Contact sensitization in venous eczema: Preliminary results of patch testing with Indian standard series and topical medicaments

Background and Aims: Elimination of allergens/topical medications causing contact dermatitis in venous eczema, which poses a significant problem in its chronicity and treatment, provides the basis for better therapeutic outcome. Our objective was to determine the pattern of contact sensitization in venous eczema patients in Himachal Pradesh (India).
Methods: Thirty-four patients (M:F, 31:3) and 10 controls (M:F, 6:4) were patch tested with Indian standard series and 10 commonly used topical medicaments.
Results: Positive patch test results were seen in 50% (M:F, 16:1) of the patients. Common allergens were Fragrance mix (15%), p-phenylendiamine (15%), nickel (9%), wool alcohol (9%), chinoform (9%), balsum of Peru (5%), cobalt chloride (5%), potassium dichromate (3%), epoxy resin (3%), thiuram mix (3%) and formaldehyde (3%). Only sisomycin and miconazole among the topical medications elicited a positive patch test reaction in 3 and 5% patients, respectively. Neomycin contact sensitivity was not seen in any of the patients. One patient who had exacerbation of venous eczema following accidental application of topical diclofenac showed a positive patch test reaction to it.
Conclusions: Patch test should be used to identify the topical agents that may be responsible for perpetuation or aggravation of eczema, especially in patients who do not improve despite adequate treatment of other underlying cause(s).

Keywords
Dermatitis medicamentosa, gravitational eczema, miconazole, patch testing, sisomycin, stasis dermatitis