(269) Safety, acceptability, and effectiveness of penicillin allergy testing in pregnancy: a systematic review

Thursday, January 30, 2025

10:30 AM – 12:30 PM

Submitting Author(s)

Lindsay Reddeman, MD, MSc

Resident Physician
University of Toronto
Toronto, ON, Canada

Coauthor(s)

JL

Justin Lim, MD

University of Toronto
Toronto, Ontario, Canada
KM

Kellie Murphy, MD, MSc

University of Toronto
Toronto, Ontario, Canada
DF

David Fahmy, MD

McMaster University
Hamilton, Ontario, Canada
CW

Chris Walsh

Mount Sinai Hospital Sidney Liswood Health Sciences Library
Toronto, Ontario, Canada

Presenting Author(s)

Kristin Harris, MD

Maternal Fetal Medicine Specialist
Mount Sinai Hospital/University of Toronto
Toronto, ON, Canada

Objective: An estimated 8-13% of pregnant patients report penicillin allergy (PA). Penicillins and other beta-lactams are widely used in pregnancy but often avoided in these patients, resulting in suboptimal therapy, antimicrobial resistance, higher costs, and increased morbidity and mortality for patients and neonates. True penicillin allergy is rare and 95% of patients undergoing penicillin allergy evaluation (PAE) are delabelled. Although PAE is safe and recommended for pregnant patients, few are assessed. Recently, research concerning antenatal PAE has accelerated. We undertook a systematic review to summarize this growing body of evidence.

Study Design: A comprehensive search was conducted in collaboration with a medical information specialist, with no restriction on study language, date, or design. All peer-reviewed studies of pregnant people reporting unverified PA undergoing PAE with ≥5 participants were included. Title/abstract review, full text review, and data extraction were completed independently by 2 authors. Conflicts were resolved by a third author. Studies were evaluated using validated quality assessment tools.

Results: Seventeen studies (N=1720) were eligible for inclusion. In total 1639 (95.3%) patients were delabelled through various approaches: direct oral challenge (12.8%), penicillin skin test (PST) and oral challenge (56.5%), PST and intravenous challenge (6.0%), PST alone (22.9%), and history review (1.8%). Acceptance of PAE among patients was 68.9%. Overall, 8 mild allergy-related adverse reactions and 5 mild delayed allergy-related adverse reactions occurred, requiring minimal intervention. There were 2 severe allergy-related adverse reactions which were managed with intramuscular epinephrine; no hospital transfers were required. No adverse antenatal events were recorded.

Conclusion: PAE in pregnancy is safe, acceptable, and effective, and the case for expanding access is strong. To our knowledge, this is the first systematic review to report on antenatal PAE acceptability and effectiveness; it builds on prior safety data drawn largely from low-quality and non-peer-reviewed evidence.