Determination Of Specific IgE Antibodies Research Articles

B-060 Prevalence of CCD and profilins antibodies in a seasonal allergy study

Abstract Background Allergen sources are complex and heterogeneous mixtures of proteins, which may contain from innocuous IgE-binding structures such as CCDs (cross-reactive carbohydrate determinants), which are not associated with symptoms, to a panallergen such as profilin, which is associated with multiple sensitizations to pollen and pollen-food-latex syndromes. CCDs are present in many plant and animal allergens and cause strong cross-reactivity due to the high similarity of their structure. They complicate the interpretation of positive in vitro diagnostic results because they do not associate symptomatology and, thats why, the determination of specific IgE antibodies against CCDs can provide useful information when positive IgE results are not consistent with the clinical picture. Profilins are ubiquitous proteins present in all eukaryotic cells and identified as allergens in pollen, latex and plant foods. The highly conserved structure explains the cross-reactivity of IgE antibodies against plant profilins and their designation as panallergens. As a panallergen, profilin is associated with multiple pollen sensitization and pollen-food-latex syndromes that the allergist must be aware of for accurate diagnosis and successful treatment of allergic diseases. We intend to evaluate the prevalence of these two markers with a new diagnostic tool, since profilins and CCDs are the substances most likely to cause in vitro cross-reactivity. Methods In our study 8,242 adults who presented rhinoconjunctivitis and visited their primary care center were included. The samples were analyzed in serum samples which were routinely processed in our laboratory with the EUROLINE Mediterranean Inhalation 2 (IgE) assay from Euroimmun® from February to July 2023, according to the manufacturer’s protocols. Patients with specific IgE levels ≥ 0.35 kU/L were identified as sensitized to allergen. Results A total of 8,242 patients were enrolled in this study, 5,173 women and 3,069 men, ranging in age from 15 to 65 years. Of these, 279 patients (3.39%) had antibodies against CCD, 570 (6.92%) antibodies against profilins and 183 (2.22%) had both. A higher prevalence of these antibodies was observed in men (CCD, n = 168, 5.47%; Profilins, n = 308, 10.04%) than in women (CCD, n = 111, 2.15%; Profilins, n = 262, 5.06%). Both markers were more frequently found in the presence of specific IgE antibodies to grass and weed pollens. Conclusions The possibility of detecting the presence of IgE antibodies against CCD and panallergenic profilins is useful to detect cross-reactivity in vitro, which could explain the differences found between laboratory results and patients' symptoms, helping the allergist to make a diagnosis with greater certainty and accuracy.

Concordance study between two analytical methods for the determination of specific IGE antibodies against OLE E 7

Concordance study between two analytical methods for the determination of specific IGE antibodies against OLE E 7

Basophil activation test in Hymenoptera venom allergy.

Before starting venom-specific immunotherapy (VIT), systemic sting reactions to Hymenoptera venoms require allergological workup in order to prove an IgE-mediated reaction and to identify the culprit insect venom. In addition to skin tests and the determination of specific IgE antibodies, the basophil activation test (BAT) using flow cytometry has emerged as a powerful tool and sensitive marker for this purpose in recent years. BAT seems to have a better informative value in terms of clinical relevance compared to the other tests. In Hymenoptera venom allergies, BAT is particularly useful for the diagnosis of cases with unclear or contradictory history and sensitization profile. Its results are associated with adverse reactions during VIT and efficacy of VIT and therefore have a certain predictive value for side effects and treatment failure of VIT. In research, it is mainly used to characterize the allergenic components of Hymenoptera venoms. This review article focuses on these topics.

