Serodominance Profile in a Dust Mite Complex Region.

BACKGROUND/OBJECTIVE: The objective of this study was to describe the molecular sensitization profile of mite allergy in an area with a high environmental exposure of house dust mites (HDM) and storage mites. METHODS: Skin prick tests were performed with standardized extracts (DIATER, Madrid, Spain). A specific commercial molecular panel (MADx) for Dermatophagoides pteronyssinus (Dpt), Dermatophagoides farinae (Dfar), Lepidoglyphus destructor (Ldt), Tyrophagus putrescentiae (Tput), and Blomia tropicalis (Blot) was correlated with clinical parameters in Galician (northwestern of Spain) HDM allergic patients. RESULTS: Fifty patients (60% female) met the inclusion and exclusion criteria. All of the patient's present rhinitis (50), 28% (14) rhinitis and asthma, and 18% (9) atopic dermatitis (AD). Hundred patients had a positive prick test for Dpt, followed by Dfar (92%), Ldt and Tput (74%), and Blot (68%). More than 50% recognized specific IgE for Der p 1, Der p 2, reaching 86% in the case of Der p 23. No statistically significant differences in IgE levels were found between patients with/without asthma and those with mild or moderate-severe rhinitis. Der p 7 was higher among rhinitis patients (p value 0.05). AD relative risk (RR) was increased in patients sensitized to Der f 2, Der p 2, and Der p 23. Der p 10 decreases the risk to have AD (RR 0.80). CONCLUSION: The evaluation of IgE results in a comprehensive panel of allergens allows differentiation of serological reactivity profiles with their clinical expression, to perform an optimal management. Improvements in component resolved diagnosis and more research on the clinical relevance of mite allergens are needed to achieve a genuine diagnosis leading to specific immunotherapy.

Seafood hypersensitivity in mite sensitized individuals: is tropomyosin the only responsible allergen?

BACKGROUND: Seafood allergy has been related to mite sensitization, mainly mediated by the muscle protein tropomyosin. OBJECTIVES: To determine the correlation between seafood hypersensitivity and mite sensitization (Dermatophagoides pteronyssinus and Chortoglyphus arcuatus, a highly prevalent storage mite in Spain) and to investigate the implication of tropomyosin in cross-reactivity. METHODS: Patients from Northwest Spain were divided into 2 groups. The mite-seafood group contained 30 allergic mite individuals with a clinical history of food hypersensitivity. The mite group contained 40 individuals with positive skin prick test results to D pteronyssinus and C arcuatus but negative seafood test results. Specific IgE (sIgE) to whole mite and shrimp extracts, mite tropomyosin (rDer p 10), and shrimp tropomyosin (rPen a 1) were determined in each serum sample. Allergenic profiles were analyzed by immunoblot. Cross-reactivity studies were investigated by enzyme-linked immunosorbent assay and immunoblot inhibition studies. RESULTS: In the mite-seafood group, 71% of patients had positive sIgE results to shrimp and 55% of them to shrimp tropomyosin. A strong correlation was found between sIgE to shrimp tropomyosin and mite tropomyosin. Positive correlation was observed between sIgE to shrimp tropomyosin and severity of symptoms. In the mite group, none of the 20% of patients with sIgE to shrimp tested positive to shrimp tropomyosin. In the immunoblot inhibition experiment, the shrimp extract was totally inhibited by mite extract. These data suggest that primary sensitization is related to mite sensitization. CONCLUSION: Tropomyosin does not seem to be the main allergen involved in mite-seafood sensitization in mite sensitized individuals. High levels of sIgE to tropomyosin seem to be related to severity of symptoms.

Occupational respiratory allergy to roe deer.

BACKGROUND: Although scattered reports have been published on roe deer allergenicity, no systematic studies of allergenicity or possible cross-reactions have appeared. OBJECTIVES: To describe 2 patients with occupational roe deer allergy, demonstrated by positive skin and conjunctival provocation test results, and to note cross-reactions to other animal (mainly cow) allergens. METHODS: Two workers at animal rehabilitation centers were sensitized to roe deer. One patient had a history of rhinoconjunctivitis and the other a history of rhinoconjunctivitis and probable asthma. Both patients underwent skin testing with a standard battery of inhaled and epithelial allergens and with roe deer hair and dander extract and conjunctival provocation tests with roe deer hair extract. Immunodetection for IgE (both patients) and IgE immunoblot inhibition tests to determine inhibitory effect (1 patient) were also performed. RESULTS: The results of skin tests and conjunctival provocation tests showed that both patients were sensitized to roe deer allergens. In one patient specific IgE to roe deer extract was detected, and this extract completely inhibited IgE binding to cow hair and dander extract in immunoblotting tests. Specific IgE to roe deer proteins could not be demonstrated in the other patient. CONCLUSIONS: Our results suggest that roe deer epidermal derivatives can cause occupational respiratory disease in exposed workers and that allergy to this species should be considered in individuals who present with similar symptoms and exposure histories. Immunoblot inhibition studies suggested the possibility of cross-reaction between roe deer proteins and cow proteins.

In vivo and in vitro allergenicity of the domestic mite Chortoglyphus arcuatus.

BACKGROUND: Chortoglyphus arcuatus is frequently identified in mattress dust samples in coastal areas of northern Spain. OBJECTIVES: To establish the prevalence of positive skin test reactions to C. arcuatus and to analyze its allergenicity and cross-reactivity. METHODS: One hundred thirty-eight consecutive patients entered the study. The main referred symptoms were rhinoconjunctivitis and asthma. Skin tests were performed with extracts of Dermatophagoides pteronyssinus, Lepidoglyphus destructor, Tyrophagus putrescentiae, C. arcuatus, and Glycyphagus domesticus. Enzyme-linked immunosorbent assay inhibition experiments were conducted with the different mite species and immunoblots with serum samples from 31 sensitized patients. Conjunctival provocation tests were performed in 10 patients with C. arcuatus-positive skin test reactions and in 9 with negative results; all the patients had positive skin test reactions to D. pteronyssinus. RESULTS: The prevalence of positive skin test reactions to D. pteronyssinus was 94.2% and to C. arcuatus was 58%. There was a significant correlation between the number of mites to which patients were sensitized and the time of disease evolution (P = .02). Results of enzyme-linked immunosorbent assay inhibition experiments suggested minimal cross-reactivity between C. arcuatus and D. pteronyssinus. Immunoblot results confirmed specific IgE binding to several bands. Conjunctival test results were positive in 9 of 10 C. arcuatus-positive individuals and slightly positive in 2 of 9 C. arcuatus-negative, D. pteronyssinus-positive individuals. CONCLUSIONS: There is a high prevalence of sensitization to C. arcuatus in northern Spain. Sensitization to this species should be considered of clinical significance. There is minimal cross-reactivity between C. arcuatus and D. pteronyssinus.