Introduction

Pigmentary disorders, including vitiligo and melasma, significantly impact patients’ quality of life due to visible skin discoloration. Emerging evidence suggests a role for skin and gut microbiota in these conditions.

Methods

This systematic review analyzed 17 studies focusing on the association between microbiota and pigmentary diseases, specifically vitiligo and melasma. Databases including PubMed, Scopus, Web of Science, Science Direct, Embase, and Magiran were comprehensively searched without initial language restriction, followed by a detailed quality assessment of eligible studies.

Results

The included studies consistently demonstrated significant microbial dysbiosis in pigmentary disorders. In vitiligo patients, microbial diversity was notably decreased in lesional skin, alongside gut microbiota imbalances characterized by reduced proportions of beneficial bacteria, such as Bacteroidetes relative to Firmicutes. Melasma patients exhibited distinct gut microbiota alterations potentially impacting estrogen metabolism.

Conclusions

Emerging evidence suggests that disruptions in skin and gut microbiota may contribute to the development of pigmentary disorders through immune modulation and oxidative stress. Preliminary findings support the therapeutic potential of microbiota-modulating inter­ventions such as probiotics and synbiotics. However, further research is necessary to validate these interventions and optimize personalized treatment approaches aimed at improving patient outcomes.