Prick Test Results Research Articles

Immunophenotyping of the cutaneous cellular infiltrate after atopy patch testing in cats with atopic dermatitis.

Cats with spontaneously occurring atopic dermatitis have clinical and immunocytochemical characteristics compatible with these in humans with atopic dermatitis (AD). The atopy patch test (APT) has proven to be a valuable tool in elucidating the disease process in humans. Additionally, the APT is very specific and bypasses the problem of conflicting results due to differences in chronicity of lesions of AD patients. We adapted the APT for use in cats to explore the suitability of the APT as a tool to study the onset of allergic inflammation in cats with atopic dermatitis. APT were performed in AD cats (n = 6) and healthy cats (n = 10). All cats were patch tested with two allergens in three different dilutions and a diluent control. The allergens for the APT were selected from positive intradermal test and /or prick test results and consisted of: Dermatophagoides farinae, D. pteronyssinus, Tyrophagus putrescentiae, and a grass pollen mixture. APT were read after 10, 24 and 48 h, and punch biopsies for immunohistochemical evaluation were collected at these time points. Macroscopically positive APT reactions were observed in three out of six cats at 24 and/or 48 h with allergen concentrations of 25,000 and 100,000 NU/ml. Reactions were not observed at negative control sites and neither in control animals. A significantly increased number of IL-4+, CD4+, CD3+, MHC class II+ and CD1a+ cells was found in one AD cat with positive APT reactions. Five out of six AD cats had significantly increased IL-4+ T cell numbers at 24 and/or 48 h. Our data indicate that in cats, macroscopically positive patch test reactions can be induced, which have a cellular infiltrate similar to that in lesional skin. We found a high specificity and a macroscopically positive APT reaction in half of the cats, which is similar to what is seen in humans. Hence, the APT in cats might be a useful tool in studying the immunopathogenesis of feline atopic dermatitis.

Allergic rhinitis in children with attention-deficit/hyperactivity disorder

Both allergic rhinitis and attention-deficit/hyperactivity disorder (ADHD) are common pediatric conditions associated with learning difficulties and sleep disturbances. There are conflicting research data regarding the association between ADHD and atopic disorders. To determine the prevalence of allergic rhinitis in patients with physician-diagnosed ADHD. Patients 5 to 18 years of age who presented with a Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition diagnosis of ADHD to an outpatient pediatric psychiatry clinic were screened for allergic rhinitis with focused history, physical examination, and skin prick testing to common aeroallergens. Thirty patients were interviewed, with 23 of these undergoing physical examination and skin prick testing. Eighty percent reported allergic rhinitis symptoms, whereas 61% had at least 1 positive prick skin test result. Forty-three percent showed typical physical signs of allergic rhinitis, 100% had a positive atopic family history, and 53% had other associated atopic disorders. Most children with ADHD displayed symptoms and skin prick test results consistent with allergic rhinitis. Nasal obstruction and other symptoms of allergic rhinitis could explain some of the cognitive patterns observed in ADHD, which might result from sleep disturbance known to occur with allergic rhinitis. Therefore, evaluation and treatment of allergic rhinitis could benefit patients with ADHD.

Anaphylaxis to wheat beer

Despite its worldwide and abundant consumption, beer has rarely been found to cause anaphylaxis. Barley malt contained in lager beers seems to be an important elicitor. To report the unusual case of severe anaphylaxis following the ingestion of wheat beer. A 59-year-old man experienced angioedema, generalized urticaria, and unconsciousness after ingestion of wheat beer. He tolerated lager beer well. For diagnostic evaluation, skin prick tests, oral challenge tests, and identification of specific IgE antibodies were performed. Skin prick test results with standard series of common aeroallergens and food allergens were negative with the exception of a 1 + reaction to wheat flour. The results of skin prick tests with native materials were positive for 2 brands of wheat beer and wheat malt shred but negative for baker's yeast, hops, and a brand of lager beer. Oral challenges with wheat beer or wheat flour elicited urticaria. By CAP-FEIA, specific IgE antibodies to wheat and barley flour but not to hops or baker's yeast were found in serum. Immunoblot analysis revealed that patient's IgE was bound to a protein of approximately 35 kDa in wheat extract. This is the first report, to our knowledge, on anaphylaxis to beer attributable to wheat allergy.

