vitamin D; calcitriol; immune system
Non-IgE-mediated food allergic disorders account for up to 40% of milk protein allergy in infants and young children. We aim to review the recent literature and to provide an update on diagnosis and management of food protein-induced enterocolitis syndrome (FPIES) and food protein-induced allergic proctocolitis (FPIAP). The peer-reviewed articles indexed in PubMed have been reviewed. FPIES manifests in infants as profuse, repetitive vomiting and lethargy, often with diarrhea, leading to acute dehydration, or weight loss and failure to thrive, in chronic form. FPIES is caused most commonly by cow's milk (CM) and soy proteins; rice, oat, and other solid foods may also trigger FPIES. FPIES rarely occurs in the exclusively breastfed infants. FPIES is underrecognized; children are often mismanaged as having acute viral gastrointestinal illness, sepsis, or surgical disease, delaying diagnosis of FPIES for many months. Approximately 25% of children with FPIES develop food-specific IgE antibodies and some transition to immediate food allergy; IgE positivity is associated with a more protracted course. FPIES is a self-limiting condition, with most cases resolving by age three to five years. Ondansetron may be helpful in managing acute FPIES. FPIAP is a benign condition of bloody stools in a well-appearing infant, with usual onset between one and four weeks of age. Up to 60% of cases occur in exclusively breastfed infants and resolve with maternal elimination of CM and soy proteins. The majority of cases resolve by age 12 months. FPIES may transition to IgE-mediated food allergy in some patients; IgE positivity to the FPIES food is a marker of a more persistent disease. FPIAP is benign and resolves by age 12 months in most patients.
Food allergy; food protein-induced enterocolitis syndrome; food protein-induced allergic proctocolitis; cow's milk allergy; soy allergy; non IgE-mediated food allergy; allergic enteropathy
Modification of native peanut extracts could reduce adverse effects of peanut immunotherapy.
We sought to compare native and chemically modified crude peanut extract (CPE) and major peanut allergens Ara h 2 and Ara h 6 in a mediator-release assay based on the rat basophilic leukemia (RBL) cell line transfected with human Fcε receptor.
Native Ara h 2/6 was reduced and alkylated (RA), with or without additional glutaraldehyde treatment (RAGA). CPE was reduced and alkylated. Sera of subjects with peanut allergy (16 males; median age 7 years) were used for overnight RBL-passive sensitization. Cells were stimulated with 0.1 pg/mL to 10 μg/mL of peanut. β-N-acetylhexosaminidase release (NHR) was used as a marker of RBL degranulation, expressed as a percentage of total degranulation caused by Triton X.
Median peanut-specific immunoglobulin E was 233 kUA/L. Nineteen subjects were responders, NHR ≥ 10% in the mediator release assay. Responders had reduced NHR by RA and RAGA compared with the native Ara h 2/6. Modification resulted in a later onset of activation by 10- to 100-fold in concentration and a lowering of the maximum release. Modified RA-Ara h 2/6 and RAGA-Ara h 2/6 caused significantly lower maximum mediator release than native Ara h 2/6, at protein concentrations 0.1, 1, and 10 ng/mL (p < 0.001, < 0.001, and < 0.001, respectively, for RA; and < 0.001, 0.026, and 0.041, respectively, for RAGA). RA-CPE caused significantly lower maximum NHR than native CPE, at protein concentration 1 ng/mL (p < 0.001) and 10 ng/mL (p < 0.002). Responders had high rAra h 2 immunoglobulin E (mean, 61.1 kUA/L; p < 0.001) and higher NHR in mediator release assay to native Ara h 2/6 than CPE, which indicates that Ara h 2/6 were the most relevant peanut allergens in these responders.
Chemical modification of purified native Ara h 2 and Ara h 6 reduced mediator release in an in vitro assay ∼100-fold, which indicates decreased allergenicity for further development of the alternative candidate for safe peanut immunotherapy.
