Objectives In high-income countries, up to 25% of inpatients have a self-reported penicillin allergy (PA). After testing, 95% of these self-reported PAs are incorrect. These incorrectly labelled PAs increase the use of broad-spectrum antibiotics, and drive bacterial resistance. The epidemiology of PA in low- and middle-income countries is unknown. We aimed to describe the epidemiology and delabelling outcomes of self-reported PA in South African (SA) inpatients. Methods We conducted point prevalence surveys between April 2019 and June 2021 at seven hospitals in Cape Town, South Africa. A team trained in the PEN-FAST allergy decision tool conducted in-person interviews, and reviewed patient notes to identify and risk stratify inpatients with a self-reported PA. These patients were referred to the Groote Schuur Hospital (GSH) allergy clinic for delabelling. Results A total of 1486 hospital inpatients were surveyed and 3.2% (n = 48) carried a PA label. Importantly, 64.6% (n = 31) were classified by PEN-FAST as low risk for true penicillin hypersensitivity. Overall, 25% of the self-reported PAs received a β-lactam antibiotic in hospital and were directly delabelled. Delabelling attrition was very high, with 6.3% (3/48) of the self-reported PAs attending the GSH allergy clinic, and only one patient proceeding to a negative oral penicillin challenge. Conclusions Inpatient self-reported PA was lower in South Africa hospitals compared with other upper-middle-income countries, and the majority of patients carried a low-risk PA label. Linkage for delabelling with the allergy clinic was very poor, and thus strategies to improve access and delivery of delabelling remains an urgent public health issue.

Background. Up to a quarter of inpatients in high-income countries (HICs) self-report beta-lactam allergy (BLA), which if incorrect,increases the use of alternative antibiotics, worsening individual health outcomes and driving bacterial resistance. In HICs, up to 95% ofself-reported BLAs are incorrect. The epidemiology of BLA in low- and middle-income African countries is unknown.Objectives. To describe the epidemiology and de-labelling outcomes of self-reported BLA in hospitalised South African (SA) patients.Methods. Point-prevalence surveys were conducted at seven hospitals (adult, paediatric, government and privately funded, district andtertiary level) in Cape Town, SA, between April 2019 and June 2021. Ward prescription records and in-person interviews were conductedto identify and risk-stratify BLA patients using the validated PEN-FAST tool. De-labelling was attempted at the tertiary allergy clinic atGroote Schuur Hospital.Results. A total of 1 486 hospital inpatients were surveyed (1 166 adults and 320 children). Only 48 patients (3.2%) self-reported a BLA,with a higher rate in private than in government-funded hospitals (6.3% v. 2.8%; p=0.014). Using the PEN-FAST tool, only 10.4% (n=5/48)of self-reported BLA patients were classified as high risk for true penicillin hypersensitivity. Antibiotics were prescribed to 70.8% (n=34/48)of self-reported BLA patients, with 64.7% (n=22/34) receiving a beta-lactam. Despite three attempts to contact patients for de-labelling atthe allergy clinic, only 3/36 underwent in vivo testing, with no positive results, and 1 patient proceeded to a negative oral challenge.Conclusion. Unlike HICs, self-reported BLA is low among inpatients in SA. The majority of those who self-reported BLA were low risk fortype 1 hypersensitivity, but outpatient de-labelling efforts were largely unsuccessful.