The relationship between early fever and allergic sensitization at age 6 to 7 years

Background The hygiene hypothesis suggests that early infections might protect against later allergic sensitization. Objective The purpose of this study was to determine whether fevers before age 1 year were associated with allergic sensitization at age 6 to 7 years. Methods Eight hundred thirty-five children from suburban Detroit, Michigan, were enrolled at birth. Clinic records from their first year were abstracted for episodes of fever, antibiotic use, and respiratory infections. Fever was defined as a rectal temperature of 38.3°C (101°F) or greater or its equivalent measured at another site. At age 6 to 7 years, 441 children underwent allergy testing. The primary outcome measures were atopy (≥1 positive skin prick test result), seroatopy (≥1 positive allergen-specific IgE level), and allergic sensitization (either seroatopy or atopy). Results By age 1 year, 207 (46.9%) of the 441 participants had a documented fever. Among children with 0, 1, or 2 or more fevers in the first year, 33.3%, 31.3%, and 26.0% demonstrated atopy at age 6 to 7 years, respectively ( P = .504); 43.4%, 39.7%, and 25.0% had seroatopy, respectively ( P = .032); and 50.0%, 46.7%, and 31.3% had allergic sensitization, respectively ( P = .028). After adjusting for potential confounders, each febrile episode in the first year was associated with reduced odds for allergic sensitization (adjusted odds ratio, 0.69; 95% CI, 0.47-1.00). Febrile upper respiratory tract infections, in particular, were associated with lower odds of allergic sensitization (adjusted odds ratio, 0.55; 95% CI, 0.31-0.97) per episode. Conclusion This study provides direct support for the hygiene hypothesis because children with fevers before age 1 year were less likely to demonstrate allergic sensitivity at age 6 to 7 years.

The effect of delayed introduction of solids on rates of eczema and infant sensitization to food and aeroallergens at 1 and 3 years of age

Rationale The delayed introduction of solids, particularly of allergenic foods, into an infants diet is advocated by the American Academy of Pediatrics as an allergy prevention measure. Such advice is also incorporated into many allergy prevention studies. Methods We compared retrospectively sensitization rates of control groups of two intervention allergy prevention studies. Recruitment to the studies ran consecutively, with the same criteria and procedures being applied to each. Mothers from the first intervention study (S1) received no weaning advice, whereas mothers from the later study (S2) were advised to delay the introduction of solids until 4 months of age and not to introduce allergenic foods until after 6 months of age. Skin prick test results and presence of eczema were compared at 1 year (n=185) and 3 years of age (n=79). Results At one year, sensitization rates in S2 mothers was 21% to food allergens and 36% to food and aeroallergens combined. In S1 mothers these values were 8% and 20% respectively. These differences are significant (p=0.023 and p=0.015). At three years of age there was no difference in sensitization rates (p=1.0 and p=0.79). There was no significant difference in eczema rates at either time point (p=0.3 and p=0.3). Conclusions Delayed weaning strategies may not be as an effective allergy prevention measure as is currently thought and should be further investigated.

Cork workers' occupational asthma: lack of association with allergic sensitisation to fungi of the work environment.

To evaluate allergic sensitisation to Chrysonilia sitophila, Penicillium glabrum, and Trichoderma longibrachiatum in cork workers with asthma. Skin prick tests with a battery of common allergens and with the three fungi were performed on ten cork workers with asthma and eight non-exposed asthmatics. Based on serial peak expiratory flow measurements, five were classified as having occupational asthma (AO) and five as having non-occupational asthma (NOA). In exposed patients, specific antibodies for the three fungi were also studied by immunoblotting Two out of ten patients with occupational exposure and four out of eight of the control group showed positive results for skin prick tests for common allergens. Moreover, two out of five patients with OA and three out of eight controls exhibited sensitisation to storage mites. All exposed patients (with OA or NOA) had negative skin prick test results for the fungal extracts. In patients with asthma and occupational exposure, immunoblotting results confirmed the absence of specific IgE. However, specific IgG4 was present in some cases. Atopy does not seem to characterise occupational asthma in cork workers. Despite their long exposure to moulds, we could not find evidence of IgE sensitisation to the three most prevalent cork fungi in patients with OA, which points to the search for other causative agents, such as cork chemical compounds or contaminants.

