House dust mite fauna in the Klang Valley, Malaysia.

Allergy to house dust mites (HDM) is an important cause of asthma and rhinitis in Malaysia. This study was carried out to evaluate the dust mite fauna in the Klang Valley. Dust samples were collected from 20 houses from March 1994 to February 1995. Thirty-three dust samples from mattresses were examined monthly for the occurrence of HDM. A total of 22 species in 9 families of HDM was identified. The most common and densely populated species was Blomia tropicalis with an average density of 8,934 mites/g of dust. Dermatophagoides pteronyssinus was the next in abundance, followed by Malayoglyphus intermedius. All houses surveyed were found to be infested with HDM and every house had at least 6 species of HDM. B. tropicalis and D. pteronyssinus were found in all mattresses. HDM in the Klang Valley were found to be highly prevalent and present in high densities. In this study, counts of D. pteronyssinus was found to exceed the proposed exposure threshold of 500 mites/g dust, for triggering acute asthma. Although counts of B. tropicalis exceeded D. pteronyssinus, no conclusion could be made because there is currently no exposure threshold for triggering acute asthma, for this species. Monthly distribution of B. tropicalis and D. pteronyssinus showed 2 peaks and 4 peaks, respectively. The major peak for D. pteronysinus was in January 1995 whereas for B. tropicalis, the major peak was more variable and occurred between November 1994 to January 1995. Both the species showed minor peak in April 1994.     

屋尘螨对支气管上皮细胞通透性的影响

目的探讨屋尘螨对支气管上皮细胞通透性的影响。方法通过ELISA、荧光定量PCR检测屋尘螨刺激人的支气管上皮细胞后对血管内皮生长因子（VEGF）表达的影响,通过检测细胞的跨膜电阻了解屋尘螨对人的支气管上皮细胞通透性的影响。结果屋尘螨可以上调入的支气管上皮细胞VEGF的表达,且呈明显的时间依赖性和浓度依赖性,并与支气管上皮细胞的通透性呈正相关,VEGF的单克隆抗体可以明显阻断这一效应。结论屋尘螨通过上调VEGF的表达增加了对支气管上皮细胞的通透性。     

Serum IgE,Skin and Radioallergosorbent Tests for House Dust and Mites in Asthmatic Children

Thirty asthmatic children were given an intradermal skin test, total IgE measurements and the radioallergosorbent test (RAST) against house dust and house dust mites (Dermatophagoides pteronyssinus and Dermatophagoides farinae). Results of the intradermal skin test and RAST were highly positive with overall agreement in 95.6%.

The correlation coefficient between the total IgE and the RAST to house dust was 0.35 (p<0.05). There was no significant difference between the total IgE and the RAST to D. pteronyssinus and D. farinae (p<0.05). The highly significant correlation coefficient between house dust and house dust mites (D. farinae, p<0.0001; D. pteronyssinus, p<0.00001) was determined by RAST. House dust has been found to be the most important allergen in children in Taiwan. The role of mites as a possible allergen in house dust also showed a highly significant correlation in our study.     

Skin test hypersensitivity for childhood asthma in Istanbul during a period of 16 years

BackgroundFor diagnosis of allergic disorders, besides history and physical examination, many in vivo and in vitro laboratory tests are used. Skin prick test (SPT) is an easily performed and valuable test in children. Our aim was to evaluate the SPT results of asthmatic children according to age and gender, in Istanbul and its neighborhood, followed for a period of 16 years.Material and methodsConsecutive 5080 asthmatic children, aged 1 to 18 years, admitted to Pediatric Allergy Policlinics of Istanbul University Cerrahpasa Medicine Faculty from 1987 to 2003, were screened retrospectively for 10 frequently exposed allergens.Results3086 cases (61 %) had SPT reactivity for one and/or for multiple allergens; the SPT reactivity percentages of the exposed allergens was 50% (2554 cases) for house dust mites DP, 49% (2462 cases) for house dust mites DF, 15 % (784 cases) for cat dander, 10 % (525 cases) for dog dander, 4% (228 cases) for lamb wool, 10 % (504 cases) for wheat, 3% (162 cases) for egg white, 6% (345 cases) for hazelnut pollen, 6% (318 cases) for Candida Albicans, 6% (326 cases) for Aspergillus Fumigatus.ConclusionWhile house dust mites were determined as the predominant allergen for each age groups in this study, allergy against cat dander was the third important allergen in sequence, as cat is a domestic pet which is frequently kept at home in Turkey.     

