Pathology & Treatments of the Skin

1. Pathology & Treatments of the Skin Chapter 12

2. Pathology Sebaceous Glands

3. Sebaceous Glands • Acne vulgaris • Comedo • Formed by the buildup of sebum and keratin in a hair follicle • When the sebum plug is exposed to air it oxidizes and becomes a blackhead • Sebaceous cyst • Contains yellow, fatty material • http://www.youtube.com/watch?v=iEeMJgV75nQ&feature=player_detailpage

4. Sebaceous Glands • Seborrhea • Any of several conditions in which there is an overproduction of sebum • Seborrheic dermatitis • Inflammation of the upper layers of the skin, caused by seborrhea • Results in scaling of the scalp known as dandruff • In newborns, known as cradle cap

5. Sebaceou Glands • Seborrheic keratosis • Benign flesh-colored brown or black skin tumor

6. Pathology Sweat Glands

7. Sweat Glands • Anhydrosis • Condition of lacking or being without sweat • Hyperhidrosis • A condition of excessive sweating • Diaphoresis • Profuse, but not necessarily excessive, sweating • Miliaria • Aka heat rash, or prickly heat • An inflammation caused by trapped sweat

8. Pathology Hair

9. Hair • Hirsutism • Abnormal hairiness • Usually refers to the appearance of male body hair or facial hair patterns in the female • Female pattern baldness • A condition in which the hair thins in the front and on the sides and sometimes on the crown. Rarely leads to total hair loss • Male pattern baldness • Common hair loss pattern in men, with the hairline receding from the front to back until only a horseshoe-shaped area remains

10. Hair • Alopecia • Aka baldness • Alopecia areata • Autoimmune disorder with well defined bald areas, usually on the scalp and face • Alopecia capitis totalis • Loss of all the hair on the scalp • Uncommon • Alopecia universalis • Total loss of hair on all parts of the body

11. Pathology Nails

12. Nails • Clubbing • Abnormal curving of the nails that is often accompanied by enlargement of the fingertips • Can be hereditary or caused by COPD (chronic lack of oxygen) • Koilonychia • Spoon nail • Malformation in which the outer surface is concave

13. Nails • Onychia aka onychitis • Inflammation of the matrix of the nail • Onychocryptosis • Ingrown toenail • Onychomycosis • Any fungal infection of the nail • Difficult to treat • May cause nail to turn yellow, brown, or black, and become thick or brittle

14. Nails • Onychophagia • Nail biting • Paronychia • Acute or chronic infection of the skin fold at the margin of a nail • Subungual hematoma • Usually caused by an injury • A collection of blood trapped in the tissues under a nail

15. Pathology pigmentation

16. Pigmentation • Albinism • An inherited deficiency or absence of pigment in the skin, hair, and eyes • Chloasma • Aka melasma or mask of pregnancy • Characterized by brownish spots on the face during pregnancy. Usually disappears after delivery

17. Dyschormia • ANY disorder of the pigmentation of the skin or hair • Melanosis • Condition of unusual deposits of black pigment in different parts of the body • Vitiligo • Loss of melanocytes results in milk white areas of skin bordered by normally pigmented areas. Unpigmented skin is extremely sensitive to sunburns

18. Pathology Surface lesions

19. Surface Lesions • Lesion • a pathologic change of the tissues due to disease or injury

20. Surface Lesions • Contusion • An injury that does not break the skin • Characterized by swelling, discolorations, and pain • Ecchymosis • Aka bruise • Purplish area cause by hemorrhaging within the skin

21. Surface Lesions • Nevi • Aka moles • Develop from melanocytes • Dysplastic nevi are atypical mole that may develop into skin cancer

22. Surface Lesions • Nodule • A small, solid bump • A cyst is a nodule • Verrucae • Aka warts • Skin lesions caused by the human papillomavirus • Plantar warts develop on the sole of the foot • Petechiae • Small pinpoint hemorrhages • Smaller versions of ecchymoses

23. Fluid-filled lesions

24. Fluid-filled Lesions • An abscess is a localized collection of purulent exudate (pus) within a circumscribed area

25. Lesions through the skin

26. Lesions Through the Skin • Abrasion • Superficial layers of the skin are scraped or rubbed away • Laceration • A torn or jagged wound or an accidental cut • Puncture wound • A deep hole made by a sharp object such as a nail • Risk of infection, especially tetanus, is greater with this type of wound

27. Lesions Through the Skin • A decubitus ulcer, aka pressure ulcer or bedsore, is an ulcerated area caused by prolonged pressure that cuts off circulation to a body part

28. birthmarks

29. Birthmarks • Port-wine stain • Large, reddish purple discoloration of the face or neck • Strawberry hemangioma • Soft, raised birthmark • This dark, reddish purple growth is a benign tumor made up of newly formed blood vessels • Usually resolve without treatment by about age seven