Contact Allergic Reactions of the Vulva: A 14-Year Review

In women with vulval complaints, irritant contact dermatitis is more common than allergic contact dermatitis, but secondary sensitization has to be taken into consideration since these patients often use several topical medications. The aims of this retrospective study were to establish the prevalence of allergic contact dermatitis in patients with vulval complaints and to verify how many patients with allergic contact dermatitis suffered from a previous pathology. We reviewed patch- and prick-test results from 92 women. The women had all been administered the European Standard series, and most had also been tested for other allergens such as the ingredients of topical pharmaceutical products and cosmetics. Thirty-five patients (38%) presented with one or more positive allergic reactions. For 15 of the patients, these reactions were considered to be relevant to their clinical condition and were most often due to contact dermatitis from topical pharmaceutical products. Three patients presented with positive and relevant contact urticaria syndrome from latex, and two patients presented with protein contact dermatitis from human seminal plasma. Patients with vulval dermatitis are at risk of developing contact sensitivities, particularly to topical pharmaceutical products; therefore, attention should be paid to this problem when such products are prescribed.

Occupational Asthma Due to Grain Pests Eurygaster and Ephestia

Background: Workers occupationally exposed to grain dust have a high prevalence of asthma. The pathogenesis of their respiratory symptoms remains obscure when sensitization to cereal allergens has not been proved. Given the ubiquity of arthropods in stored vegetable products, we have studied the allergenic potential of two very prevalent grain pests, Eurygaster and Ephestia, as a cause of occupational asthma. We have also studied the allergenic relationship between Anisakis simplex (AS)and these pests. Methods: We selected 15 asthmatic workers exposed to cereal dust, in whom sensitization to cereal allergens was not clear. As controls, we selected a patient who suffered from anaphylaxis after the ingestion of cereals, 6 patients sensitized to different arthropods, 1 patient who suffered from asthma after inhaling fish flour contaminated with AS, and a pool of 40 asthmatic patients with different ethiologies not due to arthropods or cereals. We performed prick tests with these pests, AS, and pure and parasitized flours, bronchial challenges, specific IgE determination, and RAST inhibition. Results: All of the 15 cereal‐exposed workers were sensitized to Eurygaster and Ephestia. Only 2 had detectable levels of serum IgE to these pests, but 13 presented a positive prick test result and IgE to AS without problems after eating fish. Bronchial challenges were positive to Eurygaster in 7 patients and to Ephestia in 2 patients. Twelve patients had positive prick tests to parasitized flour but not to pure flour. The patient with cereal anaplylaxis presented sensitization to both flours but not to AS. In the control group, the patient who suffered from asthma after the inhalation of AS‐parasitized fish flour presented a positive prick test result and high levels of specific IgE to these pests. The RAST inhibition showed cross‐reactivity between Eurygaster and AS in this patient, but the inhibition was not as evident with the sera of other workers. The same tests in the group of 40 asthmatic patients were negative. Conclusions: The clinical importance of pests as a cause of baker's asthma should not be underestimated. Sensitization to Eurygaster and Ephestia could be important in the asthma episodes suffered by our patients, and the parasitized wheat was found to have a higher allergenic potential than pure cereal flour.

Recombinant birch allergens (Bet v 1 and Bet v 2) and the oral allergy syndrome in patients allergic to birch pollen

IgE cross-reactivity between pollen and food allergens represents the molecular basis for oral allergy syndrome (OAS). To evaluate specific IgE for Bet v 1 and Bet v 2 in the serum of patients sensitized to birch pollen and to identify whether IgE antibodies to Bet v 1 and Bet v 2 were predictors of OAS. Thirty-three patients with skin prick test results and radioallergosorbent assay test results positive to birch pollen, 12 (36%) of whom had OAS symptoms, were enrolled in the study. Serum levels of specific IgE were determined by the fluoroenzyme immunoassay technique. The t test revealed significantly higher serum IgE levels against Bet v 1, Bet v 2, and birch pollen in the 12 symptomatic patients with respect to those without OAS (32.4 vs 12.4 kU/L, 7.6 vs 1.3 kU/L, and 42.3 vs 17.3 kU/L, respectively). Attempts to establish a threshold value of serum IgE antibirch pollen and the appearance of OAS revealed that a level of 20 kU/L or more yields an efficiency of the test equal to 70%. In our study, quantitative birch specific IgE level proved useful in predicting clinical allergy symptoms with birch exposure.

