Penicillin allergy—getting the label right
BMJ 2017; 358 doi: https://doi.org/10.1136/bmj.j3402 (Published 04 August 2017) Cite this as: BMJ 2017;358:j3402
All rapid responses
Thank you for your comments on the image of skin patch testing used to illustrate a recent article on penicillin allergy in The BMJ (BMJ 2017; 358 doi:https://doi.org/10.1136/bmj.j3402).
The article published in The BMJ is an edited version of that published in Drug and Therapeutics Bulletin doi:10.1136/dtb.2017.3.0463 (http://dtb.bmj.com/content/55/3/33)
In the longer version of this article, the section on 'Skin testing' included the following discussion of skin patch testing:
"Skin tests for non-immediate reactions are not standardised, but typically either patch tests or late reading of intradermal tests at intervals up to 72 hours are used for T-cell mediated reactions.[1] Patch tests are likely to be safe and helpful in people with other severe cutaneous reactions, but the safety of intradermal testing is uncertain and should only be considered in selected cases after careful risk assessment.[1]"
Reference
1 Mirakian R, et al. Management of allergy to penicillins and other beta-lactams. Clin Exp Allergy 2015; 45: 300–27
Competing interests: No competing interests
Please note that in addition to an inappropriate image of patch testing for penicillin allergy noted in another rapid response, the other image of some droppers failed in 'getting the label right' as it contained Penicillium which is a skin test solution for moulds, not a drug!
A picture tells a thousand words so improved accuracy in future allergy articles would be appreciated
Competing interests: No competing interests
The authors provide a concise and pragmatic overview of the management of suspected penicillin allergy. They correctly refer to the importance of skin testing but omit to specify that this usually means prick and intradermal skin testing.
The confusion is compounded by the BMJ publishing a large colour picture of a patch test: an investigation performed by dermatologists for suspected contact dermatitis to external allergens and singularly useless in the investigation of penicillin allergy.
In the interest of getting the right patient to the right specialist first time apply this broad rule of thumb to allergy referrals. If a reaction to an inhaled, ingested or injected agent is suspected then refer to an allergist. If dermatitis or eczema occurs with an agent applied directly to the skin then refer to a dermatologist for patch testing.
Competing interests: No competing interests
Education editors' reply to Ian Pollock
Thank you for your comments on the image used to illustrate a recent article on penicillin allergy in The BMJ (BMJ 2017; 358 doi:https://doi.org/10.1136/bmj.j3402).
The editors agree that the image did not accurately reflect the content of the article. A correction notice will appear in a future edition of The BMJ.
Competing interests: No competing interests