Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “house dust mite”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed2003

Quantitation of house dust mites and house dust mite allergens in the microenvironment of dogs.

OBJECTIVE: To quantitate the density of Dermatophagoides farinae and D pteronyssinus and concentrations of house dust mite (HDM) allergens (Der f 1, Der p 1, and Group 2 allergens) in the indoor microenvironment of dogs. Sample Population-50 homes in Columbus, Ohio. PROCEDURES: n each home, samples of dust were collected from 3 locations in which dogs spent most time. Whenever possible, the species of mites collected was identified. Mite density (mites/g of dust) was assessed, and allergen concentrations were assayed by standardized ELISAs. Relative humidity and temperature in each home were monitored during a 5-day period. Characteristics of homes and sample sources were evaluated. RESULTS: Dust samples from all 50 homes contained > or = 1 HDM allergen; Der f 1 and Der p 1 were detected in 100 and 74% of homes, respectively. Fifteen homes had HDMs; compared with D pteronyssinus, D farinae was found more commonly (14/15 homes) and at a higher density. Basements, homes without central air-conditioning, and dog beds that were > or = 1 year old had high HDM allergen concentrations. Homes with > or = 2 microg of Der f 1 or Group 2 allergens/g of dust or > or = 100 mites/g of dust were significantly more likely to have a maximum relative humidity > or = 75%. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicate the presence of HDMs and HDM allergens in the specific microenvironment of dogs in homes. Factors associated with high levels of exposure were identified, which may be associated with increased risk for sensitization and development of atopic diseases.

Allergens↗
PubMed2003

Quantitation of house dust mites and house dust mite allergens in the microenvironment of dogs.

OBJECTIVE: To quantitate the density of Dermatophagoides farinae and D pteronyssinus and concentrations of house dust mite (HDM) allergens (Der f 1, Der p 1, and Group 2 allergens) in the indoor microenvironment of dogs. SAMPLE POPULATION: 50 homes in Columbus, Ohio. PROCEDURES: In each home, samples of dust were collected from 3 locations in which dogs spent most time. Whenever possible, the species of mites collected was identified. Mite density (mites/g of dust) was assessed, and allergen concentrations were assayed by standardized ELISAs. Relative humidity and temperature in each home were monitored during a 5-day period. Characteristics of homes and sample sources were evaluated. RESULTS: Dust samples from all 50 homes contained > or = 1 HDM allergen; Der f 1 and Der p 1 were detected in 100 and 74% of homes, respectively. Fifteen homes had HDMs; compared with D pteronyssinus, D farinae was found more commonly (14/15 homes) and at a higher density. Basements, homes without central air-conditioning, and dog beds that were > or = 1 year old had high HDM allergen concentrations. Homes with > or = 2 microg of Der f 1 or Group 2 allergens/g of dust or > or = 100 mites/g of dust were significantly more likely to have a maximum relative humidity > or = 75%. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated the presence of HDMs and HDM allergens in the specific microenvironment of dogs in homes. Factors associated with high levels of exposure were identified, which may be associated with increased risk for sensitization and development of atopic diseases.

Allergens↗
PubMed1971

High altitude and house-dust mites.

House dust from high mountainous areas of Switzerland contains very few house-dust mites. In contrast to lower-lying regions, only very small quantities of house-dust allergen are found at high altitudes.The cause of this phenomenon seems likely to be the climatic conditions in the high mountains of Europe, where cold air leads to extremely low humidity levels indoors. The soil conditions and a type of construction providing good protection against the penetration of water also contribute to dry conditions in houses. These factors prevent the development of large populations of allergen-producing house-dust mites.The beneficial effect of a stay at high altitudes on patients with atopic asthma is probably due to the low concentrations of house-dust allergen.

Altitude↗
PubMed1991

[Correlation between nasal polyposis and perennial allergy exemplified by house dust mite and house dust allergy].

