Objective: To analyze the prevalence of asthma and asthma symptoms in students of two distinct age brackets residing in the city of Tangará da Serra, Brazil. Methods: Cross-sectional, population-based study of the prevalence of asthma in children from 6 to 7 years of age and adolescents from 13 to 14, using the standardized International Study of Asthma and Allergies in Childhood, phase 1 questionnaire, validated for use in Brazil. Students who responded affirmatively to question 2 (presence of wheezing in the preceding 12 months) were classified as suffering from asthma. Results: The study comprised 3,362 students, of whom 1,634 (48.6%) were children and 1,728 (51.4%) were adolescents. Of the 1,634 children, 816 (49.9%) were male and 818 (50.1%) were female. Of the 1,728 adolescents, 773 (45.0%) were male and 955 (55.0%) were female. The prevalence of asthma among the children was 25.2%, whereas that among the adolescents was 15.9% (χ2 = 8.34; p = 0.00). The children presented higher prevalences of the following symptoms of asthma than did the adolescents: wheezing ever (54.3%), nocturnal dry cough (43.9%), wheezing in the preceding 12 months (25.2%), and from 1 to 3 attacks of wheezing in the preceding 12 months (19.1%). There were no differences between the two groups regarding physician-diagnosed asthma (approximately 4.5%). There were no statistical differences regarding the prevalence of asthma by gender in the two groups. Conclusions: Tangará da Serra has a high prevalence of asthma in children and adolescents, and this result is compatible with other studies carried out in Brazil and Latin America using the same methodology.

Keywords: Asthma/epidemiology; Child; Adolescent.

Objective: To determine the prevalence of asthma among adolescents (13-14 years of age) in the city of Fortaleza, Brazil. Methods: This was a cross-sectional study involving 3,015 adolescents at public and private schools between 2006 and 2007. The participants completed the International Study of Asthma and Allergies in Childhood questionnaire. Results: The prevalences of "wheezing ever", "wheezing within the last 12 months" (active asthma) and "asthma ever" (physician-diagnosed asthma) were 44.1%, 22.6% and 11.6%, respectively. The prevalences of "wheezing ever" (p = 0.001), "1-3 wheezing attacks within the last 12 months" (p = 0.001), active asthma (p = 0.002), "sleep disturbed due to wheezing less than one night per week" (p < 0.001) and "dry cough at night" (p < 0.001) were higher among girls. Private school students presented higher prevalences of "wheezing ever", active asthma, "1-3 wheezing attacks within the last 12 months", "4-12 wheezing attacks within the last 12 months" and physician-diagnosed asthma (p < 0.001 for all), as well as of "exercise-induced wheezing" (p = 0.032). Conclusions: The prevalence of asthma and asthma-related symptoms in students aged 13-14 years in the city of Fortaleza, Brazil, was high, predominantly among girls and private school students. The difference between the prevalence of physician-diagnosed asthma and that of active asthma suggests that asthma was underdiagnosed in the population studied.

Keywords: Asthma/diagnosis; Asthma/epidemiology; Asthma/prevalence.

Background: Asthma is considered the most common chronic childhood disease. However, there have been few studies on the prevalence of asthma in Brazil. Objective: To assess the prevalence and severity of asthma symptoms in school-age children and adolescents living in the city of Duque de Caxias, located in the greater metropolitan area of Rio de Janeiro. Method: Cross-sectional transversal study using the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire. The sample comprised students of 6, 7, 13 and 14 years of age. Results: One group of 2334 students between the ages of 6 and 7 and another composed of 4040 students between the ages of 13 and 14 were evaluated. The prevalence of wheezing within the last 12 months in the younger children was 27.7%, vs. 19% among the adolescents (p < 0.0001). There was a predominance of males in the 6-7 age group (29.9% vs. 25.6%; p = 0.01) and of females in the 13-14 age group (21.9% vs. 15.8%; p < 0.0001). The proportion of previously diagnosed cases of asthma was similar (approximately 10%) for both age brackets. Wheezing upon physical exertion was more prevalent among the adolescents (21.4% vs. 7.8%; p < 0.0001). Symptom severity was higher among female adolescents (severe asthma: 6.6% vs. 4.4%; p = 0.001), although no differences among genders were seen in the 6-7 age group. Conclusion: Asthma prevalence in Duque de Caxias is high, as it is in other Brazilian and Latin American cities. Values are higher in the 6-7 age group, in which symptoms were seen predominantly in males. Among the adolescents, the prevalence and severity of symptoms were higher in females, a recent observation that seems to be a new epidemiological trend of asthma.

