A physician-led effort to remove penicillin allergy labels from low-risk patients at a Veterans Administration medical center removed the label in more than a third of those who were evaluated, researchers from Texas reported today in Open Forum Infectious Diseases.

Earlier studies have found that more than 95% of people reporting penicillin allergies, often labeled during childhood, are not truly allergic to penicillin and other beta-lactam antibiotics. The mislabeling or outdated labeling is a clinical problem, because patients with infections who don't have true penicillin allergies often receive antibiotics that aren't as effective, are more expensive, or are broad-spectrum antibiotics that increase the risk of Clostridium difficile and other adverse reactions.

Between November 2022 and December 2023, researchers screened 272 inpatient veterans who had penicillin allergy labels and interviewed 154 for possible delabeling. They delabeled 53 patients, 26 directly, 23 after an oral amoxicillin challenge, and 4 after outpatient allergy referral. Though the facility is large, it doesn't have onsite allergy physician coverage.

Successful results in patients with underlying comorbidities

Of the 53 patients who were delabeled, 25 later received penicillin-class prescriptions. No adverse events occurred in those who had undergone oral amoxicillin challenge. Researchers found that patients with low-risk penicillin allergy history were more likely to undergo a challenge if admitted with an infectious disease.

Only one inappropriate relabeling event occurred, which the team corrected. 

The researchers concluded that the findings demonstrate a successful provider-led system for removing penicillin allergy labels in US veterans who have complex comorbidities. "These findings add to the body of literature supporting the inpatient use of oral amoxicillin challenges by non-allergy providers as a means of expanding access to penicillin allergy evaluation," they wrote.

The United Kingdom this year is reporting its highest pertussis (whooping cough) level in decades, the country's Health Security Agency (HSA) said today. 

Monthly cases have been rising since January, with nearly 2,600 in May alone, with the year's total at nearly 7,600 cases. Though about 53% were in people ages 15 and older ,who usually experience mild disease, high numbers have also been reported in babies younger than 3 months—the group at highest risk for complications. So far, nine infant deaths have been reported since pertussis activity began rising in November 2023.

Pertussis activity is rising in the United Kingdom and other countries due to multiple factors, the HSA said. They include the cyclical nature of the disease, which peaks every 3 to 5 years, and low levels when pandemic measures were in place. The last cyclical rise occurred in 2016. A peak year is overdue, and the impact of the pandemic also means there is reduced immunity in the population, the group said.

The HSA said timely vaccination in pregnancy and childhood is crucial for protecting vulnerable infants. However, the latest update data show declining pertussis vaccination levels in pregnant women. Coverage in March 2024 was 58.9%, down from a peak of 72.6% in March 2017.