RESUMEN
BACKGROUND: The link between immediate hypersensitivity reactions (HSR) following the first cetuximab infusion and the IgE sensitization against anti-galactose-α-1,3-galactose (α-Gal) is now well-established. An automated Fluoroenzyme-Immunoassay (FEIA) is available and may facilitate the screening of patients with anti-α-Gal IgE before treatment. METHODS: This study aimed to evaluate its performances as compared to a previously validated anti-cetuximab IgE ELISA, using 185 samples from two previously studied cohorts. RESULTS: Despite 21.1% of discrepancies between the two techniques, FEIA discriminated better positive patients and similarly negative ones with a ≥ 0.525 kUA/L threshold. Sensitivity was 87.5% for both tests, specificity was better for FEIA (96.3% vs ELISA: 82.1%). FEIA had a higher positive likelihood ratio (23.9 vs ELISA: 4.89) and a similar negative likelihood ratio (0.13 vs ELISA: 0.15). In our population, the risk of severe HSR following a positive test was higher with FEIA (56.7% vs ELISA: 19.6%) and similar following a negative test (0.7% vs ELISA: 0.8%). CONCLUSION: Although the predictive value of the IgE screening before cetuximab infusion remains discussed, this automated commercial test can identify high-risk patients and is suitable for routine use in laboratories. It could help avoiding cetuximab-induced HSR by a systematic anti-α-Gal IgE screening before treatment.
Asunto(s)
Anafilaxia , Hipersensibilidad a los Alimentos , Humanos , Anafilaxia/inducido químicamente , Anafilaxia/diagnóstico , Cetuximab/efectos adversos , Hipersensibilidad a los Alimentos/diagnóstico , Galactosa/efectos adversos , Inmunoglobulina E/efectos adversos , Ensayo de Inmunoadsorción EnzimáticaRESUMEN
BACKGROUND: Alpha-gal syndrome (AGS) is an IgE-mediated allergy to galactose-alpha-1,3-galactose. Clinical presentation ranges from hives to anaphylaxis; episodes typically occur 2-6 h after exposure to alpha-gal-containing products. In the United States, lone star tick bites are associated with the development of AGS. To characterize features of AGS, we evaluated a cohort of patients presenting for care at the University of North Carolina, focusing on symptoms, severity, and identifying features unique to specific alpha-gal-containing product exposures. METHODS: We performed a chart review and descriptive analysis of 100 randomly selected patients with AGS during 2010-2019. RESULTS: Median age at onset was 53 years, 56% were female, 95% reported White race, 86% reported a history of tick bite, and 75% met the criteria for anaphylaxis based on the involvement of ≥2 organ systems. Those reporting dairy reactions were significantly less likely to report isolated mucocutaneous symptoms (3% vs. 24%; ratio [95% CI]: 0.1 [0.1, 0.3]) than those who tolerated dairy, and were more likely to report gastrointestinal symptoms (79% vs. 59%; ratio [95% CI]: 1.3 [0.7, 2.6]), although this difference was not statistically significant. Dairy-tolerant patients demonstrated higher alpha-gal sIgE titers (as a percentage of total IgE) than dairy-reactive patients (GM 4.1 [95% CI: 2.7, 6.1] vs. GM 2.5 [95% CI: 1.3, 4.8], respectively; ratio -1.6 [95% CI: -1.0, 3.9]). CONCLUSION: While tick exposure is common in the southern United States, nearly all AGS patients reported a tick bite. Gastrointestinal symptoms were prominent among those reporting reactions to dairy. Anaphylaxis was common, underscoring the severity and need to raise awareness of AGS among patients and providers.