Keywords: Key words: Asthma. Epidemiology. Severity of illness index. Cross-sectional studies.

Objective: This study aimed to evaluate the prevalence of developmental defects of enamel (DDEs) in relation to asthma severity, symptom onset and pharmacological treatment in pediatric asthma patients. Methods: Children and adolescents (68 asthma patients and 68 controls), 5-15 years of age and residents of the city of Londrina, Brazil, were enrolled in the study. Medical and dental histories were collected through the use of a structured questionnaire. Each participant underwent a dental examination in which the examiner employed the DDE index. Results: Of the 68 asthma group subjects, 61 (89.7%) presented dental enamel defects, compared with only 26 (38.2%) of those in the control group. Using multivariate logistic regression analysis, we estimated the risk of DDEs in permanent dentition to be 11 times higher in pediatric subjects with asthma than in those without (OR = 11.88, p = 0.0001). The occurrence of dental enamel defects correlated with greater asthma severity (p = 0.0001) and earlier symptom onset (p = 0.0001). However, dental enamel defects did not correlate with the initiation of treatment (p = 0.08) or the frequency of medication use (p = 0.93). Conclusions: Pediatric patients with severe, early-onset asthma are at increased risk of dental enamel defects and therefore require priority dental care.

Keywords: Asthma/prevention & control; Bronchodilator agents; Adrenal cortex hormones/therapeutic use; Dental enamel; Amelogenesis.

Background: Hypersensitivity to dust mites, mold and pet dander found in the home is common among patients with asthma. Home environmental control to reduce exposure to allergens is one of various therapeutic measures that can be taken. Objectives: To determine the prevalence of adequate home environmental control among a study population monitored by the Family Health Program and to identify any possible correlation with the exacerbation of asthma among children between the ages of 5 and 14 in the city of Camaragibe, located in the state of Pernambuco, Brazil. Method: A transversal study was carried out involving 210 mothers/guardians of children, to whom International Study of Asthma and Allergies in Children questionnaires were administered in order to characterize the exacerbation of asthma attacks. The Environment Assessment Guide of Allergic Patients was used to assess the bedrooms and living rooms in the home. Results: Among the 210 asthmatic children and adolescents evaluated in 2001, adequate home environmental control was observed in 141 (67.1%), and no correlation was observed between the degree of environmental control and fewer (< 3) asthma attacks (p = 0.39). Regarding the rooms where the asthmatic patients sleep, inappropriate furnishings were found in the homes of 93 patients (44.3%), including rag curtains in 84 cases (40.2%). Passive smoking was reported in 77 cases (36.7%). Conclusion: The level of home environmental control was satisfactory in the great majority of the residences, which may have contributed to the fact that no correlation was found between home environmental control and lower frequency of acute asthma attacks among the population studied.

Keywords: Key Words: Asthma. Environment Control. Frequency of Attacks.

Background: Asthma is the most common chronic disease among adolescents. Objective: To determine the prevalence of asthma and asthma-related symptoms using the International Study of Asthma and Allergies in Childhood (ISAAC) protocol to evaluate adolescents in the city of Santa Maria, located in the state of Rio Grande do Sul, Brazil. Method: A cross-sectional study evaluating 3066 schoolchildren from 13 to 14 years of age, selected by random sampling, as indicated in the ISAAC protocol. Data were collected from March to June of 2003 using the standardized ISAAC questionnaire, which was completed by the adolescents in the classroom and under the supervision of the researchers. Results: A total of 3066 valid questionnaires (95.5%) were collected. Among the asthma-related symptoms evaluated, the following prevalences were determined: history of wheezing: 42.1%; wheezing within the last 12 months: 16.7%; four or more wheezing attacks within the last 12 months: 1.9%; sleep disturbance on one or more nights a week within the last 12 months: 3.8%; impaired speech within the last 12 months: 3.8%; history of asthma: 14.9%; wheezing after exercise within the last 12 months: 19%; dry cough at night within the last 12 months: 32.4%. Values were significantly higher among females. Conclusion: The prevalence of asthma-related symptoms among adolescents living in the city of Santa Maria was high, predominantly among the females. However, the rate was comparable to the international average and was lower than those observed in larger metropolitan areas in Brazil. These findings underscore the need for regional studies in order to better understand the prevalence of asthma in Brazil.

