Contact allergy to local anaesthetics–value of patch testing with a caine mix in the baseline series

Brinca, A; Cabral, R; Gonçalo, Margarida

http://hdl.handle.net/10400.4/1547

Use this identifier to reference this record.

Name:	Description:	Size:	Format:
Repositorio dra Margarida Gonçalo 3.pdf		114.98 KB	Adobe PDF	Download

Send Feedback

Authors

Brinca, A

Cabral, R

Gonçalo, Margarida

Abstract(s)

BACKGROUND: Contact allergy to local anaesthetics is relatively common. Patch testing with benzocaine in the European baseline series is recommended for diagnosis, even though a caine mix has been previously suggested to be superior. OBJECTIVES: To assess the frequency and patterns of contact allergy to local anaesthetics by using a caine mix (benzocaine, tetracaine, and cinchocaine) in the baseline series, and evaluate its efficiency as compared with benzocaine alone. METHODS: We reviewed the results of 2736 patch tests performed between 2000 and 2010, identifying patients with positive reactions to caine mix or to one of seven local anaesthetics. RESULTS: One hundred and twelve patients (4.1%) had at least one allergic reaction to local anaesthetics; 86 were tested with all seven local anaesthetics, resulting in 71 reactions in 53 patients. Cinchocaine gave the most reactions (50.7%); these occurred as a single reaction in 83.3% of patients, mostly with current or past relevance (97%). Benzocaine represented 22.5% of reactions, many of which were non-relevant (44%) or resulting from cross-reactions with para-compounds. CONCLUSIONS: Almost 70% of allergic reactions to local anaesthetics would have been missed if benzocaine had been used as a screening allergen. This study supports a recommendation to replace benzocaine with a caine mix containing cinchocaine in the baseline patch test series.