Allergic rhinitis: are there any problems? Case from clinical practice

Allergic rhinitis (AR) is found in the practice of doctors of various specialties, but making the correct diagnosis and prescribing adequate therapy can take many months and sometimes years. Currently, the problem of AR remains relevant, due to the extreme prevalence of AR, late diagnosis, underestimation of the possible risks of disease progression, complications, and the addition of such a formidable pathology as bronchial asthma. The path of the patient presented in the clinical case is quite typical for many patients with AR and concomitant pathology of nose. A young patient with allergic rhinitis received conservative treatment, and was later operated, but the effect was incomplete and short-lived. Only after 4 years, the patient was first examined by an allergist. Symptoms of AR indicate that the patient has an atopic status that promotes the involvement of various organs and systems in the inflammatory process. To verify the diagnosis and clarify the entire spectrum of “guilty” allergens, a specific allergological examination was carried out, which included skin testing and determination of specific IgE antibodies. The main participants in allergic inflammation are mast cells, eosinophils, lymphocytes, epithelial and endothelial cells. The effect of mediators on vascular endothelial cells and neuroreceptors of the nasal mucosa leads to the formation of allergic inflammation and the onset of clinical symptoms of AR. One of the main mediators released upon repeated contact with an allergen in a sensitized body is histamine, therefore antihistamines are first-line drugs at any stage of AR therapy. In our clinical case, taking into account complaints, medical history, clinical manifestations, results of laboratory (specific, nonspecific) and instrumental methods, the patient needs treatment of the corresponding first stage of therapy based on symptom control. The effectiveness of 2nd generation H1-antihistamines in the management of symptoms such as pruritus, sneezing, and rhinorrhea is due to histamine-mediated development of the early phase of the allergic reaction, which in turn leads to the onset of the late phase and the chronic co Bilastine can be considered as the drug that most fully meets the requirements of ARIA experts for 2nd generation H1-antihistamines : selective blockade of H1 receptors, high antiallergic effect, rapid onset of clinical effect, duration of action 24 hours, lack of tachyphylaxis and good tolerance. The results of the studies and their analysis show that bilastine is the preferred choice for monotherapy of allergic rhinitis.urse of allergic inflammation in the nasal mucosa.

Assessment of sensitization to grape and wine allergens as possible causes of adverse reactions to wine: a pilot study.

BackgroundIn a recently performed survey with 4000 randomly selected persons, 68 (7.2 %) of 948 respondents reported intolerance and/or allergy-like symptoms to wine. The aim of this study was to analyze whether a real sensitization to wine proteins could be confirmed by diagnostic and/or immunological settings.FindingsFor this purpose, 19 subjects with self-reported intolerance to wine of the invited subjects and 10 controls without a history of intolerance participated in an allergological examination (skin prick test, ImmunoCAP for determination of specific IgE antibodies, CAST for testing basophil activation, ImmunoBlot for testing specificity of IgE-antibodies). For the allergological work-up red and white grapes, selected wines, and the purified lipid transfer protein (LTP), a known grape allergen, were used. 7 subjects showed evidence of IgE sensitization to wine or grape extracts, including one control. One participant with symptoms of intolerance showed a positive skin prick test to red grape, a positive ImmunoCAP to grape, a positive cellular antigen stimulation test (CAST) and inhibition of Western blot by removal of cross-reactive carbohydrate determinants (CCD).ConclusionThe presented study focused on the grape protein-related IgE-mediated cause of intolerance to wine (true allergy) and not on other wine components or fining agents (other forms of intolerance). A sensitization to grape and wine proteins was observed in our cohort. In one case, this reactivity could be explained by cross-reactivity to CCD. The results of this pilot study need to be validated in greater cohorts.

The Impact of Environmental and Agricultural Pollutants on the Prevalence of Allergic Diseases in People from Qassim , KSA

