Evaluating the utility of screening corticosteroids found in standard/baseline patch testing series.

To the Editor: Hypersensitivity to topical corticosteroids has been well described, affecting up to 5% of patients.1Matura M. Goossens A. Matura M. Contact allergy to corticosteroids.Allergy. 2000; 55: 698-704Crossref PubMed Scopus (153) Google Scholar Moreover, patients hypersensitive to one topical corticosteroid often react to other corticosteroids.1Matura M. Goossens A. Matura M. Contact allergy to corticosteroids.Allergy. 2000; 55: 698-704Crossref PubMed Scopus (153) Google Scholar, 2Coopman S. Degreef H. Dooms-Goossens A. Identification of cross-reaction patterns in allergic contact dermatitis from topical corticosteroids.Br J Dermatol. 1989; 121: 27-34Crossref PubMed Scopus (299) Google Scholar, 3Baeck M. Chemelle J.-A. Terreux R. Drieghe J. Goossens A. Delayed hypersensitivity to corticosteroids in a series of 315 patients: clinical data and patch test results.Contact Dermatitis. 2009; 61: 163-175Crossref PubMed Scopus (78) Google Scholar Patch testing is commonly used to detect such hypersensitivity. Due to the large number of topical corticosteroids available and limited space within typical standard/baseline patch testing series, a small corticosteroid subset is frequently chosen to screen for corticosteroid hypersensitivity. Current patch testing standard/baseline series have differing recommendations for corticosteroids utilized in screening, depending on the institution performing the testing (Table I). For example, screening corticosteroids in the Mayo Clinic Standard Series are budesonide, tixocortol-21-pivalate, hydrocortisone-17-butyrate, clobetasol-17-propionate, desoximetasone, and triamcinolone acetonide. When clinically indicated, patients are also tested to an expanded corticosteroid series (Supplementary Table I, available via Mendeley at https://data.mendeley.com/datasets/pbh6z5s664/1). This study sought to compare the efficacy of commonly used corticosteroid screening sets in detecting corticosteroid sensitivity.Table ITopical corticosteroids included in the TRUE test, American Contact Dermatitis Society Core Series, European Baseline Series, North American Contact Dermatitis Group Screening Series, and the Mayo Clinic Standard SeriesSeriesTRUE testACDS Core SeriesEuropean Baseline SeriesNACDGMayo Clinic Standard SeriesCorticosteroids included (vehicle)Tixocortol-21-pivalate (povidone)Tixocortol-21-pivalate 1% (pet)Tixocortol-21-pivalate 0.1% (pet)Tixocortol-21-pivalate 1% (pet)Tixocortol-21-pivalate 1% (pet)Budesonide (povidone)Budesonide 0.1% (pet)Budesonide 0.01% (pet)Budesonide 0.1% (pet)Budesonide 0.01% (pet)Hydrocortisone-17-butyrate (povidone)Hydrocortisone-17-butyrate 1% (pet)Hydrocortisone-17-butyrate 1% (pet or alc)Hydrocortisone-17-butyrate 1% (alc)Clobetasol-17-propionate 1% (pet)Clobetasol-17-propionate 1% (pet)Clobetasol-17-propionate 1% (pet)Triamcinolone acetonide 1% (pet)Triamcinolone acetonide 1% (pet)Triamcinolone acetonide 1% (pet)Desoximetasone 1% (pet)Desoximetasone 1% (pet)ACDS, American Contact Dermatitis Society; Alc, alcohol; NACDG, North American Contact Dermatitis Group; Pet, petrolatum; TRUE, thin-layer rapid use epicutaneous. Open table in a new tab ACDS, American Contact Dermatitis Society; Alc, alcohol; NACDG, North American Contact Dermatitis Group; Pet, petrolatum; TRUE, thin-layer rapid use epicutaneous. How well do screening corticosteroids in the standard/baseline series perform, in comparison to the larger corticosteroid series? We assessed the performance of screening corticosteroids in 4 standard series (Thin-layer Rapid Use Epicutaneous [TRUE], American Contact Dermatitis Society Core, European Baseline, and North American Contact Dermatitis Group [or Mayo Clinic Standard] – Table I) against corticosteroid patch tests conducted at Mayo Clinic between 2010 and 2019 (5637 patients). We report the “miss rates” that represent how many untested positive corticosteroid patch tests would have been missed, if a patient were only screened with a baseline series as opposed to a more extensive corticosteroid patch test panel. To determine the miss rate for any given corticosteroid screening set, we divided the missed positive patch tests by the total positive patch tests to all corticosteroids. In this analysis, we excluded any corticosteroid used in each screening set itself to reduce incorporation bias, ie, utilizing screening corticosteroid positivity to define screening success would artificially decrease the miss rate. We found that many positive corticosteroid patch tests would be missed if solely using screening corticosteroids found in standard/baseline series (Table II). Topical corticosteroids in the European Baseline Series had a miss rate of 54.73%. The TRUE test was determined to have a miss rate of 45.56%. The American Contact Dermatitis Society Core Series had a miss rate of 41.96%. Finally, the North American Contact Dermatitis Group and Mayo Clinic series was found to have a miss rate of 31.25% (Table II).Table IISummary of calculated miss rates of various standard/baseline patch test series, based on Mayo Clinic data from 2010 to 2019Patch test seriesTotal positive patch testsTotal positive patch tests that would have been missed∗“Missed” is defined as positive corticosteroid patch tests, when the corresponding screening corticosteroid patch tests were negative.Screening miss rateTRUE Test1808245.56%ACDS Core Series1436041.96%European Baseline Series20111054.73%NACDG/Mayo Standard Series1123531.25%To reduce incorporation bias, corticosteroids used in each screening set were excluded from cognate miss rate analysis.ACDS, American Contact Dermatitis Society; NACDG, North American Contact Dermatitis Group.∗ “Missed” is defined as positive corticosteroid patch tests, when the corresponding screening corticosteroid patch tests were negative. Open table in a new tab To reduce incorporation bias, corticosteroids used in each screening set were excluded from cognate miss rate analysis. ACDS, American Contact Dermatitis Society; NACDG, North American Contact Dermatitis Group. There are a number of limitations to our analysis. Because only a subset of patients with high suspicion of corticosteroid sensitivity underwent testing to our extended series, the miss rates determined may not be fully reflective of the general patch test population, but rather enrich for patients more likely to be hypersensitive to corticosteroids. Furthermore, optimization of these miss rates may be partially constrained by the inherent limitations of patch testing itself and number of allergens placeable due to body surface area/reimbursements. Further investigation is recommended to optimize the use of screening corticosteroids in the detection of patients with corticosteroid allergy. Until then, we propose that corticosteroid testing should be considered in accordance with patients' previous, current, or potential corticosteroid usage. None disclosed.