Burden of atopic dermatitis in Japanese adults: Analysis of data from the 2013 National Health and Wellness Survey.

Atopic dermatitis is a chronic inflammatory skin disease. The objective of this study was to characterize the burden of atopic dermatitis in Japanese adult patients relative to the general population. Japanese adults (≥18 years) with a self-reported diagnosis of atopic dermatitis and adult controls without atopic dermatitis/eczema/dermatitis were identified from the 2013 Japan National Health and Wellness Survey. Atopic dermatitis patients were propensity-score matched with non-atopic dermatitis controls (1:2 ratio) on demographic variables. Patient-reported outcome data on comorbidities, mood and sleep disorders, health-related quality of life, work productivity and activity impairment, and health-care resource utilization were analyzed in atopic dermatitis patients and matched controls. A total of 638 Japanese adult patients with atopic dermatitis were identified, of whom 290 (45.5%) rated their disease as "moderate/severe" and 348 (54.5%) as "mild". The analysis cohort comprised 634 atopic dermatitis patients and 1268 matched controls. Atopic dermatitis patients reported a significantly higher prevalence of arthritis, asthma, nasal allergies/hay fever, anxiety, depression and sleep disorders compared with controls (all P < 0.001). Atopic dermatitis patients also reported a significantly poorer health-related quality of life, higher overall work and activity impairment, and higher health-care resource utilization (all P < 0.001). Self-rated disease severity was not associated with disease burden, except for a significantly higher overall work and activity impairment. In conclusion, Japanese adult patients with atopic dermatitis reported a substantial disease burden relative to adults without atopic dermatitis, suggesting an unmet need for effective strategies targeting disease management.

Comorbidities of asthma in U.S. children.

BACKGROUND: Few epidemiologic population-based data are available to describe the wide range of health conditions that affect children with asthma. We conducted this study to identify common comorbidities of asthma during childhood and compare the prevalences of selected comorbidities among children with and without asthma. METHODS: We analyzed weighted data from the 2012 National Health Interview Survey child sample, a sample of 10,954 U.S. children aged 3-17 years. Information about each child's health, including history of asthma and other health conditions, was provided by an adult proxy respondent. We conducted binomial regression to compare the prevalences of 41 selected health conditions among children with and without current asthma. RESULTS: An estimated 10.4% of children aged 3-17 years (n = 1202) were identified as having current asthma. Nearly all conditions considered were more common among children with than without asthma. Compared to children without asthma, children with asthma had higher prevalences of hay fever or respiratory allergies (prevalence difference [PD]: 30.5%; 95% CI: 26.6, 34.4), eczema or skin allergies (PD: 14.1%; 95% CI: 10.7, 17.5), sinusitis (PD: 11.3%; 95% CI: 8.4, 14.1), food or digestive allergies (PD: 10.4%; 95% CI: 7.7, 13.1), and difficulty with emotions, concentration, behavior, or getting along (PD: 7.9%; 95% CI: 4.7, 11.1). CONCLUSIONS: These results highlight the burden of comorbidities among children with asthma. Improved understanding of the impact of comorbidities among children with asthma may help develop best practices for the assessment, treatment, and control of coexisting health conditions.

Longitudinal assessment of airway responsiveness from 1 month to 18 years in the PIAF birth cohort.

The Perth Infant Asthma Follow-up (PIAF) study involves a birth cohort of unselected subjects who have undergone longitudinal assessments of airway responsiveness at 1, 6 and 12 months and 6, 11 and 18 years of age. The aim of this study was to determine the relationship between increased airway responsiveness throughout childhood and asthma in early adult life.Airway responsiveness to histamine, assessed as a dose-response slope (DRS), and a respiratory questionnaire were completed at 1, 6 and 12 months and 6, 11 and 18 years of age.253 children were initially recruited and studied. Airway responsiveness was assessed in 203, 174, 147, 103, 176 and 137 children at the above-mentioned time points, respectively (39 participants being assessed on all test occasions). Asthma at 18 years was associated with increased airway responsiveness at 6, 12 and 18 years, but not during infancy (slope 0.24, 95% CI 0.06-0.42; p=0.01; slope 0.25, 95% CI 0.08-0.49; p=0.006; and slope 0.56, 95% CI 0.29-0.83; p<0.001, respectively).Increased airway responsiveness and its association with asthma at age 18 years is established between infancy and 6 years. We propose that airway responsiveness in early life reflects the initial airway geometry and airway responsiveness later in childhood increasingly reflects immunological responses to environmental influences.