Keywords: Asthma. Adolescent. Epidemiology.

Objective: To describe the prevalences of asthma and rhinitis in adolescents (13-14 years of age) in the city of Fortaleza, Brazil, in 2010, comparing the results with those obtained in a prevalence survey conducted in 2006-2007. Methods: This was a cross-sectional study involving probabilistic samples of 3,015 and 3,020 adolescents in surveys conducted in 2006-2007 and 2010, respectively. The International Study of Asthma and Allergies in Childhood protocol was used on both occasions. Results: Comparing the two periods, there were no significant differences regarding cumulative wheezing, active asthma, four or more wheezing attacks within the last year, sleep disturbed by wheezing more than one night per week, and speech-limiting wheezing. The prevalences of exercise-induced wheezing, dry cough at night, and physician-diagnosed asthma were significantly higher in 2010 than in the 2006-2007 period (p < 0.01 for all). The prevalence of physician-diagnosed rhinitis was significantly lower in 2010 (p = 0.01), whereas there were no significant differences between the two periods regarding cumulative rhinitis, current rhinitis, and rhinoconjunctivitis. In both periods, dry cough at night, current rhinitis, and rhinoconjunctivitis were significantly more prevalent in females than in males (p < 0.01 for all). Also in both periods, active asthma, current rhinitis, and rhinoconjunctivitis were more prevalent in private school students than in public school students (p < 0.01 for all). Conclusions: Our data show that the prevalences of asthma and rhinitis symptoms remain high among 13- and 14-year-olds in Fortaleza, predominantly among females and private school students.

Keywords: Asthma/epidemiology; Rhinitis/epidemiology; Adolescent.

Objective: To determine the prevalence of emotional and behavioral disorders in adolescents with asthma and to compare it with that of adolescents without asthma. Methods: A transversal study using the Strengths and Difficulties Questionnaire, administered to adolescents with or without asthma, ranging from 14 to 16 years of age and randomly selected from schools in the city of Belo Horizonte, Brazil. Results: The prevalence of emotional and behavioral disorders in adolescents with and without asthma was 20.4% (95% CI: 14.5-27.8%) and 9.0% (95% CI: 6.1-12.8%), respectively. Among adolescents with asthma, 56.6% (95% CI: 48.3-64.5%) presented normal scores, and 23.0% (95% CI 16.8-30.7%) presented borderline scores. Among adolescents without asthma, 75.0% (95% CI: 69.7-79.6%) presented normal scores, and 16.0% (95% CI: 12.2-20.7%) presented borderline scores. The median total score on the questionnaire was 14 and 12 among subjects with and without asthma, respectively (p < 0.01). In the final logistic regression model, adjusted for socioeconomic variables, the association between emotional/behavioral disorders and the following variables remained significant: being female (OR = 1.98; 95% CI: 1.10-3.56; p = 0.02) and having asthma (OR = 2.66; 95% CI: 1.52-4.64; p = 0.001). Conclusions: The prevalence of emotional and behavioral disorders is higher in adolescents with asthma than in those without asthma, underscoring the need for a holistic, interdisciplinary approach.

Keywords: Asthma; Epidemiology; Prevalence; Adolescent; Psychology; Behavioral symptoms.

Objective: To analyze the role that low income plays in the development of asthma in children and adolescents. Methods: A case-control study using a questionnaire. Results: A total of 687 participants were studied at a tertiary hospital via the Brazilian Unified Health System. Ages ranged from 5 to 15 years, and 54.7% of the participants were male. Nearly half of the individuals (49.1%) lived in the metropolitan area of the city of Recife, and the remainder lived in the countryside. Most (98.1%) lived in concrete houses or apartments, with a mean of 5.7 rooms and 4.8 occupants per residence. Mean maternal level of education was 6.8 years of schooling. The median monthly per capita income was R$ 103.75 (Brazilian reals). The sample was stratified according to cut-off points related to the national minimum wage (R$ 350.00): <25% of minimum wage = very low income (39% of the sample); <50% of minimum wage = low income (37.3% of the sample); and ≥50% of minimum wage = satisfactory income (23.7% of the sample). There was no association between poverty and development of asthma. Conclusions: Poverty is not protective against asthma in children and adolescents treated via the Brazilian Unified Health System, as we might suppose based on the hygiene hypothesis. However, cohort studies are needed in order to confirm these findings.

Keywords: Asthma; Poverty; National health programs/Brazil; Child; Adolescent; Case-control studies.