Evaluation of adverse reactions to local anesthetics: experience with 236 patients

Adverse reactions to local anesthetics (LAs) are frequently reported. Although most of these reactions are not immune mediated, many patients are referred to allergy clinics and undergo extensive evaluation. To determine the prevalence of true LA allergy among the patients referred for suspected hypersensitivity and to evaluate the usefulness of the currently used evaluation protocol. A total of 236 patients referred to our allergy clinic for investigation of LA hypersensitivity were included in this study. The evaluation protocol was composed of skin prick and intradermal tests, followed by subcutaneous challenge with unrelated LA preparations that contained preservatives. Skin prick and intradermal test results were negative for all subjects. No objective adverse reactions were observed during the challenge in all but 1 patient, who developed local erythema at the site of injection and later underwent an uneventful challenge with a different LA. Allergic reactions were not reproduced during testing and challenge with LA preparations that contained preservatives or preservatives with adrenaline in our large group of patients with suspected LA allergy. Since both prick and intradermal skin test results were negative in all the patients and did not provide us with useful information, we propose to modify the standard protocol by omitting intradermal tests and shortening the challenge. We also suggest that the whole procedure be performed with LAs that contain preservatives, which are usually the preferred preparations widely used in daily practice.

Occupational asthma due to exposure to iroko wood dust

Occupational asthma (OA) from iroko wood has been reported primarily in case reports. To improve understanding of the pathogenesis of OA induced by iroko wood dust. Three groups of woodworkers were included in this study: 9 workers who had clinically proven OA from iroko; 10 asymptomatic woodworkers; and 10 woodworkers with asthma. All patients underwent the following tests: a skin test with an iroko aqueous extract, specific IgE determination, and an iroko bronchial provocation test (IBPT). An eosinophil count was determined before and after the IBPT, and a methacholine inhalation test was performed after avoidance of exposure to iroko. Patients were asked to monitor their peak expiratory flow rates during a week at work followed by a week's vacation. In all patients with a personal history predictive of OA from iroko, a reduction of the peak expiratory flow rate and positivity to the IBPT while working with iroko were present. The latter test result showed a dual response, with a decrease in forced expiratory volume in 1 second from 25% to 32% at 10 minutes and a further decrease from 35% to 43% at 8 hours; at 24 hours, the eosinophil count was higher (P = .046). In 4 patients, the intradermal test results with iroko extract were positive, whereas the skin prick test result and the specific IgE determination were negative in all patients. The methacholine test result was also positive. In the control groups, all the test results with iroko extract were negative. Our data suggest that OA due to iroko wood may be induced by immunologic mechanisms other than IgE-mediated immediate hypersensitivity reactions.

Valeur diagnostique du dosage des IgE spécifiques dirigées contre le blanc et le jaune d’œuf dans le diagnostic de l’allergie alimentaire à l’œuf de poule chez l’enfant