A Multiple Indicators Multiple Cause (MIMIC) model of respiratory health and household factors in Chinese children: the seven Northeastern cities (SNEC) study.

In China, with the rapid economic development and improvement of living standards over the past few decades, the household living environment has shifted dramatically. The aim of the present study is to assess the impact of home environment factors on respiratory symptoms and asthma in Chinese children. Investigators analyzed data collected in the 25 districts from the seven Northeastern cities to examine health effects on respiratory symptoms and asthma in 31,049 children aged 2-14 years. Factor analysis was used to reduce 33 children's lifestyle and household variables to six new 'factor' variables. The multiple indicators multiple causes approach was used to examine the relationship between indoor air pollution and respiratory health status, controlling for covariates. Factor analyses generated six factor variables of potential household risk factors from an original list of 33 variables. The respiratory symptoms and asthma were significantly associated with the recent home renovation factor (estimate = 0.076, p < 0.001), pet ownership factor (estimate = 0.095, p < 0.001), environmental tobacco smoke (ETS) exposure factor (estimate = 0.181, p < 0.001) and PVC-flooring factor (estimate = 0.031, p = 0.007). Home ventilation factor was not related to any respiratory condition (estimate = 0.028, p = 0.074). Independent respiratory health effects existed for multiple household environmental factors recent home renovation, pet ownership, ETS, and PVC-flooring.

Environmental home inspection services in Western Europe.

This review deals with environmental home inspection services in Western Europe provided for patients at the request of attending physicians to improve patient management. Such requests are usually motivated by respiratory or general symptoms which occur or worsen at home. The visit includes a standardised questionnaire as well as environmental sampling such as mite-allergen measurement, mould identification and volatile organic compound (VOC) measurements. Besides, some non-respiratory indoor risks are also taken into account. Following the visit, a report is sent to the family and the attending physician. These services have been developed since the early 1990s, but evaluation of their efficacy is still limited. Some studies have demonstrated a reduction in mite-allergen levels and clinical improvement following the visit and implementation of advice provided to the family. However, more studies are needed to further document efficacy and also perform cost-benefit analysis of these services.

Health surveillance of workers exposed to laboratory animal allergens.

BACKGROUND: Laboratory animal allergy (LAA) remains prevalent among workers exposed to laboratory animals. Pre-placement and health surveillance procedures vary between different employers. AIMS: To determine evidence-based strategies for pre-placement and periodic health assessments for workers exposed to laboratory animals. METHODS: Literature was searched systematically using Medline and EMBASE for articles published in all languages up to the end of May 2010. Evidence-based statements and recommendations were graded according to a modified Royal College of General Practitioner's star system. RESULTS: Hundred and nine studies were identified from the literature search; 59 of these were accessed for critical appraisal and 50 contributed to the evidence statements. CONCLUSIONS: We recommend that laboratory animal workers should have a baseline health assessment that includes a health questionnaire, face-to-face assessment and spirometry. Identification of specific immunoglobulin E to common aero-allergens and to domestic and laboratory animal allergens may be used to identify workers who would benefit from further advice about managing their exposure, where risk assessment indicates that this might be prudent. Thereafter health surveillance should be performed by administering an appropriate health questionnaire, covering upper and lower respiratory, eye and skin symptoms on exposure, and wheals with animal scratches. The questionnaire should be administered at increased frequency for the first few years, the frequency being determined by a risk assessment. Where a worker develops new symptoms suggestive of LAA or where an asthmatic employee experiences deterioration either in symptoms or in control, they should be assessed further and a multicause multidisciplinary investigation performed.