30. General skin conditions

31. General Skin Conditions • Dermatitis • Contact dermatitis – localized allergic response caused by contact with an irritant or allergen • Dermatosis – a general term used to denote any skin lesion or group of lesions or eruptions of any type that are NOT associated with inflammation • Eczema – an acute or chronic skin inflammation characterized by erythema, papules, vesicles, pustules, scales, crusts, scabs, and possibly itching. Symptoms may occur alone or in combination

32. General Skin Conditions • Erythema – any redness of the skin such as a nervous blush, inflammation, or mild sunburn • Lupus erythematosus – an autoimmune disorder that is characterized by a red, scaly rash on the face and upper trunk • Lipedema – an abnormal swelling due to the collection of fat and fluid under the skin, usually between the calf and ankle • Pruritus – aka itching, is associated with most forms of dermatitis

33. General Skin Conditions • Psoriasis – a chronic autoimmune disorder, characterized by itchy red papules covered with silvery scales that occur predominantly on the elbows, knees, scalp, back, and buttocks • Purpura – characterized by hemorrhage into the skin that causes spontaneous bruising • Rosacea – a chronic condition of unknown cause that produces redness, tiny pimples, and broken blood vessels. Usually occurs on the central area of the face and appears most often in people with a fair complexion.

34. General Skin Conditions • Scleroderma – an autoimmune disorder that causes abnormal tissue thickening usually starting on the hands, feet, or face. Some forms of the disease spread to other body systems and can be fatal. • Urticaria – aka hives • Xeroderma – excessively dry skin

35. Bacterial skin infections

36. Bacterial Skin Infections • Furuncles • Aka boils • Large tender, swollen, areas caused by staphylococcal infection around hair follicles • Carbuncle • A cluster of furuncles that result in extensive sloughing of skin and scar formation • Cellulitis • A diffuse infection of connective tissue with severe inflammation within the layers of the skin

37. Bacterial Skin Infections • Gangrene • Tissue necrosis that is usually associated with a loss of circulation. The tissue death is followed by bacterial invasion that causes putrefaction (Putrefaction is decay that produces foul-smelling odors) • Impetigo • A highly contagious bacterial skin infection with isolated pustules that become crusted and rupture

38. Bacterial Skin Infections • Anthrax • Contagious disease of warm-blooded animals caused by the Bacillis anthracis bacterium. • Cutaneous anthrax causes black sores on the skin • Inhalation anthrax causes severe respiratory symptoms

39. Fungal skin infections

40. Fungal Skin Infections • Tinea – aka ringworm. Fungal skin disease • Tinea capitis • Found on the scalps of children • Tinea pedis • Athlete’s foot • Tinea cruris • Jock itch • Dermatomycosis • Tinea versicolor • Fungal infection that causes white to light brown areas on the skin

41. Parasitic skin infestations

42. Parasitic Skin Infestations • Scabies - infestation with the itch mite • Pediculosis – infestation with lice • Pediculosis capitis • Head lice • Pediculosis corporis • Body lice • Pediculosis pubis • Pubic hair lice

43. Skin growths

44. Skin Growths • Callus • A thickening of part of the skin on the hands or feet caused by repeated rubbing • Clavus, or corn is a callus in the keratin layer of the skin covering the joints of the toes • Cicatrix • A normal scar resulting from the healing of a wound • Granulation tissue • Normally forms during the healing of a wound

45. Skin Growths • Granuloma • General term for small knot like swelling of granulation tissue • Keratosis • Any skin growth such as a wart or a callus, in which there is overgrowth and thickening of the skin • Keloid • An abnormally raised or thickened scar that is usually smooth and shiny

46. Skin Growths • Lipoma • A benign fatty deposit under the skin that causes a bump • Papilloma • A benign epithelial tumor that projects from the surrounding surface

47. Skin Growths • Polyp • General term used most commonly to describe a mushroom like growth from the surface of a mucous membrane • Have many causes and are not necessarily malignant • Rhinophyma • Bulbous nose • Hyperplasia of the tissues of the nose often associated with rosacea • Skin tags • Small flesh-colored or light brown growth that hang from the body by fine stalks

48. Skin cancer

49. Skin Cancer • Actinic keratosis – precancerous skin lesion caused by excessive exposure to the sun. Are raised rough, dry, or scaly spots that are tan, brown, gray, or red • Basal cell carcinoma – a malignant tumor of the basal cell layer of the epidermis. Found mainly on the face, is the most frequent and least harmful type of skin cancer. Slow growing and rarely spreads to other parts of the body. Smooth and raised and have a depression in the center. Pink and tend to bleed easily. Picture on page 227.

50. Skin Cancer • Epithelioma • Benign or malignant tumor originating in the epidermis that may occur on the skin or mucous membranes • Malignant melanoma • Skin cancer derived from cells capable of forming melanin • Usually asymmetrical, have irregular borders and mixed colors