屋尘螨对支气管上皮细胞通透性的影响

目的 探讨屋尘螨对支气管上皮细胞通透性的影响.方法 通过ELISA、荧光定量PCR检测屋尘螨刺激人的支气管上皮细胞后对血管内皮生长因子(VEGF)表达的影响,通过检测细胞的跨膜电阻了解屋尘螨对人的支气管上皮细胞通透性的影响.结果 屋尘螨可以上调人的支气管上皮细胞VEGF的表达,且呈明显的时间依赖性和浓度依赖性,并与支...     

Impacto del polvo sahariano en la incidencia de síndrome coronario agudo

Introduction and objectivesAsian desert dust has recently been recognized as a trigger for acute myocardial infarction. The inflow of dust from the Sahara into Spain impairs air quality due to an increase in particulate matter concentrations in the ambient air. The aim of the present study was to elucidate whether Saharan dust events are associated with the incidence of acute coronary syndrome (ACS) in patients living near North Africa, the major global dust source.MethodsWe prospectively collected data on hospitalizations due to ACS in 2416 consecutive patients from a tertiary care hospital (Canary Islands, Spain) from December 2012 to December 2017. Concentrations of particulate matter with an aerodynamic diameter 10 microns or smaller (PM₁₀) and reactive gases were measured in the European Air Quality Network implemented in the Canary Islands. We applied the time-stratified case crossover design using conditional Poisson regression models to estimate the impact of PM₁₀ Saharan dust events on the incidence of ACS.ResultsThe occurrence of Saharan dust events observed 0 to 5 days before the onset of ACS was not significantly associated with the incidence of ACS. Incidence rate ratios (IRR) of PM₁₀ levels 1, 2, 3, 4 and 5 days before ACS onset (for changes in 10 μg/m³) were 1.27 (95%CI, 0.87-1.85), 0.92 (95%CI, 0.84-1.01), 0.74 (95%CI, 0.45-1.22), 0.98 (95%CI, 0.87-1.11), and 0.95 (95%CI, 0.84-1.06), respectively.ConclusionsExposure to Saharan desert dust is unlikely to be associated with the incidence of ACS.     

Exposition and sensitization to Tyrophagus putrescentiae in a allergic population to Dermatophagoides pteronyssinus in Huelva, Spain

BackgroundIn this work we analyzed the allergological importance of Tyrophagus putrescentiae (Tp) in Huelva (SE Spain). We studied the level of exposition and the grade of sensitization to Tp in a group of patients sensitized to Dermatophagoides pteronyssinus (Dpt). The allergenic cross-reactivity between Dpt and Tp was determined by RAST inhibition.Methods and resultsWe analyzed house dust samples from the dwellings of allergic patients with documented Dpt sensitization. Skin test (ST), conjunctival provocation (CP) and/or specific IgE (RAST) to Tp were performed when Tp was identificated in the house dust sample of the patient. Among the 136 dust samples studied, Dpt was the most frequently identified mite species (94,8 %) and Tp was found in third position (41,1 %) after Glycyphagus domesticus (54,4 %). Among the 45 patients studied, 23 (51,1 %) presented, at least, two positive tests, 18 (40 %) were not sensitized to Tp and 4 (8,8 %) showed contradictory results. 26 patients (57,7 %) inhabited in urban areas and 19 (42,2 %) in rural regions. We determined specific IgE (RAST) to Tp in 25 patients, and the results were positive in 12, with only 7 with values greater than 2 kU/L. No significant correlation were found between IgE-antibody levels to Dpt and Tp. The RAST inhibition studies confirmed the low cross-reactivity between these mites and only in one patient Dpt partially inhibited the IgE-binding to Dpt extract.ConclusionsTp was the second more frequent storage mite in the house dust samples from patients allergic to Dpt in Huelva. However, only half of the exposed patients were sensitized to Tp and the majority inhabited in urban areas. No significant correlation were found between IgE-antibody levels to Dpt and Tp. The RAST inhibition studies confirmed the low cross-reactivity between these mites.     