A total of 139 patients with nasal polyps were investigated by a standardized history, intradermal skin test and nasal challenge to house dust mite allergy. The aim of the study was to assess the disputed role of perennial allergy in patients with nasal polyps using allergens to the house dust mite as an example. Using our diagnostic criteria we found allergy to house dust mite in 28% of all cases. We found this diagnosis in 44.8% of patients aged 10-39. We recommend, especially in this age group, an allergy test, if necessary with the appropriate therapy. Test correlations are illustrated in 174 patients who have been examined by the above methods. Good reproducibility was found by the nasal challenge, which led to the right diagnosis in 92%, compared with 81% by a standardized history. Therefore, it can be considered to be the key to the diagnosis of allergy.

Adolescent↗
PubMed2004

Permeability of synthetic and feather pillows to live house dust mites and house dust.

BACKGROUND: Previous studies have demonstrated significantly higher house dust mite (HDM) allergen levels from synthetic pillows, compared to feather pillows. Reasons for these differences could be lower permeability of feather pillow coverings to allergen in dust, greater HDM penetration of synthetic pillow covering, or both. OBJECTIVES: To determine the permeability of synthetic and feather pillow coverings to live HDMs and house dust. METHODS: Twenty live adult HDMs were seeded on top of two types of synthetic pillow covering (one standard polyester and one newer polyester/cotton type) and one type of feather pillow coverings with adequate food supply below in sealed culture dishes, kept at 23 degrees C and 70% relative humidity. After 24 and 48 h live HDM numbers remaining on top of the coverings were enumerated microscopically. Three aliquots of fine house dust (each in triplicate) were placed on top of the synthetic and feather pillow coverings, shaken gently for 30 min and penetrated dust was collected and weighed. RESULTS: After 24 h, all 20 HDMs had penetrated the standard synthetic pillow coverings, and no HDMs had penetrated either the feather pillow or the new synthetic pillow coverings after 24 or 48 h. Dust permeability (% of applied dust) for the standard synthetic, new type synthetic and feather pillow coverings were 0.88%, 0.07%, and 0.07%, respectively. This compared to 0.02% for a commercial occlusive pillow cover. CONCLUSIONS: These findings of total permeability of standard synthetic pillow coverings to live HDMs, and their greater permeability to house dust could explain their reported higher HDM allergen levels, compared to feather pillow coverings. Newer types of synthetic pillow coverings are similar to feather pillow coverings in their permeability to live HDMs and house dust.

Allergens↗
PubMed2006

[Evaluation of the prevalence of house dust mites in house dust sent to the Adnan Menderes University Medical Faculty Parasitology Laboratory].

House dust is composed of remnants and particles of many kinds of animate and inanimate materials. It has been reported that the most common allergens in house dust are mites that cause allergic rhinitis, asthma, atopic dermatitis, and seasonal keratoconjunctivitis. The aim of this study was to determine the prevalence of house dust mites in dust specimens sent to our laboratory from November 2002-May 2004. Specimens were evaluated using the flotation concentration method in the first, fourth and 24th hours. Out of 88 specimens, mites were detected in 20 (22.72%). In addition Enterobius vermicularis eggs were found in two specimens.

Allergens↗
PubMed1976

House dust mite and house dust allergy.

Skin testing and the radioallergosorbent test (RAST) with extracts of house dust and mite (D. farinae) were performed on 100 patients. Correlation between positive prick tests with the two antigens was low, many more reactions being obtained with the house dust antigen in patients clinically positive to house dust. Also, for both antigens, the degree of reactivity was higher with the prick test than with RAST. It is concluded that, in this geographic area, house dust extract is more suitable than mite extract for skin testing and, by inference, for hyposensitization therapy of house dust-sensitive patients.

Adolescent↗
PubMed2004

The clinical effect of environmental control of house dust mites in 60 house dust mite-sensitive dogs.

