PURPOSE: In extrinsic atopic dermatitis (AD), house dust mites (HDM) play a role in eliciting or aggravating allergic lesions. The nature of skin inflammation in AD has raised a growing interest in allergen-specific immunotherapy (SIT). Thus, we assessed clinical improvement and laboratory parameters for evaluation of the benefit of long-term SIT. MATERIALS AND METHODS: A total of 217 AD patients who were treated with SIT for at least 3 years were retrospectively assessed, by using their investigator global assessment, pruritus scores, loss of sleep (LOS), total serum IgE, and eosinophil counts collected. Patients were additionally classified into subgroups according to age, initial AD severity and mono- or multi-sensitization to include different individual factors in the evaluation of SIT efficacy. Lastly, we compared laboratory data of good responders to SIT with that of poor responders to SIT. RESULTS: Improvement after SIT therapy was observed in 192 out of 217 patients (88.4%). Among these patients, 138 (63.5%) achieved excellent, near-complete or complete clinical remission. Significant reduction of pruritus, LOS, and the mean value of total serum IgE were observed (p<0.01). Better outcome was found in patients younger than 12 years of age (p=0.024). Patients with moderate to severe AD showed better treatment outcomes (p=0.036). Patients sensitized only to HDM had the better response to treatment, but SIT was also effective in multi-sensitized groups (p=1.051). No significant differences in baseline laboratory results were observed between good and poor responders (p>0.05). CONCLUSION: We emphasize the usefulness of long-term HDM SIT as a disease-modifying therapy for AD.
Adolescent ; Adult ; Allergens/*immunology ; Animals ; Child ; Dermatitis, Atopic/*therapy ; Desensitization, Immunologic/*methods ; Dose-Response Relationship, Drug ; Female ; Humans ; Male ; Middle Aged ; Pyroglyphidae/*immunology ; Retrospective Studies ; Severity of Illness Index ; Treatment Outcome ; Young Adult

OBJECTIVETo investigate the risk factors for recurrent wheezing in infants and young children suffering from dust mite allergy after their first wheezing.

METHODSA total of 1 236 infants and young children who experienced a first wheezing episode and were hospitalized between August 2014 and February 2015 were enrolled, among whom 387 were allergic to dust mites. These infants and young children were followed up to 1 year after discharge. A total of 67 infants and young children who experienced 3 or more recurrent wheezing episodes within 1 year were enrolled as the recurrent wheezing group, while 84 infants and young children who did not experience recurrent wheezing during follow-up were enrolled as the control group. Univariate analysis and multivariate logistic stepwise regression analysis were performed to investigate the risk factors for recurrent wheezing in these patients.

RESULTSThe univariate analysis showed that the age on admission, wheezing time before admission, Mycoplasma pneumoniae infection rate, and influenza virus infection rate were associated with recurrent wheezing. The multivariate logistic stepwise regression analysis showed that the older age on admission (OR=2.21, P=0.04) and Mycoplasma pneumoniae infection (OR=3.54, P=0.001) were independent risk factors for recurrent wheezing.

CONCLUSIONSInfants and young children who are allergic to dust mites, especially young children, have a significantly increased risk of recurrent wheezing if they are complicated by Mycoplasma pneumoniae infection during the first wheezing episode.

Animals ; Child, Preschool ; Female ; Humans ; Hypersensitivity ; complications ; Infant ; Logistic Models ; Male ; Pyroglyphidae ; immunology ; Recurrence ; Respiratory Sounds ; etiology ; Risk Factors

OBJECTIVETo study the skin prick test (SPT) reactivity to house dust mite allergens in overweight and normal weight children with allergic asthma before and after standard subcutaneous specific immunotherapy.

METHODSTwo hundred and fifteen children with allergic asthma who had positive SPT responses to Dermatophagoides pteronyssinus (DP) and Dermatophagoides farinae (DF) were enrolled. According to the weight index, they were classified into overweight (n=63) and normal weight groups (n=152). Skin indices (SI) to DP and DF were compared between the two groups at 6 months and 1 year after standard subcutaneous specific immunotherapy.

RESULTSThe overweight group had a significantly larger histamine wheal diameter than the normal weight group after controlling the variation in testing time (P<0.05). After controlling the variation in weights, there were significant differences in the SIs to DP and DF before specific immunotherapy and at 6 months and 1 year after specific immunotherapy. At 6 months and 1 year after specific immunotherapy, the SIs to DP and DF were significantly reduced in both groups (P<0.05), and the overweight group had greater decreases in the SIs to DP and DF than the normal weight group.

