Testing for penicillin allergy can allow considerable savings, of 282 euros per patient hospitalized in Portuguese hospitals and up to 2103 euros in an outpatient setting. Considering conservative estimates, this would imply an estimated saving of 8.4 million euros per year in the context of hospitalization alone.

The conclusions of the economic assessment study carried out by researchers from the Faculty of Medicine of the University of Porto (FMUP), namely from MEDCIDS – Department of Community Medicine, Health Information and Decision, and from CINTESIS argues in favor of the widespread performance of tests on patients labeled as allergic to penicillins, a class that includes antibiotics in common use, such as amoxicillin.

The scientists calculated the costs, simulating and comparing two different strategies. In the first scenario, the patients were subjected to diagnostic tests for penicillin allergy and only those who tested positive were treated as allergic. In the second scenario, the patients were not subjected to this type of tests and were treated as allergic, that is, they did not receive penicillins, but alternative antibiotics.

The expenses considered in the study were those concerning the tests, the hospitalizations, or those relating to trips to the hospital and antibiotics used, which tend to be more expensive in patients labeled as allergic to penicillins.

According to Bernardo Sousa Pinto, first author of the study published in the journal Clinical Infectious Diseases, conducting penicillin allergy tests is effectively associated with fewer costs than not performing allergy tests.

“The ‘allergy’ label is also associated with increased risk of infections”

A study carried our previously, also with Bernardo Sousa Pinto as the first author, has already shown that a correct diagnosis of allergy to penicillins would allow a decrease of 3,863 hospitalization days.

Although 5% to 10% of patients say they are allergic to penicillins, specific tests allow this label to be removed in 90% of the cases, allowing treatment with cheaper antibiotics, but also more appropriate and with better clinical results.

In fact, as the authors point out, “not only economic results are at stake, but also clinical results since the penicillin allergy label is associated with an increased risk of healthcare-associated infections”.

The team, coordinated by João Fonseca, had the participation of Ana Margarida Pereira, Luís Filipe Azevedo, Luís Delgado (FMUP) and researchers of the Massachusetts General Hospital, the Harvard Medical School and the San Diego Medical Center, in the United States of America.