Atopy Patch Test Research Articles

Treatment of eosinophilic esophagitis with specific food elimination diet directed by a combination of skin prick and patch tests

Eosinophilic esophagitis (EE) is a recently described disorder identified in patients with symptoms suggestive of gastroesophageal reflux disease (GERD) but unresponsive to conventional reflux therapies. Therapies have included corticosteroids, elemental diet, and diet restriction. We report our experience with skin prick and atopy patch testing and food elimination diets in patients diagnosed as having EE. To identify food antigens that cause EE and the characteristics of patients who respond to food elimination vs those who are unresponsive. Patients diagnosed as having EE had restricted diets based on skin prick and atopy patch testing results. Additional biopsies were performed after 4 to 8 weeks of restricted diet. Demographics, atopic tendencies, and food antigens were identified retrospectively in our food allergy database. A total of 146 patients diagnosed as having EE were evaluated with skin prick and atopy patch testing. Thirty-nine patients had unequivocal demonstration of food causing EE, with normalization of biopsy results on elimination and reoccurrence on reintroduction. An additional 73 patients, for a total 112 (77%) of 146 patients, had resolution of their EE as demonstrated by biopsy results. Fifteen (10%) of 146 patients were nonresponders manifested by no significant reduction in esophageal eosinophils despite restricted diet based on skin prick and atopy patch testing. Egg, milk, and soy were identified most frequently with skin prick testing, whereas corn, soy, and wheat were identified most frequently with atopy patch testing. In more than 75% of patients with EE, both symptoms and esophageal inflammation can be significantly improved with dietary elimination of foods. Skin prick and atopy patch testing can help identify foods in most patients.

Atopy patch test reactions in high‐IgE beagles to different sources and concentrations of house dust mites

Protocols for atopy patch testing (APT) were evaluated on six high-IgE dogs sensitized to house dust mites (HDM) using various concentrations and sources of HDM. Two sources of HDM were compared: Heska slurry and four concentrations of Greer HDM. Saline was used as a negative control. Patches were removed after 48 h and the sites evaluated at 0, 6, 24, 48, 72 and 96 h for erythema, macules, papules and pustules. Each sign was scored from 0 to 3 (0 = absent and 3 = severe). Total score was used for analysis. Mean total scores significantly increased for both Greer and Heska HDMs from 6 h, peaking at 48 h for G100 (100 mg mL(-1)), G300 and G668, and at 72 h for Heska and G31.25. Across all times, Heska HDM scores were significantly higher than those of G31.25 with the largest difference at 96 h. Heska scores, however, were significantly lower than those of other Greer concentrations (G100, G300 and G668) particularly at 96 h. No reactions were noted at saline sites. It is concluded that Greer-HDM at 100 mg mL(-1) is the most suitable concentration for APT in dogs because it induces reactions comparable if not higher than more concentrated HDM preparations.

Atopy patch testing with aeroallergens in patients with atopic dermatitis and controls in Singapore

The role of allergy in atopic dermatitis is controversial. The atopy patch test (APT) has been used to investigate the association between atopic dermatitis and aeroallergen allergy. To determine the proportion of patients with atopic dermatitis with positive patch tests to common local aeroallergens and to compare this to controls with and without respiratory atopy, we performed APT, skin-prick tests (SPT) and IgE radioallergosorbent tests (RAST) on 73 patients with atopic dermatitis and on 38 nonatopic controls (13 with and 25 without respiratory atopy). The allergens used were house dust mite, cat dander, Bermuda grass and German cockroach. Only the APT for house dust mite showed a significant difference between the two groups. APT for house dust mite correlated with the RAST test, while APT for cat fur correlated with the SPT. The APT may be useful to evaluate aeroallergens in atopic dermatitis, but further work is needed to make it more reliable.

