Indoor exposure assessment for levels of dust mite and total volatile organic compounds (TVOCs) in living houses.

The purpose of this study is to measure the levels of dust mites (Dermatophagoides farina group 1 [Der f1] and Dermatophagoides pteronyssinus group 1 [Der p1]) and total volatile organic compounds (TVOCs) in the resident environments with living conditions such as the number of ventilation; the number of window, floor, and temperature; and relative humidity (RH) from vulnerable class in South Korea. Information on residents is designed to be prepared by residents on their general characteristics (daily residence time, heating and cooking type, and cleaning on the day of sampling). Dust mites levels ranged from 24.0 to 1087.5 ng/g with a mean of 215.4 ng/g for Der f1 and from 0.6 to 489.9 ng/g with a mean of 489.9 ng/g for Der p1. Total TVOC levels ranged from 15.3 to 1642.1 µg/m3 with a mean of 219.7 µg/m3. The correlation analysis showed a positive association between Der f1 levels and xylene levels in fall (r = 0.49, r < 0.05) of this study.

House dust mite allergens and nitrated products: Identification and risk assessment in indoor dust.

Air pollutants can potentially lead to nitration of allergic proteins, thus promoting sensitization of these allergens. However, little is currently known about the nitration status of house dust mite (HDM) allergens. We identified the occurrence of nitrated products of two major HDM allergens Der f 1 and Der p 1 in dust samples collected from college dormitories in eastern China and assessed their associated health risk. The results showed that both non-nitrated and nitrated forms of the two allergens were detected in the dust in the range of non-detected (ND)-10.6, 1.44-15.4, ND-22.4, ND-7.28 µg/g for non-nitrated Der f 1, nitrated Der f 1, non-nitrated Der p 1 and nitrated Der p 1, respectively. The median rates of nitration were determined as 74.0% for Der f 1 and 20.4% for Der p 1 at consideration of one nitration site. Further analysis reveals that the levels of HDM allergens and their nitrated products were found to be generally higher during winter, in dormitories of lower altitude and with female occupants. Furthermore, the calculated risk indexes were at considerably high levels. Our findings suggest that nitrated HDM allergens have already accumulated in the environment at such significant levels and their associated health risk calls for our immediate attention.

Validated allergen exposure chamber is plausible tool for the assessment of house dust mite-triggered allergic rhinitis.

BACKGROUND: Allergen exposure chamber (AEC) is a clinical facility that allows exposure to allergenic airborne particles in controlled environment. Although AECs offer stable levels of airborne allergens, the validation of symptoms and other endpoints induced by allergen challenge is key for their recommendation as a plausible tool for the assessment of patients, especially in clinical research. This study aimed to demonstrate the reproducibility of defined clinical endpoints after AEC house dust mite (HDM) challenge under optimal conditions in patients with allergic rhinitis (AR). METHOD: HDM was distributed at different concentrations. The assessment was subjective by the patients: total nasal symptom score (TNSS), visual analog scale (VAS), and objective by the investigator: acoustic rhinometry, peak nasal inspiratory flow (PNIF), and nasal secretion weight. Safety was assessed clinically and by peak expiratory flow rate (PEFR) and forced expiratory volume in the first second (FEV1 ). RESULTS: Constant environment: temperature, humidity, and carbon dioxide (CO2 ) concentration were maintained during all challenges. The concentration of HDM on average remained stable within the targeted values: 1000, 3000, 5000, 7000 particles (p)/m3 . Most symptoms were observed at concentrations 3000 p/m3 or higher. The symptoms severity and other endpoints results were reproducible. 5000 p/m3 , and challenge duration of 120 min were found optimal. The procedure was safe with no lung function abnormalities due to challenge. CONCLUSION: HDM challenge in ALL-MED AEC offers a safe and reliable method for inducing symptoms in AR patients for the use in controlled clinical studies including allergen immunotherapy.

Detection and assessment of dust mite allergens in an indoor environment in Anhui, China.

