Microdeletion 22q11.2 syndrome: Does thymus incidental surgical resection affect its immunological profile?

BACKGROUND: The del22q11 syndrome patients present immunological abnormalities associated to thymus alterations. Up to 75% of them present cardiopathies and thymus is frequently removed during surgery. The thymectomy per se has a deleterious effect concerning lymphocyte subpopulations, and T cell function. When compared to healthy controls, these patients have higher infections propensity of variable severity. The factors behind these variations are unknown. We compared immunological profiles of del22q11.2 Syndrome patients with and without thymectomy to establish its effect in the immune profile. METHODS: Forty-six del22q11.2 syndrome patients from 1 to 16 years old, 19 of them with partial or total thymectomy were included. Heart disease type, heart surgery, infections events and thymus resection were identified. Immunoglobulin levels, flow cytometry for lymphocytes subpopulations and TREC levels were determined, and statistical analyses were performed. RESULTS: The thymectomy group had a lower lymphocyte index, both regarding total cell count and when comparing age-adjusted Z scores. Also, CD3+, CD4+ and CD8+ lower levels were observed in this group, the lowest count in those patients who had undergone thymus resection during the first year of life. Their TREC level median was 23.6/µL vs 16.1µL in the non-thymus group (p=0.22). No differences were identified regarding immunoglobulin levels or infection events frequencies over the previous year. CONCLUSION: Patients with del22q11.2 syndrome subjected to thymus resection present lower lymphocyte and TREC indexes when compared to patients without thymectomy. This situation may be influenced by the age at the surgery and the time elapsed since the procedure.

Fungal Allergy: Pattern of sensitization over the past 11 years.

INTRODUCTION AND OBJECTIVES: Although the prevalence of sensitization to fungi is not precisely known, it can reach 50% in inner cities and has been identified as a risk factor in the development of asthma. Whereas the prevalence of allergic diseases is increasing, it is unclear whether the same occurs with sensitization to fungi. PATIENTS AND METHODS: A retrospective study was performed at the "Hospital Infantil de México Federico Gómez". From skin tests taken between 2004 and 2015, information was gathered about Alternaria alternata, Aspergillus fumigatus, Candida albicans, Cladosporium herbarum, Mucor mucedo and Penicillium notatum. The participating patients were 2-18 years old, presented some type of allergic condition, and underwent immediate hypersensitivity tests to the fungi herein examined. Descriptive analysis and chi-squared distribution were used. RESULTS: Of the 8794 patients included in the study, 14% showed a negative result to the entire panel of environmental allergens. The remaining 7565 individuals displayed sensitization to at least one fungus, which most frequently was Aspergillus, with a rate of 16.8%. When the patients were divided into age groups, the same trend was observed. The highest percentage of sensitization (58%) toward at least one type of fungus was found in 2014, and the lowest percentage (49.8%) in 2008. CONCLUSION: The rate of sensitization to at least one type of fungus was presently over 50%, higher than that detected in other medical centers in Mexico. This rate was constant over the 11-year study, and Aspergillus exhibited the greatest frequency of sensitization among the patients.

Cross-over clinical trial for evaluating the safety of camel's milk intake in patients who are allergic to cow's milk protein.

BACKGROUND: Cow's milk protein allergy (CMPA) affects between 0.6 and 0.9% of the general population, and its treatment implies the total elimination of the intake of this protein. Camel's milk has been suggested as an alternative for patients over one year of age who suffer from CMPA due to the difference in the amino acid sequence from that of cow's milk. The objective of this study was to evaluate the safety and tolerability of camel's milk in children with CMPA. METHODS: Crossed clinical trial for the use of camel's milk vs. amino acid formula, carried out at the Dr. Federico Gómez Children's Hospital of Mexico (HIMFG) on patients between one and 18 years of age with diagnosed CMPA confirmed through double-blind, placebo-controlled food challenges (DBPCFCs). Only those whose allergies were confirmed were randomly placed into two groups: those to be administered camel's milk and those to be administered the amino-acid formula for two weeks, followed by a six-week wash-out period, and then a group crossing for a further two weeks. RESULTS: 49 patients with suspected CMPA were included in the study; the diagnosis was confirmed through DBPCFCs in 15 patients, who were those who participated in the study. After having been administered camel's milk, none of the patients presented adverse effects. CONCLUSIONS AND CLINICAL RELEVANCE: Camel's milk is safe and tolerable in patients above one year of age with CMPA and can be considered as a good alternative given the benefit of its taste compared to other formulas.