The aim of this study was to define levels of egg white- and yolk-specific IgE antibodies that would confirm the diagnosis of egg allergy with a positive predictive value (PPV) of 100%. The study was carried out on 185 children with suspected food allergy recruited consecutively at the Children’s Hospital. One group included 100 children with a positive hen’s egg oral food challenge (OFC) test. They were compared with 85 children with peanut allergy but not egg allergy (negative egg OFC). We analyzed the children’s clinical symptoms, family history of atopic diseases, skin prick test results (SPT) with raw egg white and yolk, serum samples for specific IgE antibodies to egg white and yolk using the Pharmacia Cap system FEIA method, open controlled challenge tests with whole raw egg or double-blind controlled food challenges with peanut. Median age was 2.1 years (range 0.8–15 years). The median skin reaction to the egg extract was 11.3 mm (range 0–25 mm) in the first group and 5.5 mm in the second ( P = 0.00001). We found a higher level of egg white-specific IgE antibodies in the egg allergy group (22.5 vs. 0.76 kUA/l, P = 0.000001) and also a higher level of yolk-specific IgE antibodies (6 vs. 0.35 kUA/l, P = 0.0001). For the egg white antibodies, a threshold value equal to or greater than 7.5 kUA/l resulted in a PPV of 100% and a negative predictive value (NPV) of 68%. For the yolk-specific antibodies, a threshold value equal to or greater than 5.5 kUA/l resulted in a PPV of 100% and a NPV of 52%. Conclusion. – Our study demonstrated better sensitivity for egg white-specific IgE antibodies and better specificity for egg yolk-specific IgE antibodies. Both measurements are useful for the diagnosis of egg allergy in children. In addition, with an egg white-specific IgE antibody level equal to or greater than 7.5 kUA/l and a yolk-specific IgE antibody level equal to or greater than 5.5 kUA/l, the patient can be said to be egg-allergic with nearly 100% certainty.

Do asthma patients in general practice profit from a structured allergy evaluation and skin testing? A pilot study

Background: Although allergy is central to the pathophysiology of asthma, little is known about the benefits of a structured approach to allergen diagnosis and management in primary care asthma patients. Objectives: We studied effects of a structured allergen evaluation and allergen avoidance advice combined with or without additional allergy skin testing on health status, illness perception, and lung function of asthma patients treated in general practice. Method: Fifty-four asthma patients were randomly assigned to three groups: (i) Standard asthma care with information on the stepwise treatment approach, a written action plan, and inhaler technique training; (ii) Additional structured allergen evaluation and avoidance advice; (iii) Additional structured allergen evaluation and avoidance advice based on skin prick test results. Patients were seen for one initial appointment at a primary care asthma clinic and a follow-up examination 3 months later. On both occasions, questionnaire measures of symptoms, illness perception, and the perceived control of asthma were administered. Lung function was measured by spirometry (PEF, FEV 1). Perceived allergic asthma triggers, the trigger impact, and the trigger control were assessed in both intervention groups. Results: Following intervention, a decrease in beta-adrenergic inhaler use, an increase in the perceived control of asthma, and a decrease in the bothering from asthma symptoms were observed for all three groups. Intervention groups showed a higher awareness of animal-allergic triggers, and the perceived control of asthma triggers was increased in the group receiving no skin tests. FEV 1 showed an improvement in both intervention groups. Conclusion: Structured allergy evaluation and avoidance advice can improve lung function and the control of asthma in primary care. Further research is needed on the additional benefits of allergy skin testing.

Skin Tests and Conjunctival and Bronchial Challenges with Extracts of Blomia tropicalis and Dermatophagoides pteronyssinus in Patients with Allergic Asthma and/or Rhinoconjunctivitis

Background:Blomia tropicalis and Dermatophagoides pteronyssinus are important mite species in Tenerife, Canary Islands, Spain. Several studies have demonstrated a variable degree of allergenic cross-reactivity in vitro. However, only a few have addressed their allergenic cross-reactivity using challenge tests. Objective: The objective of this study was to conduct conjunctival and bronchial challenge tests with B. tropicalis and D. pteronyssinus extracts in a group of 42 patients with allergic asthma and/or rhinoconjunctivitis sensitised to house dust mites (31 females, 11 males; mean age 21.7 ± 7.02 years). Methods: Prick tests using standardised extracts and specific IgE determinations using the CAP system were performed. Bronchial and/or conjunctival challenges were conducted using freeze-dried extracts of both mite species. A patient was considered sensitive to a mite species if she/he had a positive prick and/or CAP test result. A total of 32 conjunctival and 15 bronchial challenges were performed with both mite species. Results: Prick tests were positive to B. tropicalis in 23 patients (54.7%) and to D. pteronyssinus in 41 (97.6%). One patient (2.4%) was exclusively sensitive to B. tropicalis. The CAP test was positive for B. tropicalis in 28 patients and for D. pteronyssinus in 41. Conjunctival challenges to B. tropicalis were positive in 20 patients (18 sensitised and 2 non-sensitised) and negative in 12 (5 sensitised and 7 non-sensitised patients). Conjunctival challenges with D. pteronyssinus were positive in all 31 D. pteronyssinus-sensitised patients who underwent conjunctival challenges. Bronchial challenges with B. tropicalis were positive in 9 sensitised patients and negative in 6 patients (2 sensitised and 4 non-sensitised). Bronchial challenges with D. pteronyssinus were positive in all patients except 1, who only reacted to B. tropicalis. Conclusions: Allergens of the mite species B. tropicalis induce positive conjunctival and bronchial challenges in B. tropicalis-sensitised individuals. Our results suggest that although there is a low to moderate degree of in vivo cross-reactivity between B. tropicalis and D. pteronyssinus, B. tropicalis seems to be a relevant source of allergens in areas where patients are exposed.