Asunto(s)
Anafilaxia , Hipersensibilidad a los Alimentos , Mordeduras de Garrapatas , Humanos , Femenino , Masculino , Anafilaxia/diagnóstico , Anafilaxia/epidemiología , Anafilaxia/etiología , Mordeduras de Garrapatas/complicaciones , Galactosa , Alérgenos , Inmunoglobulina E , Hipersensibilidad a los Alimentos/diagnóstico , Hipersensibilidad a los Alimentos/epidemiología , Hipersensibilidad a los Alimentos/complicacionesRESUMEN
BACKGROUND: IgE to galactose alpha-1,3 galactose (alpha-gal) causes alpha-gal syndrome (delayed anaphylaxis after ingestion of mammalian meat). Development of sensitization has been attributed to tick bites; however, the possible role of other parasites has not been well studied. OBJECTIVE: Our aims were to assess the presence, relative abundances, and site of localization of alpha-gal-containing proteins in common ectoparasites and endoparasites endemic in an area of high prevalence of alpha-gal syndrome, as well as to investigate the ability of ascaris antigens to elicit a reaction in a humanized rat basophil in vitro sensitization model. METHODS: Levels of total IgE, Ascaris-specific IgE, and alpha-gal IgE were measured in sera from patients with challenge-proven alpha-gal syndrome and from controls without allergy. The presence, concentration, and localization of alpha-gal in parasites were assessed by ELISA, Western blotting, and immunohistochemistry. The ability of Ascaris lumbricoides antigen to elicit IgE-dependent reactivity was demonstrated by using the RS-ATL8 basophil reporter system. RESULTS: Alpha-gal IgE level correlated with A lumbricoides-specific IgE level. Alpha-gal protein at 70 to 130 kDa was detected in A lumbricoides at concentrations higher than those found in Rhipicephalus evertsi and Amblyomma hebraeum ticks. Immunohistochemistry was used to localize alpha-gal in tick salivary acini and the helminth gut. Non-alpha-gal-containing A lumbricoides antigens activated RS-ATL8 basophils primed with serum from subjects with alpha-gal syndrome. CONCLUSION: We demonstrated the presence, relative abundances, and site of localization of alpha-gal-containing proteins in parasites. The activation of RS-ATL8 IgE reporter cells primed with serum from subjects with alpha-gal syndrome on exposure to non-alpha-gal-containing A lumbricoides proteins indicates a possible role of exposure to A lumbricoides in alpha-gal sensitization and clinical reactivity.
Asunto(s)
Ascaris lumbricoides/inmunología , Hipersensibilidad a los Alimentos/etiología , Garrapatas/inmunología , Animales , Antígenos Helmínticos/inmunología , Células Cultivadas , Disacáridos/análisis , Humanos , Inmunoglobulina E/inmunología , RatasAsunto(s)
Anafilaxia/inducido químicamente , Antineoplásicos Inmunológicos/efectos adversos , Cetuximab/efectos adversos , Disacáridos/inmunología , Hipersensibilidad a las Drogas/etiología , Inmunoglobulina E/sangre , Sustitutos del Plasma/efectos adversos , Poligelina/efectos adversos , Adulto , Anafilaxia/sangre , Anafilaxia/diagnóstico , Anafilaxia/inmunología , Biomarcadores/sangre , Hipersensibilidad a las Drogas/sangre , Hipersensibilidad a las Drogas/diagnóstico , Hipersensibilidad a las Drogas/inmunología , Epítopos , Humanos , Masculino , Factores de RiesgoRESUMEN
Objective: Transcatheter aortic valve implantation (TAVI) is rapidly replacing cardiac surgery due to its minimal invasiveness and practicality. Midterm immunological studies on the biocompatibility of galactose-alpha-1,3-galactose (α-Gal)-carrying bioprosthetic heart valves for TAVI are not available. In this study we investigated whether bioprosthetic heart valves employed for TAVI augment an α-Gal-specific antibody-dependent and antibody-independent immune response 3 months after TAVI implantation. Methods: This prospective observational study included 27 patients with severe aortic valve stenosis undergoing TAVI and 10 patients with severe mitral valve regurgitation treated with a transcatheter MitraClip (Abbott Laboratories, Abbott Park, Ill) procedure. Blood samples were drawn before and 90 days after treatment at a routine checkup. Serum samples were analyzed using enzyme-linked immunosorbent assay. Serum concentrations of α-Gal-specific immunoglobulin (Ig) G, IgG subclasses and IgE, complement factor 3a, NETosis-specific citrullinated H3, and the systemic inflammation markers soluble suppression of tumorigenicity and interleukin 33 were evaluated. Results: Three months after TAVI, we found significantly increased serum concentrations of α-Gal-specific IgG3, complement factor complement factor 3a, citrullinated H3 levels, and soluble suppression of tumorigenicity (P = .002, P = .001, P = .025, and P = .039, respectively). Sensitization of α-Gal-specific IgE antibodies occurred in 55% of all patients after TAVI. Conclusions: Our results indicate that TAVI elicits a midterm, specific humoral immune response against α-Gal and causes an unspecific humoral inflammation compared with patients undergoing MitraClip implantation. This observation will lead to a better understanding of postintervention morbidity and the long-term durability of bioprostheses and indicates that caution is appropriate when designing implantation strategies for younger patients.