Assessment of respiratory health surveillance for laboratory animal workers.

BACKGROUND: Occupational asthma is the most common work-related respiratory disease in the UK. Individuals whose work potentially puts them at risk include those exposed to laboratory animals. Workplace health surveillance programmes aim to minimize these health risks but are recognized to be challenging to implement effectively. AIMS: To evaluate the efficacy of the respiratory health surveillance programme provided by a National Health Service occupational health service (OHS) to individuals potentially exposed to respiratory sensitizers at work with laboratory animals. METHODS: Case notes from the OHS respiratory health surveillance programme over a 2 year period were examined. Symptom detection by the OHS surveillance questionnaire was compared to a cross-sectional survey using items from the validated International Union Against Tuberculosis and Lung Disease (IUATLD) questionnaire. The surveillance spirometry records were audited against good standards of practice. RESULTS: The response rate for the anonymized survey using IUATLD questions was 60% and detected similar numbers of potential work-related symptoms to the OHS surveillance questionnaire. Over 80% of spirometry records met accepted standards for technique, effort and recording. In this study of 85 individuals over 2 years, three cases of occupational asthma were identified. CONCLUSIONS: The current surveillance appears to be effective in identifying potential cases of occupational asthma. Modification of the questionnaire content and layout might improve response rates. This study suggests that spirometry does not detect new cases other than those already identified by questionnaire.

The use of frequency scale for the symptoms of GERD in assessment of gastro-oesophageal reflex symptoms in asthma.

In adult asthmatics the incidence of gastro-oesophageal reflux disease (GERD) reportedly ranges from 34% to 89%. Oesophageal pH monitoring and endoscopy are not required in the patient with typical GERD symptoms before the initiation of a therapeutic trial. Diagnosis of GERD on the basis of history is the simplest and quickest method, placing no demand on patients. Recently, a new questionnaire (FSSG; Frequency Scale for the Symptoms of GERD) was produced to evaluate the severity and the therapeutic response of GERD. The FSSG (F-scale) was used to assess the GERD in subjects with persistent moderate to severe asthma treated with anti-inflammatory asthma medication. In the present study, 27.4% of the patients with asthma had symptoms suggestive of GERD. There is significant correlation between GERD symptom (F-scale score) and severity of cough and sputum. The observations suggested that reflux symptoms, not gastric dysmotility symptoms, significantly associated with severity of cough, not of sputum. It is the first such study to use a FSSG as incidence of GERD symptoms in asthmatics and examine the relationship between F-scale score and asthmatic symptoms.

The social determinants of child health: variations across health outcomes - a population-based cross-sectional analysis.

BACKGROUND: Disparities in child health outcomes persist despite advances in medical technology and increased global wealth. The social determinants of health approach is useful in explaining the disparities in health. Our objective in this paper is four-fold: (1) to test whether the income relationship (and the related income gradient) is the same across different child health outcomes; (2) to test whether the association between income and child health outcomes persists after controlling for other traditional socioeconomic characteristics of children and their family (education and employment status); (3) to test the role of other potentially mediating variables, namely parental mental health, number of children, and family structure; and (4) to test the interaction between income and education. METHODS: This population-based cross-sectional study used data from the 2003 US National Survey of Children's Health involving 102,353 children aged 0 to 17 years. Using multivariate logistic regression models, the association between household income, education, employment status, parental mental health, number of children, family structure and the following child health outcomes were examined: presence or absence of asthma, headaches/migraine, ear infections, respiratory allergy, food/digestive allergy, or skin allergy. RESULTS: While the associations of some determinants were found to be consistent across different health outcomes, the association of other determinants such as household income depended on the specific outcome. Controlling for other factors, a gradient association persisted between household income and a child having asthma, migraine/severe headaches, or ear infections with children more likely to have the illness if their family is closer to the federal poverty level. Potentially mediating variables, namely parental mental health, number of children, and family structure had consistent associations across health outcomes. CONCLUSION: There appears to be evidence of an income gradient for certain child health outcomes, even after controlling for other traditional measures of socioeconomic status. Our study also found evidence of an association between certain child health outcomes and potential mediating factors.

