Yes, SCLERODERMA is a Scrabble word!

Letter values in Scrabble US: S 1, C 3, L 1, E 1, R 1, O 1, D 2, E 1, R 1, M 3, A 1.

Is it a valid word?

SCLERODERMA is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

an autoimmune disease that affects the blood vessels and connective tissue; fibrous connective tissue is deposited in the skin
genus of poisonous fungi having hard-skinned fruiting bodies: false truffles

Also: dermatosclerosis, genus scleroderma.