Allergological Study of 565 Elderly Patients Previously Labeled as Allergic to Penicillins

Abstract

Purpose

Elderly people thought to have an allergy to beta-lactams (BLs) 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 aim of this investigation was to assess whether patients in the third and fourth age with previously confirmed allergies to BLs had lost sensitization and could tolerate these antibiotics.

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 evaluation of resensitization were used to classify participants as showing immediate reactions, non-immediate reactions, or tolerance. We compared clinical entities, drugs involved, and final outcome by age group.

Results

Of 1362 cases evaluated, 565 underwent an allergological study. The skin was the most common organ involved. Anaphylaxis and side chain reactions were more frequent in group A (p<0.01), as were positive DCT. Classical benzylpenicillin determinants (benzylpenicilloyl and/or minor determinant mixture) were more frequent triggers in group B (p< 0.01). Resensitization after challenge occurred in very few participants.

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 (ST). 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.

Keywords:

• drug allergy
• beta-lactams
• cephalosporins
• cross-reactivity
• aging
• immunosenescence
• diagnosis

Acknowledgments

The authors would like to thank Ms Meggan Harris and Dr Alexis Lara Rivero for the English edition of the manuscript.

Disclosure

Prof. Dr Javier Fernandez-Sanchez reports a grant from Carlos III Institute: RD16/06/032, during the conduct of the study. The authors report no other conflicts of interest in this work.