CONCLUSIONSThe overweight children with allergic asthma have stronger responses to histamine than the normal weight patients. Specific immunotherapy can reduce the reactivity to dust mite allergens in children with allergic asthma. Within one year after specific immunotherapy, the overweight children with allergic asthma have a significantly greater decrease in the reactivity to dust mite allergens than the normal weight patients.

Adolescent ; Animals ; Asthma ; immunology ; therapy ; Child ; Child, Preschool ; Dermatophagoides farinae ; immunology ; Dermatophagoides pteronyssinus ; immunology ; Female ; Humans ; Immunotherapy ; Male ; Overweight ; immunology ; Pyroglyphidae ; immunology ; Skin Tests

What makes a certain molecule to elicit allergic responses? It has been a long-running question in allergology and immunology. Molecular properties of allergens have been characterized for last 30 years. However, it has become evident that allergen alone cannot induce allergic reactions. The way of introduction to the immune system and adjuvant-like activity of concomitantly administered molecules are thought to be important. Physical properties which facilitate delivery may characterize inhalant allergens. Buoyant and sticky antigens with small molecular weight (10-50 kDa) may be carried by particles and remain airborne. Most allergens could be grouped into allergen families according to biochemical properties. Protease, lipid-binding/transfer protein, actin-binding protein, Ca-binding protein, α-amylase/trypsin inhibitor, and pectate lyase account for a significant number of allergens. Biochemical properties which enhance the activation of Th2-immune responses could be another characteristic of allergens. The protease activity of allergens can help break the skin barrier or mucus membrane and its penetration into the body. The capacity of allergen to carry immunologically active substances could increase the allergenicity. Lipid-binding ability is believed to play a role in this aspect. Danger signals, such as endotoxin, β-glucan, and chitin derived from the pathogens, commensals and from the environment can enhance the immune response to allergens. The known characteristics of food allergens are resistance to heat, acid, and digestive enzymes. However, food processing makes it more complex. Understanding the intrinsic properties of allergens may shed light on the mechanisms on the pathogenesis of allergic disorders and improve the diagnostic and therapeutic approaches.
Allergens* ; Allergy and Immunology ; Chitin ; Food Handling ; Hot Temperature ; Humans ; Hypersensitivity ; Immune System ; Membranes ; Molecular Weight ; Mucus ; Particulate Matter ; Pollen ; Pyroglyphidae ; Skin

OBJECTIVE: We aimed to analyze the quality of life (QOL) in adults with allergic rhinitis according to the sensitization profile for relevant aeroallergens in Northern China, investigate the proportion of patients with coexisting asthma, and explore the correlation between QOL of rhinitis patients and the specific IgE level to the causative allergen. METHOD: One hundred and sixty-four allergic rhinitis patients participated in this study, whose clinical history, results of intradermal skin test and serum specific IgE levels to common aeroallergens in North China were collected. QOL was evaluated using the rhinoconjunctivitis quality of life questionnaire (RQLQ). RESULT: QOL of rhinitis patients was worse in those sensitized to tree pollens or weed pollens than those sensitized to house dust mites in Northern China. The proportion of patients with co-existing asthma was lower in tree pollen group than in house dust mite group or weed pollen group, and there was no significant difference between house dust mite group and weed pollen group. There was no significant correlation between QOL of rhinitis patients and the specific IgE level to the causative allergen. CONCLUSION In our study group, QOL of patients with allergic rhinitis varied with the allergen responsible for symptoms, but was not influenced by the specific IgE level to relevant allergen. The proportion of patients with co-existing asthma also varied with different pollen allergens. Rhinitis patients sensitized to weed pollens might be more likely to suffer from asthma than those sensitized to tree pollens.
Adult ; Allergens ; immunology ; Animals ; Asthma ; China ; Dermatophagoides pteronyssinus ; Humans ; Immunoglobulin E ; blood ; Pollen ; Pyroglyphidae ; Quality of Life ; Rhinitis, Allergic ; physiopathology

OBJECTIVETo retrospectively assess serious systemic adverse effects of standardized dust-mite vaccine in children with asthma.

METHODSMedical records of 704 children (5-17 years in age) with asthma between January, 2005 and December, 2011 were reviewed. Serious systemic adverse events following treatment with a standardized dust-mite vaccine in these children were analyzed.

