I have a single white patch on my thumb since about 45-50 days which has not changed. It sometimes appear white and sometimes pink. Size is 8 mm by 4 mm. It seems that it is slightly raised though I am not sure. However, it has lost some sensation of touch and I dont get any sensation when I scratch it on surface. No other patch on body. There is no itching Or irritation.I am taking medicine of vitiligo as per local dermatologist which has produced no result till now after 15 days. I do not suffer from any other autoimmune condition. I want to confirm whether it is indeed vitiligo and if yes, what is the type and outlook for future spread. Is there any possibility of any any other underlying cause.