Background: Chronic actinic dermatitis is usually controlled under systemic immunosuppressive drugs. We report herein two patients successfully treated with topical tacrolimus.
Case reports: Two men aged 60 and 70 years were treated for chronic actinic dermatitis for two years using systemic immunosuppressive drugs. Due to drug intolerance and treatment resistance, systemic treatment was substituted by topical tacrolimus. Cutaneous lesions improved dramatically within two months but withdrawal of daily application was immediately followed by recurrence of the lesions.
Discussion: Our cases, together with the 10 others reported in the literature, confirm the efficacy of topical tacrolimus in the treatment of chronic actinic dermatitis. Since tacrolimus chiefly targets activated T lymphocytes, it has been successfully deployed in various inflammatory dermatoses and its use is logical in the treatment of chronic actinic dermatitis. While dramatic improvement is achieved within a few weeks in this indication with twice-daily applications of tacrolimus ointment 0.1%, symptoms recur rapidly on dosage reduction, and extremely long-term, or even lifelong, treatment is thus probably needed. Topical tacrolimus application has been shown to be safe for periods of three years. However, the peculiar mechanism of chronic actinic dermatitis with a pronounced imbalance in T-cell subsets raises the question of theoretical risk of carcinogenicity of tacrolimus applications, and this, together with the prolonged duration of treatment, calls for long-term follow-up of chronic actinic dermatitis patients.