Detection of Sensitization Profiles with Cellular In Vitro Tests in Wheat Allergy Dependent on Augmentation Factors (WALDA).

Wheat allergy dependent on augmentation factors (WALDA) is the most common gluten allergy in adults. IgE-mediated sensitizations are directed towards ω5-gliadin but also to other wheat allergens. The value of the different in vitro cellular tests, namely the basophil activation test (BAT) and the active (aBHRA) and passive basophil histamine-release assays (pBHRA), in the detection of sensitization profiles beyond ω5-gliadin has not been compared. Therefore, 13 patients with challenge-confirmed, ω5-gliadin-positive WALDA and 11 healthy controls were enrolled. Specific IgE (sIgE), skin prick tests, BATs, aBHRA, and pBHRA were performed with allergen test solutions derived from wheat and other cereals, and results were analyzed and compared. This study reveals a distinct and highly individual reactivity of ω5-gliadin-positive WALDA patients to a range of wheat allergens beyond ω5-gliadin in cellular in vitro tests and SPT. In the BAT, for all tested allergens (gluten, high-molecular-weight glutenin subunits, α-amylase/trypsin inhibitors (ATIs), alcohol-free wheat beer, hydrolyzed wheat proteins (HWPs), rye gluten and secalins), basophil activation in patients was significantly higher than in controls (p = 0.004-p < 0.001). Similarly, significant histamine release was detected in the aBHRA for all test substances, exceeding the cut-off of 10 ng/mL in all tested allergens in 50% of patients. The dependency of tests on sIgE levels against ω5-gliadin differed; in the pBHRA, histamine release to any test substances could only be detected in patients with sIgE against ω5-gliadin ≥ 7.7 kU/L, whereas aBHRA also showed high reactivity in less sensitized patients. In most patients, reactivity to HWPs, ATIs, and rye allergens was observed. Additionally, alcohol-free wheat beer was first described as a promising test substance in ω5-gliadin-positive WALDA. Thus, BAT and aBHRA are valuable tools for the identification of sensitization profiles in WALDA.

Placebo-Controlled Histamine Challenge Disproves Suspicion of Histamine Intolerance.

BACKGROUND: Histamine intolerance (HIT) is frequently diagnosed in patients with polysymptomatic otherwise unexplained symptoms. OBJECTIVES: To exclude HIT by a single-blind placebo-controlled histamine challenge (SBPCHC), to study clinical features of patients with positive challenge, and to examine the predictability of HIT by biomarkers. METHODS: SBPCHC was performed in 59 patients with suspected HIT. History and clinical data, including serum diamine oxidase (DAO) and histamine skin test wheal size of patients with positive versus negative SBPCHC, were compared. RESULTS: Patients were predominantly middle-aged women (84.7%). Three-quarters reported improvement but never resolution of symptoms during a histamine-low diet. Histamine provocation was safe; only 1 patient was treated with antihistamines. Thirty-seven patients (62.7%) displayed symptoms to placebo. HIT was excluded in 50 patients (84.7%). Objective symptoms occurred in 4 of 59 cases (6.8%) after histamine but not after placebo challenge. These were diagnosed with "plausible HIT" because reactions occurring by chance could not be excluded. Another 5 patients (8.5%) were diagnosed with "possible HIT" after case-dependent detailed analysis. Patients with plausible/possible HIT had reported more gastrointestinal symptoms (P = .01), but comparable diet response and equal histamine skin prick test wheal sizes to those without HIT. Serum DAO activity tended to be lower in patients with HIT (P = .08), but was highly variable in those without, limiting its value as a biomarker. CONCLUSIONS: SBPCHC disproves HIT in the majority of patients. Placebo-controlled challenges are needed as placebo reactions were frequent. Gastrointestinal symptoms after food intake and reduced DAO levels are markers for HIT; however, specificity is not sufficient enough for making the diagnosis.

Wheat-dependent exercise-induced anaphylaxis: subtypes, diagnosis, and management.