[Prevalence of allergic diseases in Mexico City]. / Prevalencia de las enfermedades alérgicas en la Ciudad de México.

BACKGROUND: There is a considerable variation in the prevalence of allergic disorders in developing countries. These differences may be attributable to different methodological problems and to the lack of operational definitions. Several studies suggest that the prevalence of allergic diseases has been increasing worldwide in recent years. However, in Mexico, there is no data in open population. OBJECTIVE: To know in open population the prevalence of allergic diseases in the counties of Mexico City, the frequence of symptoms in each allergic disease, the therapeutic modalities that patients seek, the school and work annual absences and the amount of money that each patient spends in antiallergic drugs. PATIENTS AND METHODS: It was an open-population, cross-sectional trial, in two phases with a random sample size of 8,000 individuals from 214 public health centers. Statistical analysis was made with Excel 97-2004: Mann-Whitney U test for continuous variables and chi-square-test for discrete variables, p < 0.05 was considered statistically significant. RESULTS: The prevalence of allergic diseases in Mexico City was 42.6%, allergic rhinitis was the most frequent. Children are the largest age group affected. The highest prevalence was found in Tlahuac county. Coexistence of allergic diseases was found in 19.9%. The 44.2% of allergic patients attended to their general practitioner. 20.4% of all patients spent 10-20% of their income in medicines and 26% do not have money to buy antiallergic drugs. School and work annual absences are 3.37 +/- 3.86 and 6.2 +/- 12.84 days, respectively. CONCLUSION: Allergic diseases must be considered a public-health problem in Mexico City.

[Assessment of Polish physicians' therapy behaviour and patterns of prescribing antihistaminic medicines in day-to-day outpatient care]. / Ocena zachowan terapeutycznych lekarzy w Polsce w codziennej praktyce ambulatoryjnej odnosnie przepisywania leków przeciwhistaminowych.

AIM OF THE STUDY: The aim of the study was to assess management of patients with allergies, to evaluate frequency of use of specific antihistamines in population with diagnosed allergy, to evaluate causes and frequency of antihistamines' discontinuation, as well as frequency of allergen identification. MATERIAL AND METHOD: This was a multi-centre, observational study, in the form of epidemiological registry. The study was conducted in 1200 centres all over the country. 23 997 patients with diagnosed allergic condition were enrolled into this study. RESULTS: The most frequent allergic condition in the surveyed population was allergic rhinitis (51% of all enrolled patients), urticaria (28%), and allergic conjunctivitis (20%). Only 6 562 subjects (27%) had been examined with skin prick tests or specific IgE antibodies tests and their allergens had been identified. The remaining subjects had been treated so far with no attempts to identify allergy triggers (allergens). In the surveyed population, the dominant type was pollen allergy (62%) and house dust mites allergy (33%). Only 48% of subjects were on antiallergic treatment at the time of the enrollement into this epidemiological registry. The main causes of medication discontinuation were side effects observed, predominantly sedation. CONCLUSIONS: The most frequent allergic condition treated in outpatient setting is allergic rhinitis. Only 48% of allergic patients take antiallergic medicines (predominantly antihistamines). The most prevalent reason for treatment discontinuation are side effects, mainly sedation.

[Prevalence of allergic diseases in the elderly]. / Prevalencia de enfermedades alérgicas en adultos mayores.