RESUMEN
The heterogeneity of glycosylation on therapeutic monoclonal antibodies (mAbs) may affect the safety and efficacy of these agents. In particular, glycans of nonhuman origin, such as galactose-alpha-1,3-galactose (gal-α-gal) and N-glycolylneuraminic acid (NGNA), in the Fc region of therapeutic mAbs produced from murine cell lines carry a risk of immunogenicity. Immunogenic glycan structures can have immune-mediated clearance, resulting in faster clearance from in vivo circulation than non-immunogenic structures. To demonstrate the impact of these Fc nonhuman glycans on in vivo clearance, we purified and analyzed the glycan profile of a monoclonal antibody (mAb1) from human serum samples collected from clinical study participants. We purified mAb1 in a three-step chromatographic separation process (protein A, immobilized anti-mAb1 antibody affinity, and weak cation exchange chromatography) and extracted and labeled its N-linked oligosaccharide structures with 2-aminobenzamide acid for analysis on ultrahigh-performance hydrophilic interaction liquid chromatography. A comparison of the glycan profile of mAb1 recovered from human serum on the same day and 4 weeks after dosing revealed no significant differences, indicating similar clearance of mAb1 with nonhuman gal-α-gal or NGNA glycan in the Fc region compared with the human glycans. The relative proportions of the glycans remained similar, and all patients who had already received multiple doses of mAb1 over the course of a year were negative for antidrug antibodies, suggesting that none of the glycans induced an immune response. Therefore, we concluded that mAb1 gal-α-gal and NGNA glycoforms represent a low risk of conferring immunogenicity.
Asunto(s)
Anticuerpos Monoclonales/química , Fragmentos Fc de Inmunoglobulinas/química , Inmunoglobulina G/química , Polisacáridos/química , Animales , Anticuerpos Monoclonales/inmunología , Línea Celular , Glicosilación , Humanos , Fragmentos Fc de Inmunoglobulinas/inmunología , Inmunoglobulina G/inmunología , Ratones , Polisacáridos/inmunología , Isoformas de Proteínas/química , Isoformas de Proteínas/inmunologíaRESUMEN
Snake antivenom is the only specific treatment for snakebite envenoming, but life-threatening anaphylaxis is a severe side effect and drawback for the use of these typically mammalian serum products. The present study investigates the hypotheses whether serum IgE antibodies against the epitope galactose-alpha-1,3-galactose (α-gal) located on the heavy chain of non-primate mammalian antibodies are a possible cause for hypersensitivity reactions to snake antivenom. Serum samples from 55 patients with snakebite envenoming were obtained before administration of snake antivenom and tested for serum IgE (sIgE) against α-gal and total IgE. Early anaphylactic reactions (EARs) during the first 3 h after antivenom administration were classified into mild, moderate or severe and correlated with the presence of sIgE against α-gal. Fifteen (27%) out of 55 patients (37 male, 18 female, median 34 years, range 9-90 years) developed EARs after antivenom administration. Eleven, three and one patients had mild, moderate and severe EARs, respectively. Serum IgE against α-gal was detected in 17 patients (31%); in five (33%) out of 15 patients with EARs and in 12 (30%) out of 40 patients without EAR (Odds Ratio = 1.2; 95%-confidence interval: 0.3-4.2) with no correlation to severity. Although the prevalence of serum IgE against α-gal was high in the study population, very high levels of total IgE in the majority of patients question their clinical relevance and rather indicate unspecific sIgE binding instead of allergy. Lack of correlation between α-gal sIgE and EARs together with significantly increased total IgE levels suggest that sIgE against α-gal is not the major trigger for hypersensitivity reactions against snake antivenom.