The purpose of this study was to evaluate the effects of benzyl benzoate, an acaricide for the control of house dust mites, in 60 house dust mite-sensitive dogs. All dogs showed positive reactions on intradermal skin testing for house dust mites (Dermatophagoides farinae, Dermatophagoides pteronyssinus) alone, or house dust mites with storage mites (Acarus siro, Tyrophagus putrescentiae, Glycophagus domesticus). House dust samples from the owners' houses were collected and sent to the clinic, where the authors performed a test (Acarex test) to semi-quantify the amount of guanine, a house dust mite product. Treatment with benzyl benzoate was repeated until the house dust samples were negative for house dust mite guanine. After treatment, 29 out of 60 house dust mite-sensitive dogs (48%) showed no skin lesions or pruritus. Moderate results were achieved in 22 dogs (36%), with reduced pruritus and minimal skin lesions, but still requiring medication. In 13 dogs, this involved regular treatment (3-4 times a year) with antibiotics and anti-yeast medication, and in eight dogs, immunotherapy was used. One dog was controlled with essential fatty acids as monotherapy and one dog was controlled with immunotherapy and essential fatty acids. In the remaining nine dogs (15%), the pruritus remained the same, and these dogs were controlled with oral corticosteroids. These results indicate that house dust mite elimination is a useful tool in the management of house dust mite-sensitive dogs.

Animals↗
PubMed1997

The Melbourne house dust mite study: eliminating house dust mites in the domestic environment.

BACKGROUND: Hypersensitivity to house dust mite allergens is associated with increased asthma morbidity. Asthma severity appears to be related to the degree of mite allergen exposure. Short-term studies suggest that complete avoidance reduces disease severity. OBJECTIVE: The study was designed to assess the effect of different mattress covers and floor coverings on mite allergen concentrations in the homes of mite-sensitive children with asthma in the city of Melbourne, Australia. METHODS: Mite allergen Der p 1 concentration was measured on mattress covers, mattress surfaces, and carpeted and uncarpeted floors in 107 dwellings; and measurement was performed on three occasions over a 5-month period. After the first sampling, all mattress covers and impermeable encasements were permanently removed. RESULTS: The initial geometric mean concentrations of Der p 1 (micrograms per gram of fine dust) from the surfaces of sheepskin, wool, and cotton mattress coverings were greater than those from the surfaces of impermeable mattress encasements (116, 113, and 19 vs 0.4) (p < 0.001); corresponding concentrations on the underlying mattresses were 142, 38, 20, and 0.6, respectively (p < 0.05 to 0.001). At the end of the study these mattress surface concentrations were 79, 65, 9.7, and 3.1, respectively. In 24 dwellings an uncarpeted room was adjacent to a carpeted room. At each visit the concentration of Der p 1 in uncarpeted rooms was below the reported threshold for sensitization and significantly less than that in the adjacent carpeted room. CONCLUSION: In homes of children with asthma, "asthmogenic" concentrations of Der p 1 were found on nonencased mattresses and carpeted floors, but the use of impermeable mattress encasements and carpet exclusion were associated with concentrations of Der p 1 below the reported threshold for sensitization.

Adolescent↗
PubMed2003

Distribution of house dust mite allergen: comparing house dust mite allergen levels in dust samples collected from different sites on living room floors with smooth coverings.

BACKGROUND: The distribution of house dust mite allergen (Der p1) in living rooms with smooth floor coverings, as measured in the middle compared with the border of the floor was investigated. It was hypothesized that activity causes displacement of Der p1, from the middle towards the border. METHODS: Dust samples from the middle and border of 50 floors with smooth coverings were collected and analysed on Der p1 content in a standardized way. RESULTS: The Der p1 exposure expressed as per unit area (ng/m2) showed that border samples contained significantly more Der p1 compared with middle samples (median: 2.57 vs 0.27, respectively, P = 0.023). Presence of pets and presence of more than two inhabitants increased the difference. When expressed as per unit weight of dust (ng/g), significant differences were only detected when comparing Der p1 content of samples collected in households with three or more inhabitants [median: 2 (border) vs 53 (middle), respectively; P = 0.035]. CONCLUSIONS: The Der p1 is unequally distributed on living room floors with smooth coverings, most likely because of displacement of dust from the middle towards the border due to activity. Expression as ng/g of dust and ng/m2 could not obviously be interchangeable.

Animals↗
PubMed2000

House dust mite control measures for asthma.

