Alergia a penicilina y utilidad de las desensibilizaciones para el manejo de pacientes alérgicos dentro del programa de optimización de antibióticos

Abstract

The main objective of this thesis is to evaluate the efficacy and safety of antibiotic desensitization as a management tool for patients with antibiotic allergies. This thesis, presented as a compendium of publications, comprises three studies: The first evaluates antibiotic desensitization as a useful tool within Antimicrobial Stewardship Programs (ASP). It includes a systematic literature review and a retrospective study conducted at Hospital del Mar (Barcelona). In the review of 22 studies involving 202 cases, 97% of desensitizations were successful and well tolerated. In the clinical study, 16 desensitizations were performed in 14 patients, with 87.5% completed successfully and without severe reactions. The second publication presents a retrospective case-control study comparing clinical outcomes in penicillin-allergy-labeled (PAL) patients treated with beta-lactam desensitization versus those treated with alternative antibiotics. A total of 56 patients were included (14 desensitized and 42 controls) between 2015 and 2022. Despite having higher comorbidity and more infections caused by multidrug-resistant pathogens, desensitized patients showed no worse clinical outcomes and experienced fewer antibiotic-related adverse events. Moreover, no new resistant strains were selected in this group. The third study analyzes the cost-effectiveness of beta-lactam desensitization in hospitalized PAL patients. Using an economic model based on data from the second study, the analysis showed that although the procedure incurred higher costs (an average increase of ?37,805 per patient), it improved cure rates and survival, gaining 1.42 additional life years per patient. Desensitization was found to be cost-effective in 100% of simulations under a ?30,000 per life-year gained threshold. Beta-lactam desensitization is a safe, effective, and cost-effective strategy in patients with confirmed or high-risk penicillin allergy, with no association to worse clinical outcomes. Its integration into ASPs should be considered alongside other diagnostic tools, although further studies with larger sample sizes are needed to strengthen the evidence.

Date of Award	9 Jan 2026
Original language	Spanish
Awarding Institution	Universitat Autònoma de Barcelona (UAB)
Supervisor	Silvia Inés Gómez-Zorrilla Martín (Director) & Santiago Grau Cerrato (Director)