Environmental Concerns for Children with Asthma on the Navajo Nation.

RATIONALE: Navajo children living on the reservation have high rates of asthma prevalence and severity. Environmental influences may contribute to asthma on the Navajo Nation and are inadequately understood. OBJECTIVES: We performed a comprehensive, integrative literature review to determine the environmental factors that may contribute to increased asthma prevalence and severity among Navajo children living on the reservation. METHODS: A systematic search was conducted in four databases regarding the environmental risk factors for asthma in Navajo children living on the reservation. Relevant studies between 1990 and 2017 were examined. Nonexperimental literature was also integrated into the review to describe the environmental injustices that have historically, disproportionately, and systematically affected the Navajo people, thus contributing to respiratory disparities among Navajo children. RESULTS: Eight studies met inclusion criteria for systematic review; however, limited research regarding environmental risk factors specific to asthma and Navajo children living on the reservation was identified. Our integrative review indicated both indoor and outdoor environmental risk factors commonly found on the Navajo reservation appear to be important determinants of asthma. CONCLUSIONS: Future research should examine indoor and outdoor air pollution from wood-burning stoves and cook stoves, coal combustion, tobacco and traditional ceremonial smoke, diesel exhaust exposure from long bus rides, indoor allergens, ambient pollutants, and regional dusts. Comprehensive mitigation efforts created in partnership with the Navajo Nation are necessary to address less-recognized risk factors as well as the common risk factors known to contribute to increased childhood asthma prevalence and severity.

Active treatment for food allergy.

Food allergy has grown in rapidly in prevalence, currently affecting 5% of adults and 8% of children. Management strategy is currently limited to 1) food avoidance and 2) carrying and using rescue intramuscular epinephrine/adrenaline and oral antihistamines in the case of accidental ingestion; there is no FDA approved treatment. Recently, oral, sublingual and epicutaneous immunotherapy have been developed as active treatment of food allergy, though none have completed phase 3 study. Efficacy and safety studies of immunotherapy have been variable, though there is clearly signal that immunotherapy will be a viable option to desensitize patients. The use of bacterial adjuvants, anti-IgE monoclonal antibodies, and Chinese herbal formulations either alone or in addition to immunotherapy may hold promise as future options for active treatment. Active prevention of food allergy through early introduction of potentially offending foods in high-risk infants will be an important means to slow the rising incidence of sensitization.

Pharmacologic options for the treatment and management of food allergy.

Food allergy affects approximately 5% of adults and 8% of children in developed countries, and there is currently no cure. Current pharmacologic management is limited to using intramuscular epinephrine or oral antihistamines in response to food allergen exposure. Recent trials have examined the efficacy and safety of subcutaneous, oral, sublingual, and epicutaneous immunotherapy, with varying levels of efficacy and safety demonstrated. Bacterial adjuvants, use of anti-IgE monoclonal antibodies, and Chinese herbal formulations represent exciting potential for development of future pharmacotherapeutic agents. Ultimately, immunotherapy may be a viable option for patients with food allergy, although efficacy and safety are likely to be less than ideal.

Bronchial hyperreactivity in non-atopic children with asthma and reflux: effect of anti-reflux treatment.

INTRODUCTION: The prevalence of bronchial hyperreactivity (BHR) or the effect of anti-reflux treatment on BHR in children with asthma and gastroesophageal reflux disease (GERD) is not known. METHODS: Thirty non-atopic children with persistent asthma were studied. Extended esophageal pH monitoring was used to diagnose GERD and methacholine challenge test (MCT) was used as a marker of BHR and performed before and 2 years after anti-GERD treatment. RESULTS: Of the 21 patients positive for GERD (group A), 15 had positive MCT suggesting BHR. Of the 9 patients negative for GERD (group B), 5 had positive MCT. On repeat testing 2 years later, 11/15 group A patients and 3/5 group B patients tested negative for BHR. Group A patients were receiving fewer asthma medications and experienced fewer exacerbations than Group B patients. CONCLUSIONS: BHR is prevalent in children with asthma and GERD and improves with anti-GERD treatment.

Associated factors in children with chronic cough.

BACKGROUND: Children presenting with chronic cough are common to the primary care physicians, but data on the etiology are scant. METHODS: We evaluated 40 children (age range, 5 to 12 years) with chronic cough (> 8 weeks duration) with no obvious cause who were referred by their primary care physicians. All patients underwent an extensive multispecialty workup that included pulmonary, GI, allergy, immunology, and otorhinolaryngology testing. Response to treatment was quantified pretreatment and 8 weeks after treatment by using a visual analog scale. RESULTS: Positive diagnostic test results were noted for gastroesophageal reflux disease (27.5%), allergy (22.5%), asthma (12.5%), infection (5%), aspiration (2.5%), and multiple etiologies (20%). Appropriate treatment for these factors resulted in a significant improvement in cough. CONCLUSION: Reflux, allergy, and asthma accounted for > 80% of the likely etiologic factors of chronic cough in children and responded to appropriate treatment.

Prevalence of IgE reactivities in mold-allergic subjects to commercially available fungal enzymes.

Fungi are important aeroallergens. However, fungal allergen sources of consistent quality for clinical testing are not readily available. Because some allergens have been identified as enzymes, we assessed the prevalence of IgE reactivity to commercially available fungal enzymes. The purpose of this study was to determine IgE antibody reactivity by radioallergosorbent assay (RAST) to commercially available fungal enzymes in mold-allergic individuals. Sera from 20 subjects with symptoms of respiratory allergies and skin test reactivity to 2 or more fungal allergens (4 conidial [imperfecti] fungi and/or 8 basidiomycetes) were selected. Controls were six atopic individuals with neither history of fungal allergy nor skin test reactivity to fungi. Seventeen commercial fungal enzymes were used as antigens to evaluate the subjects' IgE antibody reactivity by RAST. Sera from most fungus-allergic individuals showed substantial IgE antibody reactivity to enzymes; control sera showed little or no reactivity. The mean reactivity to all commercial enzymes of all subjects tested was RAST > or = 3% with only one exception. The most reactive fungal enzymes were invertase (bakers' yeast, Saccharomyces cerevisiae), cellulase (Trichoderma viride), and glucosidase (brewers yeast, S. cerevisiae) with mean binding of 14.6, 9.5, and 8.8%, respectively. Using RAST results with a combination of four enzymes from S. cerevisiae (brewers yeast glucosidase, bakers' yeast maltase, invertase, and invertase V), a sensitivity of 100% was shown for detecting mold-allergic patients. The studies suggest that fungal enzymes may be useful source materials for the identification of fungal allergens and may also provide readily available source materials to produce improved diagnostic and therapeutic reagents.