Galactose-α-1,3-galactose (alpha-gal) allergy: first pediatric case in a series of patients in Spain.

INTRODUCTION AND OBJECTIVES: Allergy to galactose-α-1,3-galactose (alpha-gal) is a peculiar form of food allergy generally manifesting as an anaphylactic reaction hours after mammalian meat consumption, due to the presence of specific IgE against this oligosaccharide. In addition, immediate anaphylaxis may develop after exposure to other sources of alpha-gal, such as monoclonal antibody cetuximab, vaccines, plasma expanders or anti-snake venoms. Sensitization to alpha-gal has also been implicated in the rapid degeneration of biological valve implants, and recognized as a cause of occupational disease in cattle raisers. The implication of tick bites in this type of sensitization has been accepted by all the research groups dedicated to this disease. PATIENTS AND METHOD: The present study describes the clinical and sensitization characteristics of 39 patients diagnosed with alpha-gal allergy in the hospitals of our province (Lugo, Monforte de Lemos and Burela, Spain). RESULTS: Most patients were middle-age males. Of note, is the fact that the series includes the first pediatric patient reported in Spain to date. The predominant clinical manifestations were urticaria or delayed anaphylaxis after consumption of mammalian meat. Seventy-four percent of the patients reported having suffered a previous tick bite, and the clinical presentation of anaphylaxis was significantly more prevalent in those with a persistent local reaction following the bite than in those with no such reaction (p = 0.032). CONCLUSIONS: A review is also made of the disorder which, due to its variable clinical expression, is referred to as alpha-gal syndrome. The study concludes that a diagnosis of alpha-gal allergy should be considered in patients with urticaria-anaphylaxis of uncertain origin or manifesting after the administration of vaccines or products of bovine/porcine origin.

IgE-Mediated Sensitization to Galactose-α-1,3- Galactose (α-Gal) in Urticaria and Anaphylaxis in Spain: Geographical Variations and Risk Factors.

BACKGROUND: The objectives of this study were to investigate the prevalence of sIgE to galactose-α-1,3-galactose (α-gal) in individuals with acute urticaria or anaphylaxis from different geographical areas of Spain and to evaluate the relevance of demographics and lifestyle as risk factors for this immune response. METHODS: Participants were recruited from allergy departments at 14 Spanish hospitals. Patients aged 18 years or older presenting with urticaria or anaphylaxis were enrolled into one of 2 arms: cases and controls. An interviewer-administered questionnaire collecting demographic data, lifestyle habits, and the presence of cofactors was obtained from each participant. sIgE to α-gal and total IgE were determined using ImmunoCAP. sIgE levels ≥0.35 kU/L were considered a positive result. RESULTS: The study population comprised 160 cases and 126 controls. The median age was 44 years. The overall prevalence of a positive result of sIgE to α-gal was 15.7%; this was higher in cases (26.3%) than in controls (2.4%). The sIgE anti-α-gal positivity rate ranged from 37.68% (rural) to 15.38% (semiurban), and 7.85% (urban). The rates of positivity were 46.32%, (Northern), 0.72% (Center), and 0% (Mediterranean). A positive result for sIgE to α-gal was associated with a history of tick bites, participation in outdoor activities, pet ownership, and ingestion of mammalian meats or innards before the onset of symptoms. Only alcohol consumption could be implicated as a cofactor. CONCLUSION: Sensitization to α-gal in patients with urticaria or anaphylaxis differs considerably between the 3 geographical areas studied and is related to tick bites.

Double (honeybee and wasp) immunoglobulin E reactivity in patients allergic to Hymenoptera venom: the role of cross-reactive carbohydrates and alcohol consumption.

BACKGROUND: Immunoglobulin (Ig) E-mediated sensitization to N-glycans (cross-reactive carbohydrate determinants, CCDs) may induce double IgE reactivity to honeybee venom (HBV) and yellow jacket venom (YJV) in patients who are monosensitized to either of these venoms. Alcohol consumption is associated with increased IgE levels and possibly with sensitization to CCDs in the general population. OBJECTIVES: This study investigated the factors associated with double (HBV and YJV) IgE reactivity in patients who are allergic to Hymenoptera venom, and in particular, alcohol consumption. METHODS: Ninety-one patients with Hymenoptera allergy (68 to HBV, 19 to YJV, and 4 to both venoms) were studied. Determinations included a multiallergen IgE test and IgE to HBV, YJV, natural (glycosylated) HBV phospholipase-A2 (nPLA2), recombinant (nonglycosylated) HBV phospholipase-A2 (rPLA2), MUXF (the N-glycan from bromelain), natural (glycosylated) rubber latex, total IgE. Double reactivity was defined as an IgE level > 0.35 kU(A)/L to HBV and YJV. RESULTS: Double reactivity was observed in 28/87 (32%) clinically monosensitized patients. Double reactivity was associated with high levels of total IgE, MUXF-specific IgE, nPLA2-specific IgE, latex-specific IgE, and false-positive results in the multiallergen IgE test, but not with rPLA2-specific IgE. Alcohol consumption was associated with double reactivity and with high levels of IgE to glycosylated allergens after adjusting for confounders in the multivariate analysis. CONCLUSIONS: Sensitization to CCDs and clinically irrelevant double (honeybee and wasp) IgE reactivity are common among Hymenoptera venom-allergic patients who drink alcohol. A simple questionnaire about alcohol consumption could be useful when interpreting levels of specific IgE in these patients.

House dust mite species and allergen levels in Galicia, Spain: a cross-sectional, multicenter, comparative study.

BACKGROUND AND OBJECTIVES: Mites are important sources of allergens in Galicia, Spain. The objective of this study were to identify the main mite species and to determine allergen levels in mattresses from different locations in Galicia. MATERIAL AND METHODS: Dust samples were collected with a portable vacuum cleaner for 2 minutes from 2 m2 of the surface of the mattress used by mite allergic patients and controls. After collection, samples were immediatel frozen. Mite species were collected, identified, and counted, and the results expressed as mites per gram of dust. Mite allergen levels (Der p 1 and Der f 1) were measured using monoclonal antibodies. All individuals answered a questionnaire about the characteristics of their homes. RESULTS: A total of 332 dust samples were collected (112 from mite allergic patients and 220 from controls). Thirty-two species were identified. The mean age +/-SD of all the participants was 32.4 +/- 20.8 years and of the mattresses 7.6 +/- 5.9 years. The geometric mean of the total mite counts was 910.2 mites per gram (896.2 mites per gram in the mattresses of mite allergic patients and 917.3 in the mattresses of control subjects; P > .05). The main species was Dermatophagoides pteronyssinus, which was present in 97.6% of the samples (geometric mean, 584.7 mites per gram). The geometric mean level of Der p 1 was 13.1 microg/g of dust: 11.9 in the mattresses of mite allergic patients and 13.8 in the mattresses of control subjects. The geometric mean level of Der f1 was 1.1 microg/g: 1.5 in the mattresses of mite allergic patients and 0.8 in the mattresses of control subjects. Environmental risk factors associated with high mite counts included obvious signs of humidity in the bedroom and the age of the mattress. CONCLUSIONS: The mite fauna in Galicia is comprised of many species, several of which are known to be of allergologic importance. The total population is exposed to very high levels of mite allergens.