Objective: To determine, through home visits, the rate of compliance with environmental control measures in the homes of children with asthma. Methods: This study involved 98 asthma patients between the ages of 4 and 15. The parents of those children and adolescents received instruction in how to carry out environmental control measures and were encouraged to perform such measures continuously for a period of 90 days. Home visits, which included direct inspection of the domicile and administration of a questionnaire, were made before and after this 90-day period. In cases of noncompliance, parents were asked to explain why they did not carry out the control measures. Statistical analysis was performed using the McNemar test. Results: Overall compliance with the various items studied was 11.1%, ranging from -4.1% (for curtain control, p = 0.63) to 22.6% (for stuffed toys, p < 0.001). Passive smoking was reduced to 9.7% (p = 0.02). Among the families studied, the mean monthly income was 2.5 times the national minimum wage. When asked why they had not adopted the recommended measures, noncompliant parents gave, among others, the following explanations: "economic hardship" (60.1%); "the measures were too difficult to carry out" (6.1%); "nonparticipation of the father" (4%); and "lack of time on the part of the mother" (4%). Conclusion: Environmental control measures were carried out sporadically, possibly reflecting the influence of socioeconomic and cultural factors.

Keywords: Asthma; Allergens; Environmental exposure; Hypersensivity/prevention & control; Compliance

To evaluate the characteristics of users of inhalers and the frequency of inhaler use among adolescents and adults with self-reported physician-diagnosed asthma, bronchitis, or emphysema. Methods: A population-based study conducted in the city of Pelotas, Brazil, involving 3,670 subjects ≥ 10 years of age, evaluated with a questionnaire. Results: Approximately 10% of the sample reported at least one of the respiratory diseases studied. Among those individuals, 59% reported respiratory symptoms in the last year, and, of those, only half reported using inhalers. The use of inhalers differed significantly by socioeconomic status (39% and 61% for the lowest and the highest, respectively, p = 0.01). The frequency of inhaler use did not differ by gender or age. Among the individuals reporting emphysema and inhaler use, the use of the bronchodilator-corticosteroid combination was more common than was that of a bronchodilator alone. Only among the individuals reporting physician-diagnosed asthma and current symptoms was the proportion of inhaler users higher than 50%. Conclusions: In our sample, inhalers were underutilized, and the type of medication used by the individuals who reported emphysema does not seem to be in accordance with the consensus recommendations.

Keywords: Metered dose inhalers; Asthma; Pulmonary disease, chronic obstructive; Bronchitis; Emphysema; Dry powder inhalers.

Objective: To evaluate the association between asthma prevalence and serum levels of vitamin D in Brazilian adolescents. Methods: This was a cross-sectional, school-based study involving adolescents between 12-17 years of age from four large Brazilian cities located at different latitudes (Fortaleza, Rio de Janeiro, Brasília, and Porto Alegre). Information on asthma diagnosis, lifestyle, and sociodemographic characteristics was collected by means of self-administered questionnaires. Serum concentrations of calcifediol were dichotomized as sufficient (= 20 ng/mL) or insufficient/deficient (< 20 ng/mL) levels. Bivariate analyses were carried out between vitamin D levels and prevalence of active asthma (AA), as well as other variables in study, using the chi-square test. Generalized linear models were configured to analyze potential confounding factors (p < 0.20). Results: Between 2013 and 2014, 1,053 adolescents were evaluated. The prevalences of AA and insufficient/deficient levels of calcifediol were 15.4% and 21%, respectively. There were no statistically significant associations between AA and hypovitaminosis D. The prevalences of AA and vitamin D insufficiency were, respectively, 2.34 (95% CI, 1,28-4.30) and 3.22 (95% CI, 1.75-5.95) times higher in Porto Alegre than in Rio de Janeiro, regardless of possible confounding factors. However, no significant associations were found between the prevalence of AA and vitamin-D-related variables in any of the cities. Conclusions: No association was found between AA and low levels of vitamin D in adolescents living at different latitudes in Brazil.

Keywords: Adolescent; Asthma/epidemiology; Vitamin D.