There are multiple environmental factors that influence a sensitized (IgE antibody positive) patient's predisposition to manifest allergic symptoms following allergen exposure. The majority of allergens are known to induce morbidity with chronic symptoms such as rhinitis, pruritis, dermatitis and urticaria. To study the impact of environmental and agricultural pollutants with different pollens on the immunological, hematological and biochemical markers and to determine the prevalence of sensitization to allergens among exposed individuals as well as to identify the eliciting allergens. Ninety six highly exposed individuals to environmental and agricultural pollution in addition to 20 as controls were selected. A solid phase enzyme-linked immunosorbent assay and the EUROLINE test kit were used for the quantitative determination of total IgE concentration and semi-quantitative in vitro assay of human IgE antibodies to some of the inhalant, ingestant and contactant allergens in serum samples, respectively. Percentage and absolute eosinophil counts and biochemical parameters were analyzed. Thirteen (13.5%) out of the 96 studied highly exposed subjects were manifesting allergic symptoms. Higher significant total serum IgE levels and absolute eosinophil counts in groups 1 and 3 of the highly exposed individuals compared to the control group were found (p1=0.00, p3=0.001 and p1=0.016, p3=0.028, respectively). Higher sensitization with inhalant Timothy grass, Aspergillus fumigatus, Der. Farinae and Olive; ingestant Egg yolk, Mango, Strawberry and Codfish and with contactant Latex/plastic and Crude oil was found in the studied groups compared with the controls. The present data suggest that the highly exposed subjects to pollution are at high risk of developing an allergy. For the screening of those with suspected allergen sensitization, the determination of specific IgE antibodies is a suitable marker of type I allergy.

A new basophil activation test using CD63 and CCR3 in allergy to antibiotics

Flow cytometric basophil activation tests (BAT) have been developed as cellular tests for in vitro diagnosis of IgE-mediated reactions. Different markers and techniques have been used after stimulation with various allergens. It was the aim of the present study to compare an established BAT (Flow-CAST) with a newly developed basophil activation protocol using CD63 and CCR3 (Flow2 CAST) in patients with type-I allergy to antibiotics. Twenty-four patients with a history of type-I allergy to antibiotics were examined. A careful allergy history was taken, and skin tests and determination of specific IgE antibodies were performed. Two different BAT using CD63 expression but different protocols were carried out after stimulation with different concentrations of antibiotics. Fifteen healthy subjects without a history of antibiotic allergy were studied as controls. The Flow2 CAST showed a higher sensitivity than the Flow-CAST (55% vs. 53%) with regard to patients' history. Specificity was 80% both for the Flow2 CAST and for the Flow-CAST with regard to controls with negative history and negative RAST. These results show the value of two different BAT as cellular tests in the in vitro diagnosis of patients with antibiotic allergy with equal specificity and a slightly higher sensitivity for the Flow2 CAST.

Application of multiplexed immunoglobulin E determination on a chip in component‐resolved diagnostics in allergy

Cite this as: E. F. Knol and A. C. Knulst, Clinical & Experimental Allergy, 2010 (40) 190–192.

Perfil de sensibilización alérgica en niños de 0 a 5 años con sibilancias o dermatitis atópica

Background Although allergic diseases are frequent in childhood, few studies have characterised the IgE sensitization profile among young children with allergic-like symptoms. Objective To determine the prevalence and the type of allergic sensitization, as well as the demographic and environmental factors related to both characteristics, among 0–5 year old children presenting with wheezing and/or atopic dermatitis. Methods Collaborative cross-over study developed in the paediatric setting of 20 Spanish Primary Health Care Centres. An allergology evaluation including blood determination of specific IgE antibodies to common inhalant and food allergens was performed on 468 children who presented with wheezing and/or atopic dermatitis. Results Allergic sensitization was detected in 32.4% of the children with wheezing (95% confidence interval, 95%CI, 26.3–38.6%), in 54.8% of the children who had atopic dermatitis (95%CI, 42.1–67.6%) and in 39.2% of the children with both processes (95%CI, 32.0–46.4%). The risk of allergic sensitization was sex related (male versus female adjusted odds ratio, OR A, 1.91, 95%CI, 1.24–2.95), and also related to the age (3–5 versus 0–2 year old OR A 1.96, 95%CI, 1.27–3.0), type of early feeding (maternal milk versus infant formula OR A 0.51, 95%CI, 0.31–0.84) and geoclimatic area (OR A Continental versus Atlantic 2.26, 95%CI, 1.30–3.93). Compared to the Atlantic area, the Continental area the sensitization was lower to mites (OR A 0.16, 95%CI, 0.07–0.36) and higher to grass (OR A 4.65, 95%CI 1.99–10.86), cow milk (OR A 5.17, 95%CI, 1.71–15.62) and egg (OR A 5.26, 95%CI, 2.04–13.62), whereas in the Mediterranean area the sensitization was lower to mites (OR A 0.29, 95%CI, 0.13–0.64) and higher to cow milk (OR A 3.81, 95%CI, 1.20–12.14) and egg (OR A 5.24, 95%CI, 1.94–14.20). Conclusion A significant proportion of small children treated at the paediatric primary health care centres due to wheezing and/or atopic dermatitis had allergic sensitization. There appears to be a geoclimatic variation in the prevalence of sensitization to inhalant and food allergens among young children with allergic like symptoms who live in Spain.