Dermatophagoides pteronyssinus: Changes in sensitisation in the past 11 years and comparison with other centres in Mexico.

BACKGROUND: House dust mites are a ubiquitous air allergen in the human habitat. It has been shown that exposure to them is a fundamental factor in sensitisation and development of atopic disease. The objective of the study was to analyse changes in sensitisation to Dermatophagoides pteronyssinus (Der p.) in children treated in a tertiary level care hospital in Mexico City for a period of 11 years and compare with other studies carried out in Mexico. METHODS: A retrospective study was performed at the Hospital Infantil de México Federico Gómez (HIMFG). Information was gathered from skin tests for Der p. performed in the Allergy Laboratory from January 2004 to April 2015. Patients 2-18 years old who presented for examination of some type of allergic condition and who had immediate hypersensitivity tests to Der p. were included in the study. Results were compared with prior reports from other institutions. Descriptive analysis and χ2 statistics were used. RESULTS: A total of 8794 patients were included in the study; 49.3% of the tests (95% CI 48-50) were positive for Der p. The percentage of monosensitised to mites was 2.7% for Der p. (95% CI 2-3). A significant difference was found between the results of older patients and those <6 years old. The frequency of sensitisation had a tendency to decrease during the 11 years analysed in all age groups. CONCLUSIONS AND CLINICAL RELEVANCE: The frequency of sensitisation to Der p. increased with age until reaching adolescence. In the last 11 years a decrease in sensitisation to this air allergen was observed.

Elemental carbon exposure and lung function in school children from Mexico City.

Though exposure to air pollution has a detrimental effect on respiratory health, few studies have examined the association between elemental carbon exposure and lung function among schoolchildren. The aim of the present study was to present the association between short-term elemental carbon exposure and lung function in schoolchildren from Mexico City. 55 asthmatic and 40 non-asthmatic children were followed for an average of 22 weeks. A spirometry test was performed every 15 days during follow-up. Portable air samplers collected particulate matter onto Teflon filters. Gravimetric analysis was conducted and elemental carbon was quantified using transmission densitometry. The association between the main variables was analysed using linear mixed effects models. The mean ± sd of elemental carbon light absorption was 92.7 ± 54.7 Mm(-1). An increase of one interquartile range in the 24-h average of elemental carbon (100.93 Mm(-1)) was associated with a significant negative impact on forced expiratory volume in 1 s (FEV(1)) (-62.0 (95% CI -123.3- -1.2) mL) and forced expiratory flow at 25-75% of forced vital capacity (FVC) (FEF(25-75%)) (-111 (95% CI -228.3- -4.1) mL) among asthmatic children, equal to 3.3% and 5.5%, respectively; and on FEV(1) (-95.0 (95% CI -182.3- -8.5) mL) and FVC (-105.0 (95% CI -197.0- -13.7) mL) among non-asthmatic children. Exposure to elemental carbon resulted in an important negative effect on lung function in atopic schoolchildren, regardless of asthma status.

Weight loss induced by 6-month lifestyle intervention improves early endothelial activation and fibrinolysis in obese adolescents.