BACKGROUND: A population aged 65 and over has been increasing in many countries, including Mexico. Allergic diseases are common in this age group, asthma prevalence has been reported between 2 and 17% in elderly people. There is no data about allergic diseases prevalence in elderly Mexican people. OBJECTIVE: To know the prevalence of some allergic diseases, allergen sensitization and total IgE serum concentration in a sample of subjects older than 60 years residents in Mexico City. PATIENTS AND METHODS: We included 333 elderly subjects, were included 281 females (84%) and 52 males, with an age-average of 67.2 +/- 5.4, who were attending a social security recreative center. Medical files were made to each one elderly subject, including atopic personal history; skin tests were performed with 10 allergens, histamine and negative controls; and total serum IgE was measured by ELISA. Analysis was made with descriptive statistics, Spearman's coefficient and chi square. RESULTS: Allergic diseases were present in 10.8% of the subjects, asthma in 3.6%, allergic rhinitis in 3.6%, urticaria in 2.7%, atopic dermatitis in 0.6% and allergic conjunctivitis in 0.3%, 24% had data of adverse drug reactions and 6.9% referred venom insect hypersensitivity. Skin tests results were positive in 84 subjects (25.2%). In the group of 60-69 years it was observed a significant increase in IgE concentration (p < 0.01), we didn't find a significant correlation between IgE levels and both allergic symptoms and skin tests results. CONCLUSIONS: The prevalence of allergic diseases, total IgE levels and allergen sensitization in elderly people were similar to studies in other countries, but with a lower pattern than in younger Mexican population.

Airway inflammation contributes to health status in COPD: a cross-sectional study.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is characterized by irreversible airflow limitation and airway inflammation, accompanied by decreased health status. It is still unknown which factors are responsible for the impaired health status in COPD. We postulated that airway inflammation negatively contributes to health status in COPD. METHODS: In 114 COPD patients (99 male, age: 62 +/- 8 yr, 41 [31-55] pack-years, no inhaled or oral corticosteroids, postbronchodilator FEV1: 63 +/- 9% pred, FEV1/IVC: 48 +/- 9%) we obtained induced sputum and measured health status (St. George's respiratory questionnaire (SGRQ)), postbronchodilator FEV1, hyperinflation (RV/TLC), and airway hyperresponsiveness to methacholine (PC20). Sputum was induced by hypertonic saline and differential cell counts were obtained in 102 patients. RESULTS: Univariate analysis showed that SGRQ total and symptom score were positively associated with % sputum macrophages (r = 0.20, p = 0.05; and r = 0.20, p = 0.04, respectively). Multiple regression analysis confirmed these relationships, providing significant contributions of % sputum macrophages (B = 0.25, p = 0.021) and RV/TLC (B = 0.60, p = 0.002) to SGRQ total score. Furthermore, SGRQ symptom score was associated with % sputum macrophages (B = 0.30, p = 0.03) and RV/TLC (B = 0.48, p = 0.044), whilst SGRQ activity score was associated with % sputum macrophages (B = 0.46, p = 0.002), RV/TLC (B = 0.61, p = 0.015), and PC20 (B = -9.3, p = 0.024). Current smoking and FEV1 were not significantly associated with health status in the multiple regression analysis. CONCLUSION: We conclude that worse health status in COPD patients is associated with higher inflammatory cell counts in induced sputum. Our findings suggest that airway inflammation and hyperinflation independently contribute to impaired health status in COPD. This may provide a rationale for anti-inflammatory therapy in this disease.

Risk assessment in elderly for sensitization to food and respiratory allergens.

