The phenomenon of fingers turning blue is termed as blanching. The fingers and toes are found to be changing their color when they are kept in cold temperatures, undergo stress, or if the blood supply is not properly functioning in that area. Some of the reasons for the hands or fingers to turn blue are found to include: inflammation of small blood vessels, cryoglobulinemia, frostbite, peripheral artery disease, necrotizing vasculitis, Raynaud’s phenomenon, systemic lupus erythematosus, and scleroderma.
Generally, the people with hypothyroidism will complain that their hands and feet are cold. These symptoms will diminish as the person starts taking treatment for hypothyroidism. If the symptoms persist for long, then the person has to be monitored for Raynaud’s phenomenon. The disease called Raynaud’s phenomenon involves a break in the flow of blood to the fingers and toes because of muscle spasms in the blood vessels. The causes for this phenomenon are listed as follows: entering an air-conditioned room, going out in cold temperatures, having a drink that has ice in it held in the hands, keeping the hands in the freezer, keeping the hands in cold water, and mental stress.
In the Raynaud’s process, the area of the body that is affected will turn white. Later, when the oxygen stops reaching that area, that particular body part will turn blue. The area that is affected might become inflamed, and it can have a tingling sensation and a painful throbbing sensation. The symptoms might disappear very soon or they might persist for a longer period. The Raynaud’s condition sometimes is observed as the secondary problem for several other ailments like: Grave’s disease, autoimmune disease, lupus, Sjogren’s syndrome, scleroderma, Hashimoto’s disease, and rheumatoid arthritis. The other conditions that are studied to be causing the hands to turn blue are: bruising, shaken baby syndrome, congenital heart defects, shock, and blood clots.