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1.
Epidemiologic and in vitro data have shown that the association of house-dust mite (HDM) allergy and snail allergy in the same patients was due to cross-reactivity between HDM and snail allergenic components. However, the cross-reacting allergen(s) have not yet been identified. In vitro reactivity of seven patients' sera to the various extracts and hemolymph of four different Helix snail species was analyzed by IgE detection and immunodots and Western blots. Cross-reactivity between snails and Dermatophagoides pteronyssinus was assessed by immunodot and ELISA inhibition in two patients. Heterologous inhibition of the snail immunodot and ELISA was observed in one serum. Western blotting showed a specific binding on all four snail species extracts; molecular weights of snail allergens ranged from < 21 to 200 kDa. Marked individual differences were observed in the seven sera under study; most sera demonstrated IgE recognition of multiple bands, illustrating that no single allergen is responsible for cross-reactivity between snail and mite. These results confirm that cross-reactivity exists between snails of the Helix genus and HDM. This cross-reactivity, involving more than a single allergen, may be of clinical significance in atopic patients allergic to D. pteronyssinus. The identity of the cross-reacting allergens remains to be determined. Potential candidates include the thermostable minor allergens of D. pteronyssinus, tropomyosin and hemocyanin.  相似文献   

2.
Drug allergies are adverse reactions resulting from immunologic responses to drugs or their metabolites. These reactions result in predictable patterns of organ-specific or systemic hypersensitivity that usually recur on subsequent exposure to the same drug. Although diagnostic testing for drug allergy is available for only a few drugs, protocols have been developed to assist in management of allergic reactions to many drugs and biologic agents. Other protocols assist in the management of patients who develop drug reactions while undergoing multiple drug therapy or those with a history of adverse drug reactions who again require treatment for the same condition.  相似文献   

3.
OBJECTIVES: To determine the prevalence of drug allergies in a population of surgical patients. To establish a clinical classification of events as being very or not very likely to be allergic reactions. To detect which drug groups are associated with greater incidence of anaphylactic reaction and to analyze the severity of such reactions. PATIENTS AND METHODS: Epidemiological study. During a preoperative interview, patients were asked if they were aware of the existence of any episode of allergy to drugs. If a patient answered yes, a specific data collection questionnaire on allergies was completed. Based on signs and symptoms described by the patient, reactions were classified as indicating high likelihood of allergy, low likelihood of allergy, or as being of unknown origin. RESULTS: We questioned 1,218 patients (754 women/464 men), of whom 159 (13.05%) reported being allergic to drugs. The total number of drugs employed was 212 (1.34 drugs/patient). Antibiotics (54.7%), nonsteroidal anti-inflammatory drugs (NSAIDs) (19.3%), radiological contrast media (6.1%) and local anesthetics (4.7%) were the substance groups most often mentioned. We classified 74.5% of the reactions as indicating high likelihood of allergy, 19.8% as indicating low likelihood, and 5.6% to be of unknown origin. The skin was involved in 72.1% of the reactions that were highly likely to have been caused by allergy; 6.9% of these reactions involved the respiratory tract, 4.4% the circulatory system, 12% the skin plus respiratory tract, and 4.4% the skin plus respiratory and circulatory systems. The most severe reactions (16.4%) were associated with radiological contrast media (36.4%), NSAIDs (33.3%) and intravenous administration (38.1%). Signs of latex allergy were seen in 0.4% and signs of allergy to hair dyes in 0.9%. All allergy tests were negative in all these patients. CONCLUSIONS: Drug allergy is reported by 13% of patients. It is highly likely that 74.5% of reactions are due to allergy. Antibiotics are the most frequently implicated drugs, followed by NSAIDs. The most serious reactions are caused by radiological contrast media and NSAIDs. Intravenous administration causes the most serious reactions.  相似文献   