RESULTSA total of 336 systemic adverse reactions were observed in 17.0% (120/704) of the patients analyzed of these adverse reactions, 18 (5.4%) were serious (level 3), 318 (94.6%) were not serious (below level 3), and no single case of anaphylactic shock (level 4) was recorded. Systemic adverse events occurred most frequently in the 5 to 11-year age group and in the summer season (from June to August). In the 18 severe cases, the peak expiratory flow (PEF) dropped by 20% immediately after the vaccine injection, and other major clinical symptoms included cough, wheezing and urticaria. All children with serious systemic adverse effects were given inhaled hormone and atomized short-acting beta agonists, oral antihistamines, intravenous dexamethasone and/or intramuscular adrenaline. After these treatments, the clinical symptoms were significantly relieved.

CONCLUSIONSThe rate of serious systemic adverse events following allergen-specific immunotherapy is relatively low in children with allergic asthma. Conventional medications are effective in managing these immunotherapy-associated adverse events.

Adolescent ; Animals ; Asthma ; physiopathology ; therapy ; Child ; Child, Preschool ; Desensitization, Immunologic ; adverse effects ; Female ; Humans ; Male ; Peak Expiratory Flow Rate ; Pyroglyphidae ; immunology ; Retrospective Studies ; Vaccines ; adverse effects

OBJECTIVEThe prevalence of allergic asthma has been rising continually which is correlated with the increasingly closed living environment. House dust mites are the major sources of indoor aeroallergens which induce asthma in sensitized people. To monitor the seasonal variation of house dust mite (HDM)-allergens exposure level in the asthmatic children, which was evaluated to show its correlation with the level of asthma control, HDM allergic sensitization and fraction of exhaled nitric oxide, and to provide basic data for HDM environmental control.

METHODA total of 48 HDM-allergic asthmatic children were enrolled from the asthma clinic in the hospital from March 2011 to January 2012 (boys 34 and girls 14, aging from 3 to 14 years, mean age 8 years and 4 months) in the present study. Dust samples from mattresses, pillows, bedroom floor, living room floor and sofas were collected in each season within one year in the household of all the enrolled patients. The concentrations of Der p 1 and Der f 1 were measured by the enzyme-linked immunosorbent assay (ELISA). To record the Asthma Control Test (ACT) score or Children Asthma Control Test (C-ACT) score for each patient and to collect the data of doctor monitoring asthma control level each time when the patient was clinic visited. The concentration and its classification of the serum specific IgE to HDM was determined by fluoroenzyme-immunometric assay.

RESULTThe average concentration of Der f 1 of all dust samples was significantly higher than that of Der p 1 (0.13 µg/g vs 0.02 µg/g, P < 0.05). The concentrations of Der f 1 from mattresses, pillows and sofas dust samples were significantly higher than those from bedroom floor and living room floor dust samples (0.69 µg/g, 0.42 µg/g and 0.22 µg/g vs 0.07 µg/g and 0.07 µg/g, P < 0.05). The Der f 1 exposure level from mattress dusts in summer but no others was negatively correlated with asthma control level (r = -0.318, P = 0.036). The Der f 1 exposure level from any area dusts in summer and the Der p 1 exposure level from pillows dusts in autumn was negatively correlated with ACT/C-ACT score respectively. The Der f 1 from mattress dusts in winter was positively correlated with classification of sIgE to Der f 1. The Der p 1 exposure level from most areas in each season was positively correlated with classification of sIgE to Der f 1 and Der P 1.

CONCLUSIONDer f 1 was the predominant mite allergen in household dust and mainly came from mattresses, pillows and sofas. The role of the HDM allergen exposure level on the asthma control level and HDM allergic sensitization for the asthmatic children were depended on its area, season and HDM species, which suggested that the future assessment of clinical effect by the HDM environmental control should consider these factors.

Adolescent ; Air Pollution, Indoor ; adverse effects ; Animals ; Antigens, Dermatophagoides ; analysis ; Asthma ; diagnosis ; etiology ; immunology ; Child ; Child, Preschool ; Dust ; Environmental Exposure ; Enzyme-Linked Immunosorbent Assay ; Female ; Forced Expiratory Volume ; Humans ; Immunoglobulin E ; blood ; Male ; Pyroglyphidae ; immunology ; Risk Factors ; Seasons

