Dermatology

• Dermatology is the medical specialty that studies the anatomy and physiology of the integumentary system
• The integumentary system covers most of the body's surface and consists of the skin, nails, and subcutaneous tissue
• Functions of the integumentary system include protection, repair, sensation, synthesis of vitamin D, and thermoregulation
• The skin consists of two layers: Epidermis (outermost layer made of epithelial tissues) and Dermis (thick layer below the epidermis made of connective tissue)
• Hypodermis (subcutaneous tissue) lies beneath the dermis and is composed of adipose tissue and loose areolar tissue
• Dermatitis is any infection or inflammation of the skin
• Edema is swelling from excessive fluid moving into the dermis or subcutaneous tissue
• Hemorrhage is the release of blood into the skin due to injury to blood vessels
• Lesion is any area of visible damage on the skin or a variation from normal skin
• Neoplasm is a new growth on the skin, benign or malignant
• Pruritus is the condition of itching, often associated with allergic reactions on the skin
• Rash is a red or pink skin lesion that can be flat or raised, itchy or non-itchy
• Xeroderma is excessively dry skin
• Albinism is a genetic mutation where melanocytes do not produce melanin, resulting in a lack of skin, hair, and eye coloration
• Cyanosis is a bluish-purple discoloration of the skin and nails
• Erythema is red discoloration of the skin, which can be local or over large areas
• Jaundice is yellowish discoloration of the skin, mucous membranes, and sclera due to liver inability to process bilirubin
• Necrosis is gray-to-black skin discoloration due to skin death from various causes
• Vitiligo is an autoimmune disease where melanocytes are destroyed, leading to depigmentation patches on the skin
• Abrasion is a sliding or scraping injury that mechanically removes the epidermis
• Blister is a fluid-filled sac caused by repetitive rubbing injury
• Burns can be superficial, partial-thickness, or full-thickness, caused by various sources like heat, chemicals, or radiation
• Callus is a thickened, elevated pad on the dermis due to repetitive rubbing
• Cicatrix is collagen that forms as an injury heals, resulting in a scar
• Excoriation is a superficial injury with a sharp object creating a linear scratch on the skin
• Keloid is a firm, abnormally large scar that grows larger than the original injury due to collagen overproduction
• Laceration is a linear penetrating wound with clean-cut or torn edges
• Decubitus ulcer is an ulcer in the skin caused by constant pressure that decreases blood flow over bony areas
• Abscess is a localized pus-containing pocket under the skin caused by a bacterial infection
• Cellulitis is an infection and inflammation of the connective tissues of the skin
• Shingles is an infection with the herpes virus, involving vesicles, erythema, edema, and pain
• Verruca is a rough, irregular skin lesion caused by the human papillomavirus, known as a wart
• Tinea is a fungal infection of the skin, with different types like Tinea capitis, corporis, cruris, and pedis
• Pediculosis is an infestation of lice and their eggs, while scabies is an infestation of parasitic mites under the skin
• Contact dermatitis is dermatitis caused by physical contact with an allergen or irritant
• Urticaria is a local allergic reaction causing raised areas of redness and edema, often due to food, plants, or insect bites
• Actinic keratosis is raised, rough areas due to chronic sun exposure
• Hemangioma is a mass of superficial, dilated blood vessels present at birth
• Lipoma is a rounded growth of adipose tissue in the skin
• Nevus is a lesion present at birth, coming in various shapes and colors like moles or birthmarks