Characterization of allergenic food proteins for improved diagnostic methods.

Diagnostic decision points for food allergen-specific serum IgE concentration and for skin prick test results have been established for several foods, reducing the requirement for food challenges in a number of patients. Many patients, however, still need to undergo oral food challenges because their food-specific IgE level is in the undefined range. In addition, diagnostic decision points could not be established for several foods. It appears that measurement of serum specific IgE concentrations to individual allergens is superior to determination of specific IgE to the crude food extract containing allergenic and nonallergenic proteins. This review will outline recent advantages in characterization of food allergens as well as the relevance of this knowledge for use in recently developed protein microarray technology. Protein microarrays have been developed to profile allergen-specific IgE antibodies from human serum with the advantage of screening hundreds of allergens in parallel using minute amounts of blood. This technology, however, requires prior knowledge of the proteins to be studied. The identification and characterization of clinically relevant allergens have increased dramatically within the last several years. Relevant new allergens have been identified, especially in tree nuts and seeds. Interestingly, most of these allergens belong to the same family of seed storage proteins. In addition, known food allergens have been further characterized and IgE-binding sites have been determined. Moreover, 'informative' peptides shown to be predictive for the persistence of food allergy have been identified. The combination of food allergen characterization and protein or peptide microarray technology will enable us to develop improved diagnostic tools in food allergy.

Allergy to heparin: A new in vitro diagnostic technique

IntroductionFew descriptions of allergic reactions to heparin have been published, because these reactions are not well known, their prevalence is low and they are difficult to diagnose due to the lack of an in vitro test until now. We propose a new technique, the basophil activation test (BAT) for the diagnosis of these reactions Methods and resultsWe performed in vivo and in vitro studies with heparin and its derivatives in two patients with heparin-induced acute urticaria. In both patients the results of prick tests with sodium and calcium heparin, enoxaparin and nadroparin with immediate reading were negative. Intradermal skin tests with immediate reading and reading at 48 and at 96 hours with calcium heparin, enoxaparin and nadroparin were positive in the immediate reading and after 48 hours in the first patient. The second patient showed positivity to nadroparin in the immediate reading. The same drugs were also tested using patch tests, with reading after 48 and 72 hours. The second patient showed positivity to nadroparin after 48 hoursThe BAT was positive to enoxaparin in the first patient and revealed showed slight positivity to sodium heparin in the second patient ConclusionsWe consider the BAT to be a useful, safe and reliable test for the in vitro diagnosis of heparin allergy. This test avoids the use of provocation tests, which present a risk to the patient

Retrospective evaluation of epidermal skin prick tests in patients living in Aegean region

