Betalactam hypersensitivity: The importance of delabelling in primary care

Beta-lactam allergy in patients: an antibiotic stewardship challenge

BACKGROUND

Patients are commonly reported as being allergic to beta-lactam (BL) antibiotics. However, many patients with this reported allergy are able to receive BL treatments because they do not have true allergies. In many cases these are simply intolerances due to side effects reported as an allergy. Delabelling these patients leads to better clinical outcomes, optimal antibiotic usage, decreased bacterial resistance and reduced healthcare costs. Therefore, the aims of this study were to identify incorrectly labelled BL allergies in hospitalised patients and to assess antibiotic use in delabelled patients in order to establish a quality indicator to optimise antimicrobial treatments.

METHODS

A prospective study was conducted in which hospitalised patients treated with antimicrobial drugs and labelled as 'BL-allergic' were identified by clinical pharmacists. An allergist assessed whether patients were suitable candidates for a skin test or oral challenge. The Allergy Service removed 'BL-allergic' labels if negative results were obtained. Delabelled patients were followed up by clinical pharmacists to study the use of BL antibiotics as a result of the delabelling programme.

RESULTS

A total of 176 suspected allergic patients were identified and 91 (51.7%) were tested either by a skin test or oral challenge based on the patient indicators. Seven (16.4%) patients tested were allergic to BL antibiotics, 76 (83.5%) were totally delabelled and eight (0.1%) were partially delabelled. Thirty-two (38.1%) delabelled patients required antibiotic treatment in another inpatient or outpatient setting, of whom 27 (84.3%) patients with a new infectious episode received BL treatments while five (15.7%) continued to receive antimicrobial treatments without BL.

CONCLUSION

After the implementation of a protocol to detect incorrect BL allergy labels, 83.5% of the patients in this cohort were completely delabelled. This shows that there is a clear opportunity to optimise the use of antibiotics by delabelling 'BL-allergic' patients.

β-Lactam allergy delabeling is safe and saves costs in Primary Care

OBJECTIVE

To determine whether the β-lactam allergy delabeling was safe and cost-saving in Primary Care (PC) patients.

DESIGN

We have conducted a retrospective chart review of PC patients with β-lactam allergy label evaluated in our Allergy Unit between 2017 and 2022. SITE: Allergy Department. Hospital Virgen del Rocio (Sevilla).

PARTICIPANTS

A total of 391 patients labeled for β-lactam allergy in PC were studied.

MAIN MEASUREMENTS

(a) Outcome evaluation of a β-lactam allergy delabeling procedure. (b) A ratio between the total e-prescribed antibiotic cost and the number of treatment days (the experimental daily antibiotic cost or EDAC) before and after delabeling was analyzed in delabeled and truly allergic patients.

RESULTS

The results of skin testing were positive in 9.2% of the reported cases (36 of 391 patients). The reactions to oral provocation challenge (OPC) occurred in 2.14% of the patients who underwent negative skin testing to offending β-lactam (in 15 of 699 OPC). A total of 307 patients (78.5%) were delabeled; 70 (17.9%) had a β-lactam selective response and 14 (3.59%) reacted to both penicillin and cephalosporin. The EDAC before and after the procedure in delabeled patients was significantly lower (0.88 € vs 0.62 €, p<10-3), than that observed in truly allergic group (0.87 € vs. 0.76 €, p=not significant).

CONCLUSION

To delabel β-lactam allergy in Primary Care patients is safe in most patients, cost-saving in antibioticotherapy, and allows identify the main clinical β-lactam allergy phenotypes that benefit from this procedure.