RESUMEN
BACKGROUND: The galactose-α1,3-galactose (α-Gal) syndrome (AGS) is a novel form of food allergy. Patients experience delayed severe allergic reactions after mammalian meat consumption due to IgE antibodies directed against the carbohydrate α-Gal present in mammalian meat. The onset of the disease is associated with tick bites. OBJECTIVE: To characterize a cohort of patients with AGS from Sweden on a clinical and serological level, and identify risk factors for disease severity. METHODS: A total of 128 patients with symptoms after mammalian meat intake and IgE to α-Gal were included. Medical examination and diagnosis were made by an allergologist and questionnaires were filled in regarding onset of symptoms, tick exposure, and airborne allergies. Serum IgE reactivity against multiple food and airborne allergens, as well as protein extract from the tick Ixodes ricinus, was measured using ImmunoCAP. RESULTS: The majority of patients were middle aged, with equal gender distribution. Nearly all reported symptoms more than 2 hours after meat consumption. Urticaria (90%) and gastrointestinal symptoms (74%) were most common. Almost half of the patients suffered from anaphylaxis, and α-Gal IgE levels were significantly higher among these patients compared with those without anaphylaxis. Nearly all patients had been tick bitten and 75% had IgE against I. ricinus. More than half of the patients with AGS were atopic, and atopy increased the risk of anaphylaxis with pulmonary manifestations. Only 2 patients belonged to blood group B/AB. CONCLUSION: AGS is an upcoming food allergy where patients report severe symptoms and tick bites. Atopy was found to affect the manifestation of the disease in Swedish patients.
Asunto(s)
Hipersensibilidad a los Alimentos , Mordeduras de Garrapatas , Alérgenos , Animales , Hipersensibilidad a los Alimentos/diagnóstico , Hipersensibilidad a los Alimentos/epidemiología , Galactosa , Humanos , Inmunoglobulina E , Persona de Mediana Edad , Suecia/epidemiología , Mordeduras de Garrapatas/epidemiologíaRESUMEN
A anafilaxia idiopática não apresenta etiologia conhecida. A sua prevalência é estimada entre 10-35% de todas as modalidades de anafilaxia. A sintomatologia apresentada é a mesma de qualquer outra anafilaxia: urticária, angioedema, ruborização, prurido, hipotensão arterial, taquicardia, manifestações gastrointestinais (disfagia, náusea, vômitos, cólicas abdominais, diarreia), asma, edema laríngeo, tontura e síncope. A mortalidade é rara. Não há transmissão genética, mas 40% dos pacientes são atópicos. É mais frequente nos adultos do que nas crianças, e principalmente em mulheres. É um diagnóstico de exclusão. Ocorre ativação mastocitária com desgranulação citoplasmática dos mediadores de anafilaxia (triptase, histamina, entre outros). É uma anafilaxia com boa resposta aos corticoides, e, portanto, caso não haja resposta adequada a doses eficazes de prednisona/prednisolona, o seu diagnóstico deve ser revisto. O diagnóstico diferencial da anafilaxia idiopática inclui: a mastocitose sistêmica indolente, síndromes de ativação mastocitária monoclonais, alergia à galactose-alfa-1,3 galactose, anafilaxia induzida por exercícios (com e sem dependência alimentar e medicamentosa), angioedema hereditário (congênito e adquirido), feocromocitoma, síndrome carcinoide, anafilaxia oral acarina, alergia ao Anisakis simplex, disfunção das cordas vocais, síndrome escombroide, alergia ao sêmen, alergia ao látex, manifestações psicossomáticas (síndrome do pânico, globus hystericus e a síndrome de Münchausen), bem como as tradicionais e mais frequentes modalidades de anafilaxia (alergia a alimentos, medicamentos e insetos). O tratamento na crise aguda da anafilaxia idiopática é o mesmo do que nas demais anafilaxias, incluindo a administração intramuscular imediata de epinefrina. Deve haver uma generosa e prolongada prescrição de corticoterapia oral, e também a instituição de medicação preventiva (anti-histamínicos anti- H1 e anti-H2, cetotifeno, albuterol oral, montelucaste, cromoglicato de sódio, e por último o omalizumabe). Os pacientes devem portar epinefrina autoinjetora e ser instruídos sobre como agir em caso de um episódio anafilático. Eles respondem bem à administração de epinefrina. A corticoterapia oral, por 4-6 semanas, pode induzir uma remissão completa.