Skin Localization of Cow’s Milk Proteins Delivered by a New Ready-to-Use Atopy Patch Test

Atopy patch tests (APTs) allow the detection of delayed allergies at the skin level. The localization of beta-lactoglobulin delivered into the skin by an innovative ready-to-use APT (E-patch was investigated and the efficacy and safety of this device were assessed. The E-patch containing beta-lactoglobulin was placed for 24 h in contact with hairless rat skin mounted in a Franz diffusion cell. Transdermal passage was monitored by measurement of beta-lactoglobulin A-[methyl-(14)C] or by two-site enzyme immunoassay. An iterative skin stripping allowed measurement of the beta-lactoglobulin penetrating the first external skin layers. After 24 h, 92% of beta-lactoglobulin remained on the skin. The iterative skin strippings showed a 135-fold higher concentration of beta-lactoglobulin in the stratum corneum than that found in the epidermis-dermis. Analysis of the solution in the receiver compartment by radioactivity assays or immunoassays indicates that intact protein did not cross the skin. The E-patch system allows native beta-lactoglobulin to concentrate in the stratum corneum, in the vicinity of immunological cells, but does not lead to its systemic delivery. Therefore, it is suggested that this delivery system creates ideal conditions for promoting a positive topical response with reduced risk of systemic anaphylactic reactions caused by the native form of the beta-lactoglobulin A.

Controlled oral food challenges in children – when indicated, when superfluous?

The diagnostic work-up of suspected food allergy includes the skin prick test (SPT), the measurement of food specific immunoglobulin E (IgE) antibodies using serologic assays, and more recently the atopy patch test (APT). For specific serum IgE and the SPT, decision points have been established for some foods allowing prediction of clinical relevance in selected cases. The APT may be helpful, especially when considered in combination with defined levels of specific IgE. Controlled oral food challenges still remain the gold standard in the diagnostic work-up of children with suspected food allergy. Most food allergic children will lose their allergy over time. As there is no laboratory parameter, which can accurately predict when clinical tolerance has been developed, controlled oral food challenges are the measure of choice. In this article, the current knowledge of predictors for the outcome of oral food challenges is reviewed and proposals for the daily practical work-up in the case of suspected food related clinical symptoms are presented.

Food allergy diagnostics: scientific and unproven procedures

The accurate diagnosis of food allergy is crucial not only for the right treatment but also for the avoidance of unnecessary diets. The diagnostic work-up of suspected food allergy includes the measurement of food-specific IgE antibodies using serologic assays, the skin prick test, elimination diets and oral provocation tests. In addition, some approaches are either under further rigorous investigation (the atopy patch test) or are already in widespread use, particularly by practitioners of alternative or complementary medicine, but are considered unproven. These diagnostic methods include specific IgG to foods, provocation/neutralization testing, kinesiology, cytotoxic tests and electrodermal testing. This review covers some of the most common scientifically validated and unproven approaches used in the diagnosis of food allergy. For specific serum IgE and the SPT, decision points have been established for some foods, allowing prediction of clinical relevance. The APT may be helpful, especially when considered in combination with defined levels of specific IgE. In regard to other approaches, most scientific studies do refute the usefulness of these approaches. In most patients, controlled oral food challenges remain the gold standard in the diagnostic work-up of suspected food allergy. The skin prick test and measurement of specific IgE antibodies to food extracts, individual allergens or allergenic peptides are helpful in the diagnostic approach. Food-specific IgG continues to be an unproven or experimental test. The other alternative and complementary techniques have no proven benefit and may endanger patients via misdiagnosis.

Das nicht-atopische (intrinsische) Ekzem

Atopic dermatitis (AD) is a chronic relapsing, inflammatory skin disease, caused by a genetic predisposition and a variety of environmental triggers. In most cases, AD is linked to a specific IgE immune response to commoninhalants or food allergens and therefore classified as an atopic subtype, the so-called atopic eczema (AE). However, in up to 30% of patients with AD, there are normal serum IgE levels and negative skin tests; as a result, the term non-atopic eczema (NAE) has been proposed to replace the otherwise used terms intrinsic or non-IgE-associated form of AD. Facing this constellation, solely atopy patch tests, which elicit eczematous skin reactions after epidermal application of common aeroallergens, may indicate a putative role of local T cell response in the skin and, thus, are highly important in NAE. Next to a certain genetic disposition, infectious triggers and autoreactivity in patients with NAE have been observed. In the following, we will present a short overview to highlight typical characteristics in NAE and possible pathogenic factors in this AD subtype.