Background: In recent decades, the prevalence of asthma has increased. Objectives: To determine the prevalence of asthma symptoms in children and adolescents from 2 to 14 years of age living in Porto Alegre (in the state of Rio Grande do Sul, Brazil) and to determine any potential correlations with socioeconomic profile, treatment and smoking in the home. Methods: A transversal study based on interviews of all families seeking medical attention in June of 2000. Results: The prevalence of asthma symptoms was 49.5%. In 66.8% of families, total income was less than four times the minimum wage, and in more than 50% of homes, the parents had had less than five years of schooling. In 98.5%, prophylactic asthma treatment was not used. In the 174 families studied, 38.7% of mothers and 43.7% of fathers were smokers (32.7% overall). Correlations were found between the following variables: exposure to smoking in the home and number of asthma attacks in the last year (p = 0.02; RR = 2.9; CI: 1.1 - 4.5); maternal level of education and number of attacks in the last year (p = 0.03; RR = 2.03; CI: 1.01 - 4.19); close living quarters and number of attacks in the last year among children exposed to second-hand smoke (p = 0.04; RR = 2.7; CI: 1.4 - 5.1); hospitalization and number of attacks in the last year (p = 0.004; RR = 1.46; CI: 1.15 -1.86); hospitalization and close living quarters (p = 0.03; RR = 1.47; CI: 1.15 -1.86). In children below the age of five, there was correlation between maternal smoking and number of attacks in the last year (p = 0.03; RR = 1.79; CI: 1.04 - 3.08). Conclusion: The prevalence of asthma symptoms was high. The community studied has limited socioeconomic resources, and there is therefore a lack of adequate treatment for asthma. Our results demonstrate the need for prioritized, standardized treatment programs that would give healthcare workers access to the appropriate materials and means of evaluation necessary for asthma control.

Keywords: Key words: Asthma. Prevalence. Smoking in the home. Treatment between episodes of asthma.

Objective: To estimate the prevalence of obstructive sleep apnea syndrome (OSAS) in children and adolescents with sickle cell anemia (SCA); to investigate the possible correlation between mean annual hemoglobin level and total sleep time with SpO2 < 90%, as well as between mean annual hemoglobin level and total sleep time with SpO2 < 80%; and to investigate the possible correlation between apnea-hypopnea index (AHI) and painful crisis. Methods: The study involved 85 patients with SCA. The patients completed a questionnaire, were submitted to polysomnography and underwent clinical evaluation (by a pediatrician and an otolaryngologist). An AHI > 1 was considered indicative of a diagnosis of OSAS. Results: The prevalence of OSAS was 10.6%. We found a negative correlation between mean annual hemoglobin level and total sleep time with SpO2 < 90% (r = −0.343; p = 0.002), as well as between mean annual hemoglobin level and total sleep time with SpO2 < 80% (r = −0.270; p = 0.016). There was no association between AHI and painful crisis. Conclusions: The prevalence of OSAS in this population was high (10.6%). Therefore, it is important to identify signs of OSAS as soon as possible and to determine the mean annual hemoglobin level because of the inverse correlation between that level and the total sleep time with SpO2 < 90% or < 80%.

Keywords: Prevalence; Sleep apnea, obstructive; Anemia, sickle cell; Polysomnography; Sleep apnea syndromes.

Objective: To determine whether polymorphisms of the IL10 and IL17 genes are associated with severe asthma control and bronchodilator reversibility in children and adolescents with severe asthma. Methods: This was a cross-sectional study, nested within a prospective cohort study of patients with severe asthma. Two outcomes were evaluated: asthma control and bronchodilator reversibility. We extracted DNA from peripheral blood and genotyped three single nucleotide polymorphisms: rs3819024 and rs2275913 in the IL17A gene; and rs3024498 in the IL10 gene. For the association analyses, we performed logistic regression in three genetic models (allelic, additive, and dominant). Results: The rs3024498 C allele in the IL10 gene was associated with failure to achieve asthma control despite regular treatment (p = 0.02). However, the G allele of the IL17A rs3819024 polymorphism was associated with failure to respond to stimulation with a ß2 agonist. The rs2275913 polymorphism of the IL17A gene showed no relationship with asthma control or bronchodilator reversibility. Conclusions: In pediatric patients with severe asthma, the IL10 polymorphism appears to be associated with failure to achieve clinical control, whereas the IL17A polymorphism appears to be associated with a worse bronchodilator response. Knowledge of the involvement of these polymorphisms opens future directions for pharmacogenetic studies and for the implementation of individualized therapeutic management of severe asthma in pediatric patients.

Keywords: Polymorphism, genetic; Interleukin-10; Interleukin-17; Asthma.