Idiopathic anaphylaxis is a condition of unknown etiology. Its prevalence ranges from 10 to 35% of all cases of anaphylaxis. Clinical symptoms and signs are those of classic anaphylaxis, including urticaria, angioedema, flushing, itching, hypotension, tachycardia, gastrointestinal manifestations (dysphagia, nausea, vomiting, abdominal cramps, and diarrhea), asthma, laryngeal edema, dizziness, and syncope. Mortality is rare. There is no genetic transmission, but about 40% of patients are atopic. It is more common in adults than in children, affecting mainly women. It is considered a diagnosis of exclusion of other known forms of anaphylaxis. Mast cell activation occurs with cytoplasmatic degranulation of mediators of anaphylaxis (tryptase and histamine, among others). Because idiopathic anaphylaxis is a steroid-responsive condition, if it is not controlled with adequate doses of prednisone/prednisolone, the diagnosis should be challenged. The differential diagnosis of idiopathic anaphylaxis includes indolent systemic mastocytosis, clonal mast cell activation syndromes, galactose-alpha-1,3- galactose allergy, exercise-induced anaphylaxis (both food- and drug-dependent and -independent), hereditary angioedema (congenital and acquired), pheochromocytoma, carcinoid syndrome, oral mite anaphylaxis, Anisakis simplex allergy, vocal cord dysfunction, scombroid poisoning, semen allergy, latex allergy, psychosomatic conditions (panic attacks, globus hystericus, and Münchausen syndrome), and the classic forms of anaphylaxis (food, drug, and insect allergies). Treatment of acute idiopathic anaphylaxis is the same as in the other forms of anaphylaxis, including intramuscular epinephrine, but with prolonged oral corticosteroid therapy. It might also include other oral preventive medications (H1 and H2 antihistamines, ketotifen, oral albuterol, montelukast, sodium cromoglycate, and recently omalizumab). Patients should have an epinephrine auto-injector and be instructed on self-management of anaphylaxis. Good response to epinephrine is observed, and oral corticosteroid therapy for 4-6 weeks can induce complete remission.
Asunto(s)
Humanos , Prednisolona , Prednisona , Trastornos de Deglución , Epinefrina , Trastorno de Pánico , Anisakis , Corticoesteroides/uso terapéutico , Hipersensibilidad al Látex , Mastocitosis Sistémica , Albuterol , Angioedemas Hereditarios , Omalizumab , Hipersensibilidad a los Alimentos , Globo Faríngeo , Síndrome de Activación de Mastocitos , Antagonistas de los Receptores Histamínicos , Anafilaxia , Síndrome de Munchausen , Pánico , Pacientes , Asma , Signos y Síntomas , Síndrome , Terapéutica , Corticoesteroides , Diagnóstico , Diagnóstico DiferencialAsunto(s)
Enfermedad de la Arteria Coronaria/etiología , Enfermedad de la Arteria Coronaria/inmunología , Hipersensibilidad a los Alimentos/complicaciones , Hipersensibilidad a los Alimentos/inmunología , Inmunoglobulina E/inmunología , Animales , Humanos , Carne/efectos adversos , Modelos Cardiovasculares , Modelos Inmunológicos , Mordeduras de Garrapatas/complicaciones , Mordeduras de Garrapatas/inmunologíaRESUMEN
INTRODUCTION:: Decellularization of thick tissue is challenging and varying. Therefore, we tried to establish a multifactorial approach for reliable aortic wall decellularization. METHODS:: Porcine aortic walls were decellularized according to different procedures. Decellularization was performed for 24 (G1), 48 (G2), and 72 h (G3) with a solution of 0.5% desoxycholate and 0.5% dodecyl sulfate. The procedure was characterized using intermittent washing steps, the inclusion of sonication as well as DNase and α-galactosidase treatment. The decellularization efficiency was measured by the evaluation of 4',6-diamidino-2-phenylindole and hematoxylin and eosin staining and quantitative DNA assays. Pentachrome and picrosirius red staining, scanning electron microscopy as well as glycosaminoglycan assays were performed to evaluate the effect of the procedure on the extracellular matrix. RESULTS:: 4',6-Diamidino-2-phenylindole and hematoxylin and eosin staining revealed a large amount of remaining nuclei in all groups. However, consecutive DNase treatment had a significant effect. While the remaining DNA was detected in some samples of G1 and G2, samples of G3 were fully decellularized. Glycosaminoglycan content was significantly reduced to 50% after 24 h (G1) but remained constant for G2 and G3. Picrosirius red staining revealed an intact and stable collagen network without any visible defects. Pentachrome staining substantiated these results. Nonetheless, the fiber network remains intact, which could be confirmed by reflection electron microscopy analysis. CONCLUSION:: In this study, we developed a procedure that grants successful decellularization of porcine aortic wall while maintaining the fibrous microstructure. We highlighted the significant effect of DNase and α-galactosidase treatment. In addition, we could show the need for a multifactorial treatment and comprehensive evaluation protocols for thick tissue decellularization.