Continued need of appropriate betalactam‐derived skin test reagents for the management of allergy to betalactams

Immediate allergic reactions to betalactams (BLs) are due to IgE antibodies that recognize the ring-derived penicilloyl determinant or side-chain structures of common BLs. The presence of specific IgE antibodies can be demonstrated by skin testing, the determination of specific IgE antibodies in sera or their binding to basophils with subsequent activation upon contact with penicillins in vitro. Skin tests are still the most sensitive technique followed by in vitro tests, which may sometimes yield useful complementary information. The diversity of the response to BLs has meant that in some instances, in addition to benzylpenicillin-derived determinants, testing for amoxycillin, cephalosporins or other BLs may also be required to establish the diagnosis. The recent withdrawal from the market of BL-derived materials for skin testing will have a serious effect on public health, resulting in a return to the pre-1960 era before these reagents became available. Because of their greater sensitivity, these skin tests cannot yet be replaced by in vitro tests. Furthermore, skin tests are the most readily available form of allergy testing for physicians. This paper reviews the results of skin tests in BL allergy and provides evidence for their continued need.

Comparison of basophil activation tests using CD63 or CD203c expression in patients with insect venom allergy

Flow cytometric basophil activation tests have been developed as cellular tests for in vitro diagnosis of IgE-mediated reactions. Different activation markers (CD63 or CD203c) with distinct ways of regulation have been used after stimulation with various allergens. It was the aim of the present study to compare basophil activation tests by measuring both CD63 and CD203c upregulation in patients with insect venom allergy. 43 patients with a history of insect venom anaphylaxis were examined. A careful allergy history was taken, and skin tests and determination of specific IgE-antibodies were performed. Basophil activation tests (BAT) using CD63 or CD203c expression were done after stimulation with different concentrations of bee and wasp venom extracts. 25 healthy subjects with negative history of insect venom allergy were studied as controls. The CD203c protocol showed a slightly higher sensitivity than the CD63 protocol (97% vs. 89%) with regard to patients' history. The magnitude of basophil response was higher with CD203c in comparison to CD63 for both insect venoms. Specificity was 100% for the CD63 protocol and 89% for the CD203c protocol with regard to controls with negative history and negative RAST. These results support the reliability of basophil activation tests using either CD63 or CD203c as cellular tests in the in vitro diagnosis of patients with bee or wasp venom allergy with a slightly higher sensitivity for the CD203c protocol.

Sinnhaftigkeit von IgG-Bestimmungen bei chronischen gastrointestinalen Beschwerden?