Sensitization to aeroallergens of Aegean region is not well decumented. In this study we evaluated the epidermal skin prick test results of the patients who applied to allergy outpatient department retrospectivelyEpidermal skin prick test of the 5055 patients were evaluated. Of these patients 2638 (52 %) were female, 2417 (48 %) male, 1213 (24 %) adult and 3842 (76 %) pediatric patient, 1163 (23 %) patients were allergic rhinitis, 2477 (49 %) were bronchial asthma, 505 (10 %) were allergic rhinitis with bronchial asthma, 556 (11 %) were chronic urticaria, 253 (5 %) were wheezy infant and 101 (2 %) patients were atopic dermatitis, 2932 (58 %) had atopy history in their first and second degree relatives. Patients were aged between 3.5 months and 79 years (mean 14.1 ± 3.2 years and median 11 years). In epidermal skin prick tests sensitization to house dust mites (D. farinae, D. pteroniyssinus), pollens (grass, cereals and trees), moulds, animal danders, foods (especially in early childhood) and cockroach were evaluatedOur data indicate that allergens that may be the cause of the high prevalence of allergic diseases in I?zmir are probably produced by pollens and mites

Allergie alimentaire au raisin. Une nouvelle observation chez un enfant de 4 ans

Allergy to grape is rare. Only three cases in children and about 20 in adults have been reported. The presenting complaints are most often those of an oral allergy syndrome, although more severe manifestations, including asthma, exercise-induced anaphylaxis and anaphylactic shock, have been reported. We report a case of allergy to grape in a four-year old boy in which the clinical manifestation was limited to an oral allergy syndrome. The diagnosis was confirmed by a positive labial test to a fresh grape in addition to a positive prick test and positive specific IgE positive results The patient was also allergic to house dust mites, grass pollen, egg, fish, coconut, kiwi, almond and latex. Molecular relations responsible for cross-reacting allergies are discussed.

Inhibitory effects of oral prednisolone and fexofenadine on skin responses by prick tests with histamine and compound 48/80

The prick test is a useful skin test for diagnosing immediate hypersensitivity response. Sometimes it is necessary to perform prick tests on patients who have already received antihistamines or corticosteroids. It is, however, occasionally uncertain whether the results of prick tests are reliable. In this study, the inhibitory effects of prednisolone (10 mg/day) and fexofenadine (120 mg/day) on the response to prick tests induced with histamine and compound 48/80 were examined. During a 7-day-continual drug administration, prick tests were performed 8 h after drug administration. The inhibitory effects of fexofenadine on both the histamine- and compound 48/80-induced skin responses were exhibited on the 1st day and persisted from 24 to 36 h after the final administration. The histamine-induced wheal responses were not inhibited by prednisolone, while the compound 48/80-induced flare and wheal responses were significantly inhibited on the 5th day of drug administration. These responses returned to the baseline level 24 h after the last drug administration. Thus, the results of skin tests performed during administration of antihistamines and corticosteroids should be carefully interpreted.

Association between Mite Allergen (Der p 1, Der f 1, Blo t 5) Levels and Microscopic Identification of Mites or Skin Prick Test Results in Asthmatic Subjects

Background: Mite allergens have been involved in airway sensitization and allergic diseases. Immunoassays for the identification and quantifiction of house dust mite (HDM) allergens are useful to improve the knowledge of regional mite fauna and the remediation of mite allergens in allergic diseases. The present study analyzed the association between levels of HDM allergen and results of mite identification or skin prick test (SPT) in two different areas of Bahia, Brazil. Methods: Forty-two asthmatic subjects from a rural area (group I; n = 21) and a slum (group II; n = 21) were evaluated through SPT with HDM allergens and had dust samples collected at their homes for mite identification and allergen measurements. Results: Positive SPT to Dermatophagoides pteronyssinus, Dermatophagoides farinae and Blomia tropicalis allergens were observed in 42.9, 38.0 and 42.9% subjects from group I and in 47.6, 19.0 and 33.3% subjects from group II, respectively. D. pteronyssinus and B. tropicalis were identified in approximately 76 and 50% of samples from both groups, respectively. D. farinae was identified in 38.0 and 9.5% of samples from groups I and II, respectively (p < 0.005). Der p 1, Der f 1 and Blo t 5 detection were associated with mite identification (p < 0.05). Association between HDM allergen levels over 2 µg/g of dust and positive SPT occurred only with D. pteronyssinus (p < 0.0001). Conclusions:D. pteronyssinus was the most prevalent mite species in this study followed by B. tropicalis and D. farinae. Immunoassays done to measure mite allergens were associated with mite-species identification. We conclude that these three mite species must be included on panels for the diagnosis of allergic airway diseases in subjects living in such regions.