Asunto(s)
Aorta/citología , Aorta/efectos de los fármacos , Matriz Extracelular/efectos de los fármacos , Ingeniería de Tejidos/métodos , Animales , Aorta/metabolismo , Ácido Desoxicólico/farmacología , Desoxirribonucleasas/farmacología , Matriz Extracelular/metabolismo , Matriz Extracelular/patología , Glicosaminoglicanos/metabolismo , Dodecil Sulfato de Sodio/farmacología , Sonicación , Porcinos , Técnicas de Cultivo de Tejidos , Andamios del Tejido , alfa-Galactosidasa/farmacologíaRESUMEN
BACKGROUND: Galactose-alpha-1,3-galactose (alpha-gal) syndrome is characterized by the presence of serum specific IgE antibodies to alpha-gal and delayed type I allergic reactions to the carbohydrate alpha-gal after consumption of mammalian (red) meat products and drugs of mammalian origin. Diagnostics currently rely on patient history, skin tests, determination of serum specific IgE antibodies, and oral food or drug challenges. OBJECTIVE: We sought to assess the utility of different basophil parameters (basophil reactivity and sensitivity, the ratio of the percentage of CD63+ basophils induced by the alpha-gal-containing allergen to the percentage of CD63+ basophils after stimulation with anti-FcεRI antibody [%CD63+/anti-FcεRI], and area under the dose-response curve [AUC]) as biomarkers for the clinical outcome of patients with alpha-gal syndrome compared with subjects with asymptomatic alpha-gal sensitization. METHODS: In addition to routine diagnostics, a basophil activation test (Flow CAST) with different concentrations of alpha-gal-containing allergens (eg, commercially available alpha-gal-carrying proteins and pork kidney extracts) was performed in 21 patients with alpha-gal syndrome, 12 alpha-gal-sensitized subjects, and 18 control subjects. RESULTS: Alpha-gal-containing allergens induced strong basophil activation in a dose-dependent manner in patients. Basophil reactivity at distinct allergen concentrations, the %CD63+/anti-FcεRI ratio across most allergen concentrations, the AUC of dose-response curves, and basophil allergen threshold sensitivity (CD-sens) with pork kidney extract were significantly higher in patients with alpha-gal syndrome compared with those in sensitized subjects. All parameters were negative in control subjects. CONCLUSION: The basophil activation test should be considered as an additional diagnostic test before performing time-consuming and potentially risky oral provocation tests. The %CD63+/anti-FcεRI ratio for all allergens and AUCs for pork kidney were the best parameters for distinguishing patients with alpha-gal syndrome from subjects with asymptomatic alpha-gal sensitization.
Asunto(s)
Anafilaxia , Basófilos/inmunología , Galactosa/efectos adversos , Inmunoglobulina E/inmunología , Adulto , Anafilaxia/diagnóstico , Anafilaxia/inmunología , Anafilaxia/patología , Basófilos/patología , Femenino , Galactosa/inmunología , Humanos , Masculino , Persona de Mediana Edad , Pruebas Cutáneas , SíndromeRESUMEN
Tick-induced mammalian meat allergy has become an emergent allergy world-wide after van Nunen et al. first described the association between tick bites and the development of mammalian meat allergy in 2007. Cases of mammalian meat allergy have now been reported on all 6 continents where humans are bitten by ticks, in 17 countries - Australia, United States of America (USA), Europe (France, Spain, Germany, Belgium, Switzerland, Sweden, United Kingdom, Italy, and Norway), Asia (Korea and Japan), Central America (Panama), South America (Brazil), and Africa (South Africa and Ivory Coast). To date, in each of these countries, bites from only a single tick species have been linked to the development of mammalian meat allergy: Ixodes holocyclus (Australia), Amblyomma americanum (USA), Ixodes ricinus (Europe), and Ixodes cajennense (Panama) are confirmed as culprits, and Ixodes nipponensis (Japan and Korea), Amblyomma sculptum (Brazil), Amblyomma variegatum (Ivory Coast), and Haemaphysalis longicornis (Japan) suspected of provoking mammalian meat allergy after tick bite. Other tick species remain to be formally identified (South Africa). Identification of tick species associated with development of mammalian meat allergy is crucial to the uptake of public health measures to prevent tick bites from culprit tick species, for both individuals living in these tick-endemic areas and those who choose to visit these regions. We report a tick associated with the enhancement of mammalian meat anaphylaxis after tick bite which is novel for both Australia and the world and establishes Ixodes (Endopalpiger) australiensis as a second tick species associated with mammalian meat allergy in Australia.