Wheat-dependent exercise-induced anaphylaxis (WDEIA) is an IgE-mediated food allergy with allergic symptoms ranging from intermittent urticaria to severe anaphylaxis that occurs when wheat ingestion is combined with augmenting cofactors such as exercise, non-steroidal anti-inflammatory drugs, or alcohol. In most cases, patients are identified by sensitization to ω5-gliadins in the gluten fraction of wheat. ω5-gliadin-negative subtypes of WDEIA are often difficult to diagnose and may be caused by Tri a 14 (wheat lipid transfer protein), after percutaneous sensitization with hydrolyzed wheat proteins, or, in rare cases, by cross-reactivity to grass pollen. Diagnosis is established based on the patients' history in combination with serum IgE profile, skin testing, basophil activation tests, and challenge tests with cofactors. Individual dietary counselling remains the central pillar in the management of WDEIA patients. A completely wheat-free diet is a possible option. However, this appears to promote tolerance less than continued regular consumption of gluten-containing cereals in the absence of cofactors. All patients should have an emergency set for self-treatment including an adrenaline autoinjector and receive adequate instruction. More data are needed on sublingual immunotherapy for WDEIA, a potentially promising therapeutic prospect. This article provides an overview of current knowledge on the diagnosis and management of WDEIA including an optimized challenge protocol using wheat gluten and cofactors.

Challenge-confirmed diagnosis restores quality of life in cofactor-dependent wheat allergy.

BACKGROUND: Food allergies including cofactor-dependent allergies such as cofactor-dependent wheat allergy (CDWA) decrease the quality of life (QOL) of patients. OBJECTIVE: To define the health-related QOL and fears in patients with CDWA and to evaluate the impact of diagnosis confirmation by oral challenge test (OCT). METHODS: Patients with CDWA diagnosed by clinical history, sensitization, and OCT were invited to participate. Clinical characteristics, patients' fears, self-perceived overall QOL, the Food Allergy Quality of Life Questionnaire-Adult Form score, and the risks and benefits of OCT were evaluated after the final diagnosis. RESULTS: A total of 22 adults with CDWA (13 male, 9 female; mean age 53.5 years; median 5 years until diagnosis) were included. Specific immunoglobulin E (IgE) levels for gluten proteins were inversely correlated with the reaction threshold (P < .05). Higher reaction severity in the patients' histories correlated with increased basal serum tryptase levels (P = .003) and gluten and gliadin specific IgE (P < .05), but not to QOL. After the first allergic reaction, patients reported a drop in QOL (P < .001). Challenge-confirmed diagnosis and medical consultation could restore the patients' QOL (P < .05) and reduce their fear of further reactions (P < .01). No severe reactions occurred during OCT, which was rated as not stressful and highly beneficial. Compared with patients with CDWA diagnosed without OCT in the literature, health-related QOL was less impaired (mean Food Allergy Quality of Life Questionnaire-Adult Form score 3.8), especially regarding the emotional impact (P < .001 vs existing literature). CONCLUSION: Until final diagnosis, patients with CDWA have a severe physical and psychological burden. OCT is a safe method to confirm the diagnosis, restore the patients' severely affected QOL, and reduce their fear of further reactions.

Cofactors of wheat-dependent exercise-induced anaphylaxis do not increase highly individual gliadin absorption in healthy volunteers.

BACKGROUND: In wheat-dependent exercise-induced anaphylaxis (WDEIA), cofactors such as exercise, acetylsalicylic acid (ASA), alcohol or unfavorable climatic conditions are required to elicit a reaction to wheat products. The mechanism of action of these cofactors is unknown, but an increase of gliadin absorption has been speculated. Our objectives were to study gliadin absorption with and without cofactors and to correlate plasma gliadin levels with factors influencing protein absorption in healthy volunteers. METHODS: Twelve healthy probands (six males, six females; aged 20-56 years) ingested 32 g of gluten without any cofactor or in combination with cofactors aerobic and anaerobic exercise, ASA, alcohol and pantoprazole. Gliadin serum levels were measured up to 120 min afterwards and the intestinal barrier function protein zonulin in stool was collected before and after the procedure; both were measured by ELISA. Stool microbiota profile was obtained by 16S gene sequencing. RESULTS: Within 15 min after gluten intake, gliadin concentrations in blood serum increased from baseline in all subjects reaching highly variable peak levels after 15-90 min. Addition of cofactors did not lead to substantially higher gliadin levels, although variability of levels was higher with differences between individuals (p < 0.001) and increased levels at later time points. Zonulin levels in stool were associated neither with addition of cofactors nor with peak gliadin concentrations. There were no differences in gut microbiota between the different interventions, although the composition of microbiota (p < 0.001) and the redundancy discriminant analysis (p < 0.007) differed in probands with low versus high stool zonulin levels. CONCLUSION: The adsorption of gliadin in the gut in healthy volunteers is less dependent on cofactors than has been hypothesized. Patients with WDEIA may have a predisposition needed for the additional effect of cofactors, e.g., hyperresponsive or damaged intestinal epithelium. Alternatively, other mechanisms, such as cofactor-induced blood flow redistribution, increased activity of tissue transglutaminase, or increases in plasma osmolality and acidosis inducing basophil and mast cell histamine release may play the major role in WDEIA.