4.
Inhibitory mechanisms of isoproterenol and clenbuterol for immunoglobulin E (IgE)-mediated experimental allergic reactions in rats were studied. IgE-mediated passive cutaneous anaphylaxis, histamine-induced cutaneous reaction and serotonin-induced cutaneous reaction were evoked at the same time in the same rats. Isoproterenol administered intravenously immediately before challenge inhibited all these reactions significantly. Clenbuterol administered intravenously 0-3 h before challenge also significantly inhibited the three cutaneous reactions. The inhibition was maximum when the drug was given 1 h before challenge. Passive cutaneous anaphylaxis was always inhibited more potently than histamine-induced cutaneous reaction and serotonin-induced cutaneous reaction by these beta-adrenoceptor agonists. Passive peritoneal anaphylaxis was caused by injecting an antigen intravenously. Isoproterenol administered intravenously immediately before challenge inhibited the reaction significantly. Clenbuterol administered intravenously 0-3 h before challenge also significantly inhibited passive peritoneal anaphylaxis, maximally so when given 1 h before challenge. In vitro IgE-dependent histamine release from sensitized peritoneal mast cells or mesenteric mast cells was not affected by isoproterenol and clenbuterol. Mouse monoclonal IgE, a foreign protein, administered intravenously decreased rapidly in the circulation. About 50% of the mouse IgE given disappeared in 20 min. The decrease of mouse IgE was partly but significantly inhibited by the beta-adrenoceptor agonists, and the inhibition was abolished by simultaneous treatment with propranolol. These results indicate that direct inhibition of mast cell activation does not contribute to the potent inhibition of in vivo allergic reactions in rats by beta-adrenoceptor agonists, and that inhibition of the allergic cutaneous reaction is partially explained by the inhibition of vascular permeability increases caused by mast cell mediators. Penetration of intravenously administered antigen from blood vessels to peripheral tissues to cause mast cell activation might be inhibited by beta-adrenoceptor agonists, and this could play some role in inhibiting intravenous antigen-induced allergic reactions in rats. Clenbuterol exhibited its maximum action with some latency in vivo, suggesting that some time-requiring process may be involved in the manifestation of its action.  相似文献   

5.
A new immunoassay system utilizing new automatic instrumentation, new software for evaluation of data, and reagents updated for increased speed and accuracy was evaluated. Six clinical studies included 894 consecutive patients. Major symptoms were rhinoconjunctivitis, asthma, atopic dermatitis, and urticaria. The prevalence of inhalant allergy was 54-69%. Phadiatop, detecting atopic sensitization to common inhalant allergens, agreed with clinical diagnosis in 764/836 cases (91.4%). The clinical sensitivity and specificity were 93% and 89%, respectively. The clinical sensitivity and specificity of UniCAP specific IgE derived from 5170 comparisons with clinical diagnosis were 89% and 91%, respectively. Specific IgE measurements in UniCAP and in the Pharmacia CAP System agreed in 266/274 cases (97%). A comparison of the sensitivity and specificity of Pharmacia CAP System RAST in 1987 and with UniCAP specific IgE in 1995 showed equivalent performance without change of efficacy or degradation of IgE antibodies after 8 years. The systems were equivalent also in terms of measured values (r=0.96, slope=1.12), confirming the standardization of allergens and of assay calibration. UniCAP is an efficient laboratory system for routine diagnostic testing of allergy and a valuable tool for basic studies on allergens and antibodies.  相似文献   

6.
BACKGROUND: Immediate skin reactions to allergens are influenced by several factors, such as the amount of administered allergen, the level of specific IgE, releasability of mast cells and hyperresponsiveness of the target organ. METHODS: For the evaluation of factors influencing immediate skin response to intradermal allergen administration, we measured the wheal size 15 min after intradermal injection of 0.01-0.02 ml of the following agents: whole-body extract of Dermatophagoides farinae, 1,000 allergy units/ml; histamine, 0.1 mg/ml, and codeine sulfate, 0.09% in saline, and determined total IgE level, specific IgE and IgG subclass antibodies to D. farinae in 53 patients with respiratory allergy. RESULTS: Multiple regression analysis for factors influencing wheal size after intradermal injection of D. farinae, specific IgE antibody level to D. farinae and wheal size after intradermal administration of histamine showed statistically significant results (R2 = 0.42739, p = 0.0000; R2 = 0.50243, p = 0.0185, respectively). Multiple regression analysis for factors influencing wheal size after intradermal administration in the group with high levels of specific IgE to D. farinae (RAST class 3 or more) showed that wheal size after intradermal administration of codeine was the only factor exerting a statistically significant influence (p = 0.0119). CONCLUSION: Based on the above results, we can state that immediate responses to intradermal allergen administration were influenced by the level of specific IgE and hyperresponsiveness of the target organ to histamine, but that the immediate skin allergic responses in the presence of high levels of specific IgE were partially but significantly influenced by the releasability of skin mast cells.  相似文献   