For elderly people, epidemiological data are rare for respiratory allergies and completely missing for food allergies. The aim of this study was to examine the prevalence and risk factors for sensitizations in 109 people with a mean age of 77 years, who are living in a geriatric nursing home. The cross-sectional study included a detailed interview, skin prick tests, and serum tests for specific and total IgE, IFN-gamma, and ST2, a marker for Th2-lymphocyte activity. Almost all study subjects (n=101) suffered from co-morbidity, 14 from type I allergy, 25 from gastrointestinal disorders treated with anti-ulcer drugs, 25 were chronic alcoholics and 21 were smokers. The total IgE levels were significantly higher in men (P=0.025), and not affected by smoking or alcohol consumption. Skin prick tests were positive in 41.7% of tested patients. Specific IgE to respiratory allergens was found in 40.4% of all patients and was elevated in men (P=0.013), with a significant correlation to smoking (P=0.029). Specific IgE to food allergens was detected in 24.8%, apparently without connection to the investigated risk factors. However, positive skin prick tests with food allergens could be correlated with chronic alcohol consumption (P=0.036). The intake of anti-ulcer medication was significantly correlated with elevated ST2 levels as an indirect readout for Th2-cell activity (P<0.001). The risk factors for sensitization in elderly to respiratory allergens were chronic damage of respiratory epithelia due to smoking, and for sensitization to food allergens chronic alcohol consumption.

Economic impact of workplace productivity losses due to allergic rhinitis compared with select medical conditions in the United States from an employer perspective.

OBJECTIVE: To evaluate the cost of lost productivity in the workplace due to allergic rhinitis compared to other selected medical conditions from an employer perspective. SETTING AND PARTICIPANTS: A total of 8267 US employees at 47 employer locations who volunteered to participate in health/wellness screenings. MEASUREMENTS: The Work Productivity Short Inventory was used to assess the impact of a predefined group of health conditions on workplace productivity for the previous 12 months. Both absenteeism and presenteeism (lost productivity while at work) were recorded. Costs were calculated using a standard hourly wage. RESULTS: Allergic rhinitis was the most prevalent of the selected conditions; 55% of employees reported experiencing allergic rhinitis symptoms for an average of 52.5 days, were absent 3.6 days per year due to the condition, and were unproductive 2.3 h per workday when experiencing symptoms. The mean total productivity (absenteeism + presenteeism) losses per employee per year were 593 US dollars for allergic rhinitis, 518 US dollars for high stress, 277 US dollars for migraine, 273 US dollars for depression, 269 US dollars for arthritis/rheumatism, 248 US dollars for anxiety disorder, 181 US dollars for respiratory infections, 105 US dollars for hypertension or high blood pressure, 95 US dollars for diabetes, 85 US dollars for asthma, and 40 US dollars for coronary heart disease. The mean total productivity loss per employee per year due to caregiving was 102 US dollars for pediatric respiratory infections, 85 US dollars for pediatric allergies, 49 US dollars for Alzheimer's disease, and 42 US dollars for otitis media/earache. CONCLUSIONS: Allergies are major contributors to the total cost of health-related absenteeism and presenteeism. Payers and employers need to consider this when determining health benefits for employees.

Burden of rhinitis in children with asthma.

Although the clinical association of allergic rhinitis and asthma has been recognized for centuries, in recent years the association appears to be stronger than was reported previously. However, data for children are less clear, and some studies indicate that results observed in developing countries may differ from those observed in Western populations. We therefore intended to document the association of rhinitis with pediatric asthma in terms of caregivers' perception, physician practice, and file records. Asthmatic children aged 3-16 years with at least 1-year follow-up in an allergy-asthma outpatient clinic were invited to participate in the study during a 10-month interval. In addition to a face-to-face questionnaire-based interview, file records were evaluated retrospectively to obtain information relating to asthma and rhinitis. Of 396 patients included in the study, 369 with consistent replies were included in the analyses. The mean age of the study group was 10.6 +/- 0.2 (mean +/- SEM) years, and a greater proportion of the respondents were male (63.7%), atopic (78.3%), and mildly asthmatic (50.7%). House dust mite and grass pollens were the most commonly sensitized allergens (50.7% and 46.9%, respectively). Although only 5.4% of our study population regarded themselves as rhinitic and 23.8% had been diagnosed with allergic rhinitis according to the file records, almost 57.7% of patients had required medications for rhinitis within the last year, and 68.8% had findings consistent with allergic rhinitis. Furthermore, 41.2% and 58.8% reported that their rhinitis symptoms caused a significant burden in their daily life and exacerbated their asthma, respectively, and almost 50% felt that their rhinitis had not been given significant consideration by their physician. In conclusion, although we report a large discrepancy between caregivers' perception of rhinitis, documentation in file records, and treatments for rhinitis, the allergic rhinitis prevalence determined in the survey and the medication use for rhinitis appeared to be in agreement. We recommend a greater effort be made to identify, label, and educate children with rhinitis and their families in asthma outpatient clinics.

