An Economic Evaluation of Direct Oral Penicillin Challenge for De-Labelling Low Risk Patients With a Penicillin Allergy Label.

BACKGROUND

Removing inaccurate penicillin allergy labels (PALs) can reduce unnecessary exposure to 'watch' and 'reserve' groups of antibiotics and thereby reduce antimicrobial resistance. The most efficient model for a non-allergy-specialist-led penicillin allergy de-labelling (PADL) service has not been established.

OBJECTIVE

To determine the costs to the UK National Health Service of a direct oral penicillin challenge (DPC) for low-risk patients with a PAL in three hospitals in England, each with a different non-allergy-specialist delivery model: pharmacist-led, nurse-led, and mixed multidisciplinary.

METHODS

Cost analysis of the DPC pathway, including resources related to staff time and antibiotics. The effect of de-labelling on healthcare utilisation over 5 years was modelled using data from the published literature.

RESULTS

In total, 2257 patients from the Acute Medical or Infectious Disease Unit (AMU/IDU), Pre-surgical, and Haematology-Oncology departments were screened. Subsequently, 126 underwent DPC, and 122 were de-labelled. Twenty-two of these were de-labelled in time to affect their antibiotic regimen; 6 from AMU/IDU and 16 Pre-surgery. The DPC represented 22%-23% of the pathway cost in the pharmacist-led and mixed models, and 15% in the nurse-led model. Across departments and models, the cost per de-labelled patient varied between £577 (95% Credible Interval: 370, 633) for haematology-oncology patients to £2329 (947, 19,504) for AMU/IDU patients, both under the nurse-led model. After 5 years, recouping costs was unlikely for AMU/IDU patients under any model or for all patients combined under the mixed model.

CONCLUSIONS

The penicillin allergy de-labelling pathway cost was  ≥ 4-fold that of the DPC alone. Costs were up to 3 times higher in an acute compared to an elective setting. No short-term cost savings were identified from proactive or opportunistic penicillin allergy de-labelling in this study.