Prospective outcomes of penicillin allergy evaluation: Quality of life and relabeling rates.

BACKGROUND

Inaccurate penicillin allergy (PA) labels are associated with clinical and public health burdens. Although delabeling programs are effective, long-term data on the sustainability of delabeling and patient-centered outcomes remain limited.

OBJECTIVE

To evaluate 12-month relabeling rates, antibiotic use, and changes in health-related quality of life (HRQoL) after PA evaluation.

METHODS

HK-SPADE study was a prospective, longitudinal cohort embedded within the Hong Kong Drug Allergy Delabelling Initiative. Adults referred for suspected PA underwent standardized evaluation including skin test and drug provocation test. Patients were stratified into delabeled (negative drug provocation test result) and confirmed to have allergy groups. Incorrect relabeling, antibiotic reuse, and HRQoL using the Drug Hypersensitivity Quality-of-Life Questionnaire were assessed at 6 and 12 months.

RESULTS

Of 141 patients, 117 (83%) were delabeled and 24 (17%) were confirmed to have allergy. Among 88 delabeled patients with complete follow-up, one-third had reused penicillins but 15 (17%) were incorrectly relabeled within 12 months, despite a territory-wide unified electronic medical record system. Both delabeled and confirmed to have allergy groups demonstrated sustained improvements in Drug Hypersensitivity Quality-of-Life Questionnaire scores at 6 and 12 months (P < .001). Notably, within the confirmed to have allergy group, patients who safely reused non-penicillin antibiotics had further HRQoL improvements compared with those who did not (P = .043).

CONCLUSION

Incorrect PA relabeling persists despite integrated electronic records, highlighting factors beyond mere documentation errors. Structured PA evaluation confers durable HRQoL improvements for all patients, regardless of delabeling outcome. The findings underscore the need for reinforced educational interventions to protect delabeling success and uphold the broader therapeutic and psychological benefits of delabeling.