7.
BACKGROUND: Allergenic crossreactivity of pollen and foods due to the antigeneic similarity of oligopeptides is a well established clinical phenomenon. OBJECTIVE: To determine the immunopathological relevance of antigen presentation, we analysed the HLA class-II genotype of patients with either pollen allergy or pollen associated food allergy. METHODS: One hundred and twenty patients with pollen allergy and 80 patients with pollen associated food allergy were evaluated by skin- prick tests, RAST, and HLA class-II genotyping. The control population comprised 4251 healthy blood and bone marrow donors. RESULTS: Monovalent pollen allergy was observed in 57% (n=68) of patients with pollinosis (57x grass pollen, 11x birch pollen), but only in 15% (n=12) of patients with food allergy (9x grass pollen, 3x birch pollen). Hazelnut (71%), almond (65%), walnut (44%) and apple (41%) were the most common food allergens and frequently associated with birch pollen allergy. Grass pollen allergy was associated with an increased frequency of HLA-DQB1*0301 (RR=2.3; EF=0.4; P=0.0016) when compared with the control population. HLA-DRB *08 conferred a sixfold higher risk for peanut allergy (EF=0.3; P=0.0013) and -DRB1*12 a 13-fold higher risk for carrot allergy (EF=0.3; P<0.000001). The differences on allele frequencies detected among patients with food allergies diminished or turned statistically insignificant when their genotypes were directly compared to those of patients with the corresponding pollen allergies. This was found in the case of birch pollen associated hazel nut allergy for the extended haplotype HLA-DRB1*01, -DQA1*0101, -DQB1*0501 as well as in grass pollen associated peanut allergy for HLA-DRB1*08 (from RR=6, P=0.0013 to insignificant) and in birch pollen associated carrot allergy for HLA-DRB1*12 (from RR=13, P < 0.000001 to insignificant). CONCLUSION: We were able to identify HLA class-II alleles associated with some allergies thus indicating that these alleles might confer susceptibility to the respective allergens. Similarities at the level of the HLA class-II genotype parallel the empirical finding of distinct cross-reactivity patterns thus complementing investigations of IgE specificities. Our observations provide evidence for the major importance of antigen presentation on the manifestation of distinct crossreactivity patterns.  相似文献   

8.
BACKGROUND: Anaphylaxis against Anacardiaceae nuts is uncommon and the allergens involved still poorly characterized. For this reason two patients with allergy towards pistachio nut (a member of the Anacardiaceae family) have been studied. OBJECTIVE: Identification of immunoallergens present in pistachio nut and analysis of crossreactive antigens in other members of the same plant family, specifically cashew and mango. METHODS: Presence of specific IgE for pistachio and cashew nut and for mango seed and pulp was determined by skin tests and radioallergosorbent assay (RAST). The allergenic profile of pistachio and cashew was analyzed by sodium dodecyl sulfatepolyacrylamide gel electrophoresis (SDS-PAGE) followed by immunoblotting. Crossreactivity between pistachio and the other Anacardiaceae was studied by RAST inhibition. RESULTS: Skin tests were positive for pistachio and cashew in the two children and for mango seed in one. RAST was positive for pistachio and cashew in both patients. On immunoblotting, serum from both patients recognized several pistachio and cashew allergens with a molecular weight ranging from < 14.2-70 kDa. RAST inhibition demonstrated common antigenic determinants between pistachio and cashew nut. Crossreactivity was also found between pistachio nut and mango seed but not with mango pulp. CONCLUSION: Pistachio nut contains several protein allergens able to trigger type I hypersensitivity reactions. These allergens can be found also in cashew nut and mango seed but not in mango pulp.  相似文献   

