painful rash on hands with different skin tones

painful rash different skin tones raised help dermatitis allergies dermatoses affect pigmentation dermatological background hand person disease health illness psoriasis dermatology allergy eczema infection problem body symptom itch allergic human reaction epidermis redness irritation sickness urticaria scabies arm sign derma herpes pimple sick scratch spot itching patient itchiness hives ill hands tones crying out for help allergies regardless pigmentation patients