Objective: To evaluate quality of life according to the level of asthma control and degree of asthma severity in children and adolescents. Methods: We selected children and adolescents with asthma (7-17 years of age) from the Pediatric Pulmonology Outpatient Clinic of the State University of Campinas Hospital de Clínicas, located in the city of Campinas, Brazil. Asthma control and asthma severity were assessed by the Asthma Control Test and by the questionnaire based on the Global Initiative for Asthma, respectively. The patients also completed the Paediatric Asthma Quality of Life Questionnaire (PAQLQ), validated for use in Brazil, in order to evaluate their quality of life. Results: The mean age of the patients was 11.22 ± 2.91 years, with a median of 11.20 (7.00-17.60) years. We selected 100 patients, of whom 27, 33, and 40 were classified as having controlled asthma (CA), partially controlled asthma (PCA), and uncontrolled asthma (UA), respectively. As for asthma severity, 34, 19, and 47 were classified as having mild asthma (MiA), moderate asthma (MoA), and severe asthma (SA), respectively. The CA and the PCA groups, when compared with the NCA group, showed higher values for the overall PAQLQ score and all PAQLQ domains (activity limitation, symptoms, and emotional function; p < 0.001 for all). The MiA group showed higher scores for all of the PAQLQ components than did the MoA and SA groups. Conclusions: Quality of life appears to be directly related to asthma control and asthma severity in children and adolescents, being better when asthma is well controlled and asthma severity is lower.

Keywords: Asthma; Quality of life; Child; Adolescent.

Objective: To describe the clinical, radiological and endoscopic characteristics of foreign body aspiration among individuals under the age of 15 treated at a referral center in the city of São Luís, Brazil. Methods: This was a descriptive study using data from the medical charts of patients treated for foreign body aspiration at the Hospital Universitário Materno Infantil between 1995 and 2005. We investigated 72 confirmed cases of foreign body aspiration, evaluating the place of residence, as well as biological, clinical, radiological and endoscopic variables. We used the chi-square test to identify statistically significant differences in frequency among the variables studied. Results: The majority of the patients were from outlying areas (55.6%). The following variables presented the highest frequencies: 0-3 year age bracket (81.9%); male gender (63.9%); evolution > 24 h (66.7%); hypotransparency on chest X-ray (57.7%); foreign body in the right lung (41.2%) or in the larynx (20.5%); organic nature of the foreign body (83.3%); complication in the form of localized inflammation (59.4%); glottal edema as an endoscopic complication (47.6%); and seeds (46.6%), fish bone (28.3%) or plastics (25.5%) as the type of foreign body. There were no deaths. Conclusions: Preventive care should be a priority for male children under the age of 3 living in outlying areas. Such children should not be given access to substances that can be aspirated, including certain foodstuffs. Simple and easily accessible radiological tests have been underused, which jeopardizes the quality of the initial treatment.

Keywords: Foreign bodies; Inhalation; Bronchoscopy.

Objective: Asthma is the most common chronic pulmonary disease, characterized by bronchial inflammation. Some children with asthma have persistent pulmonary function impairment. The prevalence and etiology of this abnormality in children with asthma in developing countries remain unknown. The objective of this study was to estimate the proportion of patients with impaired pulmonary function who were unresponsive to treatment in a group of children and adolescents with asthma, and to describe the phenotypic characteristics of the sample. Methods: Using a standardized questionnaire, we selected outpatients (5-17 years of age) diagnosed with persistent asthma. These patients underwent spirometry and skin prick tests for sensitivity to common aeroallergens. Persistent pulmonary function impairment was defined as an FEV1/FVC ratio < 0.80, even after 10 days of treatment with bronchodilators and oral corticosteroids. We used the atopic index to differentiate between patients with little or no response to the skin prick test and those with a strong response (cut-off point: 4 allergens). Results: We included 96 patients with a mean age of 10.6 years. Of those, 52 (54.1%) were male, and 89 (92.7%) were atopic. Of the 96 patients, 8 (8.3%) had impaired pulmonary function even after the treatment. Among those patients, 8 (100%) were atopic, 7 (87.5%) had moderate or severe asthma, and 7 (87.5%) had a history of hospitalization for acute bronchiolitis. Conclusions: Children and adolescents with moderate or severe asthma can present with impaired pulmonary function and be unresponsive to treatment. This clinical situation has been little studied in developing countries, and its risk factors and etiology will be better understood only through birth cohort studies.

Keywords: Asthma; Respiratory function tests; Allergy and immunology.