Food allergy; peanut allergy; Ara h 2; Ar a h 6; mediator-release assay; RBL; rat basophil leukemia cell line; NHR; N-hexosaminidase release; allergenicity; hypoallergenic peanut
Carbohydrate moieties of different glycoproteins, such as cross-reactive carbohydrate determinants (CCDs) and galactose α-1,3-galactose, can induce IgE reactivity with varied clinical significance. In this study, the possible participation of glycan from wheat gliadin, with respect to its IgE-binding capacity, was investigated in children with food allergies to wheat. Total IgE and wheat-specific IgE quantification, documentation of history, and/or oral food challenge (OFC) were performed for 52 children. Subjects with positive wheat-specific IgE were characterized as the symptomatic group, never-exposed group, or asymptomatic group. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and glycan detection in gliadin were performed. IgE binding to gliadin and deglycosylated gliadin was measured by immunoblotting and ELISA. Gliadin-specific IgE was detected and correlated with wheat-specific IgE in the symptomatic, never-exposed, and asymptomatic groups. The glycan range overlapped significantly with the gliadin range. Deglycosylation of gliadin reduced the allergenicity of gliadin. In gliadin, the allergenicity of the glycan portion was greater in the symptomatic group than in the never-exposed and asymptomatic groups. We conclude that N-glycan in gliadin might exhibit allergenicity as a possible carbohydrate epitope in wheat allergy in children.
Carbohydrate epitope; cross-reactive carbohydrate determinants; deglycosylation; food allergy; immunoglobulin E reactivity; gliadin; glycan; glycoprotein; oral food challenge; wheat allergy
The risks of using leukotriene receptor antagonists (LTRA) as part of a strategy for stepping down inhaled corticosteroid (ICS) are not well known.
To estimate the risk of asthma exacerbation in individuals with stable asthma who start LTRA when stopping ICS or reducing ICS dose.
We identified articles from a systematic review of English and non-English articles by using a number of data bases. We included randomized controlled trials with a stable asthma run-in period of 4 weeks or more and a follow-up period of at least 3 months. We included studies of individuals with stable asthma who stopped ICS and substituted LTRA (versus continuing ICS) and who reduced ICS while starting LTRA (versus placebo).
The search strategy identified 1132 potential articles, of which 52 were reviewed at the full-text level, and four met criteria for inclusion. The single article that met the inclusion criteria for substitution of LTRA for ICS as a step-down strategy found a statistically increased risk of treatment failure of 30.3% for substituting LTRA compared with 20.2% for continuing ICS. The three articles that met the inclusion criteria for comparing LTRA versus placebo in patients with stable asthma who reduce ICS found a modestly decreased risk ratio that favored LTRA of 0.57 (95% confidence interval, 0.36–0.90; I2 = 0%) in studies that only included individuals >15 years old.
Only one study addressed the risk of substitution of LTRA for ICS in stable asthma, which limited any strong conclusions about this step-down strategy.
Asthma; antiasthmatic agents; glucocorticoids; leukotriene antagonists; clinical trial; step down; withdraw; decrease; wean
Hereditary angioedema (HAE) is a rare autosomal-dominant disease characterized by recurring attacks of nonpruritic, nonpitting edema caused by an inherited deficiency or dysfunction of C1 esterase inhibitor (C1 INH). Symptoms can present years before an accurate diagnosis is made. The objective of this study, the Angioedema Clinical Epidemiology Testing Initiative for the Study of Hereditary Angioedema, was to determine the prevalence and clinical manifestations of HAE in untested first-degree blood relatives of known patients with HAE. Patients with a confirmed diagnosis of HAE recruited first-degree relatives who had not been evaluated for HAE. Enrolled subjects underwent complement testing (C4, C1 INH antigen, and functional C1 INH). If the lab tests were abnormal, the enrolled subjects returned to the site for a follow-up visit and questionnaire. Overall, 31 patients with HAE and 46 first-degree relatives enrolled in the study. Of 46 enrolled relatives, 30 (65%) had lab test results that ruled out a diagnosis of HAE, two (4%) were categorized as “HAE not ruled out,” and 14 (30%) were newly diagnosed with HAE. Of 14 newly diagnosed subjects, nine (64%) reported having experienced symptoms that may have been related to HAE, such as swelling in the throat, face, or extremities or abdominal pain. When reported, median age of symptom onset in these 14 subjects was nine years whereas newly diagnosed asymptomatic subjects had a median chronological age of six years. These 14 subjects reported a historic mean standard deviation rate of 2.51 (5.59) swelling episodes per month with a mean standard deviation duration of 1.6 (0.74) days. This study's findings reinforce the importance of testing family members of patients with HAE to detect this hereditary condition.