9.
Food allergies are immunologic reactions to food allergens or food components. Several distinct clinical entities fall under this term, including immediate-in-time allergic reactions, which are IgE-dependent and involve mast cells and basophils, and delayed-in-time reactions to foods, such as food-induced enterocolitis, which involve additional effector systems. Most food allergies are precipitated by a small number of foods. The diagnosis of these diseases depends on history, physical examination, specific diagnostic assays, and oral food challenge. The differential diagnosis of these diseases is extensive. Treatment of food allergies relies on identification of the food substance that induces the reaction and subsequent avoidance measures. When an individual inadvertently consumes food to which he or she is sensitized, pharmacologic treatment is available.  相似文献   

10.
During our first year of routine testing with Compositae allergens and extracts, contact allergy to Compositae was frequently found in eczema patients (4.5%), especially in middle-aged or elderly persons. Based on clinical patterns, patch test reactions and the long-term course of the disease, 4 groups of patients were recognized: (a) a small group with localized eczema; (b) another with classic Compositae dermatitis of exposed skin; (c) a 3rd group, the largest, with localized eczema that suddenly one summer turned into a widespread dermatitis; (d) a 4th group with a vesicular hand eczema and more-or-less widespread dermatitis with seasonal variation from the beginning. 65% of the patients had vesicular hand eczema at some time, partly reflecting the frequency of atopy (25%) and metal allergy (44%). 75% of the patients had contact allergy to > or = 1 compounds besides Compositae. Thus, Compositae allergy may be primary, e.g., in young patients with occupational plant contact, or secondary to other contact allergies, perhaps as a result of increased individual susceptibility. The clinical patterns in the latter patients were most often a widespread dermatitis with summer exacerbation. The variability in the clinical picture makes routine patch testing with Compositae allergens recommendable.  相似文献   

11.
The prevalence and severity of latex allergy has increased dramatically in the last 15 years due to exposure to natural rubber products. Although historically this health risk has been elevated in hospital personnel and patients, a recent survey has indicated a significant potential risk for the general population. To obtain a wide-spread source for latex exposure, we have considered tire debris. We have searched for the presence of latex allergens in passenger car and truck tire tread, in debris deposited from the atmosphere near a freeway, and in airborne particulate matter samples representative of the entire year 1993 at two sites in the Los Angeles basin (California). After extraction of the samples with phosphate buffered saline, a modified-ELISA inhibition assay was used to measure relative allergen potency and Western blot analyses were used to identify latex allergens. The inhibition studies with the human IgE latex assay revealed inhibition by the tire tread source samples and ambient freeway dust, as well as by control latex sap and latex glove extracts. Levels of extractable latex allergen per unit of protein extracted were about two orders of magnitude lower for tire tread as compared to latex gloves. Western blot analyses using binding of human IgE from latex-sensitive patients showed a band at 34-36 kDa in all tire and ambient samples. Long Beach and Los Angeles, California, air samples showed four additional bands between 50 and 135 kDa. Alternative Western blot analyses using rabbit IgG raised against latex proteins showed a broad band at 30-50 kDa in all samples, with additional bands in the urban air samples similar to the IgE results. A latex cross-reactive material was identified in mountain cedar. In conclusion, the latex allergens or latex cross-reactive material present in sedimented and airborne particulate material, derived from tire debris, and generated by heavy urban vehicle traffic could be important factors in producing latex allergy and asthma symptoms associated with air pollution particles.  相似文献   

12.
In this review, hyposensitization or immunotherapy will be discussed. The earliest immunotherapy was applicated in allergic respiratory diseases such as asthma and rhinitis. The most important indication has become the treatment of hymenoptera allergy. Some less frequently indications are associated with drug allergy. Immunotherapy is most frequently indicated in IgE mediated diseases, but new applications for cell mediated reactions will be described. With the introduction of molecular biology in allergology new theoretical possibilities emerged: use of peptide antigens, recombinant allergens, anticytokines.... Unfortunately, these newer approaches did not (yet) cause a breakthrough. The cost of these products will be a major draw back, even when ethical problems for using them on a larger scale will have been solved.  相似文献   