BACKGROUND: Adolescent obesity is associated with an increased risk of adult obesity and subsequent cardiovascular diseases. The present study aimed to assess the effect of weight loss after 6-month lifestyle intervention in obese adolescents on biomarkers of endothelial activation and fibrinolytic system. METHODS: Eighty-five obese adolescents aged 10 to 16 years were assigned to a 6-month lifestyle intervention and 61 completed the programme. We examined the effect of the intervention on adhesion molecules (selectin E, soluble intercellular adhesion molecule 1 and soluble vascular adhesion molecule 1) and fibrinolytic parameters [plasminogen activator inhibitor-1 (PAI-1) and fibrinogen]. Thirty-six lean adolescents were studied only at baseline as a comparison group. RESULTS: Compared with lean participants, obese adolescents at baseline demonstrated significantly higher levels of triglycerides, glucose, insulin, homeostasis model assessment, soluble intercellular adhesion molecule 1, PAI-1 and fibrinogen. After 6-month lifestyle intervention, those obese adolescents with decreased standard deviation score-body mass index (SDS-BMI) displayed significant decreases in insulin (19.2 ± 11.2 vs. 26.8 ± 13.2 mU/L, P≤ 0.01), homeostasis model assessment (4.24 ± 3.19 vs. 6.58 ± 4.08, P≤ 0.01), selectin E (100.2 ± 60.9 vs. 116.0 ± 69.0 ng/mL, P≤ 0.01) and PAI-1 (39.6 ± 38.0 vs. 51.8 ± 25.6 ng/mL, P≤ 0.05) with respect to the baseline levels. No changes in these parameters were observed in the obese adolescents with stable or increased SDS-BMI. The changes of triglycerides after intervention in subgroup with decreased SDS-BMI were significantly greater than those in subgroup with stable SDS-BMI. CONCLUSIONS: The present study demonstrated increased endothelial activation and impairment of the fibrinolytic system in early life, which is in part reversible by a 6-month lifestyle intervention.

Genetic variation in ORM1-like 3 (ORMDL3) and gasdermin-like (GSDML) and childhood asthma.

BACKGROUND: A genome-wide association study identified ORM1-like 3 (orosomucoid 1-like 3, ORMDL3) as an asthma candidate gene. Single nucleotide polymorphisms (SNPs) in the region including ORMDL3 on chromosome 17q21 were related to childhood asthma risk and ORMDL3 expression levels in Europeans. OBJECTIVE: We examined whether polymorphisms in ORMDL3 and the adjacent gasdermin-like (GSDML) gene associated with asthma in the genome-wide association study are related to childhood asthma and atopy in a Mexico City population. METHODS: We genotyped rs4378650 in ORMDL3 and rs7216389 in GSDML in 615 nuclear families consisting of asthmatic children aged 4-17 years and their parents. Atopy was determined by skin prick tests to 25 aeroallergens. RESULTS: Individuals carrying the C allele of rs4378650 or the T allele of rs7216389 had increased risk of asthma [relative risk (RR) = 1.73, 95% confidence interval (CI) 1.19-2.53, P = 0.003 for one or two copies of rs4378650 C, and RR = 1.64, 95% CI 1.12-2.38, P = 0.009 for one or two copies of rs7216389 T). Linkage disequilibrium between the two SNPs was high (r(2) = 0.92). Neither of the SNPs was associated with the degree of atopy. A meta-analysis of five published studies on rs7216389 in nine populations gave an odds ratio for asthma of 1.44 (95% CI, 1.35-1.54, P < 0.00001). CONCLUSIONS: Our results and the meta-analysis provide evidence to confirm the finding from a recent genome-wide association study that polymorphisms in ORMDL3 and the adjacent GSDML may contribute to childhood asthma.

Lack of association between genetic variation in G-protein-coupled receptor for asthma susceptibility and childhood asthma and atopy.