House dust mites in Switzerland. III. Allergenic properties of the mites

The allergenic properties of the nine mite species prevalent in the house dust of northwestern Switzerland (Basel and surroundings) were studies. For the preparation of mite extracts, the average weight of each species was first determined and then the number per culture glass counted. Thus the extracts were prepared according to the weight of the mites. They were tested on 115 patients with ashma and/or rhinitis. Tests with patients own house dust and with a human dander/yeast mixture, which served as culture medium for the mites, were carried out simultaneously. Test results were either positive or negative for all substances in 93 patients (80 per cent). Dermatophagoides pteronyssinus, D. farinae and Euroglyphus maynei caused the most frequent and most severe reactions. The species Glycyphagus destructor, G. privatus, Chortoglyphus arcuatus, Gohieria fusca, Tyrophagus putrescentiae and Acarus siro seem to play a less important role, if any, in house dust allergies.     

北京地区尘螨过敏患者家庭螨类调查

目的调查北京地区尘螨过敏患者家庭螨类种类和比例,为北京地区尘螨防治提供理论依据。方法以北京协和医院就诊的38例北京地区尘螨过敏患者为研究对象,于2008年12月至2010年1月人户吸尘采集其所在家庭室内尘土样本,采用漂浮法收集尘土中的螨,分离制片,显微镜下分类计数并绘图。结果 38个家庭共采集样本345份,螨检出率为64.6%;经分离鉴定得出蜱螨亚纲3目12科15属22种,其中丝泊尘螨为我国致敏螨类一新纪录种;昆虫纲啮虫目1科1属2种。在分析的1798个标本中,主要致敏螨种前3位的依次为粉尘螨(62.46%),户尘螨(21.47%)和丝泊螨(5.28%)。对不同采集地点的调查结果表明,平房(91.1%)样本阳性率高于楼房(59.5%)。对不同生活环境螨密度的数据分析表明,枕头的平均螨密度最高,达到282只螨/克尘土,其次为床褥(120只螨/克尘土)和沙发(115只螨/克尘土)。平均螨密度在9至10月达最高峰,5至7月和12月至次年1月也出现2个高峰,3月和11月密度最低。结论本研究首次发现并报道了北京地区存在的丝泊尘螨,亦属于亚洲首次报道。北京地区室内优势螨种为粉尘螨,其次为屋尘螨和丝泊尘螨,平均螨密度在9至10月达最高峰。     

House dust mites in the city of Lima, Peru.

Since mites are the most common house dust allergens, knowledge about the species most prevalent in a region is important for diagnostic and specific immunotherapy purposes. In order to establish the prevalence of house dust mites in different city districts, 100 house dust samples were collected from different parts of Lima. Lima is a city of tropical climate located along the coast of the Pacific Ocean. The relative air humidity is 80-90% and the various districts studied are located at altitudes ranging from 37-355 meters. The mite Blomia tropicalis was the organism most frequently detected, being present in 59% of the house dust samples. Dermatophagoides pteronyssinus occupied second place (15.9%), followed by Chortoglyphus arcuatus and Tyrophagus putrescentiae. These four mites, taken together, represented more than 90% of the mites detected. No specimen of the species Dermatophagoides farinae was detected. We conclude that B. tropicalis and D. pteronyssinus are the most common house dust mites in Lima. Considering the high prevalence of B. tropicalis in Lima and the fact that its cross-reactivity with antigens of the mites of the family Pyroglyphidae is minimal, we conclude that sensitization to this mite should be investigated separately in allergic patients living in Lima.     

