IgE antibodies to alpha-gal in foresters and forest workers from La Rioja, North of Spain
Venturini M1, Lobera T1, Sebastián A2, Portillo A3, Oteo JA3
1Allergy Department, Centro de Alta Resolución San Millán, Logroño (La Rioja), Spain
2Neumology Department, Hospital Clínico Universitario Lozano Blesa, Zaragoza, Spain
3Center of Rickettsioses and Artropod-Borne Diseases, Hospital San Pedro-CIBIR, Logroño (La Rioja), Spain
J Investig Allergol Clin Immunol 2018; Vol. 28(2)
Objetive: To investigate the prevalence and associated factors to the presence of alpha-gal-specific IgE in a risk group of foresters and forest workers from La Rioja and in a control group.
Methods: A total of 169 workers and 100 individuals who did not recall tick-bites were selected. A questionnaire including demographic data and number of tick bites per year was administered by a physician. Alpha-gal sIgE was assessed with serum samples that had been taken in 2010 using ImmunoCAP®.
In 2015, second serum specimens were taken from all the workers but one who had positive specific IgE to alpha-gal in 2010. These new samples were tested for IgE to the alfa-gal epitope and to mammalian meat.
Results: The prevalence of positive sIgE to alpha-gal in the risk population was 15% vs. 4% in the control population. Alpha-gal sIgE positivity was associated with the number of tick bites per year and with the seniority in the workplace. Thirteen out of 21 patients sensitized to alpha-gal in 2010 showed positive specific IgE to alpha-gal with serum samples from 2015. Eleven of them had specific IgE to mammalian meat but none reported symptoms of meat allergy.
Conclusion: The prevalence of alpha-gal sIgE antibodies in this Spanish risk population was higher than in the control group and it was associated with the number of tick-bites per year and with the seniority in the workplace. None of worker sensitized to mammalian meat developed meat allergy, possibly due to the discrete levels of sIgE to alpha-gal.
Key words: Allergens and epitopes, IgE, anaphylaxis, tick bites, Alpha-gal