Skin testing, computerized support tool may help confirm penicillin allergy in hospital inpatients
Researchers at Massachusetts General Hospital (MGH) in Boston have developed skin testing and computerized support tools that can aid in confirming whether or not a recorded penicillin and cephalosporin allergy in hospital inpatients is real, researchers report online in the Journal of Allergy and Clinical Immunology (Feb. 27, 2017).
“From 10 to 15 per cent of hospitalized patients have penicillin allergy in their medical record, but studies have shown that more than 95 per cent are not really allergic,” said Dr. Kimberly Blumenthal, co-lead and corresponding author of the paper, who was quoted in a press release.
“We know that over-reporting of penicillin allergies has a negative impact on patient care, as the alternative drugs often used are less effective, more toxic and can both leave patients vulnerable to dangerous C. difficile infection and increase antibiotic resistance in the community. The need to address over-reported penicillin allergy has been widely acknowledged, but how to do that has remained unclear,” said Dr. Blumenthal, of the Division of Rheumatology, Allergy, and Immunology, the Medical Practice Evaluation Center, and the Lawrence Center for Quality and Safety at MGH.
Skin testing, computerized support tool
In the report, the researchers describe how both tested protocols, the use of penicillin allergy skin tests and a computerized guideline/decision support tool, safely increased the use of penicillin and penicillin-derived antibiotics in patients.
“This study offered a unique opportunity to examine what strategy best serves inpatients who have this listed allergy,” said co-lead author Dr. Paige Wickner, instructor in medicine, and director of the Allergy Training Program at Brigham Health and Women’s Hospital in Boston.
During a two-year period from June 2014 to June 2016, the researchers compared three different approaches to treating inpatients who needed antibiotic treatment and had a recorded penicillin allergy.
The first five months consisted of standard care treatment, in which patients received testing via either skin test or test dosing.
During the next seven months, inpatients with a penicillin allergy who needed antibiotic treatment were screened for skin-test eligibility. According to the researchers, patients with a history of more serious allergic reactions or those taking therapies that could interfere with skin testing were ineligible, and testing also required the consent of the patient and the care team. Patients whose skin test was negative and who safely tolerated an oral dose of amoxicillin were determined not to be allergic.
During the following seven-month period, physicians used a computerized treatment guideline and decision support tool to categorize a reaction based on details in regards to the reported allergic reaction. The reactions were categorized as follows:
Very low risk: full dose of penicillin or cephalosporin
Low risk: reduced test dose of penicillin or cephalosporin
Medium/high risk: consult with allergy specialist
Serious reaction: avoid penicillin or cephalosporin
Findings revealed that due to logistical issues, only 43 out of the 179 patients eligible for skin testing actually received the test. But while that did not result in a significant increase between the standard-of-care and skin-test periods in the overall percentage of those receiving penicillin or cephalosporin, among patients who had the test, the likelihood of receiving the more favourable prescription increased almost six times.
Data also showed that none of the skin-tested patients proved to have a penicillin allergy, and they also had more than double the chance of being discharged with a penicillin or cephalosporin prescription.
“We found that addressing penicillin allergy by either method could lead to an overall improvement in antibiotic choice for these patients,” said Dr. Blumenthal.
“We don’t want to discourage any method of evaluation because even thinking about whether a patient’s penicillin allergy is true could lead a provider to make a different management decision. Even here at MGH, we estimated that skin testing all patients with recorded penicillin allergy would be impractical without a significant staff increase or technological guidance.”