A 23-year-old patient has suffered from meteorism and occasional diarrhea for 8 years. Specific IgG antibodies directed towards multiple foods had been determined elsewhere. A concordant elimination diet had led to loss of body weight of 10 kg (remaining body weight 40 kg) without any improvement of the symptoms. At the time of first presentation in our Allergy Unit, a concise allergological work-up had not been performed. The skin prick testing of inhalant allergens, foods, spices, flour, preservatives and latex-associated foods showed 3+-positive reactions to grass pollen, rye pollen, dermatophagoides pteronyssinus, pepper, wheat flour and rye flour; 2+-positive reactions to curry, sodium proprionate and sorbic acid. Determination of specific IgE antibodies to rye flour, wheat flour, pepper and curry were negative, as well as serology for celiac disease. After dramatic weight loss due to elimination diet of 87 foods according to IgG antibodies identified elsewhere, positive prick test results were found to the above mentioned foods and food additives (pepper, wheat- and rye flour, curry as well as sodium proprionate and sorbic acid). A clinically relevant IgE-mediated allergy could be ruled out by an elimination diet to these positive tested foods that did not lead to any improvement of the clinical symptoms. A double-blind placebo-controlled food challenge (DBPCFC) to wheat and rye flour was refused by the patient. A Pillcam endoscopy revealed an inflammatory alteration of the mucous membran of the terminal ileum. Due to a suspected early stage of Crohn's disease, a coloscopy and a double-ballon endoscopy is scheduled. As in the presented case, determination of IgG antibodies raised against foods is not a feasible measure for diagnosis of gastrointestinal disorders and may lead to a significant delay in correct diagnosis and therapy of the underlying disease.

Food protein-induced Enterocolitis Syndrome Caused by Fish

Introduction Food protein-induced enterocolitis syndrome (FPIES) occurs in infants. Typical symptoms include profuse vomiting and/or diarrhea several hours after ingestion of a given food. The disorder is a non-IgE mediated food hypersensitivity. The most frequently involved foods are milk and soy, but some cases of FPIES induced by solid foods have been described. We report 14 patients with FPIES due to fish protein. Material and methods History and physical examination, skin prick test (SPT) with fish allergens and Anisakis simplex, prick-by-prick test with implicated fish and determination of specific IgE antibodies against fish were performed. In eight children atopy patch test (APT) were also performed. In nine patients an open oral food challenge with the implicated fish was carried out. Results There were six boys and eight girls, aged from 9 to 12 months at diagnosis, with between two and six reactions to the offending fish proteins before the diagnosis was established. Four patients had a previous history of atopy. Presenting symptoms included diarrhea in two patients, profuse vomiting in six patients, and recurrent vomiting and subsequent diarrhea in three patients. In addition to these symptoms, associated septic appearance, apathy and lethargy were present in the remaining three patients. Onset of symptoms occurred a few minutes after fish ingestion in two patients and from 60 minutes to 6 hours in the 12 remaining patients. SPT to fish were negative in all patients. Serum food-specific IgE antibodies were negative in all patients except one. APT was positive in three patients. Open oral challenge (OC) was performed in nine infants and was positive in all. The patients were followed-up for between 1 and 7 years after diagnosis, and follow-up OC tests were performed after fish had been eliminated from the patients’ diet for 3-4 years. Four patients became clinically tolerant to the causal food. Three patients currently tolerate only one type of fish (swordfish). Conclusions We report 14 patients with FPIES caused by fish protein. The symptoms suggest a form of cell-mediated, non-IgE mediated food hypersensitivity. The gold standard for diagnosis is OC, although caution should be exercised in infants with several reactions or a recent diagnosis. After a period of elimination of the causal food from the diet, tolerance can develop.

Anaphylaktischer Schock nach Ingestion von Pinienkernen

Pine nuts belong to the family of Pineaceae spp. and are widespread in the Mediterranean region. Allergy against pine nuts are rather rare up to now. We report a case of a male patient, showing a shock syndrom with mentalblackout after ingestion of pine nuts. The sensitization to pine nuts was investigated by means of the skin prick test (SPT), the determination of specific IgE antibodies, the cellular antigen stimulation test (CAST) and Westernblots. A self-produced pine nut extract and extracts of several nuts were used in the prick tests as well as in the CAP and CAST experiments. CAP inhibition assays were carried out using pine nut extracts with different protein concentrations. The determination of the characteristic proteins of the pine nut extract was performed by means of the SDS-Page/immunoblotting. The IgE-mediated sensitization to pine nuts was demonstrated clearly. Inhibition assay showed the homogenous inhibition of the specific IgE antibody up to 98% by the self-produced pine nut extract. An increased sulfidoleukotrien release (sLT) (2,400 -2,600 pg/ml) could be shown by the CAST experiments. The sLT values of the controls amounted under the background values. The characteristic pine nut allergen bands of 10, 30 and 47.5 kDa could be detected in the immunoblots. In conclusions, our patient demonstrated an isolated, IgE-mediated type C (according to Pichler's nomenclature) hypersensitivity to pine nuts. Because of the increasing use of pine nut in food, these proteins seem to become an important food allergen with increasing significance.

