An Interventional, Comparative, Prospective Study to Determine Optimum Concentration of Intralesional Triamcinolone Acetonide in Treatment of Alopecia Areata

Dear Editor, Intralesional corticosteroid (ILS) is first-line therapy in adults with limited patchy alopecia areata. Triamcinolone acetonide is the most common ILS used.[1,2] Chu et al.[3] in their pilot study compared the benefit of 3 triamcinolone acetonide concentrations (2.5, 5, and 10 mg/mL) in the treatment of limited patchy scalp alopecia areata. The authors in this study found the dose of 2.5 mg/mL to be as beneficial as 5 or 10 mg/mL. The advantage of using the lowest effective concentration is that it minimizes local side effects like skin atrophy and telangiectasia and also reduces the potential for systemic adrenal suppression. It also allows for injection of a greater volume, increasing the maximal treatment area. To our knowledge, there are no studies determining the minimum optimal concentration of intralesional triamcinolone acetonide (less than 2.5 mg/ml). We performed a comparative study for 2 triamcinolone concentrations (1.25 and 2.5 mg/ml). After institutional ethics committee approval, subjects (age 12–60 years) with limited patchy alopecia areata with scalp involvement <20% were recruited. Exclusion criteria included pregnant or lactating women, any local active infection, and history of treatment within past 3 months. Amongst patients with multiple alopecic patches, two patches of comparable size were selected and randomly one patch was assigned for injection with 2.5 mg/ml and other for 1.25 mg/ml of triamcinolone acetonide [Figure 1]. In patients with single large alopecic patch, the patch was divided into two equal size with 1 cm gap in the middle of the patch, the right half was injected with 1.25 mg/ml, while the left half was injected 2.5 mg/ml. The injections were repeated every month for 6 months. Standardized photographs of alopecic patches were taken at baseline and the some of the follow-up visits (at 1, 3, and 6 months). The response was calculated in terms of percentage hair regrowth achieved after 6 months and divided into 5 grades [Table 1]. After taking written informed consent, a total of 70 alopecic patches in 35 patients were treated. Of the recruited patients, 23 were men and 12 were women. The mean age of the study subjects was 27.5 years (12–65 years). Among patches receiving concentration of 2.5 mg/ml maximum, 22/35 patches (62.8%) showed more than 75% hair regrowth, while with 1.25 mg/ml concentration maximum, 26/35 patches (74%) failed to show >50% hair regrowth. Further with 1.25 mg/ml, none of the patches showed more than 75% hair regrowth. The difference of response between two groups was statistically significant with P value < 0.05 [Figure 2]. None of the subjects had any adverse effects. This study shows that 2.5 mg/ml is better than 1.25 mg/ml of triamcinolone acetonide in terms of hair regrowth and can be considered as the minimal effective concentration of triamcinolone acetonide for management of alopecia areata.Figure 1: (a) A representative image of a patient with 2 comparable alopecic patches in which the left patch received 2.5 mg/ml, while the right patch received 1.25 mg/ml. (b) Post 6 months response in the same patient, left patch (receiving 2.5 mg/ml) showed grade 4 hair regrowth, while the right patch (receiving 1.25 mg/ml) showed grade 2 hair regrowthTable 1: Response at the end of 6 months was graded into 5 grades, 0–IVFigure 2: Bar diagram showing percentage of hair regrowth achieved after 6 months of therapy with 2.5 mg/ml and 1.25 mg/ml concentration of triamcinolone acetonide (ILS). The x axis denotes the percentage of hair regrowth, while the y axis denotes the number of patchesFinancial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest. Use of artificial intelligence (AI) The preparation of this manuscript was carried out entirely by the author without the use of artificial intelligence technologies.