar between the atopic and nonatopic preschoolers.

CONCLUSIONS

Atopic asthmatic schoolchildren have greater hyperresponsiveness to methacholine than nonatopics (only among those with normal nutritional status). However, atopic and nonatopic asthmatic preschoolers have similar hyperresponsiveness to methacholine. Therefore, factors different from atopy may be responsible for wheeze in younger children.