Relative utility of skin prick tests, total IgE and allergen-specific IgE in allergy diagnosis

Rationale The study assessed the correlation between skin prick test (SPT), determination of specific IgE antibodies and total serum IgE in patients with a history of allergic disorders. Methods 48 patients, 31 females and 17 males, age 16 to 65 years old were studied by SPT, total IgE and allergen-specific IgE. 27 patients had respiratory disorders, 15 had skin disorders and 6 had a history of systemic allergic reactions after insect stings. Results In 8 patients SPT and specific IgE were negative, 1 of whom had a slightly increased total IgE. In 8 patients SPT and specific IgE were positive, 4 of whom had increased total IgE. Among 10 patients who had dermographism and positive specific IgE, 6 had an elevated total IgE. 19 patients having negative SPTs had positive specific IgE assays, 9 also having a high level of total IgE. Conclusions There was no significant correlation between SPT and specific IgE tests, or between SPT and total serum IgE level. When SPT is positive and in agreement with the clinical history, the total and specific IgE add no additional useful information. However, in patients having dermographism or negative SPT, total and specific IgE determination may assist in confirmation of the diagnosis.

Allergic occupational dermatoses. Role of in vitro studies in diagnosis and prevention

Recently published guidelines only recommended in vitro assays for atopy screening by the determination of specific IgE antibodies in occupational cutaneous allergic diseases. However further indications include latex allergy, occupational drug allergy and wasp/ bee venom allergy. The lymphocyte transformation test may be an alternative to the patch test, in order to differentiate allergy from irritancy, or it may be an alternative to the patch test if hazardous compounds such as carcinogens are the possible antigens.

Ficus-benjamina-Allergie ohne Kreuzreaktivität zu Latex

Ficus benjamina is a plant very often used for indoor decorations that can generate allergies, e.g. rhinoconjunctivitis, urticaria and Quinke's edema as well as anaphylactic reactions. We report the case of a patient withhypersensitivity to Ficus benjamina without cross-reactivity to Natural Rubber Latex (NRL) or several fruits, like mango, banana and spinach, but with cross-reactivity to fig. The hypersensitivity to Ficus benjamina was investigated by means of the prick test, the determination of specific IgE antibodies, the cellular antigen stimulation test (CAST) and Westemblots. A self-produced Ficus benjamina extract, a Ficus benjamina extract from Allergopharma, extract of Hevea brasiliensis and extracts of several fruits were used in the prick tests as well as in the CAP and CAST experiments. CAP inhibition assays were carried out to study a suspected cross-reactivity of Ficus benjamina to NRL and several fruits, respectively. The hypersensitivity to Ficus benjamina was clearly demonstrated. Inhibition assay showed the inhibition of the specific IgE antibody up to 95%, and 82% by the self-produced Ficus benjamina extract and the commercial Ficus benjamina, respectively. Neither sensitization nor cross-reactivity to Hevea brasiliensis and several fruit proteins could be found, apart from cross-reactivity to fig. In our patient, an isolated type I hypersensitivity to Ficus benjamina with cross-reactivity to fig could be found, but without cross-reactivity to NRL. The Ficus benjamina protein seems to become an important indoor allergen with increasing significance.

Controlled administration of penicillin to patients with a positive history but negative skin and specific serum IgE tests.