RESUMEN
BACKGROUND: Severe meat allergy with anaphylaxis may be caused by sensitization to alpha-gal. Levels of alpha-gal sensitization that correlate with high risk of meat allergy are currently unknown. We have identified an area with a high prevalence of reported red meat allergy which offered the opportunity to evaluate the diagnostic value of IgE antibody tests. METHODS: To determine levels of alpha-gal IgE and alpha-gal:total IgE ratio in a large cohort of subjects with challenge-proven meat allergy compared with control subjects from the same environment, we conducted fieldwork assessing 131 participants who reported adverse reactions to meat, and 26 control subjects, by questionnaires, IgE sensitization to alpha-gal and oral food challenge to beef sausage. RESULTS: Eighty-four participants were diagnosed with alpha-gal allergy. Alpha-gal IgE ranged between 0.7 and 344.5 kU/L. Alpha-gal:total IgE ratio ranged from 0.1% to 67.6%. Logistic regression analysis showed both alpha-gal IgE and alpha-gal:total IgE ratio strongly correlated with meat allergy, with AUC of 0.95. The values giving the best correct classification were IgE of 2.00 kU/L and ratio of 0.75%. The value above which there is a 95% probability of meat allergy is IgE>5.5 kU/L and ratio of 2.12%. CONCLUSION: Alpha-gal allergy in a population with a high prevalence of reported red meat allergy showed a more rapid onset of symptoms than previously described and a high prevalence of isolated subjective gastrointestinal manifestations. Cutoff values are described for levels of sensitization to alpha-gal IgE and alpha-gal:total IgE ratio that are highly likely to result in clinically significant meat allergy.
Asunto(s)
Disacáridos/inmunología , Hipersensibilidad a los Alimentos/diagnóstico , Inmunoglobulina E/sangre , Carne/efectos adversos , Adolescente , Adulto , Anciano , Alérgenos/inmunología , Niño , Estudios Transversales , Femenino , Humanos , Pruebas Inmunológicas/métodos , Masculino , Persona de Mediana Edad , Fenotipo , Prevalencia , Sensibilidad y Especificidad , Encuestas y Cuestionarios , Adulto JovenRESUMEN
Tick-induced mammalian meat allergy has become an emergent allergy world-wide after van Nunen et al. first described the association between tick bites and the development of mammalian meat allergy in 2007. Cases of mammalian meat allergy have now been reported on all 6 continents where humans are bitten by ticks, in 17 countries
Asunto(s)
Humanos , África , Américas , Anafilaxia , Asia , Australia , Bélgica , América Central , Europa (Continente) , Alemania , Reino Unido , Hipersensibilidad , Italia , Ixodes , Carne , Salud Pública , América del Sur , España , Suecia , Suiza , Mordeduras de Garrapatas , Garrapatas , Estados UnidosRESUMEN
SUMMARY: Food allergies, especially delayed hypersensitivity reactions, are often challenging for both patients and clinicians. Here, we report the case of a 64-year-old man who had allergic reactions six hours after eating a meal containing red meat. He reported that he had several tick bites in months before the reaction. High serum specific IgE levels of alpha-gal confirmed the diagnosis of alpha-gal allergic reaction with delayed onset after red meat ingestion caused by tick bite.
