Hello, For some years now I have been getting sometimes red, hard bumps (on my stomach ), or white hard ones on my arms, face, and upper legs. When I scratch them (because they are somewhat itchy), they callous and then leave behind a small scar . I have seen a derm. about these, and they did not know what it could be. (The ones on my stomach seem to appear with more frequency when I am stressed.) I d appreciate any help with this. : )