Although subjects with a positive history of immediate allergy to penicillin and negative skin test are traditionally considered to tolerate penicillin, current evidence indicates that they may develop an immediate reaction despite negative skin and serum specific IgE tests. It is thought that these patients require additional tests to confirm the diagnosis. To assess in a large group of patients with a history of immediate allergy to penicillins but with both skin test and CAP-FEIA-negative to classical and side chain penicillin determinants, the role of controlled administration of betalactams as a diagnostic test. A group of 330 patients with a history of immediate allergic reactions to penicillins was studied by two evaluators from the same allergy unit using the following protocol: skin tests with major and minor determinants of benzylpenicillin (benzylpenicilloyl-poly l-lysine and minor determinant mixture), amoxicillin and ampicillin, and determination of specific IgE antibodies to penicillins, by CAP-FEIA, in serum. If both tests proved negative, a controlled administration of the drug was then carried out. A total of 89 (27%) patients were skin test and CAP-FEIA-negative and therefore required controlled administration of the drug. Of these, 49 developed an immediate response and were therefore considered allergic, and the remainder had good tolerance after administration of both benzylpenicillin and amoxicillin. The clinical characteristics of this group were similar to the other allergic patients who were skin test or CAP-FEIA-positive, except that they were younger (P < 0.01). Twenty-two (45%) developed a response to benzylpenicillin and 27 (55%) had a selective response to amoxicillin. Although all reactions appeared within 1 h, a positive correlation was found between the dose inducing the response and the time elapsed from drug administration, for both benzylpenicillin and amoxicillin (P < 0.001). These data indicate that an important number of subjects are not correctly identified if only skin tests and/or CAP-FEIA are used and that this is particularly relevant for side chain-specific reactions and younger subjects. This suggests that new diagnostic tests are required so as to limit the use of controlled administration.

Increased incidence of allergic sensitisation and respiratory diseases due to mould exposure: Results of the Leipzig Allergy Risk children Study (LARS)

AbstractTo investigate mould effects on health, the concentration of mould spores in air and dust was determined during a prospective cohort study. Clinical outcome was estimated by questionnaires and determination of specific IgE antibodies and intracellular cytokine production of T cells.A significant association was observed between the incidence of respiratory tract infections and exposure to Penicillium spores. Moreover, Aspergillus exposure was found to be associated with allergic rhinitis or related symptoms. In addition, T cells of children exposed to Aspergillus showed a significantly lower content of TH1 cytokines (IFN-γ, TNF-α, IL-2) producing cells. Our data suggest that mould exposure is associated with several effects on health, depending on the species involved.

Specific IgE levels in the diagnosis of immediate hypersensitivity to cows’ milk protein in the infant

Background: A milk-free diet with substitute formula should be established when immediate symptomatic hypersensitivity to cows’ milk protein (CMP) is diagnosed, and therefore an accurate diagnosis is very important. Objective: This study aims to find the optimal cutoff values for specific IgE antibody levels that discriminate between allergic and tolerant infants by using cows’ milk and its principal proteins as allergens. Methods: A prospective study was carried out on 170 patients under 1 year old (mean, 4.8 months). These patients were seen consecutively over a 4-year period in our outpatient clinic and for the first time because of a reaction suggesting immediate hypersensitivity after ingestion of cows’ milk formula. A clinical history, prick test with cows’ milk and its proteins (α-lact-albumin, β-lactoglobulin, and casein), determination of specific IgE antibodies with the CAP system FEIA for the same allergens as for the prick test, and a challenge test according to the diagnostic protocol were performed in all of the children. A study of validity of the prick test (cutoff point, 3 mm) and CAP system by using different cutoff points in the specific IgE values for cows’ milk and its proteins were also analyzed. Results: Prevalence of immediate symptomatic hypersensitivity to CMP in this study was 44%. When both the whole milk and its principal milk proteins were used in the prick test, the negative predictive value was very high, and a negative value excluded allergy in 97% of the patients. When the different cutoff points of the specific IgE for milk were analyzed, 2.5 KUA/L had a positive predictive value of 90% and 5 KUA/L had a positive predictive value of 95%. Conclusions: When diagnosing immediate hypersensitivity to CMP in infants, negative skin test responses exclude allergy in most of the patients. If the prick test response is positive, specific IgE levels for cows’ milk may be helpful. If these values are 2.5 KUA/L or greater, the challenge test should not be performed because of its high positive predictive value (90%). (J Allergy Clin Immunol 2001;107:185-90.)