G-protein-coupled receptor for asthma susceptibility (GPRA or GPR154) was identified as an asthma and atopy candidate gene by positional cloning. Some subsequent studies suggest associations of GPRA single nucleotide polymorphisms (SNPs) and haplotypes with asthma or atopy susceptibility. However, the associated SNPs or haplotypes vary among studies. The role of GPRA genetic variation in asthma and atopy remains unsolved. Published data on GRPA variants and asthma come exclusively from Caucasian and Asian populations. We examined whether GPRA SNPs and haplotypes are associated with asthma and atopy in a Mexican population. We genotyped and analyzed 27 GPRA SNPs in 589 nuclear families consisting of asthmatic children aged 4-17 years of age and their parents in Mexico City. Atopy was determined by skin prick tests to 25 aeroallergens. The 27 SNPs examined provided excellent coverage of the GPRA gene. GPRA SNPs and haplotypes were not associated with childhood asthma and the degree of atopy to aeroallergens in a Mexican population. Our review of studies of GPRA variants in relation to asthma phenotypes shows considerable heterogeneity. Accordingly, our results suggest that GPRA variants are not an important contributor to childhood asthma and atopy susceptibility in a Mexican population.

Study of the relationship between acetaminophen and asthma in Mexican children aged 6 to 7 years in 3 Mexican cities using ISAAC methodology.

OBJECTIVE: To establish the relationship between the use of acetaminophen and the frequency of asthma in Mexican children in 3 Mexican cities. METHODS: Ours was a multicenter, observational, descriptive, cross-sectional study. Patients from 6 to 7 years of age participating in Phase Three B of the ISAAC (International Study of Asthma and Allergies in Children) living in the north of Mexico City, Victoria City, and Merida were included. After adjusting for confounders, we calculated the odds ratios (OR) for the presence of wheezing ever, wheezing in the last 12 months, asthma ever, and the use of acetaminophen in the first year of life and during the last 12 months. RESULTS: The ORs for wheezing ever, wheezing in the last year, and asthma ever with respect to use of acetaminophen in the first year of life were not statistically significant (P > .05) in Mexico City, but they were significant in Victoria City (P < .05) and Merida (P < .05). The ORs (95% confidence intervals) for wheezing ever, wheezing in the last year, and asthma ever with respect to use of acetaminophen in the last year were 3.44 (2.96-4.0), 7.97 (5.89-10.78), and 6.10 (3.30-8.81) (P < .05) in Mexico City. Values forVictoria City were 1.36 (1.13-1.63), 3.80 (2.88-5.05), and 2.18(1.57-3.01) (P < .05). Those for Merida were 1.61 (1.40-1.85), 2.07 (1.73-2.48), and 1.53 (1.29-1.82) (P < .05). CONCLUSION: The use of acetaminophen is associated with the presence of wheezing and asthma in 3 different cities in Mexico.

Factors associated with allergic rhinitis in children from northern Mexico City.

BACKGROUND: The International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire allows users to find factors associated with allergic diseases, but thus far most of the studies on risk factors for allergic diseases have been devoted to asthma and not to rhinitis. OBJECTIVE: To determine the main factors associated with symptoms of allergic rhinitis and rhinoconjunctivitis in school children and adolescents in northern Mexico City. PATIENTS AND METHODS: A cross sectional, multicenter survey was conducted in northern Mexico City, in children aged 6-7 and 13-14 years. The survey instrument was the Phase Three B ISAAC questionnaire, which was validated and standardized in Spanish. RESULTS: There were 4106 6-7-year-olds and 6576 13-14-year-olds. The total prevalence of diagnosis of allergic rhinitis was 4.6%. The prevalence of cumulative and current symptoms of rhinitis was considered high (>29%), but the prevalence of the diagnosis of allergic rhinitis was considered low (ranging from 3.4% to 5.6%). The prevalence of symptoms of rhinitis with conjunctivitis had intermediate values (ranging from 20.3% to 30.2%). Cumulative symptoms of allergic rhinitis, current symptoms of allergic rhinitis, and rhinoconjunctivitis were related to symptoms of current or cumulative asthma, symptoms of current or cumulative atopic eczema, and current use of paracetamol (odds ratio > 1, P < .05). CONCLUSION: The present results support the concept of rhinitis and asthma as common chronic respiratory diseases, and this study also found a relation between paracetamol use and rhinitis in children.