13.
Schistosomes are eliminated from laboratory rats around 28 days post-infection, whilst they are still resident within the hepatic portal distributaries of the liver. We have previously shown that their presence in this location is accompanied by an intense mastocytosis. We have investigated the potential relationships between IgE responses, the allergenicity of schistosome antigens, mast cell responsiveness, and worm elimination. Total and specific IgE were measured using an ELISA and a functional assay based on 3H serotonin release from activated rat basophilic leukemia cells (RBL-SRA), respectively. Both assays revealed that infected rats produced elevated IgE titres relative to naive animals. At days 28 and 35, mixed-sex infections stimulated a higher total IgE than male-only infections. IgE was affinity purified from rat infection serum and used to probe a fractionated soluble worm antigen preparation (SWAP) by Western blotting. Two allergenic products were detected of M(r) 67 and 36-38 kDa, the former having the same molecular weight as a previously identified secretory protein. IgE from mixed-sex schistosome infections bound strongly to the 36-38 kDa molecule, compared to the relatively weak binding exhibited by IgE from male-only infection serum. Since eggs were not recovered from the infected rats, this reactivity was attributed to the greater release of allergens from female worms. Results from the RBL-SRA showed that female SWAP was a more effective trigger of mast cell degranulation in vitro, for equal amounts of protein. This enhanced allergenicity was ascribed to the relative abundance of carbohydrate moieties. Our results support a role for IgE, and mast cell degranulation in the elimination of a primary schistosome burden from rats.  相似文献   

14.
Both health care workers and spina bifida patients are at risk to develop type I latex allergy since allergenic proteins of natural rubber latex are present in a variety of latex products. Natural latex contains more than 250 polypeptides and approximately 60 of them show IgE-binding characteristics. A multitude of these latex allergens has been identified, and their sensitization potency for both risk groups has been determined. While hevein (Hev b 6.02) is the major allergen in latex-allergic health care workers, 80% of latex sensitized-spina bifida children have IgE antibodies to the "rubber elongation factor" (Hev b 1). Almost all relevant latex allergens have been identified in natural latex products: however, no data on the allergen profiles of individual latex products exist. The knowledge of the major latex allergens enables improved diagnosis and to monitor the success of prevention strategies for decreasing the high prevalence of latex allergies.  相似文献   

15.
The atopic dermatitis is a multifactorial inheritable disease, in which pathogenesis in addition to environmental factors (climate, allergens, clothing) genetically determined multiplex metabolic differences (arachidonic acids, essential fatty acids) and immunologic alterations play an important role. Within immunologic findings the disturbances of balance in Th1 and Th2 subclasses, the increased degranulation activity of mast cells and the increased antigen presentation activity of Langerhans cells can be stressed. The clinical immunological alterations shown in the diseases, the increased production of IgE and so the type I. allergic reactions (urticaria, gastrointestinal manifestation of food allergy, allergic rhinitis, asthma bronchiale), the difference of cellular immunity of the skin can be explained by the above mentioned main immunological changes. In understanding of immunological origin of atopic dermatitis the IgE receptors expressed on the surface of Langerhans cells (connecting the immediate and delayed type of immune response) mean significant help.  相似文献   

16.
A method of utilizing morphological changes in rat mast cells to determine reaginic antibody activity in bovine serum is described. This technique, which has been shown to be useful for the diagnosis of allergies in man, relies on the ability of antigen to degranulate mast cells sensitized with allergic serum. Experiments with radioactively-labelled allergic bovine globulin indicated the specificity of the binding of such proteins to rat mast cells. Cross-reaction between reaginic bovine antibody and human IgE was shown by a binding assay involving the uptake of 125I-labelled anti-human IgE globulin by mast cells incubated with bovine passive cutaneous anaphylaxis positive globulin.  相似文献   