PURPOSE: House dust mites (HDMs) are an important source of indoor allergens associated with asthma, rhinitis and atopic dermatitis. Chicken immunoglobulin (Ig) Y is known to be a good alternative to mice and rabbit antibody production. In this study, we produced IgYs specific to HDMs and investigated their IgE immunoreactivities. MATERIALS AND METHODS: Total IgYs were isolated from the yolks of White Leghorn hens immunized with either Dermatophagoides pteronyssinus or D. farinae protein extract. Control antibodies were separated from the yolks of immunized hens with phosphate buffered saline. IgYs specific to HDMs were analyzed using enzyme-linked immunosorbent assay and Western blotting analysis. RESULTS: The concentration of egg IgY specific to D. farinae in an immunized hen increased and the highest achieved was 661.3 ug/mg (per an egg) on day 47, compared with 760 ug/mg IgY specific to D. pteronyssinus on day 16. The D. pteronyssinus or D. farinae-specific IgY was detected by binding of each mite proteins, and their immunoreactivities were elevated dependent of the specific IgY concentration. CONCLUSION: IgY specific to HDMs may be a promising antibody for immunological diagnosis as well as identification of possible resistance relating to HDM allergy.
Allergens/*immunology ; Animals ; Antibodies/*immunology ; Chickens ; Egg Yolk/*immunology ; Female ; Immunoglobulins/*immunology ; Pyroglyphidae/*immunology

OBJECTIVETo investigate impact factors for the efficacy of specific immunotherapy (SIT) in children with dust mite allergic asthma.

METHODSNinety-nine children with house dust mite allergic asthma received standardized SIT, and the level of asthma control was evaluated after 6 months (S1 stage), 12 months (S2 stage), 18 months (S3 stage), and 24 months (S4 stage) of treatment. The age of first visit, course of asthma, level of asthma severity, initial serum specific immunoglobulin E (sIgE) level, combination with allergic rhinitis or atopic dermatitis, use of inhaled corticosteroids, and local or systemic side effects during treatment were recorded, and their impacts on the level of asthma control were analyzed.

RESULTSAs the SIT proceeded, the number of clinically controlled cases increased significantly (P<0.01). The level of asthma control was significantly affected by the age of patients at first visit in S1 and S3 stages, and combination with allergic rhinitis or atopic dermatitis in S1 stage (P<0.05). In all stages of SIT, the controlled cases had significantly higher initial serum sIgE levels than the uncontrolled cases (P<0.05). In S1 and S2 stages, there was a significantly higher proportion of controlled cases among children with a high level of asthma severity than among those with a low level of asthma severity (P<0.05).

CONCLUSIONSThere is a positive correlation between long-term efficacy of SIT and the course or the total dose of treatment. Patients with higher initial serum sIgE levels achieve clinical control earlier than those with lower initial serum sIgE levels during SIT.

Adolescent ; Animals ; Asthma ; immunology ; therapy ; Child ; Child, Preschool ; Desensitization, Immunologic ; Female ; Humans ; Immunoglobulin E ; blood ; Male ; Pyroglyphidae ; immunology

OBJECTIVETo evaluate the therapeutic efficacy of 3-year subcutaneous immunotherapy (SCIT) in asthmatic children allergic to mite.

METHODSNinety asthmatic children allergic to house dust mite (with or without allergic rhinitis) and aged 5-14 years were randomized into SCIT treatment group (n=45) and control group (n=45). The SCIT treatment group received SCIT combined with standardized treatment for asthma, while the control group received the standardized treatment alone. The therapeutic effects were assessed based on the daytime and nighttime symptom scores, mean daily doses of inhaled corticosteroids (ICS), skin prick test results, peak expiratory flows and total serum IgE at baseline and in the 3-year treatment.

RESULTSIn both groups, the daytime and nighttime symptom scores in the first, second, and third years of treatment were significantly lower than the baseline values (P<0.01), and the scores decreased year by year during the 3-year treatment (P<0.01). Also, the mean daily doses of ICS in the first, second, and third years of treatment were significantly lower than the baseline values (P<0.01), and the doses decreased year by year during the 3-year treatment (P<0.01). The mean daily dose was significantly lower in the SCIT treatment group than in the control group in the second and third years of treatment (P<0.05). After 3-year treatment, the SCIT treatment group had a significantly higher proportion of children who discontinued use of ICS due to remission of symptoms compared with the control group (29% vs 20%, P<0.05). At the end of the 3-year treatment, the total serum IgE was significantly lower than the baseline value in the SCIT treatment group (P<0.01), and it was significantly lower in the SCIT treatment group than in the control group (P<0.05).

CONCLUSIONSThree-year SCIT is effective in asthmatic children allergic to house dust mite and allows reduction in the dosage of ICS.

Adrenal Cortex Hormones ; administration & dosage ; Animals ; Asthma ; immunology ; therapy ; Child ; Desensitization, Immunologic ; adverse effects ; methods ; Female ; Humans ; Immunoglobulin E ; blood ; Injections, Subcutaneous ; Male ; Pyroglyphidae ; immunology