Efficacy of Topical Tyrosine Versus Topical 5-Fluorouracil With Fractional Erbium YAG Laser in Focal Vitiligo: A Randomised Clinical Trial

Vitiligo is an autoimmune disorder affecting the skin, specifically targeting pigment-producing melanocytes, leading to noticeable regions of depigmentation characterized by white spots. Two major clinical forms of vitiligo are recognized: non-segmental vitiligo, the most common type, usually presenting with symmetrical lesions, and segmental vitiligo, which manifests as unilateral depigmentation.

The exact pathogenesis of vitiligo remains unclear. However, it is believed to be a complex process involving genetic susceptibility, metabolic disturbances related to oxidative stress, impaired melanocyte adhesion to the epidermis, and immune mechanisms including both innate and adaptive immunity, ultimately leading to selective melanocyte destruction. Nevertheless, none of these mechanisms alone can completely explain melanocyte loss, suggesting that vitiligo is a multifactorial disorder.

The management of vitiligo aims to halt disease progression, stimulate repigmentation, and prevent relapse, with repigmentation largely driven by melanocyte stem cells in hair follicles that can migrate and restore functional melanocytes to depigmented areas.

Immune modulators, such as topical steroids, topical calcineurin inhibitiors, phototherapies, and systemic therapy like oral steroids, are the mainstay of traditional treatments. However, these options are still not ideal, which prompts research into novel vitiligo treatments. There is still a need for workable and well-tolerated therapeutic choices, even if treatment must be tailored to each patient and particular lesions.

5-Fluorouracil (5-FU) is a hydrophilic pyrimidine analogue with significant anticancer activity and limited water solubility, first discovered in the 1950s by Heidelberger through the introduction of a fluorine atom at the fifth position of the uracil molecule.