Immunostimulants for preventing respiratory tract infection in children.

BACKGROUND: Acute respiratory tract infections (ARTIs) are a major cause of childhood morbidity and mortality. Immunostimulants (IS) may reduce the incidence of ARTIs. OBJECTIVES: To determine the efficacy and safety of IS in preventing ARTIs in children. SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 4, 2005); MEDLINE (January 1966 to January 2006); and EMBASE (January 1990 to January 2006); PASCAL (up to January 2006); SciSearch (up to January 2006); and IPA (up to January 2006) for reports of trials. Investigators in the field were also contacted. Ongoing studies were searched in the trial registration web site, metaRegister of Controlled Trials. SELECTION CRITERIA: All comparative trials which enrolled patients less than 18 years of age were included. The intervention of interest was the use of an IS medication administered by any method for preventing ARTIs. Clinical trials using random or quasi-random allocation and comparing IS medication or medications to placebo were included. DATA COLLECTION AND ANALYSIS: The outcome on ARTIs was analyzed both as the mean number of ARTIs by group and as a percent change in the rate of ARTIs. Meta-analysis was undertaken using a random-effects model and results were presented as weighted mean differences (WMD) with 95% confidence intervals (CI). The trials search, quality assessment and data extraction were undertaken independently by two authors. A funnel plot suggested there may be publication bias in the trials identified. MAIN RESULTS: Thirty-four placebo controlled trials (3877 participants) provided data in a form suitable for inclusion in the meta-analysis. When compared with placebo, the use of IS was shown to reduce ARTIs measured as the total numbers of ARTIs (WMD -1.27; 95% CI -1.58 to -0.97) and the difference in ARTIs rates (WMD -39.68%; 95% CI -47.27% to -32.09%). The trial quality was generally poor and a high level of statistical heterogeneity was evident. The subgroup analysis of bacterial IS studies produced similar results, with lower heterogeneity. No difference in adverse events was evident between the placebo and IS groups AUTHORS' CONCLUSIONS: This review showed that IS reduces the incidence of ARTIs in children, by 40% on average. However, due to significant heterogeneity and the poor quality of the trials this positive result should be interpreted with caution. The safety profile of IS appears to be good. Further high-quality trials are needed and we encourage national health authorities to conduct large, multicenter, double-blind, placebo-controlled trials on the role of IS in the prevention of ARTIs.

Efficacy and safety of mepyramine-theophylline-acetate in the treatment of asthmatic crisis in children.

Mepyramine-theophylline-acetate (MTA), a theophylline derivative combined with an antihistamine, is used to treat patients with asthma. A double-blind, randomized, prospective, parallel-group study was conducted to evaluate the efficacy and safety of MTA in the treatment of asthmatic crisis in children 2 to 6 years of age. Forty patients with mild-to-moderate asthma were admitted to the study. The MTA group received 8 mg/kg per day of MTA by mouth in three divided doses for 7 days. The other group received 50 microL/kg per day of placebo in three divided doses for 7 days. Salbutamol (albuterol) syrup was used as the rescue drug if manifestations of asthma persisted. Both the MTA group and the placebo group had similar demographic characteristics at baseline. Both groups showed improvement of the asthma symptoms (cough, dyspnea, hypoventilation, and wheezing), as evaluated by the investigators at days 3 and 7. Patient diary scores showed earlier improvements in the MTA group than in the placebo group. Both groups showed improvement in peak flow at days 3 and 7 (P = 0.005). The control group used more doses of salbutamol than the MTA group on days 2 through 6 and globally (mean +/- SD, 6.79 +/- 9.11 doses vs 1.29 +/- 2.23 doses). The improvements in the placebo group were thought to be due to salbutamol. Three MTA patients dropped out of the trial, one because the parents felt that the treatment was not effective and two because of gastrointestinal manifestations (epigastric discomfort and vomiting). In the placebo group, two patients dropped out. One patient had epigastric discomfort and the other had to be treated in the emergency department for an exacerbation of the asthma. We conclude that MTA may be a good therapeutic option for the treatment of asthmatic crisis in children 2 to 6 years of age.