17.
True food allergies are much less prevalent than is generally believed. They are more common in infants and children under age three than in older children and adults. Infant colic generally is not caused by a food allergy. In infants, urticaria, eczema or gastrointestinal bleeding may be due to foods such as milk and eggs, but clinical tolerance usually develops within a few years. Peanuts, tree nuts, seafood and seeds, as well as milk and eggs, can cause anaphylaxis in highly allergic children, and reexposure to such foods presents the risk of life-threatening reactions. Immediate-reacting allergy skin tests and in vitro IgE antibody tests can be used to screen for food allergy. Only food challenge, however, can confirm a reaction to a particular food. Management of food allergy, once the initial symptoms are confirmed, consists of avoidance of specific foods, sometimes for a lifetime. All children at risk for food anaphylaxis should be identified, and their parents or caretakers should be prepared to administer epinephrine before taking the child to the emergency room.  相似文献   

18.
In the group of 50 patients suffering from grass pollen allergy and successfully treated with SIT for three consecutive years, we observed in 5 persons after the end of this treatment the induction of allergy to new allergens (to weeds, mites or tree) manifested by the change of the symptoms season. The induction of the new kind of allergy was confirmed by revealing of the positive skin prick tests to new allergens and by an increase of the specific IgE serum level to them. Despite disappearance of the symptoms of the illness during grass pollen season in all 5 patients we noted the higher total IgE as well as specific to grasses IgE serum level, in comparison to the value at the start of SIT. In the paper the possible mechanisms of this phenomenon are discussed, which seems to be not connected with the natural development of allergy and which confirms once more that during SIT individual changes in humoral and cellular immunity of the patient take place, sometimes very difficult to be predicted. They may among others switch clinical profile of allergy, what indicates that patient during SIT should be under the careful immunological supervision.  相似文献   

19.
We report the case of a 48-year-old patient suffered from asthma and conjunctivitis caused by an immediate type allergy to weeping fig (Ficus benjamina). By RAST inhibition test we could demonstrate that IgE antibodies react with allergens of fig; however our patient tolerated figs in oral provocation test. Sensitization to latex proteins reported to be cross reactive to Ficus species was not found. Ficus benjamina allergens represent relevant indoor allergens. A standardized allergen extract for skin testing is not yet available. Allergen specific IgE is mostly found in patients with strongly positive prick test results using the native sap of the tree. In 12 of 64 latex allergic patients we found simultaneous sensitization to weeping fig, so that cros-sensitization has to been considered in patients with IgE-mediated sensitization to latex.  相似文献   

20.
BACKGROUND: A family history of atopy is a poor predictor of sensitization to inhalant allergens and allergic disease during childhood. We recently identified early sensitization to food allergens, especially hen's egg, as a valuable predictor of subsequent sensitization to inhalant allergens. OBJECTIVE: (1) Whether prediction will be improved by in vitro allergy tests at 1 year of age in combination with family history and medical history data. (2) Comparison with the capacities of in vitro tests to predict sensitization to aeroallergens. METHODS: Of an observational birth cohort study (MAS) 49 children who were sensitized to inhalant allergens at 5 years of age and 116 non-sensitized controls were included in the present study. For the prediction of sensitization to inhalant allergens the following prognostic factors were evaluated: atopic family history (FH), atopic dermatitis (AD) during the first year of life, two in vitro allergy tests for specific IgE to common food allergens at 1 year of age (fx5 [Pharmacia] and single allergen specific tests (sIgE) for four allergens) and 'high' total serum IgE, defined by three different cut off points. RESULTS: The combination of medical history data and laboratory tests resulted in the best predictive discrimination. The positive predictive values (PPV) were higher if sensitization to food was detected by single allergen specific tests (PPV: 66%/75%/100% corresponding to the three evaluated risk groups) than by the qualitative fx5 (PPV: 46%/65%/100%). The negative predictive values were equal for both tests (69 and 92% for the two low risk groups). High total serum IgE had low predictive capacity. CONCLUSION: During infancy the prediction of sensitization to inhalant allergens should be based on medical history data and allergy tests determining sensitization to food allergens. The in vitro tests improve the predictive discrimination, but the individual risk profile of the child must be considered for a reliable and valid prediction.  相似文献   

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