Dust in the home environment is thought to be a potential trigger for increasing allergic diseases, such as allergic rash, rhinitis, asthma, and other conditions, associated with dust mites. To verify the status of dust mite prevalence in indoor surroundings, we collected 189 dust samples from the air conditioner filters (n = 75) and floors (n = 114) of households, schools, and hotels in the Anhui area, China. All samples were measured for dust mite breeding rate and breeding density under light microscopy and analyzed for dust mite species Dermatophagoides farinae 1 (Der f 1) and Dermatophagoides pteronyssinus 1 (Der p 1) allergen using enzyme-linked immunosorbent assay (ELISA). The dust mite breeding rates were 34.67% (26/75) and 20.18% (23/114), respectively, in the dust samples from the floor and air conditioning filters. The breeding density was the highest in households (10/g), followed by schools (9/g) and hotels (4/g). ELISA indicated that the allergen threshold (2.0 µg/g dust) of Der f 1 was exceeded in only two samples and Der p 1 in one sample. Additionally, a questionnaire was used to investigate the health knowledge on allergic diseases involved in indoor facilities, finding that most allergy sufferers were aware that indoor dust might be responsible for their conditions. The findings suggest that regular maintenance of indoor hygiene and cleaning of air-conditioning filters should reduce the risks of exposure to indoor allergens.

Simultaneous assessment of organophosphate flame retardants, plasticizers, trace metals, and house dust mite allergens in settled house dust.

Settled house dust (SHD) is a reservoir for various contaminants, including endocrine-disrupting chemicals (EDCs), trace metals, and house dust mite allergens. This study aimed to characterize various chemical and biological contaminants in SHD and identify determinants governing the indoor contaminants. In total, 106 SHD samples were collected from 106 houses in Seoul and Gyeonggi Province, Korea, in 2021. Bedding dust samples were collected from 30 of these 106 houses. All participants completed a questionnaire comprised of housing and lifestyle-related factors. The samples were analyzed for 18 organophosphate flame retardants (OPFRs), 16 phthalates, five alternative plasticizers (APs), seven trace metals, and two house dust mite allergens (Dermatophagoides farinae type 1 [Der f1] and Dermatophagoides pteronyssinus type 1 [Der p1]). A multiple regression analysis was conducted to identify the determinants governing the concentrations and profiles of various contaminants. OPFRs, phthalates, APs, and trace metals were detected in all SHD samples, indicating ubiquitous contamination in indoor environments. Among the three EDC groups, APs were detected at the highest concentrations (geometric mean [GM] (geometric standard deviation, [GSD]): 1452 (1.6) µg/g in total), followed by phthalates (GM (GSD): 676 (1.4) µg/g in total) and OPFRs (GM (GSD): 10 (1.4) µg/g in total). Der f1 was detected in all bedding dust samples with significantly higher levels than Der p1 (GM (GSD): 0.1 (1.8) µg/g vs. 1.4 × 10-3 (2.3) µg/g). The concentrations of OPFRs, plasticizers, and trace metals in SHD were significantly associated with the type and number of electronic appliances and combustion activities. Der f1 was significantly associated with the number of occupants and water penetration. Ventilation, vacuum cleaning, and wet cleaning or dry mopping significantly reduced the levels of most contaminants in SHD. As residents are persistently exposed to a wide array of pollutants, comprehensive and adequate measures are required to prevent potential exposures.

Cost-effectiveness analysis of house dust mite allergen immunotherapy in children with allergic asthma.

BACKGROUND: Cost-effectiveness studies evaluating allergen immunotherapy (AIT) in children are limited but needed to drive clinical and policy-making decisions such as reimbursement of new interventions. In this study, we compared the cost effectiveness of subcutaneous (SCIT) and sublingual immunotherapy (SLIT) tablets to the standard of care (SOC) treatment in children with house dust mite-driven (HDM) allergic asthma. METHODS: We developed a hypothetical Markov model based on the Global Initiative for Asthma (GINA) severity steps to compare the three strategies over a 10-year horizon divided by cycles of 6 months. SOC was used as a reference to calculate the incremental cost-effectiveness ratio (ICER). Deterministic and probabilistic sensitivity analyses were used to assess models' uncertainty. Other scenarios were evaluated to strengthen the presentation of results. RESULTS: The ICER for SCIT and SLIT tablets was 1281€ and 7717€, respectively. The cost-effectiveness threshold for Portugal was 18,482.80€; both treatment approaches were below this limit. The major contributors to these results were the AIT effects on reducing moderate and severe exacerbations and asthma controller medication. In the sensitivity analysis, SCIT revealed a higher probability of cost-effectiveness than SLIT. When including allergic rhinitis as comorbidity, ICER values reduced markedly, especially for SCIT intervention. CONCLUSIONS: AIT was cost effective in children with HDM-driven allergic asthma, especially when given by the subcutaneous route. The high probability of cost effectiveness, especially for SCIT, may drive future policy decisions and AIT-prescribing habits. AIT adherence greatly influenced the results highlighting the value of implementing strategies to promote adherence rates.

