Reported PCN Allergy Doesn’t Mean Real PCN Allergy

September 1, 2017

Spoon Feed
All children in the PED who were low risk for penicillin allergy on this questionnaire were confirmed to have no true penicillin allergy with skin testing followed by oral challenge.  Forbes wrote an interesting post on this article.

Why does this matter?
There are certain conditions in which a penicillin is the best antibiotic choice (streptococcal pharyngitis, syphilis, etc).  This is hampered when a patient reports an allergy to penicillin.  Most of the time, the reported allergy to penicillin does not equal actual allergy to penicillin.  This study suggests a questionnaire with low risk responses for penicillin allergy may allow it to be administered safely.

Clever study
Parents filled out an online questionnaire about reported penicillin allergy in their child.  I contacted the lead author to try to get a copy of the questionnaire, but he said they have not published it and have modified it for the next phase of this project…mysterious.  Wish I knew exactly what questions they asked, because it is hard to use these study results without knowing that.  One hundred children with low-risk responses were skin tested for penicillin allergy, and none were found to have true allergy. Low-risk features included rash (macular, papular, or hives), itching, diarrhea, vomiting, runny nose, nausea, cough, or reported family history. High-risk features included wheezing, difficulty breathing, airway swelling, syncope, or hypotension. 

Source
Allergy Testing in Children With Low-Risk Penicillin Allergy Symptoms.  Pediatrics. 2017 Jul 3. pii: e20170471. doi: 10.1542/peds.2017-0471. [Epub ahead of print]

Peer reviewed by Thomas Davis, MD.