Considering risks to healthcare workers from glutaraldehyde alternatives in high-level disinfection.

Due to concerns over glutaraldehyde's toxicity, two substitutes have recently been introduced; ortho-phthalaldehyde (OPA), and a mixture of hydrogen peroxide and peracetic acid. There is limited information about the health effects for employees from these products. This study assesses the current practices regarding the use of high-level disinfectants in British Columbian hospitals and predicts the relative toxicities of each product. Industry practices were compiled using a comprehensive survey of current practices and decision processes in all hospitals in British Columbia. Of 95 hospitals, 64 returned surveys; 80% of these used high-level disinfection. Among user hospitals, 49% used glutaraldehyde alone and 51% had introduced alternatives. Concern about staff health was the most common reason for substituting, but this was frequently not considered when choosing specific alternatives. Hospitals that involved occupational health, infection control or regional staff in high-level disinfectant decisions used glutaraldehyde alternatives less often. In most hospitals, it was difficult to find individuals who were knowledgeable about the use of disinfectants. Potential health effects associated with each type of high-level disinfectant were assessed by review of the published literature and available manufacturers' data along with qualitative structure-activity relationship analysis. Results indicated that although all products irritate the skin and respiratory tract, OPA is a potential dermal and respiratory sensitizer but hydrogen peroxide and peracetic acid do not cause allergic reactions. Despite little being known about the risks to employees from glutaraldehyde alternatives, their use is widespread. The potential risks of all high-level disinfectants are serious; thus regulators and users are faced with important risk management decisions before and after they have been introduced into the workplace.

Measurement of nasal IgE in an epidemiological study: assessment of its diagnostic value in respiratory allergy.

BACKGROUND: Specific questionnaire and skin prick test (SPT) are the most used methods in epidemiological studies on respiratory allergy. SPT, however, can be positive in many subjects without evidence of any allergic disease. Nasal IgE determination has been suggested by some authors as a valuable diagnostic method, which may overcome this lack of specificity. OBJECTIVE: The aim of this study was to evaluate sensitivity and specificity of nasal specific IgE for the seven most common inhalant allergens in order to verify its reliability as a screening test. METHODS: 126 children, involved in an epidemiological study on prevalence of respiratory allergic disease, were evaluated. All children were assessed with a specific questionnaire, SPT and nasal specific IgE. Nasal specific IgE were determined with a previously described method modified for screening purposes, in order to test seven allergens at the same time. When discordant results were obtained between questionnaire, SPT and nasal IgE, an allergen specific nasal challenge (ASNC) was performed and nasal tryptase was also determined before and after challenge. RESULTS: The questionnaire was positive for respiratory allergy in 28/126 children. SPT was positive in 21 of the 28 children, but also in 5/10 children with atopic dermatitis (AD), and in 12/88 children without allergic symptoms. Nasal IgE were positive in 22/28 and also in 2/10 with AD. Nasal challenge and tryptase confirmed the negativity of nasal IgE in 12/17 children with positive SPT but totally negative for allergic respiratory disease. Moreover nasal IgE was found to be positive to dermatophagoides in one of seven children with negative SPT despite a clinical history suggestive for mite respiratory allergy. In this patient and in 2 of the 5 children with AD the positive nasal IgE to mites was confirmed by a positive ASNC and tryptase. CONCLUSIONS: Nasal IgE have shown a specificity significantly higher than SPT (98% vs. 83%) and a good sensibility. This screening test may also be useful to detect the beginning of upper airways sensitization in patients with AD.