Evaluation and predictive value of IgE responses toward a comprehensive panel of house dust mite allergens using a new multiplex assay: a real-life experience on an Italian population.

Summary: Background. House dust mites (HDM) are among the most important allergen sources worldwide, representing a major cause of perennial allergic rhinitis and asthma. Aim. To evaluate the prevalence of IgE responses towards a comprehensive panel of HDM allergens and to evaluate the implications of molecular sensitization profiles on respiratory symptoms. Methods. 155 consecutive HDM-allergic patients (mean age: 27.5 years; range: 1-62; female: 63), 86 affected by rhinitis and 68 by asthma, were enrolled. Specific IgE reactivity to Der f 1, Der p 1, Der f 2, Der p 2, Der p 5, Der p 7, Der p 10, Der p 11, Der p 20, Der p 21 and Der p 23 was tested in patients' sera using the last version of the multiparametric assay Allergy Explorer (ALEX). Results. In all, major and minor allergens were positive, respectively, in 96.8% and 50.9% of the patients. Prevalence and IgE levels of Der f 1, Der f 2, Der p 1 and Der p 20 were significantly higher in asthmatic patients (p less than 0.05), whereas subjects negative for minor allergens resulted more frequently suffering from rhinitis (p = 0.0001). Asthmatic patients had IgE reactivity to a larger number of HDM allergens (mean 5.4; SD ± 2.3) than patients with only rhinitis (mean 4.2; SD ± 2.5) (p = 0.003), whereas no differences in the number of HDM positive molecules and in the specific IgE levels were found among different ages. Conclusions. This study confirms that the assessment of IgE to a comprehensive panel of HDM allergens defines different serological reactivity profiles that seem associated with different clinical presentations.

Satisfaction of allergic patients treated with house dust mite sublingual immunotherapy.

Sublingual immunotherapy (SLIT) has been used for more than three decades as a therapeutic strategy for the treatment of allergic diseases. Studies have demonstrated its efficacy and safety, and numerous clinical trials have evaluated these parameters. In the present study, through patient perception, we investigated the patient satisfaction with the use of house dust mite SLIT treatment. "Satisfaction Scale for Patients Receiving Allergen Immunotherapy" (ESPIA) questionnaire, a standardized and validated instrument for clinical studies evaluating allergen immunotherapy, was applied to allergic patients (N = 136). Children and adults of both sexes who received SLIT for Dermatophagoides pteronyssinus and/or Blomia tropicalis, according to the results of an immediate reading puncture test, were included. Data analysis showed that the perception of treatment effectiveness was 92%, performance improvement in the daily activities was 91%, a satisfactory cost-benefit balance was 84%, and the perception of general satisfaction was 97%. The results showed a high perception of satisfaction in allergic patients undergoing house dust mite SLIT.

Aqueous intradermal low-dose house dust mite immunotherapy in tropical settings: a valid cost-effective approach for developing nations?