First-degree relatives; C1 inhibitor antigen; C1 esterase deficiency; functional C1 inhibitor; questionnaire; epidemiology; diagnosis; hereditary angioedema
Hereditary angioedema (HAE) is a chronic disease with a high burden of disease that is poorly understood and often misdiagnosed. Availability of treatments, including C1 esterase inhibitor (C1INH) replacement, ecallantide, and icatibant, marks a significant advance for HAE patients. We aimed to better understand the current state of HAE care, from a patient perspective, after the introduction of several novel therapies. One session of the United States Hereditary Angioedema Association 2013 patient summit was devoted to data collection for this study. Patients attending the summit were self-selected, and HAE diagnosis was self-reported. Survey questions assessed patient characteristics, burden of disease, and treatment. Participant responses were captured using an audience response system. We surveyed 149 (80%) type I and II HAE (HAE-C1INH) and 37 (20%) HAE with normal C1INH (HAE-nlC1INH) patients. HAE-C1INH (72%) and HAE-nlCINH patients (76%) equally reported that HAE had a significant impact on quality of life (QOL). A third of HAE-C1INH patients were diagnosed within one year of their first HAE attack, but another third reported a delay of more than 10 years. Most HAE-C1INH (88%) and HAE-nlC1INH (76%) patients had on-demand treatment available. HAE-C1INH patients frequently had an individual treatment plan (76%) compared with 50% of HAE-nlC1INH patients. Most HAE-C1INH patients went to the emergency department (ED) or were hospitalized less than once every six months (80%). Our findings show that HAE management is improving with good access to on-demand and prophylactic treatment options. However, HAE patients still have a significant burden of disease and continued research and educational efforts are needed.
Hereditary angioedema; burden of illness; management; treatment; angioedema; complement; bradykinin; allergy; survey
Although treatment with C1 esterase inhibitor (C1-INH) concentrate is well established for hereditary angioedema (HAE) attacks in general, data that assess its efficacy for cutaneous attack treatment are sparse.
To assess efficacy of plasma-derived, nanofiltered C1-INH concentrate for cutaneous attack treatment by comparing treated attacks from the uncontrolled I.M.P.A.C.T.2 study with historical data for untreated attacks.
Cutaneous attack data from patients with HAE who were treated for cutaneous edema with 20 IU/kg body weight C1-INH concentrate in the uncontrolled I.M.P.A.C.T.2 study (38 patients) were compared with data from untreated patients from an historical data base (46 patients) and included subset analyses for facial edema (treated group, 21 patients; untreated group, 33 patients) and peripheral edema (30 patients in each group). Average attack duration (AAD) per patient was the efficacy end point used to compare treated and untreated patients. Differences were assessed with a Wilcoxon test (primary analysis) and a log-rank test; AAD per patient was analyzed descriptively and graphically with Kaplan-Meier curves.
The AAD per patient of all cutaneous attacks or facial and peripheral cutaneous attack subsets was significantly faster with C1-INH treatment than without treatment (Wilcoxon and log-rank tests, both p < 0.0001 for all comparisons). Mean AADs per patient for all, facial, and peripheral attacks were 2.04, 1.45, and 2.16 days, respectively, in the C1-INH–treated group, and were 3.74, 4.45, and 2.98 days, respectively, in the untreated group. Kaplan-Meier curves corroborated the observed group differences.
Treatment of cutaneous HAE attacks (all attacks or facial and peripheral attack subsets) with 20 IU/kg C1-INH concentrate provided faster attack resolution compared with no treatment.
