blue hyperpigmented disorders may also be melanotic in which there is a normal number of epidermal melanocytes , but melanin pigment is present in the upper dermis ( eg , gray/slate pigmentation in riehl 's melanosis ) , melanocytotic in which melanocytes are present in both the epidermis and dermis ( eg , blue pigmentation in nevus ota and mongolian spot ) , and nonmelanotic hyperpigmentation in which pigment is present in the deep dermis ( eg , blue pigmentation in tattoos ) .
C0206736
blue
C0011646
dermis