INTRODUCTION: Aqueous allergen injections, an effective and century-old technique, is considered a second-line approach in daily clinical practice. Inconveniences still surround conventional subcutaneous immunotherapy (SCIT) administration, such as a need for frequent injections, prolonged up-dosing schedules, elevated costs, and the unlikely possibility of a systemic reaction. The intradermal immunotherapy route (IDR) might favorably impact many of the aforementioned issues (Table 1). House dust mite (HDM) allergens are the main perennial sensitizers in the tropics, and as such, are solely employed in immunotherapy treatments. METHODS: We carried out a year-long real-life study in 25 perennial allergic rhinitis children, symptomatic on exposure to house dust, employing an intradermal low-dose allergen mix consisting of 50 ng of Dermatophagoides pteronyssinus/Dermatophagoides farinae and 120 ng of Blomia tropicalis, under a unique cost-wise protocol. Basal symptoms/signs and face Visual Analog Scale (fVAS) scores were recorded for 2 weeks and later compared with those registered throughout the 1-year treatment. Serum-specific IgG4 and IL-10 levels were employed in the assessment of the immune responses. RESULTS: Symptoms/signs and fVAS scores were significantly reduced from days 42 and 49, respectively, and remained so until treatment completion. Increases in specific IgG4's and IL-10 levels reflected significant immune responses. Injections were well tolerated and families reported improved health status (quality of life, QoL). CONCLUSIONS: A unique cost-effective immunotherapy alternative for deprived allergic communities in tropical settings is depicted; further research is needed.

[Allergy assessment: when and how?] / Allergieabklärung: wann und wie?

Allergy assessment: when and how? Abstract. Allergies are common in the clinical practice. The most important allergens are pollen, house dust mites, animal dander, mold and allergens attributable to a particular work environment. The medical history is a very important part for diagnosing an allergy, because sensitizations detected by skin prick tests and laboratory tests are common but not always symptomatic and therefore without clinical relevance. There are 3 options to manage allergic diseases: avoidance of allergens, symptomatic treatment and - in selected cases - a causal treatment like allergen-specific immunotherapy.

[An assessment of the sublingual immunotherapy with Dermatophagoides farinae on asthma control level and pulmonary function of allergic asthma and rhinitis in adult patient].

Objective:To evaluate the efficacy, asthma control level and pulmonary function of sublingual immunotherapy on allergic asthma and rhinitis in adult patient. Method:This retrospective analysis of 182 cases of adult patient from 18-60 years with allergic asthma and rhinitis, according to the patients' wishes they were divided into drug group（66 patients） and SLIT group（116 patients）. Drug group patients were treated with low to moderate doses of inhaled corticosteroids+long-acting ß2 receptor agonists and mometasone furoate nasal spray+desloratadine tablets as symptomatic treatment. SLIT group was treated by SLIT with Dermatophagoides farina drops on this basis. Before treatment and 1 year, 2 year and 3 years after treatment, the ACT, PEF%, DASS, NASS, TNSS and TMS were evaluated. Result:The ACT, PEF%, DASS, NASS, TNSS and TMS had continuously improved significantly 1 year, 2 year and 3 years after treatment in both groups comparing with baseline（P<0.05）. Compared with 1 year after treatment, SLIT group had lower ACT, PEF%, DASS, NASS, TNSS and TMS in 2 years after treatment（all P<0.05）, whereas drug group had lower TMS and DASS（all P<0.05）. In 3 years of treatment, only SLIT group resulted in significant continuous improvement in DASS and TMS（all P<0.05）. After 1 year, 2 and 3 years of treatment, SLIT group resulted in significantly better ACT, PEF%, DASS, NASS and TMS than drug group（all P<0.05）. After 2 and 3 years of treatment, TNSS of SLIT group were significantly lower than in drug group（P<0.05）. Conclusion:Sublingual immunotherapy for 3 yearswith Dermatophagoides farinae dropsin adult patient with allergic asthma and rhinitis was more effective than drug therapy alone, and asthma control and lung function improved significantly.

Socio-environmental profile of child and adolescents sensitized by house dust mite in northeast of Brazil.