Evaluation of the utility of atopy patch testing, skin prick testing, and total and specific IgE assays in the diagnosis of cow's milk allergy

Information on the utility of atopy patch testing (APT) in the diagnosis of food allergy is derived from studies of children with atopic dermatitis. To evaluate the usefulness of APT in the diagnosis of cow's milk allergy (CMA) and to determine interleukin 4 and interferon-gamma production by peripheral blood mononuclear cells. Thirty-seven children (median age, 11 months) with suspected CMA who had a variety of symptoms that involved many organ systems were evaluated using double-blind placebo-controlled food challenges (DBPCFCs), and the performances of milk specific IgE, skin prick testing (SPT), and APT were determined. To search for a possible relationship between the diagnostic tests and the TH1/TH2 immune response, we measured interferon-gamma and interleukin 4 levels in the supernatants of peripheral blood mononuclear cell cultures. Seventeen children with positive DBPCFC results and 6 with a history of anaphylaxis were diagnosed as having CMA. The combined use of APT and SPT had a sensitivity of 100% and a negative predictive value of 100% but a specificity of 50% and a positive predictive value of 76%. The addition of milk specific IgE assays to APT and SPT did not improve these values. Pattern of cytokine secretion was not associated with APT positivity or a specific response to DBPCFC. Atopy patch testing may be a useful adjunct to SPT in excluding CMA in children who have allergic manifestations other than atopic dermatitis. However, DBPCFCs are still necessary in the presence of positive test results.

IgE-mediated and T cell–mediated autoimmunity against manganese superoxide dismutase in atopic dermatitis

Autoreactivity of patients with atopic dermatitis (AD) to human proteins has been postulated as a decisive pathogenetic factor for AD. In this study, it was investigated whether the stress-inducible enzyme manganese superoxide dismutase (MnSOD) of human and fungal origin might act as an autoallergen in atopic dermatitis. Patients with AD (n = 69; mean SCORAD [SCORing Atopic Dermatitis], 27) and other inflammatory skin diseases as well as with inhalant allergies were investigated. The presence of specific IgE against recombinant MnSOD of fungal and human origin and the fungal extracts of Aspergillus fumigatus and Malassezia sympodialis was measured by CAP, ELISA, skin prick test, and in subset of patients also by atopy patch tests (APTs) and PBMC proliferation assays. Cross-reactivity between allergens was determined by CAP inhibition. The presence of MnSOD in human skin in various inflammatory skin conditions was investigated by immunohistochemistry. Specific IgE antibodies against human MnSOD correlating with the disease activity were found in 29 out of 67 patients with AD. The human protein was able to induce in vitro T-cell reactivity and eczematous reactions in APT in MnSOD-sensitized patients with AD. MnSOD was upregulated in various inflammatory skin reactions and APT skin specimens. Cosensitization to structurally related and cross-reacting fungal MnSOD and the skin-colonizing yeast M sympodialis was observed in all patients sensitized against human MnSOD. Human MnSOD may play a role as an autoallergen in a subset of patients with AD, including nonatopic eczema. By molecular mimicry leading to cross-reactivity such sensitization might be induced primarily by exposure to environmental fungal MnSOD of M sympodialis .

Psoriasiform contact dermatitis due to propolis in a beekeeper

More than 250 cases of allergic contact dermatitis due to propolis have been described. A few of these occurred in beekeepers. To describe a case of psoriasiform dermatitis caused by propolis in a beekeeper who thought that his lesions were related to honeybee stings. A 45-year-old beekeeper experienced hand dermatitis for the past 5 years. He believed that the lesions occurred and worsened when he was stung by honeybees. He was prescribed topical corticosteroids several times, but because he was stung frequently, the drugs never helped control the lesions. In the past few years, he frequently had contact with propolis during honey collection, but he denied the role of propolis because he was wearing gloves while handling the beehives. For diagnostic evaluation, skin biopsy, skin prick tests (SPTs), identification of specific IgE antibodies, and atopic patch tests were performed. Skin biopsy showed psoriasiform contact dermatitis. Results of SPTs to honeybee and serum specific IgE for Apis mellifera remained negative. Results of the atopic patch test performed using A mellifera SPT material were also negative in the first 20 minutes and on the second and third days. However, propolis showed a positive erythematopapular reaction on day 2. The patient never again worked as a beekeeper, and neither did he, as far as he knew, use any medical or cosmetic products that contained propolis. His hand lesions improved almost completely. Dermatitis due to propolis should never be disregarded in beekeepers, and every effort should be put forth to make a correct diagnosis and to convince the patients of the cause.

