A systematic review and meta-analysis found that reactions to direct penicillin challenges in patients with penicillin allergy histories are infrequent, researchers reported today in JAMA Internal Medicine.

The review included 56 primary studies involving participants who underwent a direct penicillin challenge, which involves giving a patient with a low-risk penicillin allergy history a small oral dose of a penicillin without prior testing and then observing them for a possible reaction. The procedure is viewed as a more feasible and less costly method for confirming a penicillin allergy than skin testing, but the perceived risk of reaction remains a barrier. More than 95% of patients with a penicillin allergy label are not truly allergic.

Among the 9,225 participants in the studies, 438 experienced reactions to a direct penicillin challenge, corresponding to an overall meta-analytic frequency of 3.5% (95% credible interval [CrI], 2.5% to 4.6%), with a frequency of 2.2% (95% CrI, 1.2% to 3.2%) for children and 6.6% (95% CrI, 4.6% to 9.5%) for adults. 

A higher risk of reaction was found in studies performed in children (odds ratio [OR], 3.37; 95% CrI, 1.98 to 5.98), in outpatients (OR, 2.19; 95% CrI, 1.08 to 4.75), and those performed using a graded (OR, 3.25; 95% CrI, 1.50 to 7.06) or prolonged (OR, 5.45; 95% CrI, 2.38 to 13.28) challenge. Studies performed in North America had a lower risk of reaction (OR, 0.36; 95% CrI, 0.20 to 0.61). Only five severe reactions occurred across included studies.

Results could boost penicillin allergy delabeling

The study authors say the findings are important because patients with penicillin allergies are more likely to be treated with second-line antibiotics, which may lead to longer hospital stays and higher healthcare costs, and the use of broad-spectrum second-line agents has been associated with the development of antimicrobial resistance. They hope that more use of direct penicillin challenges could expand penicillin allergy delabeling efforts.

"Considering that up to 50% of inpatients are treated with antibiotics, it is crucial to increase penicillin allergy assessments and delabel those without the allergy to prevent the adverse outcomes associated with deferring first-line antibiotics," they wrote.

Implementation of an ambulatory antibiotic stewardship program (ASP) intervention at a network of hospitals and clinics cut unnecessary antibiotic prescribing for upper respiratory infections (URIs) by 50% without diminishing patient satisfaction, researchers reported today in Infection Control & Hospital Epidemiology.

The multifaceted ambulatory ASP intervention, implemented across Mayo Clinic facilities in Minnesota, Wisconsin, Arizona, and Florida in July 2020, aimed to reduce antibiotic use for tier 3 URI syndromes, which are defined as URIs for which antibiotics should never be prescribed. In a study published in 2023, Mayo Clinic researchers reported the intervention was associated with 48.4% relative reduction in the antibiotic prescribing rate for tier 3 URI encounters.

In this study, Mayo Clinic researchers analyzed data from patients who completed surveys with six questions assessing patient satisfaction pre- and post-implementation. Participants in both cohorts were aged 19 to 65 years, predominantly female, and had received care from either a physician or an advanced practice provider. 

No difference in patient satisfaction

Overall, a total of 75,874 tier 3 primary care encounters occurred during the pre- and post-implementation periods. Among the 2,956 survey participants (1,715 from the pre- and 1,241 from the post-implementation cohorts), tier 3 antibiotic prescribing decreased from 28.3% pre- to 14.1% post-implementation (a 50% relative reduction). 

When the researchers compared the survey responses of the pre- versus post-implementation cohorts, they found no statistically significant changes for any of the six survey questions or their associated means. For the first question ("Likelihood of you recommending our practice to others"), antibiotic prescribing was associated with statistically significant higher mean satisfaction scores in the overall and pre-implementation cohorts, but the researchers say the difference in mean score was small and may not be meaningfully different.

The researchers say that while the survey respondents represent only a small subset of the overall tier 3 encounters during the study, and the responses may skew toward patients with stronger opinions, the findings are still noteworthy.

"Programmatic efforts to reduce inappropriate antibiotic prescribing should not be dissuaded by concerns over reduced patient satisfaction, although empowering providers with tools to educate patients and provide non-antibiotic value are paramount," they concluded.

A University of Pittsburgh–led study estimates that psychiatric inpatients—especially those on the geriatric unit—with COVID-infected roommates were at much higher risk of infection than those exposed to contagious patients housed elsewhere in the unit from 2020 to 2023.

For the study, published late last week in the American Journal of Infection Control, the researchers compared the risk of SARS-CoV-2 transmission in six units of a US psychiatric hospital among patients with an infectious roommate with that of those with an infectious unit mate from July 2020 to August 2023.

The hospital placed patients with COVID-19 diagnoses in a separate unit that used negative air pressure and required staff to wear N95 respirators. Patients with known SARS-CoV-2 exposure were housed in a separate unit, and new patients were either placed in an individual room or with an unexposed roommate. In all units, physical distancing and universal masking were required until March 2023.

"Patients cared for in psychiatric facilities may have complex psychiatric diagnoses and coexisting medical conditions that are risk factors for severe SARS-CoV-2 infection and complications of infection, and may lack the ability to adhere to masking, social distancing, and other mitigation strategies," the authors noted. 

Geriatric-unit patients at 6 times the risk

The analysis included 40 and 387 roommate and unit mate exposures, respectively. The COVID-19 infection rate was 10.05% overall, 24.4% for exposed roommates, and 9.3% for exposed unit mates. Average exposure time was 1.84 days.

Cohorting contagious and exposed individuals and avoiding multi-bedded rooms may successfully mitigate COVID-19 transmission risk during psychiatric care.

Patients who shared a room with a contagious roommate were 3.14 more likely than those with an infected unit mate to test positive for COVID-19. Patients exposed to a sick roommate or unit mate in the geriatric psychiatric unit were 6.38 times more likely to become infected. Group therapy wasn't associated with viral transmission.

"Cohorting contagious and exposed individuals and avoiding multi-bedded rooms may successfully mitigate COVID-19 transmission risk during psychiatric care," the researchers wrote. "Group therapy may continue to be offered with appropriate mitigation measures due to the minimal contribution to transmission that group therapy offers."

• The US Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS) has confirmed four more H5N1 avian influenza outbreaks in diary herds, two in Texas and one each in California and Idaho. The new confirmations push the nation’s total to 207 herds from 14 states. California, the most recently affected state, now has eight outbreaks.
• The Taliban has suspended polio vaccination campaigns in Afghanistan, the Associated Press (AP) reported today, based on United Nations sources. The group relayed its decision to UN officials just before a September vaccine drive was to begin. It’s not clear why the group suspended the campaign. Afghanistan is one of two countries where wild poliovirus type 1 (WPV1) is still endemic. The country, along with neighboring Pakistan, has reported a rise in WPV1 cases this year, and Pakistan has recently reported more attacks on polio vaccination teams, some of them deadly.