Low Potency of Indian Dust Mite Allergen Skin Prick Test Extracts Compared to FDA-Approved Extracts: A Double-Blinded Randomized Control Trial.

BACKGROUND: Skin prick testing is the most important diagnostic tool to detect immunoglobulin E-mediated allergic diseases. With increase in the number of allergy tests performed in India, it is imperative to know the potency of indigenous extracts in comparison with U.S. Food and Drug Administration (USFDA)-approved extracts. METHODS: A randomized comparison trial of Indian manufactured and USFDA-approved extracts of Dermatophagoides pteronyssinus (DP) and Dermatophagoides farinae (DF) was done at Christian Medical College & Hospital, Vellore, India from April 2014 to June 2015, to compare the skin test reactivity of indigenous allergen extracts of dust mites against validated allergen. Study enrollment included 197 patients with allergic disorders that showed sensitivity to dust mite during routine allergy skin testing. Study participants were tested with varying dilutions of DP and DF indigenous extracts along with USFDA-approved allergens in a blinded fashion. Results were recorded, and statistical significance was calculated using the Friedman rank sum test. RESULTS: Using the Friedman rank sum test with a Tukey adjustment for multiple comparisons, we found that the extracts in each dilution were significantly different (P < .0001). The full strength indigenous extracts, B-DF (DF allergen standard extract from Bioproducts and Diagnostics, India) and C-DF (DF allergen extract from Creative Diagnostics, India) extracts, had mean wheal sizes of 7.69 (standard deviation [SD] 9.91) and 31.01(SD 51.04), respectively. The full strength S-DF (DF allergen extract from Jubilant Hollister Stier, Spokane, WA, USA) had a mean wheal size of 109.97 (SD 162.73), which was significantly higher (P < .0001) than both the indigenous extracts. For each of the dilutions, the S-DF mean wheal size was significantly greater than that of the corresponding B-DF and C-DF wheal sizes. The full strength indigenous C-DP (DP allergen extract from Creative Diagnostics, India) had mean wheal size of 39.37 (SD 51.74). The full strength standard S-DP (DP allergen extract from Jubilant Hollister Stier, Spokane, WA, USA) extract had a mean wheal size of 167.66 (SD 270.80), which was significantly higher (P < .0001) than the indigenous C-DP extract. Similar differences were seen across all dilutions. CONCLUSION: The indigenous extracts have significantly lower potency compared to USFDA-approved extracts; hence, there is an urgent need for policy makers to institute stringent criteria for standardization of antigens in India.

Dolichandrone platycalyx: New entomophilous pollen--A report on pollen sensitization in allergic individuals.

BACKGROUND: Dolichandrone platycalyx, commonly known as Nile trumpet tree, is believed to have originated in East Africa. However, this and the variants of this tree are found in Europe, Asia, and America (California and Florida). The tree mostly grows in tropical climates, but temperate species are also found. This study was designed to evaluate the allergenicity of D. platycalyx, one of the most common entomophilous avenue trees in Karnataka state, and to determine the pollen production of D. platycalyx. METHODS: All of the patients with allergic rhinitis and asthma attending a tertiary care center in South India during August 2007 to March 2008 underwent a detailed clinical evaluation and skin-prick testing to common allergens along with D. platycalyx. Control subjects without any symptoms of respiratory allergy also underwent skin testing. The pollen counts were determined for a mature unopened flower of D. platycalyx. RESULTS: A total of 317 subjects with respiratory allergy and 30 controls were included in the study. A significant percentage (16.1%) of patients evaluated were observed to be sensitive to Dolichandrone pollen extract by skin-prick testing, whereas none of the control subjects were found to be sensitized. D. platycalyx was the fourth most common sensitizer after Parthenium hysterophorus, Prosopis juliflora, and Artemesia vulgaris. D. platycalyx was found to be a moderate pollen producer at 66,000 pollens/flower. CONCLUSION: Sensitization to D. platycalyx is common in subjects with respiratory allergies. The clinical relevance of this sensitization and other entomophilous plants needs additional study.