Safety profile and immunological response of dual sublingual immunotherapy with house dust mite tablet and Japanese cedar pollen tablet

BackgroundThere have been no studies of dual administration of sublingual immunotherapy (SLIT) tablets for perennial and seasonal allergic rhinitis. This trial (JapicCTI-184014) was conducted to investigate the safety profile and immunological response during dual therapy with SQ house dust mite (HDM) and Japanese cedar pollen (JCP) SLIT tablets.MethodsThis was a multicenter, open-label, randomized trial of 109 Japanese patients with coexisting HDM and JCP allergic rhinitis who had positive tests for HDM- and JCP specific IgE (≥0.7 kU/L). Patients were allocated to receive HDM (N = 54) or JCP (N = 55) SLIT tablets alone for 4 weeks followed by 8 weeks of dual therapy with both SLIT tablets administered within 5 min of each other. Adverse events (AEs), adverse drug reactions (ADRs), and serum IgE and IgG4 specific for HDM (Dermatophagoides farinae, Dermatophagoides pteronyssinus) and JCP were recorded.ResultsThe percentage of subjects with AEs and ADRs was similar between the two groups and between the two periods of monotherapy and dual therapy. Most AEs and ADRs were mild in severity, and no serious events were observed. The most common ADRs were local events in the oral cavity. Levels of IgE and IgG4 specific for HDM (D. farinae, D. pteronyssinus) and JCP were increased after treatment with HDM and JCP SLIT tablets, respectively.ConclusionsDual therapy with both SLIT tablets administered within 5 min after 4 weeks of monotherapy with HDM or JCP tablet was well tolerated and induced the expected immunological responses.     

Evaluation of the level of house dust mite allergens,Der p 1 and Der f 1 in Iranian homes,a nationwide study

BackgroundExposure to house dust mites (HDMs) is a major risk factor for the development of allergic symptoms. HDMs are worldwide in distribution. Assessing these allergens in each area is a critical step in evaluating the risk of sensitisation and controlling allergic symptoms. The aim of the present study was to evaluate the level of major HDMs, Der p 1 and Der f 1, in various parts of Iran.MethodsIn 2009, 257 dust samples were obtained from living rooms’ carpets in seven cities throughout Iran with different geoclimatic conditions. The level of Der p 1 and Der f 1 was measured by commercial ELISA.ResultsDetectable level of Der p 1 and Der f 1 levels were only found in Gorgan and Sari, two cities near the Caspian Sea with moderate temperatures and high relative humidity. In both of these cities, Der f 1 was more frequent than Der p 1 (100% vs. 85%) and was found to be at a higher level than Der p 1 (geometric mean 3128 vs. 439 ng/g dust, P < 0.001).ConclusionThe results of this study confirm that house dust mites in Iran are restricted to the Caspian Sea coastal areas, and in other parts, due to seasonal variations of temperature and humidity mites are not able to grow well and therefore are not an important risk factor for sensitisation and respiratory allergies.     