The relationship between asthma symptoms and anthropometric markers of overweight in a Hispanic population.

BACKGROUND: Previous studies have revealed the relationship between asthma and obesity, but the relationship with other markers of overweight and obesity has not yet been investigated. OBJECTIVE: To establish the relationship between asthma symptoms and simple anthropometric indexes (BMI, waist circumference (WC), and waist-to-hip ratio (WHR)) as markers of overweight in an adult Hispanic population. METHODS: The data were obtained from the PRIT (Prevalence of Cardiovascular Risks in General Hospital Workers) 2001 survey. The participants were workers at the Hospital General de México in Mexico City and included 135 men and 398 women aged 43.8 +/- 11.9 and 43.0 +/- 10.5, respectively. Odds ratios for asthma symptoms at different BMI, WC, and WHR cutoff points associated with excessive weight were calculated. The likelihood ratios for having asthma symptoms in participants with various cutoff values of BMI, WC, and WHR also were calculated. RESULTS: Asthma symptoms were not related to anthropometric markers of overweight or obesity in men, while they were associated in women with WC cutoff levels of 80 and 85 cm, and BMI of 25 and 27 kg/m2. No level of WHR was related to asthma symptoms in women. In women, the likelihood ratio for asthma symptoms increased proportionally from WC levels of 73.5 cm up to 86 cm, while this risk increased significantly from BMI levels of 22 up to 29 kg/m2. CONCLUSION: Overweight as assessed by BMI and WC (but not WHR) was related to asthma symptoms in women in the studied population.

Clinical evaluation of tulobuterol aerosol in childhood asthma.

An open clinical trial was performed to assess the efficacy and safety of 400 micrograms tulobuterol aerosol given four times daily in childhood bronchial asthma. A total of 54 children were enrolled with bronchial asthma shown to be reversible by an increase of forced expiratory volume in 1 s (FEV1) of more than 15% following 200 micrograms of salbutamol. Tulobuterol was administered for 3 weeks and regular use of salbutamol was continued for 12 patients during the 7-day lead-in period and six patients took theophylline throughout the study; other drugs were discontinued. The mean FEV1, mean adjusted FEV1, mean peak expiratory flow rate (PEFR) and mean forced vital capacity (FVC) were significantly increased (P less than 0.001) following treatment. Mean FEV1 increases ranged from 9.2% to 14.0%, with 24.5-43.4% of patients showing clinically significant increases of at least 15%. Globally, there was improvement in 46 patients (85%). Headache and nervous system complaints were the most common side-effects. Although this was an uncontrolled study, the indications are that tulobuterol aerosol is effective and safe for use in children with asthma.

[Asthma and pregnancy]. / Asma y embarazo.

Asthma is among the diseases that may complicate pregnancy. Asthma affects up to 4% of the pregnant women. Uncontrolled asthma may impair the proper oxygenation of both mother and child. According to asthma severity clinical manifestations may be unapparent or apparent requiring hospital treatment. It is necessary that pregnant asthmatic woman check daily the peak-flow by portable peak-flow meters. The asthma pharmacological treatment should consider the changes in the physiology of the pregnancy, such as low albumin and carrier proteins for the drugs inducing high levels of free active drugs. This point is important for theophylline, besides the low drug clearance. Bronchodilator should be used as they are required, using the inhaled forms, as well as short term corticoid courses. The goal of the treatment is to control the symptoms, avoid relapse and keep the ventilatory function close to the normal, in order to achieve a satisfactory state of the mother and the children.