INTRODUCTION: The association regarding the atopic sensitization to mite aeroallergens and the socio-environmental features is still inconsistent. OBJECTIVES: We analyzed the role played by socioeconomic and environmental factors in the prevalence of sensitization to house dust mite (HDM) allergens, and associated with the risk of developing asthma symptoms. PATIENTS AND METHODS: This is a case-control study conducted with 108 patients, aged 1-17. We inquired about family habits, socioeconomic and environmental features. We applied the International Study of Asthma and Allergies in Childhood questionnaire. RESULTS: We observed patients sensitized to all HDM tested, Derp (42%), Derf (37%) and Blot (33%). Middle family income (OR: 2.74; CI95%: 1.127-6.684), exposure to dog (OR: 3.758, CI95%: 1.127-6.684) and artificial climatization (OR: 4.319, CI95%: 1.398-13.348) were associated with sensitization to Derp. We also observed protective factors, such as sharing of dormitories, washing cycle for bedspreads and the presence of basic sanitation. An increased risk of sensitization to Derf was associated with Blot sensitization (OR: 3.172, CI95%: 1.083-9.292) and presence of mold on the walls (OR: 3.095, CI95%: 1.063-9.008). A protective factor was dormitory sharing. For sensitization to Blot, we observed an increase in the risk associated with Derp sensitization (OR: 3.462, CI95%: 1.191-10.061) and exposure to dog (OR: 3.255, CI95%: 0.987-10.736). In addition, sensitization to Blot increases the risk of developing asthma symptoms (OR: 2.732, CI95%: 0.981-7.606). CONCLUSION: Our data show distinct sociodemographic and environmental relations that lead to HDM sensitization and increased probability of development of allergic diseases.

Clinical Characteristics and Allergen Sensitization Patterns of Patients with Local Allergic Rhinitis in Southern China.

BACKGROUND: Local allergic rhinitis (LAR) is characterized by the production of specific IgE (sIgE) in the nasal mucosa without evidence of systemic atopy. The characteristics of LAR in Caucasians have been well documented. LAR is understudied in China, with prevalence, patient demographics, symptomatology, and the allergen sensitization profile being poorly understood. The purpose of this study is to investigate the demographics, characteristics, and allergen sensitization profile of patients with LAR in Southern China. METHODS: A total of 194 patients with rhinitis and 13 healthy subjects were enrolled in the current study. The patients' demographic data, clinical history, and symptoms were recorded. Local and systemic sIgE to a wide panel of specific allergens were measured in the nasal secretion and serum samples. RESULTS: Among the rhinitis patients, 115 were classified as allergic rhinitis (AR; 59.3%), 15 as LAR (7.7%), and 64 as non-AR (33.0%). The demographic characteristics, duration, frequency, and severity of symptoms were similar, although LAR exhibited higher symptom scores for nasal itch. Monosensitization was the predominant pattern of sensitization in both AR (109 out of 115, 95%) and LAR (14 out of 15, 93%). House dust mite was the dominant allergen in AR patients (109 out of 115, 95%), while pollen was the dominant allergen in LAR patients (11 out of 15, 73%). CONCLUSION: The prevalence of LAR patients in Southern China was 7.7%. Pollen was the most common sensitizing allergen for the local LAR patients, which differs from Caucasian studies, in which house dust mite was the dominant sensitizing allergen. Monosensitization was the predominant pattern in both AR and LAR.

The European Survey on Adverse Systemic Reactions in Allergen Immunotherapy (EASSI): A paediatric assessment.

BACKGROUND: Safety data on 'real-life' allergen immunotherapy (AIT) in children and adolescents is usually extrapolated from studies in adults. METHODS: Patients aged 18 or under initiating aeroallergen AIT were evaluated in a prospective European survey. Patient profiles and systemic reactions (SRs) were recorded. Descriptive, univariate and multivariate analyses were used to identify risk factors for SRs. RESULTS: A total of 1563 patients (mean ± SD age: 11.7 ± 3.9 years; rhinitis: 93.7%; asthma: 61.5%; polysensitization: 62.5%) and 1578 courses of AIT were assessed. Single-allergen AIT was administered in 89.5% of cases (n = 1412; mites: 49%; grass pollen: 25.8%; tree pollen: 8.7%; Alternaria: 4.6%; dander: 0.8%; weed pollen: 0.6%). Subcutaneous AIT (SCIT) was used in 71.4% (n = 1127) of the treatments, including 574 (50.9%) with natural extracts. Sublingual AIT (SLIT) was used for the remaining 451 treatments (drops: 73.8%; tablets: 26.2%). The mean ± SD follow-up period was 12.9 ± 3.3 months. The estimated total number of doses was 19,669 for SCIT and 131,550 for SLIT. Twenty-four patients (1.53%) experienced 29 SRs. Respiratory (55.7%) and skin symptoms (37.9%) were most frequent. Anaphylaxis was diagnosed in 3 SRs (10.3%), and adrenaline was administered in 2 of these cases. In a univariate analysis, the risk of SRs was lower in mite-sensitized patients and higher in cases of pollen polysensitization (>3), grass pollen extracts and the use of natural extracts (vs. allergoids). CONCLUSIONS: In a real-life paediatric setting, AIT is safe. SRs are infrequent and generally not severe. Pollen polysensitization, grass pollen extracts and natural extracts (vs. allergoids) were risk factors for AIT-associated SRs.

