J. Lai-Kwon , L. Ly , J. Su , M. Tam
Alcohol swabs are routinely used to disinfect skin prior to
procedures. Despite their widespread use, allergic contact
dermatitis secondary to alcohol swabs has not been widely
reported.
We report a case of a 12 year old female with wound and
intravenous cannula site allergic contact dermatitis post
neurosurgery. The patient was patch test positive to
Briemarpak® alcohol swabs (Briemar Nominees Pty Ltd,
Victoria, Australia) but negative to the individual allergens
in the swab (70% isopropyl alcohol and 1% chlorhexidine).
This strongly suggests a new hapten formed by the interaction
of the individual swab ingredients into a compound
allergen which was responsible for the patient’s symptoms.
There were no reactions to allergens from tape, local anaesthetic
or antiseptic series.
This case raises the possibility that alcohol swab allergies may masquerade as reactions to tapes and topical local anaesthetics, as they are often used in similar scenarios eg. venepuncture. Avoidance of these products in this child resulted in unnecessary patient distress, with insertion of intravenous cannulas without topical local anaesthetic. Delay in identifying the correct allergen also led to prolonged generalisation of her dermatitis and secondary staphylococcal impetiginisation.
Allergic contact dermatitis to alcohol swabs should therefore
be considered in the assessment of suspected tape and
topical local anaesthetic allergies, particularly in paediatricpopulations to minimise patient harm. We recommend patch testing the entire swab as testing for individual allergens can yield negative results.