Effects of structured patient education in adults with atopic dermatitis: Multicenter randomized controlled trial.

BACKGROUND: Atopic dermatitis (AD) is a chronic relapsing skin disease prevalent in 1% to 3% of adults in Western industrialized countries. OBJECTIVE: We sought to investigate the effectiveness of educational training in an outpatient setting on coping with the disease, quality of life, symptoms, and severity in adults with AD. METHODS: In this German prospective, randomized controlled multicenter study, adult patients with moderate-to-severe AD were educated by referring to a comprehensive 12-hour training manual consented by a multiprofessional study group from different centers (Arbeitsgemeinschaft Neurodermitisschulung für Erwachsene [ARNE]). Patients were randomly allocated to the intervention or waiting control groups. Study visits were performed at baseline and after 1 year (1 year of follow-up). Primary outcomes were defined as a decrease in (1) "catastrophizing cognitions" with respect to itching (Juckreiz-Kognitions-Fragebogen questionnaire), (2) "social anxiety" (Marburger Hautfragebogen questionnaire), (3) subjective burden by symptoms of the disease (Skindex-29 questionnaire), and (4) improvement of disease signs and symptoms assessed by using the SCORAD index at 1 year of follow-up. Data were analyzed on an intention-to-treat basis. RESULTS: At 1 year of follow-up, patients from the intervention group (n = 168) showed a significantly better improvement compared with the waiting group (n = 147) in the following defined primary study outcomes: coping behavior with respect to itching (P < .001), quality of life assessed by using the Skindex-29 questionnaire (P < .001), and the SCORAD index (P < .001). CONCLUSIONS: This is the first randomized, controlled multicenter study on patient education in adult AD. The ARNE training program shows significant beneficial effects on a variety of psychosocial parameters, as well as AD severity.

Educational programmes in food allergy.

About 17% of German children and adolescents suffer from at least one of the following atopic illnesses: allergic rhinoconjunctivitis, atopic eczema or asthma. Consistent professional therapy is necessary to limit the health-related risks and improve these medical conditions. The consequences of a diagnosis often mean an additional task for the parents of diseased children, where they have to act simultaneously as an educator and therapist for their children. Structured educational programmes were developed for a few diseases such as asthma and atopic eczema in order to prepare parents and affected children to accept this important responsibility. Moreover, a structured programme for anaphylaxis is being developed. These proposals aim not only to transfer knowledge about the disease but also to effectively support self-reliant treatment and emotional coping with the disease as well as its collateral strain.

Using a gluten oral food challenge protocol to improve diagnosis of wheat-dependent exercise-induced anaphylaxis.

BACKGROUND: Oral wheat plus cofactors challenge tests in patients with wheat-dependent exercise-induced anaphylaxis (WDEIA) produce unreliable results. OBJECTIVE: We sought to confirm WDEIA diagnosis by using oral gluten flour plus cofactors challenge, to determine the amount of gluten required to elicit symptoms, and to correlate these results with plasma gliadin levels, gastrointestinal permeability, and allergologic parameters. METHODS: Sixteen of 34 patients with a history of WDEIA and ω5-gliadin IgE underwent prospective oral challenge tests with gluten with or without cofactors until objective symptoms developed. Gluten reaction threshold levels, plasma gliadin concentrations, gastrointestinal permeability, sensitivities and specificities for skin prick tests, and specific IgE levels were ascertained in patients and 38 control subjects. RESULTS: In 16 of 16 patients (8 female and 8 male patients; age, 23-76 years), WDEIA was confirmed by challenges with gluten alone (n = 4) or gluten plus cofactors (n = 12), including 4 patients with previous negative wheat challenge results. Higher gluten doses or acetylsalicylic acid (ASA) plus alcohol instead of physical exercise were cofactors in 2 retested patients. The cofactors ASA plus alcohol and exercise increased plasma gliadin levels (P < .03). Positive challenge results developed after a variable period of time at peak or when the plateau plasma gliadin level was attained. Positive plasma gliadin threshold levels differed by greater than 100-fold and ranged from 15 to 2111 pg/mL (median, 628 pg/mL). The clinical history, IgE gliadin level, and baseline gastrointestinal level were not predictive of the outcomes of the challenge tests. The challenge-confirmed sensitivity and specificity of gluten skin prick tests was 100% and 96%, respectively. CONCLUSION: Oral challenge with gluten alone or along with ASA and alcohol is a sensitive and specific test for the diagnosis of WDEIA. Exercise is not an essential trigger for the onset of symptoms in patients with WDEIA.