Asunto(s)
Hipersensibilidad a los Alimentos/inmunología , Hipersensibilidad Tardía/inmunología , Carne Roja/efectos adversos , Mordeduras de Garrapatas/inmunología , Hipersensibilidad a los Alimentos/sangre , Hipersensibilidad a los Alimentos/diagnóstico , Galactosa/análogos & derivados , Galactosa/inmunología , Humanos , Hipersensibilidad Tardía/sangre , Hipersensibilidad Tardía/diagnóstico , Inmunoglobulina E/sangre , Inmunoglobulina E/inmunología , Pruebas Intradérmicas , Masculino , Persona de Mediana Edad , Noruega , Mordeduras de Garrapatas/complicaciones , Mordeduras de Garrapatas/diagnóstico , Factores de TiempoRESUMEN
Eosinophilic esophagitis (EoE) is an antigen/allergy-mediated chronic inflammatory condition. The rapid rise in the number of cases of EoE suggests an as-yet undiscovered environmental trigger. This study tested the hypothesis that immunoglobulin E (IgE) to galactose-alpha-1,3-galactose (alpha-gal), a newly recognized sensitization induced by a tick bite that causes mammalian meat allergy, is a risk factor for EoE. We conducted a case-control study using prospectively collected and stored samples in the University of North Carolina EoE Patient Registry and Biobank. Serum from 50 subjects with a new diagnosis of EoE and 50 non-EoE subjects (either with gastroesophageal reflux disease or dysphagia from non-EoE etiologies) was tested for alpha-gal-specific IgE using an ImmunoCAP-based method. Specific IgE > 0.35 kUA /L was considered a positive result. Subjects with EoE were a mean of 35 years old, 68% were male, and 94% were white. Non-EoE controls were a mean of 42 years, 50% were male, and 78% were white. A total of 22 (22%) subjects overall had alpha-gal-specific IgE > 0.35 kUA /L. Of the EoE cases, 12 (24%) were positive, and of the non-EoE controls, 10 (20%) were positive (p=0.63). Neither the proportion sensitized nor the absolute values differed between EoE and non-EoE subjects. We found a similar but high rate of alpha-gal sensitization in patients with EoE as found in non-EoE controls who were undergoing endoscopy. While our data do not support alpha-gal sensitization as a risk factor for EoE, the high rates of sensitization observed in patients undergoing upper endoscopy for symptoms of esophageal dysfunction is a new finding.
Asunto(s)
Disacáridos/inmunología , Esofagitis Eosinofílica/inmunología , Inmunoglobulina E/inmunología , Adulto , Biopsia , Estudios de Casos y Controles , Trastornos de Deglución/inmunología , Trastornos de Deglución/patología , Endoscopía del Sistema Digestivo , Esofagitis Eosinofílica/patología , Femenino , Hipersensibilidad a los Alimentos/inmunología , Reflujo Gastroesofágico/inmunología , Reflujo Gastroesofágico/patología , Humanos , Masculino , Carne , Persona de Mediana EdadRESUMEN
We report the case of a 55-year-old man who went into anaphylactic shock six hours after eating a meal containing meat. He reported having had several tick bites in months before the reaction. The serum specific IgE showed strong positivity to alpha-gal. This is clearly alpha-gal anaphylaxis with delayed onset after meat ingestion caused by tick bite, confirmed by alpha-gal IgE positivity.
Asunto(s)
Anafilaxia/etiología , Disacáridos/inmunología , Hipersensibilidad a los Alimentos/inmunología , Carne/efectos adversos , Mordeduras de Garrapatas/inmunología , Humanos , Inmunoglobulina E/sangre , Masculino , Persona de Mediana Edad , Mordeduras de Garrapatas/complicacionesRESUMEN
Anaphylaxis is a severe allergic reaction that can be rapidly progressing and fatal, and therefore establishing its cause is pivotal to long-term risk management. Our recent work has identified a novel IgE antibody response to a mammalian oligosaccharide epitope, galactose-alpha-1,3-galactose (alpha-gal). IgE to alpha-gal has been associated with 2 distinct forms of anaphylaxis: (1) immediate-onset anaphylaxis during first exposure to intravenous cetuximab and (2) delayed-onset anaphylaxis 3 to 6 hours after ingestion of mammalian food products (eg, beef and pork). Results of our studies and those of others strongly suggest that tick bites are a cause, if not the only significant cause, of IgE antibody responses to alpha-gal in the southern, eastern, and central United States; Europe; Australia; and parts of Asia. Typical immune responses to carbohydrates are considered to be T-cell independent, whereas IgE antibody production is thought to involve sequential class-switching that requires input from T cells. Therefore, establishing the mechanism of the specific IgE antibody response to alpha-gal will be an important aspect to address as this area of research continues.