The role of worm infestation in allergic rhinitis.

The purpose of this study is to determine the relevance of the hygiene hypothesis; that is to determine if worm infestation has a protective role against the development of allergic rhinitis. A prospective case controlled study was conducted. Specific IgG levels to Toxocara were studied in 85 patients confirmed to have allergic rhinitis and were compared to levels in another 85 controls, with no form of allergy. The IgG assay was done using ELISA technique. There was a higher incidence of positive specific IgG to Toxocara in the controls as compared to allergic patients. The values were statistically significant [Chi square test (p=0.002)]. This negative association between worm infestation and allergic rhinitis suggests that a previous worm infestation could protect against the development of allergic rhinitis.

[Skin prick testing versus immumofluorescence testing for mites allergens].

OBJECTIVE: To discuss the characteristics of skin prick test (SPT) and immumofluorescence method (IFM) in detecting the atopy of dermatophagoides pteronyssinus (Dp) and dermatophagoides farinae (Df)and explore the relationship of them. METHOD: Four hundred and ninety-one patients with two or more symptoms of nasal obstruction,itching, sneezing and rhinorrhea received SPT and serum specific IgE detection using IFM. RESULT: SPT was more sensitive than IFM in detecting the atopy of Dp and Df (P < 0.05). If using the IFM as the gold standard, the sensitivity of SPT was all above 95% with the specificity a little bit lower than 80%. These two methods had a positive correlation in detecting the atopy of Dp and Df (r = 0.779, 0.776; P < 0.01). The sIgE concentrations of these two mites were highly correlated with each other (r = 0.954, P < 0.01), the SPT was highly correlated with each other (r = 0. 946, P < 0.01). CONCLUSION: SPT was more sensitive than IFM in detecting the atopy of Dp and Df. In most cases, SPT can replace IFM to detect patients' allergia on mites. Besides, it is good enough to detect either of the serum specific IgE concentrations of Dp and Df.

House dust mite avoidance measures for perennial allergic rhinitis.

BACKGROUND: This is an update of a Cochrane Review first published in The Cochrane Library in Issue 4, 2001 and previously updated in 2003 and 2007.It is estimated that in developed countries approximately 30% of the general population suffer from one or more allergic disorders, of which allergic rhinitis is particularly common. Perennial rhinitis is most often due to allergy to the house dust mite. In such patients house dust mite avoidance is logical, but there is considerable uncertainty regarding the efficacy and effectiveness of interventions designed to reduce dust mite exposure. OBJECTIVES: To assess the benefit (and harm) of measures designed to reduce house dust mite exposure in the management of house dust mite sensitive allergic rhinitis. SEARCH STRATEGY: Our search included the Cochrane Ear, Nose and Throat Disorders Group Trials Register, the Cochrane Central Register of Controlled Trials Register (CENTRAL) (The Cochrane Library Issue 4, 2009), MEDLINE and EMBASE. The date of the last search was 31 December 2009. SELECTION CRITERIA: Randomised controlled trials, with or without blinding, in which house dust mite control measures have been evaluated in comparison with placebo or other dust mite avoidance measures, in patients with clinician-diagnosed allergic rhinitis and confirmed allergy to dust mite. DATA COLLECTION AND ANALYSIS: Two authors independently screened titles and abstracts, graded methodological quality using the Cochrane approach and extracted data. Meta-analysis was neither possible nor appropriate due to heterogeneity of the patient groups studied. MAIN RESULTS: Nine trials involving 501 participants satisfied the inclusion criteria. Only two studies investigating the effectiveness of mite impermeable bedding covers were of good quality; the remaining seven studies were small and of poor quality. Two trials investigated the efficacy of acaricides, another two trials investigated the role of high-efficiency particulate air (HEPA) filters. One trial, using a factorial design, investigated the efficacy of both acaricide and house dust mite impermeable bedding covers in isolation and combination; the remaining four trials investigated the efficacy of bedroom environmental control programmes involving use of house dust mite impermeable bedding covers. Seven of the nine trials reported that, when compared with control, the interventions studied resulted in significant reductions in house dust mite load. Of the interventions studied to date, acaricides appear to be the most promising type of intervention, although the findings from these studies need to be interpreted with care because of their methodological limitations. House dust mite impermeable bedding as an isolated intervention is unlikely to offer clinical benefit. No serious adverse effects were reported from any of the interventions. AUTHORS' CONCLUSIONS: Trials to date have on the whole been small and of poor methodological quality, making it difficult to offer any definitive recommendations on the role, if any, of house dust mite avoidance measures in the management of house dust mite sensitive perennial allergic rhinitis. The results of these studies suggest that use of acaricides and extensive bedroom-based environmental control programmes may be of some benefit in reducing rhinitis symptoms and, if considered appropriate, these should be the interventions of choice. Isolated use of house dust mite impermeable bedding is unlikely to prove effective.

