The reservoir effect of topical steroids in vitiliginous skin: A cross-sectional study.

BACKGROUND: Prolonged and frequent use of topical steroids may lead to decrease in efficacy as well as many local adverse effects. Stratum corneum has a unique property of reservoir effect. AIMS: To study the reservoir effect of topical steroids in a steroid-responsive condition which may enable a decrease in the dosing frequency of topical steroids. METHODS: A cross-sectional study design was used. Patients with at least three vitiliginous patches of more than 2 cm 2 present over the trunk or limbs were included. Exclusion criteria were topical or systemic corticosteroid use within the previous 4 weeks, antihistamine use within the previous 7 days, history of any allergy in the past and immunosuppression. Clobetasol propionate cream was applied on the first vitiliginous area (site A) and fluticasone propionate ointment was applied on the second vitiliginous area (site B). The third vitiliginous area, site C (control site) was left without applying any medication. Histamine-induced wheal suppression test was performed on each site, at the same time of the day, on every consecutive day following steroid application, until the values obtained at sites A and B approached those obtained at site C. SPSS software for Windows, version 16.0 was used for statistical analysis. The mean and standard deviation of the various studied parameters were calculated for various treatment groups and compared using analysis of variance (ANOVA) test. RESULTS: Forty patients were included in the study. The average wheal volumes and average erythema sizes at sites A and B were significantly smaller than the corresponding values at site C for up to 5 days after applying medication (P < 0.001). LIMITATIONS: The presence of a cutaneous reservoir of topical steroid was confirmed based on its suppressive effect on the wheal and flare response to histamine. It is not certain that the concentration that suppresses histamine-induced wheal and flare is sufficient for therapeutic efficacy in vitiligo. CONCLUSION: The reservoir effect of topical clobetasol propionate and fluticasone propionate persisted for 5 days in vitiliginous skin. Hence, it may be possible to reduce the frequency of topical steroid application in vitiligo.

Comparison of clinical efficacy of topical tazarotene 0.1% cream with topical clobetasol propionate 0.05% cream in chronic plaque psoriasis: a double-blind, randomized, right-left comparison study.

BACKGROUND: No controlled data is available till date comparing topical tazarotene and clobetasol in Indian psoriatic patients. OBJECTIVE: The aim was to compare the clinical efficacy of 12 weeks of once-daily tazarotene 0.1% cream with that of once-daily clobetasol propionate 0.05% cream in the treatment of patients with chronic plaque psoriasis. METHODS: About 36 patients with bilaterally symmetrical lesions were enrolled in this double-blind randomized controlled study. A left-right randomized study was conducted. RESULTS: Clobetasol cream was better than tazarotene cream in reducing the erythema throughout the treatment period with statistically significant differences favoring clobetasol at weeks 2, 4, 6 and 8 ( P <0.05). Tazarotene was better in reducing the induration at weeks 2 ( P <0.05), 4, 10 and 12. Clobetasol cream was better in reducing the scaling throughout the treatment period with statistically significant differences favoring clobetasol over the entire treatment period. Treatment success rate was 100% with clobetasol and 88% with tazarotene at the end of week 12 with clobetasol achieving 100% success rate at the end of week 6. Treatment with tazarotene resulted in uniform reduction of plaque elevation and was not associated with the development of hot spots. CONCLUSION: Topical tazarotene 0.1% cream is less effective than topical clobetasol propionate 0.05% cream in the treatment of plaque psoriasis. It has more effect on induration than on erythema and scaling of psoriatic lesions.