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A Randomized Trial Comparing Direct Challenges to Penicillin Skin Testing for Outpatient Low-Risk Penicillin Allergy
Sara Patrawala1, S Shahzad Mustafa1, Richard Kraude2
1Rochester Regional Health, Rochester, NY; Division of Allergy/Immunology/Rheumatology, Department of Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY.
Insights
Direct challenge (DC) is a safe and efficient method for penicillin allergy de-labeling in low-risk pregnant patients. This approach avoids skin testing, saving time without compromising safety during pregnancy.
Area of Science:
- Obstetrics and Gynecology
- Clinical Immunology
- Pharmacology
Background:
- Penicillin allergy de-labeling is crucial in the general population.
- Its importance is amplified in pregnancy, as penicillin is a first-line antibiotic for infections near delivery, including Group B Streptococcus.
Purpose of the Study:
- To assess the safety of a two-step direct challenge (DC) to amoxicillin without prior skin testing.
- This evaluation is for pregnant patients with a low-risk penicillin allergy label, irrespective of trimester.
Main Methods:
- A prospective, randomized controlled trial was conducted.
- Compared penicillin skin testing (PST) followed by oral amoxicillin challenge versus a two-step DC.
- Participants were pregnant women with low-risk penicillin allergy labels.
Main Results:
- 144 women were enrolled; 73 in PST and 70 in DC groups.
- 100% of DC patients had negative penicillin allergy evaluations versus 93.2% in PST.
- No reactions in either group necessitated medical treatment or epinephrine.
- Direct challenge was significantly faster than PST.
Conclusions:
- A direct challenge (DC) is as safe as penicillin skin testing (PST) for evaluating penicillin allergy in low-risk pregnant patients.
- DC offers a more time-efficient alternative for penicillin allergy assessment in pregnancy.
Background:
The importance of penicillin allergy de-labeling in the general population is well known. Its significance is further highlighted in pregnancy because penicillin-based antibiotics are first-line therapy for most infections at the time of delivery, particularly group B Streptococcus.
Objective:
To evaluate the safety of a two-step direct challenge (DC) to amoxicillin without preceding skin testing in pregnant patients with a low-risk penicillin allergy label, regardless of trimester.
Methods:
We performed a prospective, randomized controlled trial comparing penicillin skin testing (PST) followed by an oral amoxicillin challenge versus a two-step DC to amoxicillin without preceding skin testing in pregnant patients regardless of trimester with a low-risk penicillin allergy label.
Results:
A total of 144 women were included in this study, 73 of whom underwent PST and 70 of whom underwent DC. Of those women, 68 (93.2%) undergoing PST had a negative evaluation for penicillin allergy compared with 70 (100%) who underwent DC. No reactions in either PST or DC groups required medical treatment or, notably, administration of epinephrine. Direct challenge took significantly less time compared with PST. Median time for PST was 75 minutes (interquartile range, 75-80 minutes) compared with 65 minutes (interquartile range, 65-70 minutes) for DCs.
Conclusion:
For evaluation of penicillin allergy in pregnancy, we demonstrate that a DC is as safe as PST in low-risk pregnant patients.