Association between previous enterobiasis and current wheezing: evaluation of 1018 children.

The aim of this study was to investigate the association between parasitosis and allergy. We surveyed all children aged 4-12 years living in poor hygienic conditions in a shantytown of Istanbul. After obtaining data from the International Study of Asthma and Allergies in Childhood (ISAAC) and an additional questionnaire, performing a skin-prick test (SPT), and determining total IgE, stool and perianal tape specimens were obtained from 1018 participating children. The prevalence of past episodes of wheezing, current wheezing, asthma, and rhinitis was 31, 14.6, 10.7, and 26.2%, respectively. Parasitosis was present in 49.1%, Enterobius vermicularis (23.3%), being the most common. A history of treatment for enterobiasis was present in 37%. Comparison of children with and without current enterobiasis revealed no significant difference in allergic manifestations and SPT results, except for serum total IgE level (p = 0.018), whereas children with previous enterobiasis were more likely to have current wheezing (p = 0.012). Current wheezers were more likely to have previous enterobiasis (p = 0.01) and a higher maternal employment level (p = 0.036) when compared with those without. According to logistic regression analysis, covariables significantly positively related with current wheezing were previous enterobiasis (p = 0.003) and being < or =5 years of age (p = 0.043), whereas being the first child of the family (p = 0.043) was negatively related. A previous infection with E. vermicularis was found to potentiate current wheezing in a population living in a shantytown in Istanbul.

Relationship between Toxocara seropositivity and allergic rhinitis.

BACKGROUND: Allergic rhinitis is the most common chronic disease in the upper respiratory tract, requiring better diagnostic methodology to counteract its onslaught. The purpose of this study was to investigate the association between Toxocara seropositivity and allergic rhinitis. METHODS: Sixty-four consecutive patients with allergic rhinitis and 61 healthy volunteers in the control group were included in this study. The diagnosis of allergic rhinitis was defined by positive epicutaneous prick test. The diagnosis of toxocariasis was established by IgG and specific IgE antibodies against Toxocara by ELISA method. All cases were examined for intestinal parasites also. The seropositive cases with Toxocara were reevaluated for symptoms and signs of toxocariasis. RESULTS: Higher toxocariasis seropositivity (ELISA IgG; 28.1%) rate was determined in the patients with allergic rhinitis and compared with the control groups (11.5%; p < 0.05). Specific IgE seropositivity (17.2%) was high for the patients with allergic rhinitis compared with the control group (3.3%; p < 0.05). CONCLUSION: Our results show that there was a possible causal relationship between Toxocara infection and allergic rhinitis. Patients with allergic rhinitis from a region with high prevalence for this parasitic infection should be evaluated for Toxocara infection.

House dust mite avoidance measures for perennial allergic rhinitis.

