Alergia a betalactámicos a partir de los 60 años

Abstract

ABSTRACT Background: People who thought to have an allergy to betalactams may tolerate the drugs in subsequent exposures due to initial false labeling of allergies, the spontaneous loss of sensitivity to BLs over time or age-related decline in sensitization. As a result, they may be treated with less appropriate antibiotics, causing more side effects and entailing increased costs for health systems. The goals of this investigation were: Estimate the real prevalence of betalactam allergy in patients over 60 years, previously labeled as allergic to BLs; determine if those patients with a confirmed diagnosis in the past were able to tolerate BLs at the present time; and demonstrate cost reduction in antibiotic treatment after underestimating the diagnosis of betalactam allergy in patients >80 years admitted to the hospital. Patients and methods: Patients allergic to BLs were divided into group A (aged 60–79 years) and B (aged ≥80 years). Clinical history, skin testing, drug challenge tests (DCT) and restesting were used to classify participants as allergic with immediate reactions, nonimmediate reactions, or not allergic. We compared clinical entities, drugs involved, and final outcome by age group. The average cost of non-betalactam antibiotics for patients older than 80 years who required them during hospital admission was calculated and compared with the average cost of treating the same disease with BLs antibiotics. Results: Of 1362 cases evaluated, 565 underwent an allergological study. The skin was the most common organ involved. Anaphylaxis, positive DCT and side chain reactions were more frequent in group A (p<0.01). Classical benzylpenicillin determinants (benzylpenicilloyl and/or minor determinant mixture) were more frequent triggers in group B (p< 0.01). Resensitization occurred in very few participants. 83.6% of patients older than 80 years admitted to the General University Hospital of Alicante required antibiotics during hospital admission and the cost of prescribed antibiotics (non-betalactams) was higher. Conclusion: The risk for allergy to BLs decreases with age and a history of anaphylaxis by BLs is a predictor of positive results in skin tests. Both immunoglobin E (IgE) and T-cell–mediated responses can disappear in elderly people, who can develop tolerance to these antibiotics. These results are of clinical relevance to patients who need to be treated with antibiotics from this family. The cost of prescribed antibiotics for patients with BLs allergy was higher.