BACKGROUND: The major allergen in house dust comes from mites. Chemical, physical and combined methods of reducing mite allergen levels are intended to reduce asthma symptoms in people who are sensitive to house dust mites. OBJECTIVES: The objective of this review was to assess the effects of reducing exposure to house dust mite antigens in the homes of mite-sensitive asthmatics. SEARCH STRATEGY: We searched the Cochrane Airways Group trials register, checked reference lists of articles and hand-searched Respiration (1980 to 1996) and Clinical and Experimental Allergy (1980 to 1996). SELECTION CRITERIA: Randomised trials of mite control measures in asthmatic people known to be sensitive to house dust mites. DATA COLLECTION AND ANALYSIS: Two reviewers applied the trial inclusion criteria and extracted the data independently. One reviewer applied the trial quality assessment criteria. Study authors were contacted to clarify information. MAIN RESULTS: Twenty-three trials were included, with four trials awaiting assessment. There was little difference in improvement of asthma between people in experimental groups compared to control groups (odds ratio 1.2, 95% confidence interval 0.66 to 2.18). Asthma symptom scores were also similar for the experimental and control groups (standardised mean difference -0. 06, 95% confidence interval -0.54 to 0.41). These scores showed a high degree of heterogeneity. No significant difference was noted for medication usage (standardised mean difference -0.14, 95% confidence interval -0.43 to 0.15). Peak flow in the morning showed no significant difference between the experimental and the control groups (standardised mean difference -0.03, 95% confidence interval -0.25 to 0.19). REVIEWER'S CONCLUSIONS: Current chemical and physical methods aimed at reducing exposure to house dust mite allergens seem to be ineffective and cannot be recommended as prophylaxis for mite sensitive asthmatics.

Allergens↗
PubMed2000

Reactivity to intradermal injection of extracts of Dermatophagoides farinae, Dermatophagoides pteronyssinus, house dust mite mix, and house dust in dogs suspected to have atopic dermatitis: 115 cases (1996-1998).

OBJECTIVE: To compare reactivities to intradermal injection of extracts of Dermatophagoides farinae, Dermatophagoides pteronyssinus, house dust mite mix, and house dust in dogs suspected to have atopic dermatitis. DESIGN: Retrospective study. ANIMALS: 115 dogs. PROCEDURES: Records of all dogs suspected to have atopic dermatitis that underwent intradermal testing between October 1996 and July 1998 were reviewed. Reactivities to intradermal injection of crude mixed house dust mite (1:25,000 wt/vol) and crude house dust (25 PNU/ml) extracts were compared with reactivities to intradermal injection of individual extracts of D farinae and D pteronyssinus (1:50,000 wt/vol). RESULTS: Ninety dogs were confirmed to have atopic dermatitis including 61 of the 69 dogs with positive reactions to either or both of the individual house dust mite extracts. Intradermal testing with the mixed house dust mite extract had sensitivity of 75%, specificity of 96%, and accuracy of 83%. Intradermal testing with the house dust extract had sensitivity of 30%, specificity of 93%, and accuracy of 56%. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that use of crude mixed house dust mite and crude house dust extracts for intradermal testing in dogs is not as accurate a method of determining house dust mite hypersensitivity as is the use of individual D farinae and D pteronyssinus extracts mainly because of the high percentage of false-negative results. Extracts of individual house dust mites are recommended for intradermal testing of dogs suspected to have atopic dermatitis.

Allergens↗
PubMed1990

Mite allergy and exposure to storage mites and house dust mites in farmers.

Sensitization to house dust mites, storage mites and other common inhalation allergens was studied in 144 farmers using SPT and RAST. The study population was selected from a random sample of 808 farmers and consisted of 47 persons who had declared themselves to suffer from asthma, 63 persons who had reported respiratory symptoms, and 34 healthy persons without respiratory symptoms. The most prevalent RAST was towards storage mites and was found in 17% of farmers who suffered from asthma and was estimated to occur in 5% of the random sample of farmers. A positive RAST to house dust mites was found in 17% of farmers who reported to suffer from asthma. Sensitization to pollens, animal dander and grain species was rare. A positive RAST to moulds was not found. There was a strong association between a positive RAST to house dust mites and a positive RAST to storage mites (odds ratio 21.0). A positive RAST to storage mites was significantly associated with living in a dwelling in the past which was recalled as damp (odds ratio 4.9). A high number of house dust mites was found in nearly all dwellings (median count 148 mites/0.1 g dust) and a high number of storage mites was found in some dwellings. This study suggests that in humid and temperate regions of Europe, allergy to storage mites in farmers is not caused exclusively by occupational exposure but damp housing conditions and indoor exposure to storage mites may also be important.

