Síguenos en Twitter     Síguenos en Facebook     Síguenos en YouTube     Siguenos en Linkedin     Correo Salutsantjoan     Gmail     Dropbox     Instagram     Google Drive     StumbleUpon     StumbleUpon     StumbleUpon     StumbleUpon     StumbleUpon     StumbleUpon     StumbleUpon


My photo
FACP. Colegio de médicos de Tarragona Nº 4305520 / fgcapriles@gmail.com




Tuesday, September 13, 2016

Penicillin Allergy

NU-EM Blog - September 12, 2016 - By Andrew Moore A - Edited by: Rusinak T -  Expert Commentary: Allen K>
Citation: [Peer-Reviewed, Web Publication] Moore A, Rusinak T (2016, September 13). The Penicillin Allergy Conundrum [NUEM Blog. Expert Commentary By Allen K]. Retrieved from http://www.nuemblog.com/blog/penicillin-allergy/
"Prevalence of Penicillin Allergy
Penicillin allergy is the most commonly reported allergy in the United States with a prevalence of up to 12.8% of the population. While this may seem inconsequential, recent data suggest patients with reported penicillin allergies have increased hospital length of stay and increased risks of clostridium difficile, vancomycin resistant enterococcus, and MRSA infections. This leads back to our original question, “Are you really allergic to penicillin?”
We know that of patients who report a penicillin allergy, 90% are able to tolerate penicillin. Using these numbers we can extrapolate that only 1/100 patients have a true allergy to penicillin. Furthermore, cross-allergenicity rates are much less common than originally thought. More recent studies demonstrate cephalosporin-penicillin cross-allergenicity rates between 0.1% and 2%, carbapenem-penicillin cross-allergenicity rates less than 1% and aztreonam-penicillin cross-allergenicity rates 0%.
Emergency Department Approach to Patients with a Self-Reported Penicillin Allergy
In most settings a good clinical history of allergy symptoms can appropriately guide antibiotic choice. When obtaining a history, it is important to ask about a patient’s previous reaction to penicillin. A rash is usually IgG mediated and not concerning while hives, angioedema or anaphylaxis are consistent with a true IgE mediated allergy. It is also useful to know if the patient had to previously seek emergency department care for an allergy as this indicates a more serious reaction. Lastly, asking the patient what antibiotics they tolerated in the past (i.e amoxicillin or other beta-lactams) may help you assess for true penicillin allergy. If it is deemed that a patient has an allergy description that is not consistent with an IgE mediated allergy, it is likely safe to attempt use of another beta-lactam such as a cephalosporin. For patients deemed unsafe to attempt alternative beta-lactam treatment, start a non-beta-lactam and refer for allergy testing. In one prevalence study, only 6% of patients reporting penicillin allergy were referred for allergy testing. If the patient is being admitted to the hospital, consider inpatient testing for IgE mediated hypersensitivity as this has been shown to decrease both inpatient complications and cost of care."