British Society for Cutaneous Allergy

CD01 Updating the British Society for Cutaneous Allergy medicament series: just what the doctor ordered S. Arianayagam, S. Morrow, C. Bertram, D. Buckley, M. Chowdhury, P. Divekar, S.A. Ghaffar, C. Holden, G. Johnston, A. Mughal, E. Nic Dhonncha, C. Reckling, R. Sabroe, K. Scharrer, N. Stone, D. Thompson, S. Wakelin, M. Wilkinson and S. Cooper Oxford University Hospitals NHS Trust, Oxford, U.K.; Royal Infirmary of Edinburgh, Edinburgh, U.K.; Royal United Hospital Bath NHS Trust, Bath, U.K.; University Hospital of Wales, Cardiff, U.K.; Royal Cornwall Hospitals NHS Trust, Truro, U.K.; Ninewells Hospital & Medical School, Dundee, U.K.; Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield, U.K.; University Hospitals of Leicester NHS Trust, Leicester, U.K.; Swansea Bay University Health Board, Swansea, U.K.; South Infirmary Victoria University Hospital, Cork, Ireland; East Kent Hospitals University NHS Foundation Trust, Canterbury, U.K.; United Lincolnshire Hospitals NHS Trust, Lincoln, U.K.; Aneurin Bevan University Health Board, Newport, U.K.; Sandwell and West Birmingham Hospitals NHS Trust, Birmingham, U.K.; Imperial College Healthcare NHS Trust, London, U.K.; and Leeds Teaching Hospital NHS Trust, Leeds, U.K. Topical medicament allergy may complicate treatment of skin conditions and is important to identify. The current British Society for Cutaneous Allergy (BSCA) medicament series comprises 20 allergens and was last updated in 2007. This study aimed to update the BSCA medicament series by auditing data from patch test centres, collating outcomes and identifying low-yield allergens to be removed and high-yield allergens to be added. We performed a retrospective review of patients tested to the medicament series between 1 August 2017 and 31 July 2019, in 16 centres. We recorded the number tested, allergens tested and the number of positive reactions to each allergen. We then calculated the positive patch test rate for each allergen. The cut-off for excluding currently recommended allergens was set at a positive rate < 0.1%. A positive rate ≥ 0.1% was required to consider addition of new allergens to the series. The BSCA committee reviewed the data to finalize the series. A total of 5547 patients were tested to the medicament series. There was a variation in the number of medicament allergens tested between centres (mean 22; range 18–28). The proportion of patch-test patients tested to the medicament series varied significantly between centres (mean 33%; range 1–99%). Eighteen of 20 allergens in the current BSCA series had positive rates ≥ 0.1%. Overall, five allergens were considered for removal from the medicament series, because of inclusion in other series or low positive detection rates. Seven allergens not currently included in the BSCA series showed a positive rate ≥ 0.1% and four of these were recommended for addition. Five new allergens were proposed for inclusion in an extended medicament series, based on case reports and general usage, for evaluation and re-audit. This audit highlights the importance of regular review of the BSCA recommended patch series in order to maintain a test series that is relevant to the tested population. This allows us to maximize the detection of important allergens, while minimizing testing of unnecessary allergens.