Abnormal Biochemical Parameters in Vitiligo

Since none of the hypothetical concepts, acquired or congenital, can totally explain the genesis of vitiligo and since it is well known that depletion of skin melanin is the main criterion for diagnosis of the disease, to get a better understanding of the etiology of the disease, a search for 

Urinary indole profile Larger excretion of 5-hydroxyindole acetic acid, 5-hydroxy tryptamine, and kynurenine are consistently present but indican is absent 48,135, 229 

Urinary anthranilic acid. Higher than normal 48,229 

Blood- and skin-SH constant Higher than normal 135 

Skin nickel, cobalt, and copper level Insignificant change after depigmentation 50 

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