Agriculture↗
PubMed1997

Seasonal variation of skin reactivity and specific IgE antibody to house dust mite.

BACKGROUND: House dust mite is an important cause of bronchial asthma worldwide. While the allergen is present all year-round, a seasonal variation of house dust mite allergen levels has been found. There have been few reports, however, on seasonal variation of specific immune response to house dust mite. OBJECTIVE: We studied the changes in skin reactivity and specific IgE antibody to house dust mite associated with seasonal variation of house dust mite allergen levels in houses of mite-sensitive asthmatic patients. METHODS: In 14 mite-sensitive asthmatic patients, house dust mite allergen (Der f 1) contents in bedding were measured monthly. Skin reactivity on prick test and specific IgE antibody to house dust mite, Dermatophagoides farinae (D. farinae), were determined every 3 months from july to December. RESULTS: The concentration of Der f 1 in dust from bedding reached maximum levels in August and September, and significantly decreased in November and December compared with August and September (P < .05). Skin reactivity (a ratio of mean wheal diameter of allergen to histamine) to D. farinae decreased significantly in December compared with September (P < .05). Serum levels of total IgE and specific IgE antibody to D. farinae decreased significantly in December compared with September (P < .05). CONCLUSION: These findings suggest that seasonal changes in natural exposure to house dust mite allergen might lead to concurrent changes in skin reactivity and specific IgE antibody to house dust mite in mite-sensitive asthmatic patients.

Adolescent↗
PubMed2003

Enhanced expression of B7.2 (CD86) by percutaneous sensitization with house dust mite antigen.

House dust mite antigen is a well-known allergen in the pathogenesis of atopic dermatitis (AD), a chronic relapsing inflammatory skin disease. We evaluated the AD model mice sensitized with house dust mite antigen and observed a Th2-dominant immune response. In this experiment, BALB/c mice were sensitized percutaneously with house dust mite antigen three times with 7 days interval after skin barrier disruption. A remarkable infiltration of polymorphonuclear granulocytes and monocytes in the cutis was observed in mice treated with this antigen, high serum IgE levels and IL-4 mRNA expression in local lymph node cells was also observed. CD19(+) B cell numbers overturned to CD4(+) helper T cells. In these mice, there was significant increase of B7.2 (CD86) expression on CD19(+) B cells. These results indicate that house dust mite antigen sensitizes BALB/c mice and skews their Th1/Th2 balance toward Th2.

Administration, Cutaneous↗
PubMed1977

[The importance of house dust mites and stored food mites as house dust allergens in the rural population].

House dust samples from rural districts contain more mite species (in particular stored food mites) than samples from urban areas, and the total number of mites is also approximately three times greater. 77 patients from rural districts, 48 of whom allergic to their own house dust, and 29 controls, were tested with mite extracts from Dermatophagoides pteronyssimus, D. farinae, Chortoglyphus arcuatus, Acarus siro, Glycyphagus destructor and Tyrophagus putrescentiae, and a house dust extract. Out of 32 patients who showed positive scratch tests to one or more mite extracts, 29 (90,6 percent) reacted positively to D. pteronyssimus, 25 (78.1 percent) to D. farinae and from 7 to 12 (20-40 percent) to the stored food mites. Out of the 48 patients allergic to their own house dust, 27 (56.2 percent showed positive reactions to D. pteronyssinus, 24 (50.0 percent) to the house dust extract and 21 (43.7 percent) to D. farinae. Only 5 (17.2 percent) out of the 29 controls reacted positively to one or more of the solutions tested. The stored food mites showed 2.5 to 4.5 times more positive reactions in the rural patients compared with the results obtained in urban patients. The importance of these mites in the sensitization of patients from rural districts is discussed.

Adolescent↗