APAAACI clinical pathway on direct provocation testing for penicillin allergy delabeling

Background: Allergy to penicillin is commonly reported in many countries and is an overwhelming global public health concern. Penicillin allergy labels can lead to the use of less effective antibiotics and can be associated with antimicrobial resistance. Appropriate assessment of suspected penicillin allergy (often including skin testing, followed by drug provocation testing [DPT] performed by allergists) can prevent the unnecessary restriction of penicillin or delabelling. Many countries in the Asia Pacific (AP) have very limited access to allergy services, and there are significant disparities in the methods of evaluating penicillin allergy. Therefore, a clinical pathway for the management of penicillin allergy is essential. Objectives: To develop a risk-stratified clinical pathway for delabeling penicillin allergy, taking into account the distinct epidemiology, patient/sensitization profiles, and disparities of allergy services or facilities within the AP. Methods: A risk-stratified penicillin allergy delabeling clinical pathway was formulated by the Drug Allergy Committee of the Asia Pacific Association of Allergy, Asthma and Clinical Immunology. and members of the Penicillin Allergy Disparities survey in AP each representing one country/region of the AP. The clinical pathway was tested based on a database of anonymized patients who were sequentially referred for and completed penicillin allergy evaluation in Hong Kong. Results: The clinical pathway was piloted employing a "hub-and-spoke" approach to foster multidisciplinary collaboration between allergists and nonallergists. A simulation run of the algorithm on a retrospective Hong Kong cohort of 439 patients was performed. Overall, 367 (84%) of patients were suitable for direct DPT and reduced the need for skin testing or specialist's care for 357 (97%) skin test-negative individuals. Out of the skin test-negative patients, 345 (94%) patients had a negative DPT. Conclusions: This risk-stratification strategy for direct oral DPT can reduce the need for unnecessary skin testing in patients with low-risk penicillin allergy histories. The hub and spoke model of care may be considered for further piloting and validation in other AP populations that lack adequately trained allergists.