Factors associated with non-adherence to specific allergen immunotherapy in management of respiratory allergy.

BACKGROUND: Non-adherence to specific allergen immunotherapy is a major hurdle faced by the allergist, contributing to poor clinical outcomes. OBJECTIVES: To assess the independent association of various factors with non-adherence to specific allergen immunotherapy. METHODS: Fifty consecutive (non-adherent) and control (adherent) subjects receiving specific allergen immunotherapy were included in the study and various factors related to non-adherence including socio-demographic, clinical and immunotherapy related variables were compared between the two groups by univariate and multivariate analysis. RESULTS: On univariate analysis, gender, allergic conjunctivitis, family history, progression of disease, perception of immunotherapy, medicine requirement, and the pattern of missed doses greater than two in the last 10, 20 and 30 doses were found to be significantly associated with non-adherence. On multivariate analysis, independent association was observed with allergic conjunctivitis, family history, perception of immunotherapy, missed doses greater than two in the last 10 doses of immunotherapy and medicine requirement. CONCLUSIONS: The independent factors associated with non-adherence may vary between different settings and countries. There is a need for developing individual case holding programmes to improve clinical outcomes in patients receiving specific allergen immunotherapy.

Time interval and the factors associated with the development of asthma in patients with allergic rhinitis.

Rhinitis and asthma commonly coexist and studies have shown a positive association between rhinitis and asthma in both atopic and nonatopic adults. Longitudinal studies have shown that in many cases rhinitis precedes the onset of asthma. The aims of this study were to study the time interval for the development of asthma after the onset of rhinitis, to determine the proportion of patients in whom rhinitis precedes asthma, and to study the factors associated with the development of asthma in patients with allergic rhinitis compared to patients who continue to have allergic rhinitis alone. This was a cross-sectional study done at a tertiary care allergy center in Mysore, South India. It included consecutive patients between 2004 and 2006 with allergic rhinitis and/or asthma. We used a structured questionnaire, clinical evaluation, spirometry, and skin-prick testing. A total of 1,141 subjects were included in the study. Among them, 700 had allergic rhinitis for varying intervals before developing asthma and 355 had rhinitis without asthma. In subjects aged 20 years or younger, logistic regression analysis confirmed an independent association with a family history of allergic rhinitis and sensitization to house dust mites as risk factors and ever-used nasal steroids as protective against developing asthma in subjects with allergic rhinitis. In subjects older than 20 years, a family history of allergic rhinitis, atopy, and sensitization to house dust mites and trees were risk factors and ever-user of nasal steroids was protective. Rhinitis often preceded asthma and a high proportion of patients, both children and adults, developed asthma within 2 years after the onset of rhinitis. A family history of allergic rhinitis, atopy, and sensitization to house dust mites and trees are associated with the development of asthma in patients with allergic rhinitis.

Chronic urticaria sera increase basophil CD203c expression.

BACKGROUND: Approximately 40% of patients with chronic idiopathic urticaria have antibodies to the alpha subunit of the high-affinity IgE receptor. CD203c is a basophil activation marker known to be upregulated by cross-linking of the FcepsilonRIalpha receptor and may serve as a useful marker to identify these patients. OBJECTIVE: The primary objective was to assess the affect of sera from patients with chronic idiopathic urticaria on basophil CD203c expression. Secondary objectives were to correlate CD203c expression with basophil histamine release and size of the autologous serum skin test and to determine whether the mechanism is mediated by an IgG antibody. METHODS: Sera were obtained from patients with chronic idiopathic urticaria and positive autologous serum skin test or negative autologous serum skin test and normal controls. Sera were incubated with donor whole blood. Activated basophils from whole blood were identified by flow cytometry on the basis of the presence of CD203c on high-expressing IgE positive cells. RESULTS: Incubation of donor basophils with sera from patients with chronic idiopathic urticaria and positive autologous serum skin test demonstrated significant upregulation of CD203c. IgG depletion of representative sera from patients with chronic idiopathic urticaria resulted in significant decrease in CD203c expression on donor basophils. CD203c expression correlated with basophil histamine release and the size of the autologous serum skin test. CONCLUSION: Sera from patients with chronic idiopathic urticaria and positive autologous serum skin test significantly upregulate basophil CD203c and correlate with basophil histamine release. CLINICAL IMPLICATIONS: This article describes an activation marker on basophils whose expression is increased by sera from patients with chronic idiopathic urticaria.