BACKGROUND: In developed countries, it is estimated that approximately 30% of the general population suffer from one or more allergic disorders, of which allergic rhinitis is the most common. Perennial rhinitis is most often due to allergy to the house dust mite. In such patients, house dust mite avoidance is logical, but there is considerable uncertainty regarding the efficacy and effectiveness of interventions designed to reduce dust mite exposure. OBJECTIVES: To assess the benefit (and harm) of measures designed to reduce house dust mite exposure in the management of house dust mite sensitive allergic rhinitis. SEARCH STRATEGY: Our search included the Cochrane Ear, Nose and Throat Disorders Group Trials Register, the Cochrane Central Register of Controlled Trials Register (CENTRAL) (The Cochrane Library, Issue 2, 2005), MEDLINE (1951 to 2005) and EMBASE (1974 to 2005). No restrictions on the language of publication were employed. The bibliography of each paper and other published reviews were checked for further references. The date of the last search was May 2005. SELECTION CRITERIA: Randomised controlled trials (with or without blinding), in which house dust mite control measures have been evaluated in comparison with placebo or other dust mite avoidance measures, in patients with clinician diagnosed allergic rhinitis and confirmed allergy to dust mite. DATA COLLECTION AND ANALYSIS: Two authors independently checked titles and abstracts identified by the searches and full text copies of all papers of potential relevance were considered. Trials were graded for methodological quality using the Cochrane approach. Data extraction was performed in a standardised manner. Meta-analysis was neither possible nor appropriate, because of the heterogeneity of the patient groups studied; a narrative overview of the results is therefore presented. MAIN RESULTS: Seven trials satisfied the inclusion criteria. Of these, only two studies investigating the effectiveness of mite impermeable bedding covers were of good quality; the remaining five studies were small and of poor quality. Two trials investigated the efficacy of acaricides, another two trials investigated the role of high-efficiency particulate air filters; the remaining three trials investigated the efficacy of bedroom environmental control programmes involving use of house dust mite impermeable bedding covers. Six of the seven trials showed that the interventions result in significant reductions in house dust mite load when compared with control. Of the house dust mite interventions studied to date, acaricides appear to be the most promising type of intervention, although the findings from the two studies which employed these interventions need to be interpreted with care because of their methodological limitations. Use of house dust mite impermeable bedding as an isolated intervention is unlikely to offer clinical benefit. No serious adverse effects were reported from any of the interventions. AUTHORS' CONCLUSIONS: Trials to date have on the whole been small and of poor methodological quality, making it difficult to offer any definitive recommendations on the role, if any, of house dust mite avoidance measures in the management of house dust mite sensitive perennial allergic rhinitis. The results of these studies suggest that use of acaricides and extensive bedroom based environmental control programmes may be of some benefit in reducing rhinitis symptoms and, if considered appropriate, these should be the interventions of choice. Isolated use of house dust mite impermeable bedding is unlikely to prove effective.

[Cloning, expression, purification and identification of Der f6 gene and its immunological characteristics from the dust house mite].

OBJECTIVE: To construct, purify and characterize a recombinant expression plasmid containing Der f6 gene of Dermatophagoides farinae. METHODS: A pair of primers was designed according to the known sequence of Der f6 gene. The live mites identified and cultured locally were picked and the total RNA was extracted. The Der f6 gene fragment was amplified by RT-PCR, and cloned into pMD18-T vector, and then transferred into E. coli Top10. The target gene obtained from the recombinant plasmid by digestion with EcoR I and Xho I was connected to the prokaryotic expression vector pET-24a. The expressed recombinant plasmid containing Der f6 gene was constructed by cloning target gene into pET-24a and first transferred into E. coli Top10, then into E. coli B121 (DE3). The expressed recombinant protein was analyzed by SDS-PAGE and Western blotting, and was purified by immobilized metal ion affinity chromatography (IMAC). RESULTS: The two recombinant plasmids, pMD18-T-Der f6 and pET24a-Der f6, were constructed. SDS-PAGE showed a correct molecular weight of the recombinant Der f6 protein. After purification by affinity chromatography, the protein showed only one strip on SDS-PAGE gel and appropriate combination ability with IgE in sera of allergic patients. CONCLUSION: The Der f6 gene has been cloned into plasmid pMD18-T vector and sub-cloned into the expression vector pET-24a, the recombinant plasmid pET24a-Der f6 has been expressed in E. coli BL21 (DE3), purified by IMAC, and showed appropriate IgE-combined ability.

Creating a dust-free environment.

Your doctor says you're allergic to dust mites, which explains your constant runny nose and watery eyes. You know the best way to prevent your allergy symptoms is to avoid their cause--dust. You've always tried to keep a clean house. What more can you do?