[The clinical efficacy of allergen-specific immunotherapy with water-salt extracts and adjuvant allergens for atopic asthma with household sensitization]. / Klinicheskaia éffektivnost' allergenspetsificheskoi immunoterapii vodno-solevymi ékstraktami i ad''iuvantnymi allergenami pri atopicheskoi bronkhial'noi astme s bytovoi sensibilizatsiei.

AIM: To evaluate the clinical and economic efficiency of allergen-specific immunotherapy (ASIT); to comparatively analyze the efficiency of various therapy regimens for atopic asthma. SUBJECTS AND METHODS: The clinical and economic efficiency of asthma therapy using ASIT with water-salt allergen extracts or the adjuvant drug alustal 'mite allergen' and only with medicines were comparatively analyzed. The investigation enrolled 156 patients with mild and moderate atopic asthma, household allergy. In Group 1 (n = 57), ASIT was performed using the classical scheme by subcutaneous injection of house dust mite allergen (JSC 'I.I. Mechnikov Biomed', Russia). In Group 2 (n = 43), ASIT was conducted using the alustal 'mite allergen' (Stallergenes, France). Group 3 (n = 56) received only medical therapy. RESULTS: ASIT with both water-salt allergen extracts and the adjuvant allergen alustal is an effective treatment for mild and moderate atopic asthma. ASIT greatly reduces the need for anti-inflammatory treatment and the use of symptomatic drugs and improves the physical and psychoemotional indicators of quality of life in patients. The economic benefit of ASIT is delayed, but its use significantly reduces financing costs. CONCLUSION: ASIT is a reasonable, highly effective and ultimately cost-effective treatment in patients with atopic asthma. A variety of drugs for ASIT can choose schemes that are convenient and acceptable for each patient, which allows wider use of this treatment.

Evolution and predictive value of IgE responses toward a comprehensive panel of house dust mite allergens during the first 2 decades of life.

BACKGROUND: The evolution of the IgE response to the numerous allergen molecules of Dermatophagoides pteronyssinus is still unknown. OBJECTIVES: We sought to characterize the evolutionary patterns of the IgE response to 12 molecules of D pteronyssinus from birth to adulthood and to investigate their determinants and clinical relevance. METHODS: We investigated the clinical data and sera of 722 participants in the German Multicenter Allergy Study, a birth cohort started in 1990. Diagnoses of current allergic rhinitis (AR) related to mite allergy and asthma were based on yearly interviews at the ages of 1 to 13 years and 20 years. IgE to the extract and 12 molecules of D pteronyssinus were tested by means of ImmunoCAP and microarray technology, respectively, in sera collected at ages 1, 2, 3, 5, 6, 7, 10, 13, and 20 years. Exposure to mites at age 6 and 18 months was assessed by measuring Der p 1 weight/weight concentration in house dust. RESULTS: One hundred ninety-one (26.5%) of 722 participants ever had IgE to D pteronyssinus extract (≥0.35 kUA/L). At age 20 years, their IgE recognized most frequently Der p 2, Der p 1, and Der p 23 (group A molecules; prevalence, >40%), followed by Der p 5, Der p 7, Der p 4, and Der p 21 (group B molecules; prevalence, 15% to 30%) and Der p 11, Der p 18, clone 16, Der p 14, and Der p 15 (group C molecules; prevalence, <10%). IgE sensitization started almost invariably with group A molecules and expanded sequentially first to group B and finally to group C molecules. Early IgE sensitization onset, parental hay fever, and higher exposure to mites were associated with a broader polymolecular IgE sensitization pattern. Participants reaching the broadest IgE sensitization stage (ie, ABC) had significantly higher risk of mite-related AR and asthma than unsensitized participants. IgE to Der p 1 or Der p 23 at age 5 years or less predicted asthma at school age. CONCLUSIONS: Parental hay fever and early exposure to D pteronyssinus allergens promote IgE polysensitization to several D pteronyssinus molecules, which in turn predicts current mite-related AR and current/future asthma. These results might inspire predictive algorithms and prevention strategies against the progression of IgE sensitization to mites toward AR and asthma.