Bibliometric analysis of publications on house dust mites during 1980–2018

BackgroundThe global prevalence of allergic diseases has increased dramatically in recent years and are now recognized as significant chronic diseases worldwide. One of the most important allergens that causes allergic diseases is house dust mites.ObjectiveThis study aims to present a bibliometric overview of research published on dust mites between 1980 and 2018.MethodsArticles published from 1980 to 2018 were analyzed using bibliometric methods. The keywords “Dust mite*,” and “Dermatophagoides” were used in the Web of Science (WoS). Simple linear regression analysis was used to estimate the number of future publications on this subject.ResultsA total of 4742 publications were found, 2552 (53.8%) of them were articles. Most of the articles were on subjects related to immunology (1274; 49.9%) and allergy (1229; 48.1%). Clinical and Experimental Allergy (222; 8.7%) was the journal with the most publications. The USA was the country that most contributed to the literature with 461 (18.1%) articles. The countries producing the most publications on this subject were developed countries. The most active author was W.R. Thomas (66; 2.5%). The most productive institution was the University of Western Australia (91; 3.6%). The most cited article was published in the New England Journal of Medicine.ConclusionAccording to the findings, developed countries were the most productive in publishing on house dust mites. By planning multinational research rather than regional studies, it may be suggested that researchers in underdeveloped or developing countries could also conduct more research on this subject.     

不同浓度屋尘螨对Der p2基因修饰的树突状细胞表面分子的影响

目的 观察不同浓度屋尘螨(HDM)对HDM过敏原Der p2基因修饰的树突状细胞(DC)表面分子的影响.方法 以未转染DC为对照,不同浓度HDM处理HDM主要抗原基因Der p2转染的DC(Der p2-DC),培养72 h后流式细胞仪检测Der p2 DC表面共刺激分子CD80、CD86和MHCⅡ.结果 加入HDM后...     

Mite hypersensitivity in patients with rhinitis and rhinosinusitis living in a tropical environment

PurposeRhinitis and rhinosinusitis are major concerns in public health. Mites are important aetiological agents in the tropics. The present study investigated the in vivo response to mite allergens in patients with rhinitis and rhinosinusitis.MethodsAll patients with presumptive nasal allergy were included. Skin tests were done with inhalants and mite extracts. Patients were classified as allergic or non-allergic according to skin tests and history.ResultsOut of 229 patients, 175 (76.4%) showed positive skin tests. Allergic patients showed positivity to mites in 97.1% of cases, 51.4% to dog dander; 40.5% to cat dander; 36.5% to German cockroach; 22.8% to moulds; and 21.1% to grass pollens. Dermatophagoides farinae induced responses in 90.8% of patients, D. pteronyssinus in 90.1%, Blomia tropicalis in 74.8%, Glycyphagus domesticus in 62.2%, Chortoglyphus arcuatus in 58.2%, Acarus siro in 46.2%, Lepidoglyphus destructor in 35.4%, and Tyrophagus putrescentiae in 35.0%. Higher correlations were found between skin test diameters induced by mites from the same family.ConclusionsSensitisation to inhalant allergens is present in 76% of allergy clinics’ patients with rhinitis or rhinosinusitis. Our results confirm previous observations showing that mites constitute the most important cause of respiratory allergy in tropical settings and suggest that mite allergen cross-reactivity is responsible for the positivity of skin tests to mites not present in the patient's environment since the species Glycyphagus, Chortoglyphus, Acarus, Lepidoglyphus and Tyrophagus have not been found in Caracas house dust.     

Flagellated protozoa detected in Dermatophagoides by light microscopy

House dust mites (HDM) are arthropods of medical importance due to their relationship with allergic diseases. House dust provides a detrital habitat for these organisms, in which human skin scales are a primary food source. For digestion, wall gut cells elaborate potent proteases.Nevertheless, the observation of flagellated protozoa in intestinal extracts of HDM by light microscopy might contribute to digestive processes in mites, opening a new avenue of research regarding the ecological interactions between mites and these microorganisms in the utilisation of such substrates, as well as with regard to allergic diseases.     

不同浓度屋尘螨对Der p2基因修饰的树突状细胞表面分子的影响

目的 观察不同浓度屋尘螨(HDM)对HDM过敏原Der p2基冈修饰的树突状细胞(DC)表面分子的影响.方法 以未转染DC为对照,不同浓度HDM处理HDM主要抗原基因Der p2转染的DC(Der p2-DC),培养72 h后流式细胞仪检测Der p2-DC表面共刺激分子CD80、CD86和MHC Ⅱ.结果 加入HDM...