C1 esterase inhibitor; C1-INH concentrate; Berinert; cutaneous edema; facial edema; peripheral edema; hereditary angioedema; HAE; angioneurotic edema; I.M.P.A.C.T.2 study.
Selective immunoglobulin E (IgE) deficiency (IgED) is defined as serum levels of IgE more than or equal to 2 kIU/L and is associated with immune dysregulation and autoimmunity. This study aimed to investigate a prevalence of atherosclerotic cardiovascular disease (ASCVD) in population with IgED. Within the electronic patient record (EPR) database of Leumit Health Care Services (LHS) in Israel, data capture was performed using IBM Cognos 10.1.1 BI Report Studio software. The case samples were drawn from the full study population (n = 18,487), having any allergy-related symptoms and/or those requesting antiallergy medications and performed serum total IgE measurement during 2012 at LHS. All subjects aged more than or equal to 40 years old, with serum total IgE less than 2 kIU/L were included in case group. Control group was randomly sampled from the remained subjects, with a case-control ratio of 10 controls for each case (1:10). The comorbid cardiovascular diseases during less than or equal to 10 years before serum total IgE testing were identified and retrieved using specific International Classification of Diseases, 9th Revision, Clinical Modification diagnostic codes. There were 103 in case and 1030 subjects in control group. Compared with control group patients, the case group had significantly more arterial hypertension [34 (37.7%) versus 187 (18.2%), p < 0.001], ischemic heart disease (IHD) [26 (25.2%) versus 87 (8.4%), p < 0.001], carotid stenosis [5 (4.9%) versus 7 (0.7%), p = 0.003], cerebrovascular disease (CVD) [3 (2.9%) versus 5 (0.5%), p = 0.029], and peripheral vascular disease (PVD) [4 (3.9%) versus 9 (0.9%), p = 0.024]. IgED is associated with higher prevalence of arterial hypertension and ASCVD.
Selective; IgE; deficiency; cardiovascular; ischemic; heart; arterial; hypertension
Recurrent episodes of flushing, urticaria, and angioedema raise suspicion for many conditions with a wide differential diagnosis. The diagnostic approach involves consideration of allergic, cardiovascular, gastrointestinal, endocrine, infectious, neurologic, dermatologic, and drug-related causes. We describe a unique case of recurrent episodes of flushing, urticaria, and angioedema that has gone into remission after a novel therapeutic intervention.
Mast cell activation disorder; mastocytosis; urticaria; angioedema; vitamin D deficiency
Exposure to indoor allergens represents a significant risk factor for allergies and asthma in several parts of the world. In Mexico, few studies have evaluated indoor allergens, including cat, dog, and mouse allergens and the factors that predict their presence. This study evaluates the main environmental and household predictors of high prenatal allergen levels and multiple allergen exposures in a birth cohort from Mexico City. A cross-sectional study was conducted as part of a birth cohort study of 1094 infants recruited during pregnancy and followed until delivery. We collected dust samples in a subset of 264 homes and assessed environmental factors. Der p 1, Der f 1, dust mite group 2, Fel d 1, Can f 1, Rat n 1, Mus m 1, and Bla g 2 concentrations in dust samples were measured using immunoassays. To define detectable allergen levels, the lowest limits of detection for each allergen were taken as cutoff points. Overall allergen exposure was considered high when four or more allergens exceeded detectable levels in the same household. Logistic regression was used for predictive models. Eighty-five percent of homes had at least one allergen in dust over the detection limit, 52.1% had high exposure (four or more allergens above detectable limits), and 11.7% of homes had detectable levels for more than eight allergens. Der p 1, Der p 2, Mus m 1, and Fel d 1 were the most frequent allergens detected. Each allergen had both common and distinct predictors. The main predictors of a high multiple allergen index were the size of the home, pesticide use, mother's age, mother as homemaker, and season. Increased indoor environmental allergen exposure is mainly related to sociodemographic factors and household cleaning.
Cat; environment; indoor exposure; Mexico; mouse