[Prevalence of respiratory and atopic disorders in Chinese school children].

OBJECTIVE: To compare the prevalence of respiratory and atopic disorders, and to assess the role of atopy in the development of asthma in Chinese school children from Beijing, Guangzhou, and Hong Kong. METHODS: Community-based random samples of school children aged 9 approximately 11 years from three Chinese cities (Beijing, Guangzhou and Hong Kong) were recruited for study using the International Study of Asthma and Allergies in Childhood (ISAAC) Phase II protocol. Subjects were studied by parental questionnaires (n = 10 902), skin-prick tests and skin examination (n = 3 479). RESULTS: The prevalence rates of current wheeze, speech limiting wheeze, rhinoconjunctivitis and flexural dermatitis were significantly higher in Hong Kong than in Beijing and Guangzhou. The atopy rate was also higher in Hong Kong (41.2%) than in Beijing (23.9%) and Guangzhou (30.8%). Atopy was strongly correlated with current wheeze (OR = 7.74; 95% CI = 5.70 approximately 10.51). Subgroup analyses of children from Hong Kong revealed that children born in mainland China who had subsequently migrated to Hong Kong had a significantly lower rate of allergic symptoms and atopy than those born in Hong Kong. CONCLUSION: The prevalence of asthma, allergic diseases and atopy was highest in school children from Hong Kong. Atopic sensitizations is an important factor associated with asthma in Chinese children.

House dust mite avoidance measures for perennial allergic rhinitis.

BACKGROUND: In developed countries, it is estimated that 15% of the general population suffer from one or more allergic disorders, of which allergic rhinitis is the most common. Perennial rhinitis is most often due to allergy to the house dust mite. In such patients, house dust mite avoidance is logical, but there is considerable uncertainty regarding the efficacy and effectiveness of interventions designed to reduce dust mite exposure. OBJECTIVES: To assess the benefit (and harm) of measures designed to reduce house dust mite exposure in the management of house dust mite sensitive allergic rhinitis. SEARCH STRATEGY: We searched the Cochrane Controlled Trials Register, Central, MEDLINE and EMBASE. No restrictions on the language of publication were employed. The bibliography of each paper and other published reviews were checked for further references. We wrote to first authors of all included trials in an attempt to identify further published and unpublished trials. SELECTION CRITERIA: Randomised controlled trial (with or without blinding), in which house dust mite control measures have been evaluated in comparison with placebo or other dust mite avoidance measures, in patients with clinician diagnosed allergic rhinitis and confirmed allergy to dust mite. DATA COLLECTION AND ANALYSIS: Two reviewers independently checked titles and abstracts identified by the searches and full text copies of all papers of potential relevance were considered. Trials were graded for methodological quality using the Cochrane approach. Data extraction was performed in a standardised manner. Meta-analysis was neither possible, nor considered appropriate, because of the heterogeneity of the patient groups studied; a narrative overview of the results is therefore presented. MAIN RESULTS: Four trials satisfied the inclusion criteria, all of which were small and of poor quality. Two trials investigated the efficacy of acaricides, a third investigated the role of high-efficiency particulate air (HEPA) filters, whilst a fourth investigated the efficacy of a bedroom environmental control program that comprised use of a barrier mattress cover, fortnightly washing of bed covers, removal of soft furnishings and daily cleaning. Each of the four trials showed the interventions to result in significant reductions in house dust mite load when compared with control. Trial results suggest that the interventions may be effective in reducing some rhinitis symptoms, though it is not possible to provide a reliable summary estimate about the magnitude of such symptom reduction. No serious adverse effects were reported from the interventions. REVIEWER'S CONCLUSIONS: Trials to date have been small and of poor methodological quality making it difficult to offer any definitive recommendations on the role, if any, of house dust mite avoidance measures in the management of house dust mite sensitive perennial allergic rhinitis. The results of these studies suggest that interventions designed to reduce house dust mite exposure in patients with house dust mite allergic perennial rhinitis may be of some benefit in reducing rhinitis symptoms. Data at present is only available for acaricides, HEPA filters and a bedroom-based environmental control program; therefore, if considered appropriate, these should be the interventions of choice.