Real-Life Study for the Diagnosis of House Dust Mite Allergy - The Value of Recombinant Allergen-Based IgE Serology.

BACKGROUND: Dermatophagoides pteronyssinus is one of the most important perennial allergen sources worldwide. Molecular diagnostics using the commercially available major allergens (Der p 1 and Der p 2) in combination with Der p 10 do not detect house dust mite (HDM) sensitization in a number of cases when used alone. The objective was to evaluate the IgE reactivity profiles of these patients using an experimental immunoassay biochip. METHODS: Sera of HDM-allergic patients (positive skin prick test, CAP class ≥1 for allergen extract, and positive intranasal provocation) were tested for IgE antibodies against Der p 1, Der p 2, and Der p 10 by ImmunoCAP fluorescence enzyme immunoassay. Negatively tested sera were examined by an experimental chip containing 13 microarrayed HDM allergens. RESULTS: Of 97 patients tested, 16 showed negative results to Der p 1, Der p 2, and Der p 10. MeDALL chip evaluation revealed 5 patients monosensitized to Der p 23, and 11 patients were negative for all HDM MeDALL chip components. Seven sera were available for further testing, and 3 of them showed IgE reactivity to dot-blotted nDer p 1, and 2 reacted with high-molecular weight components (>100 kDa) in nitrocellulose-blotted HDM extract when tested with 125I-labeled anti-IgE in a RAST-based assay. The HDM extract-specific IgE levels of the 11 patients were <3.9 kU/l. CONCLUSIONS: Recombinant allergen-based IgE serology is of great value when conventional IgE diagnostics fails. Der p 23 is an important HDM allergen, especially when major allergens are negative. Therefore, it would be desirable to have Der p 23 commercially available. Further research concerning the prevalence and clinical significance of different HDM allergens is needed.

[Efficacy and economic evaluation of sublingual immunotherapy with Dermatophagoides farinae drops in patients with allergic rhinitis and allergic asthma].

Objective:To evaluate the efficacy and economics of sublingual immunotherapy (SLIT) with Dermatophagoides farinae drops in patients with allergic rhinitis and allergic asthma. Method:Two hundred and three patients (aged 4-60 yr) with allergic rhinitis and allergic asthma induced by house dust mites were retrospectively analyzed. Eighty-six patients were treated by SLIT with standardized Dermatophagoides farina drops and pharmacotherapy (SLIT group), while 117 patients were treated by standardized pharmacotherapy (drug group). Patients were followed up for 2 years with one visit in every 3 months. Total nasal syptom score (TNSS), total rhinitis medicine score (TRMS), daytime asthma syptom score (DASS), nighttime asthma syptom score (NASS), total asthma medicine score (TAMS) and treatment charge were recorded at each visit. Result:There was no significant difference between two groups in TNSS, TRMS, DASS, NASS, TAMS before treatment (all P>0.05). After 1-year or 2-year duration, there were significant differences between the SLIT group and drug group in TNSS, TMSS, DASS, NASS, TAMS (all P<0.01). After 1-year or 2-year duration, the symptom scores and medication scores of SLIT group significantly decreased compared with those before treatment (all P<0.01). In terms of treatment charge, although direct cost of SLIT group was a little higher than that of drug group, the indirect cost of SLIT group was remarkably lower than that of drug group, showing significant difference (P<0.01). Conclusion:SLIT with Dermatophagoides farinae drops is effective in patients with allergic rhinitis and allergic asthma, which may also reduce indirect cost.