The causes of vitiligo
Even though this disease has been known for centuries, its causes are still unknown. Plutarch wrote that Lucius Cornelius Sulla –the Roman general lived in the I century B.C.- had a “rough and white-patched facial skin” and that an insolent Athenian said about him: “Sulla is a blackberry covered in flour”.
There has been much speculation about the causes of vitiligo; according to the majority of researchers it is due to genetic susceptibility and to the triggering action of stress conditions, prolonged physical traumas or micro-traumas or other pathologies. What is sure is that multiple factors are involved in the etiopathogenesis of vitiligo.
A special medical branch, known as psycho-neuro-immunology, studies the interactions among psyche, nervous system, immune system and skin. Vitiligo too could form part of that group of skin diseases caused by an impaired balance of these strictly interdependent elements.
Melanin and melanocytes
Examining under the microscope a fragment of skin taken from the achromic area, the only certainty is the absence or damage of melanocytes and the complete absence of melanin –the pigment responsible for the color of skin, hair, eyes and some mucosal tissues. Melanin is produced by melanocytes, cellular elements disseminated in the innermost skin layer, the basal layer.
Melanocytes are photoreceptors, i.e. cells that allow the skin absorb the light energy required to trigger all the processes promoting melanin production.
Melanocytes therefore play a crucial role both in the onset and in the healing of vitiligo. For still virtually unknown reasons melanocytes can be indeed reduced in number, replaced by other cells or unable of producing melanin.
In this case the cells moving up from the basal layer to the upper skin layers will be lacking in melanin and, once they reach the surface, they will cause an achromic patch. This patch can be re-pigmented through a therapy able to restore or reactivate melanocytes.