[Epidemiologic aspects of childhood asthma in Mexico. Asthma in the Child Study Group]. / Aspectos epidemiológicos del asma infantil en México. Groupo de Estudio del Asma en el Ninõ.

Asthma is one of the most frequent chronic diseases in children. Its epidemiological tendency is of great importance. In this study, we evaluated the statistical information available from 1987 to 1994 on childhood asthma from several medical institutions in Mexico. We found that: 1) the frequency of medical care provided to asthmatic children under the age of 15 in outpatient, emergency and within hospital settings, expressed as a percentage of the total care provided for each category, has remained unchanged in almost all of the institutions reviewed, whereas the national mortality rate due to asthma has decreased from 3.5/100,000 inhabitants in 1987 to 2.9 in 1993, 2) the frequency of healthcare provided to asthmatics decreases between the ages of 15 to 24; 3) the disease occurs more frequently among males under 15 and in females over that age, 4) from August to November there was a significant rise in care provided for asthmatics in outpatient, emergency and hospital settings in Mexico City and almost every state studied; and 5) the frequency of care for asthmatics increases according to an increase in geographical altitude levels.

GSTM1 and GSTP1 and respiratory health in asthmatic children exposed to ozone.

Acute exposure to ozone has been related to a wide spectrum of health effects in susceptible individuals. Genetic factors may influence interindividual variation in ozone response. The current authors investigated the relationships between common polymorphisms in two genes involved in response to oxidative stress, i.e. glutathione S-transferases M1 (GSTM1) and P1 (GSTP1), and both respiratory symptoms and lung function in response to ozone among childhood asthmatics. A total of 151 asthmatic children, who were participants in a randomised controlled trial of antioxidant vitamin supplementation in Mexico City, were studied. Children were genotyped using PCR methods and followed from October 1998-April 2000. Increases in reported breathing difficulty were associated with ozone exposure in children with GSTM1 null (8%, 95% confidence interval (CI) 1-15%, per 20-ppb increase in 1-h maximum daily average over 7 days) or GSTP1 Valine/Valine (Val/Val) genotypes (14%, 95% CI 5-25%). In children with both GSTM1 null and GSTP1 Val/Val genotypes, the increase in breathing difficulty associated with a 20-ppb increase in ozone exposure was even greater (21%, 95% CI 5-39%). GSTP1 genotypes were not significantly associated with ozone-related lung function changes. In conclusion, asthmatic children with glutathione S-transferase M1 null and glutathione S-transferase P1 Valine/Valine genotypes appear more susceptible to developing respiratory symptoms related to ozone exposure.

[Allergic rhinosinusitis]. / Rinosinusitis alérgica.

Is a brief review of the allergic rhinosinusitis, the role of the immunology in the etiopathogenesis, remarking the importance of the good clinical study which is the corner stone of the diagnosis and which what others diseases make a differential diagnosis. We present also some of the ways to treat the rhinosinusitis including preventive drugs, hyposensitivity and symptomatic medications.

[Management of status asthmaticus in children]. / Manejo del "status asmaticus" en niños.

Acute bronchial asthmatic episodes represent one of the most common respiratory emergencies in medical practice. Its maximum expression "status asthmaticus", is an entity of low incidence in our medium, still it is a risk to the physical integrity of the patient. The management of an acute attack of asthma can be focused on doing away with the bronchial spasm and decreasing the inflammatory effects, as well as improve the movement of secretion and this way, maintain adequate alveolar ventilation. The full knowledge of the physiopathology behind the illness and medical treatment used to improve the patient's well-being, are necessary for the patient's full recuperation. The different components which comprise the integral management of an episode of status asthmaticus are analyzed in unison, emphasizing the data included in the clinical chart, medical management and other therapeutic measures employed.