House dust mite sensitivity is a factor in chronic urticaria.

BACKGROUND: Chronic urticaria is one of the perplexing problems faced by clinicians. There are a few reports associating house dust mite sensitivity with chronic urticaria, based upon the patient's history as well as intradermal skin testing and in vitro analysis. AIMS: To investigate the possible association between house dust mite sensitivity and chronic urticaria. METHODS: In this case control study three groups of patients were enrolled. Group I: Chronic urticaria (73 subjects). Group II: Chronic urticaria with collateral allergic disorders (49 subjects). Group III: Normal subjects without chronic urticaria or other allergies (25 subjects). All the patients underwent skin prick testing with antigens of the house dust mite, Dermatophagoides pteronyssinus (DP) and Dermatophagoides farinae (DF), with positive and negative controls. RESULTS: Among the patients with chronic urticaria, 78/122 (64%) patients had skin sensitivity to house dust mites. Out of these, 39/73 (53%) had chronic urticaria alone and 39/49 (79%) had chronic urticaria with other associated allergies. Among the normal control subjects, 7/25(28%) reacted positively to house dust mites. CONCLUSION: This study suggests a possible association of house dust mite sensitivity with chronic urticaria.

Clinical study of yoga techniques in university students with asthma: a controlled study.

Adult asthmatics, ranging from 19 to 52 years from an asthma and allergy clinic in a university setting volunteered to participate in the study. The 17 students were randomly divided into yoga (9 subjects) and nonyoga control (8 subjects) groups. The yoga group was taught a set of breathing and relaxation techniques including breath slowing exercises (pranayama), physical postures (yogasanas), and meditation. Yoga techniques were taught at the university health center, three times a week for 16 weeks. All the subjects in both groups maintained daily symptom and medication diaries, collected A.M. and P.M. peak flow readings, and completed weekly questionnaires. Spirometry was performed on each subject every week. Analysis of the data showed that the subjects in the yoga group reported a significant degree of relaxation, positive attitude, and better yoga exercise tolerance. There was also a tendency toward lesser usage of beta adrenergic inhalers. The pulmonary functions did not vary significantly between yoga and control groups. Yoga techniques seem beneficial as an adjunct to the medical management of asthma.

The prevalence of Dermatophagoides mite allergen in Colorado homes utilizing central evaporative coolers.

OBJECTIVE: The prevalence of mite allergen was studied in homes in which the indoor relative humidity may be increased by use of an evaporative cooler. METHODS: Colorado homes in which central evaporative coolers are used and control homes were evaluated. ELISAs with monoclonal antibodies specific for Der p 1 and Der f 1 were performed on dust samples from each home in May and August. Indoor relative humidity and temperatures were recorded daily. RESULTS: May samples did not show significant levels of mite allergen ( < 2 micrograms/gm dust). Of the August samples, 48 of 95 samples from homes with evaporative coolers (50.5%) had levels of Der p 1 and Der f 1 of 2 micrograms/gm dust or greater, but only 5 of 95 control samples (5.2%) had levels of 2 micrograms/gm dust or greater (p < 0.00001). Twelve of 19 homes with evaporative coolers (63%) were positive for mite allergen. Five of 19 (26%) control homes were positive (p < 0.05). The homes with evaporative coolers had average indoor relative humidity of 51% or greater: control homes had average relative humidity of less than 45%. CONCLUSION: Altering the indoor environment by raising indoor relative humidity through use of evaporative coolers leads to conditions that may facilitate Dermatophagoides survival.