Quoi de neuf en allergologie pédiatrique en 2004 ? Partie 3 : allergie cutanée, alimentaire, médicamenteuse et aux venins d'insectes (Une revue de la littérature internationale d'octobre 2003 à septembre 2004)

Severity and risk of persistence/relapse of atopic dermatitis are correlated with total IgE levels and food sensitization. Weaning to hypoallergenic formula improves SCORAD and gut barrier function in breastfed infants with persistent atopic dermatitis. Risk of anaphylaxis is high in children with cold-induced urticaria, and these children should be provided with an epinephrine autoinjector. Occult sensitizations are important risk factors for food allergy. The predictive values of serum egg-specific IgE levels are debated. The diagnostic value of atopy patch-tests with foods is confirmed in children with non-immediate food hypersensitivity reactions. Risk of persistence of food allergy is high in children with high specific IgE levels and/or with a low rate of decrease in food-specific IgE levels. Oral desensitization induces tolerance in children with persistent cow's milk allergy, except for children with very high levels of specific IgE. However, tolerance to anaphylactogenic food may be temporary, with the occurence of severe relapses after a few months. Ten per cent of children treated with penicillins are sensitized to these antibiotics. However, only a few of these children are at risk of developing allergy to penicillins. Non allergic hypersensitivity to non steroidal anti-inflammatory drugs is frequent in children. Sublingual immunotherapy may be efficient in children with latex hypersensitivity. A clinically important number of non-hyposensitized children do not outgrow hymenoptera venom allergy. In contrast, venom immunotherapy leads to a significantly lower risk of systemic reaction to stings. Thus, children with moderate to severe allergic reactions to hymenoptera stings should receive specific immunotherapy.

Atopy Patch Test Reactions to House Dust Mites in Patients with Scabies

It is well known that the house dust and the scabies mites are related phylogenetically. We therefore performed atopy patch tests with house dust mite antigens (Dermatophagoides pteronyssinus (Dp) and/or Dermatophagoides farinae (Df)) in scabies patients without atopy and healthy controls. We studied 25 men with active scabies and 25 healthy controls. Skin prick tests with standardized house dust mite extract were performed for all patients and controls. An intradermal test procedure was carried out in skin prick test-negative patients, and for controls showing positive atopy patch test to Dp and/or Df. While atopy patch tests were performed directly in all healthy controls, patients with scabies were first treated and on the next day, atopy patch tests were performed. Twenty-two of 25 patients with scabies (88%) had skin prick test and/or intradermal test positivity against house dust mites, whereas 17/25 patients (68%) had atopy patch test positivity against house dust mites (Dp and/or Df). There was no statistically significant difference between skin prick test and/or intradermal test positivity and atopy patch test positivity in a regression analysis (p=0.222). The only statistically significant correlation was between atopy patch test positivity and the extent of scabies involvement (p<0.05). Only few of the healthy controls had positive tests. In this study, we have shown that a positive atopy patch test to house dust mite antigens is not specific for patients with atopic dermatitis, but also occurs in scabies patients without a history of atopic dermatitis.

Atopy Patch Test – Reproducibility and Elicitation of Itch in Different Application Sites

We evaluated the reproducibility of atopy patch test reactions and the quality and quantity of itch in 16 patients with atopic eczema and a history of a positive atopy patch test reaction, comparing three different application sites. The allergen was re-applied simultaneously on both forearms and the back. Intensity and quality of pruritus were evaluated using a visual analogue scale and the Eppendorf itch questionnaire, respectively. The atopy patch test reaction was highly reproducible, occurring in 15/16 (94%) patients. Pruritus was reported by 14/16 (88%) patients. There was no significant difference in either the intensity or quality of itch between the two forearms and the back (p>0.05). The mean peak visual analogue scale itch score was comparable across all three test sites (range 28.3-31.9). Regarding quantification of test reactions, a positive reaction was more frequent on the back (94% versus 69% on the arms) and the peak atopy patch test score was higher on the back compared with the arms (right forearm, p=0.0018 and left forearm, p=0.0683). Allergens should preferably be applied on the back for the atopy patch test. However, the atopy patch test can induce atopic itch irrespective of the application site.

