Penicillin Allergy Labeling Common in Pediatric Populations

Margaret G. Taylor, MD

A new cohort study determined that penicillin allergy labeling (PAL) in children was common across a variety of clinical practices, with roughly half of all participants in the study being labeled after receiving 1 or no penicillin prescriptions.

Penicillin allergy labels factor into clinical decision-making, especially considering that penicillin allergy is the most common drug allergy in the world affecting approximately 5-10% of the global population.

Despite this, most children who are labeled allergic do not have 1 hypersensitivity allergic reactions and instead have a history of predictable adverse reactions or unspecified illness symptoms after receiving penicillin.

In the hospital setting, children with unconfirmed PALs have prolonged hospital stays, higher rates of adverse events, and more infections due to Clostridium difficile and vancomycin-resistant Enterococcus compared with children without PALs

Furthermore, studies describing penicillin allergy labeling are not in abundance.

As such, Margaret G. Taylor, MD, Department of Pediatrics at Baylor College of Medicine, Texas Children’s Hospital, Houston, and fellow investigators set out to describe the epidemiology and other factors associated with penicillin allergy labels in 2 large US pediatric primary care networks.

The Methods

The longitudinal birth cohort study was conducted in 90 primary care pediatric practices across the US including Houston, Texas, Austin, Texas, Philadelphia, Pennsylvania, and various centers in New Jersey.

Children were included in the birth cohort if they were born between January 1, 2020, and June 30, 2020 , were seen in-person or via telehealth with Texas Children’s Pediatrics or Children’s Hospital of Philadelphia within their first 14 days of life, and completed at least 2 additional primary care provider visits in the first year.

The primary outcome was addition of a PAL in the electronic health record, defined as an allergy label to a penicillin derivative (including penicillin, ampicillin, amoxicillin, piperacillin-tazobactam, amoxicillin-clavulanate, ampicillin-sulbactam, or antistaphylococcal penicillin).

Children with isolated cephalosporin or carbapenem allergies were not included in the PAL group.

The Findings

A total of 334,465 children were included in the birthcohort, 164,173 of whome were female. Regarding race and ethnicity, 72,831 (21.8%) were Hispanic, 59,598 (17.8%) were non-Hispanic Black, and 148,534 (44.4%) were non-Hispanic White.

Investigators observed that 18 015 (5.4%) children were labeled as penicillin allergic, yet the prevalence of penicillin allergy labeling ranged from 0.9% to 10.2% across practices.

Children were labeled at a median (IQR) age of 1.3 (0.9-2.3) years, with Non-Hispanic White children more likely to be labeled compared with non-Hispanic Black children after controlling for potential confounders (adjusted odds ratio, 1.7 [95% CI, 1.6-1.8]).

A total of 6797 allergic children (37.7%) were labeled after receiving 1 penicillin prescription, and 1423 (7.9%) were labeled after receiving 0 penicillin prescriptions.

In their concluding remarks, investigators referenced previous studies that have shown less than 5% of children labeled as penicillin allergic had a type 1 hypersensitivity allergy on skin testing or oral challenge.

When applying that data to the current cohort, they hypothesized that more than 16000 children in the Houston and Philadelphia regions likely have inaccurate penicillin allergy labels.

“Therefore, quality improvement efforts to address unconfirmed penicillin allergy labels should engage directly with PCPs, who are most likely to interact with children outside of an acute illness and identify ways to prevent redocumenting PALs in children who have been cleared of their label,” the team wrote.

The study, "Factors Associated With Penicillin Allergy Labels in Electronic Health Records of Children in 2 Large US Pediatric Primary Care Networks," was published online in JAMA Open Network.