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Improving routine prenatal penicillin allergy testing for reported penicillin allergy
Margaret M Gill1, Sara Gasner2, Alisha Banken2
1Family Medicine, Mayo Clinic, Rochester, Minnesota, USA gill.margaret@mayo.edu.
Insights
Penicillin allergy testing in pregnant patients is safe and effective for de-labeling true allergies. This allows for appropriate antibiotic use during labor, improving outcomes for both mother and baby.
Area of Science:
- Clinical Medicine
- Allergy and Immunology
- Obstetrics and Gynecology
Background:
- Self-reported antibiotic allergies are linked to increased healthcare costs, more resistant infections, and poorer health outcomes.
- Less than 5% of patients with reported penicillin allergies have a clinically significant reaction upon testing.
- Penicillin is the recommended treatment for Group B Streptococcus (GBS) in pregnant patients, necessitating allergy evaluation.
Purpose of the Study:
- To assess the safety and feasibility of penicillin allergy testing in pregnant patients.
- To evaluate the impact of allergy de-labeling on subsequent antimicrobial therapy.
- To improve guideline-adherent treatment for GBS colonization in pregnant individuals.
Main Methods:
- A quality improvement project utilized an algorithm for patient selection for penicillin allergy testing.
- Testing involved skin prick tests (benzylpenicilloyl polylysine, penicillin G potassium, amoxicillin, penicilloate), intradermal tests, and oral challenges.
- Patient outcomes were analyzed to determine the intervention's effectiveness.
Main Results:
- Of 1266 pregnant patients, 236 (19%) reported penicillin allergy; 212 were eligible for testing.
- 101 patients completed testing, with 7 (7%) testing positive and 94 (93%) testing negative and being de-labeled.
- 17 de-labeled patients with GBS colonization received intrapartum penicillin without adverse events.
Conclusions:
- Penicillin allergy testing is a safe and feasible approach for pregnant patients reporting allergies.
- Allergy de-labeling enables safe, guideline-recommended antimicrobial use during labor and delivery.
- Further research is needed on cost-effectiveness and long-term impact on care episodes.
Background:
Patients with self-reported antibiotic allergies have a higher cost of care, more frequent infections with resistant bacteria and worse health outcomes than patients without antibiotic allergies. Ultimately, less than 5% of patients who report a penicillin allergy have a clinically significant immune-mediated hypersensitivity reaction when tested. As 10%-30% of the population of pregnant patients are colonised for group B Streptococcus (GBS) and guidelines recommend penicillin as the treatment of choice for GBS, current recommendations support penicillin allergy testing in pregnant patients who report an allergy.
Methods And Intervention:
In this quality improvement project, nursing staff used an algorithm outlining inclusion and exclusion criteria to determine which patients were eligible to have penicillin allergy testing completed. Penicillin allergy testing consisted of a skin test using benzylpenicilloyl polylysine (Pre-Pen), penicillin G potassium, amoxicillin and alkaline hydrolysis mix (penicilloate) as a prick skin test, followed by intradermal skin test and finally an oral challenge with either amoxicillin or penicillin. Patient outcomes were analysed to evaluate the impact of the intervention.
Results:
Of the 1266 patients receiving prenatal care during the intervention, 236 (19%) reported a history of penicillin allergy, and 212 if these were eligible for testing. 150 of the eligible patients were offered penicillin allergy testing. 101 patients (67%) completed testing and 49 (33%) declined testing. Seven patients (7%) had positive penicillin allergy testing, while 94 patients (93%) had negative penicillin allergy testing and were immediately de-labelled as penicillin allergic. Seventeen of the de-labelled patients subsequently tested positive for GBS colonisation, and all received intrapartum penicillin without adverse events.
Conclusions:
Pursuing penicillin allergy testing for pregnant patients with reported penicillin allergy is a safe and feasible approach, allowing for allergy de-labelling and safe, guideline-driven antimicrobial therapy during subsequent labour and delivery hospitalisations. Cost-effectiveness of the allergy testing and impact on later episodes of care should be further investigated.