Patch Testing with Egg Represents a Useful Integration to Diagnosis of Egg Allergy in Children with Atopic Dermatitis

Our aim was to investigate atopy patch and skin prick test reactions to egg in 85 children with atopic dermatitis, and to evaluate their relevance by performing repeated open challenges with egg. Thirty-one percent of our patients showed an eczematous response to the challenge. Positive reactions to atopy patch and skin prick tests were recorded in 37% and 19%, respectively. Atopy patch test sensitivity proved significantly higher than that of skin prick test (79.6% vs. 46.2%), whereas specificity was lower (81.4% vs. 93.2%). Our data suggest that combined skin prick and patch testing improves screening for egg allergy in affected children, identifying 92% of those who were challenge positive among our patients.

Aktuelles zur atopischen Dermatitis (Neurodermitis)

Atopic dermatitis (AD) or atopic (AE) is a multifactorial skin disease caused by a variety of factors such as genetic conditions, alterated skin structure, immunologic deviations and environmental factors, among others. According to the new WAO nomenclature, the term eczema should be used as the umbrella term to cover all different subtypes of atopic dermatitis, i.e. the IgE-associated (atopic eczema) and the non-IgE-associated type (non-atopic eczema). Besides some comments on the new nomenclature and the so-called march, we provide an overview of the diagnostic importance of atopy patch tests, especially in the formerly called intrinsic type of AE and the role of Staphylococcus aureus-enterotoxins with superantigenic activity, and of fungi (Coprinus comatus and Malassezia furfur sive sympodialis) as illness-specific allergens in AD/AE. The use of antiinfectious and antifungal drugs (topic or systemic) may be of notable benefit in some AD/AE patients. Especially in children with AD/AE, is easily aggravated by contact with irritating factors (e.g. aggressive detergents, synthetic and woolen clothes). Also, skin colonization with Staphylococcus aureus is known as a major trigger of the disease. Silver-coated textiles and a silk fabric coated with AEGIS AEM 5772/5, an antimicrobial substance, efficiently reduce Staphylococcus aureus colonization in patients with AD/AE. Some new studies even have shown a superior improvement by treatment with silver-coated textiles or specially manufactured silk clothes compared to cotton textiles or mild topical corticosteroids. Finally, the development of a new class of steroid-free, topic immunomodulatory drugs (tacrolimus and pimecrolimus) has substantially improved the treatment of AD/AE. Nevertheless, patient education is still very important in the management of the disease since it often follows an unpredictable course.

Skin localisation of cow's milk proteins delivered by a new ready-to-use APT

RATIONALE: Atopy patch tests (APTs) allow the detection of delayed allergic reactions. An experimental model was designed to investigate the transdermal passage of β-lactoglobulin delivered into the skin by an innovative ready-to-use APT (E-patch®) and to assess the efficacy and safety of this device.

Usefulness of atopy patch test in diagnosis of food allergy in children with atopic dermatitis

RATIONALE: Food allergens have been shown to play significant role in exacerbation and maintenance of eczematous lesions in children with atopic dermatitis. The atopy patch tests (APT) seems to be a valuable tool in the diagnosis of food allergies, especially non IgEmediated.

Usefulness and safety of a ready-to-use atopy patch test (APT) (Diallertest®) versus a reference test (Finn Chamber®) during cow's milk allergy in children

Usefulness and safety of a ready-to-use atopy patch test (APT) (Diallertest®) versus a reference test (Finn Chamber®) during cow's milk allergy in children

Standardizing the interpretation of atopy patch testing to food in children

Standardizing the interpretation of atopy patch testing to food in children

Atopy patch test for the diagnosis of food protein-induced enterocolitis syndrome

Atopy patch test for the diagnosis of food protein-induced enterocolitis syndrome