1 Integumentary System

2 Objectives After studying this chapter, you will be able to: Name the parts of the Integumentary system and discuss the function of each part. Name the common diagnoses, laboratory tests and clinical procedures used in testing and treating the Integumentary system.

3 Objectives Part 2 Define the major pathological conditions of the Integumentary system. Define surgical terms related to the Integumentary system. List common pharmacological agents used in treating the Integumentary system.

4 Structure and Function Skin is the largest organ of the body, and serves to: Protect against injury Protect against the sun UV rays Prevent entry of harmful microorganisms Maintain the proper internal body temperature Excrete waste materials through perspiration Function as a sense organ

5 Three Layers of Skin Three Layers of the Skin Epidermis or stratified squamous epithelium Stratum corneum Basal layer includes melanocytes Dermis or corium Subcutaneous Nerves, vessels, glands, hair follicles Connective tissue (mostly lipocytes)

6 Epidermal Layer Outermost skin layer Consists of several sublayers Basal layer contains melanocytes Nonvascular bottom sublayer where new cells are produced that push up & fill w/ keratin to produce waterproof layer epidermis

7 Dermal Layer Also called the corium Contains two sublayers Holds many capillaries, nerve endings, glands, and hair follicles Collagen fibers are found in the connective tissue and when collagen fibers stretch, they form striae dermis

8 Subcutaneous Layer Also called the hypodermis Found between the dermal layer and the inner organs Consists of adipose and some fibrous tissue Fatty tissue protects inner organs and maintains body temperature Blood vessels and nerves are present subcutaneous

9 Hair Hair grows out of the epidermis to cover parts of the body. The shaft is what we see and the root lies below the surface of the skin. Hair color is determined by the presence of melanin. Baldness or alopecia may result from heredity, disease, injury, or chemotherapy.

10 Nails Nails: plates of hard keratin cover the dorsal surface of the fingers and toes. Protection, grasping, scratching lunula or whitish half-moon is an area where keratin and other cells have mixed with air. cuticle narrow band of epidermis that surrounds the base or bottom of nails.

11 Glands Sudoriferous: aka sweat glands The excretion of sweat is called diaphoresis. Sebaceous: oil glands Produce sebum to lubricate hair & skin Protection from pathogens

12 Skin Lesions Both abnormalities and certain internal diseases show dermatological symptoms. Skin Lesions Primary: areas of tissue that are altered because of a pathological condition. Secondary: result from changes in primary lesions. Vascular: blood vessel lesions that show through the skin.

13 Primary Lesions Macule or Patch –Flat –Discolored light or dark Vesicle –Small blister Bulla –Large blister

14 Primary Lesions Pustule –Pus filled blister Papule –Elevated solid mass

15 Primary Lesions Plaque –Small, itchy patch of skin Nodule –A large pimple or small node

16 Primary Lesions Tumor –Abnormal tissue growth or swelling Wheal –Smooth, elevated area associated with allergies

17 Secondary Lesions Abrasion –Superficial Usually epidermis, part of dermis involved Ulcer –Caused by prolonged pressure that cuts off circulation to a body part

18 Secondary Lesions Excoriation –A scratched area of skin usually covered in dried blood Fissure –A deep crack in the skin

19 Secondary Lesions Crust –Dried blood and pus Keloid –Firm, raised scar Cicatrix –Scar

20 Pathology Caused by Viruses Exanthematous viral rash: –Appear during certain viral infections Herpes simplex Type 1(cold sores) Herpes simples Type 2 (genital herpes) Herpes zoster (shingles)

21 Pathology Caused by Viruses Verruca –Warts Plantar wart –Occurs on sole of foot

22 Pathology Caused by Bacteria Impetigo –Highly contagious Staph skin infection Cellulitis –Bacterial infection of connective tissue

23 Pathology Caused by Bacteria Gangrene –Necrosis that usually associated with loss of circulation Acne –Overproduction os sebum –Comedoes (blackheads) –Pustules –Nodules

24 Pathology Caused by Fungi Ringworm or tinea –Characterized by intense itching or pruritis. –Can occur on body, scalp, groin, or beard Candidiasis –Yeast infection

25 Vascular Conditions Ecchymosis –Bluish-purple skin mark may be due to injury. Petechiae –Tiny pinpoint ecchymosis.

26 Vascular Conditions Purpura –Extensive skin hemorrhages covering a wide area Rosacea –Appears as red blotches on the skin, especially the nose and cheeks

27 Conditions Related to Pigmentation Vitiligo –Patches with loss of pigment surrounded by patches with extensive pigment Albinism –Rare congenital disorder –Extensive or total lack of pimentation

28 Conditions Related to Pigmentation Nevus –Birthmark Chloasma –Large, pigmented facial patches

29 Conditions Caused by Insects Pediculosis An inflammation with lice usually on the head or genitals. Scabies Contagious skin eruption that often occurs between fingers, on areas of the trunk, or male genitalia and is caused by mites.

30 Conditions Caused by Exposure to Heat, Chemicals, Electricity, Radiation, or Irritants 1 st degree or superficial burn –Skin pink to red w/o blisters –Dry and painful to touch –Heals without scarring 2 nd degree or partial- thickness burn –Blisters and extreme pain –Ruptured blister leaves skin moist and sticky –Heals without scarring

31 Conditions Caused by Exposure to Heat, Chemicals, Electricity, Radiation, or Irritants 3 rd degree or full- thickness burn –Entire skin and subcutaneous tissues involved –Necrosis of involved tissues –Forms scars

32 Chronic Conditions Psoriasis –Hyperkeratosis –Scaly lesions Seborrhea –Over activity of sebaceous glands –Scaly eruptions of face & scalp

33 Nail Inflammation The term onychia or onychitis means nail inflammation. Causes of Nail Inflammation infection irritation fungi Paronychia is an inflammation of the flap of skin overlapping the nail.

34 Skin Cancers Basal cell carcinoma –Malignant tumor of basal cells –Found mainly on face –Most frequent and least harmful type of skin cancer Squamous cell carcinoma –Malignant tumor of squamous epithelium –Quickly spreads to other body systems

35 Skin Cancers Malignant melanoma –Skin cancer derived from cells capable of forming melanin –Occurs in skin at any part of the body and may metastasize quickly to the lungs, liver, and brain

36 Skin Cancers Leukoplakia –Precancerous skin lesion –Caused by excessive exposure to the sun or irritants such as chewing tobacco Kaposi’s Sarcoma –Malignant skin lesion –Assoc with AIDS

37 Benign Neoplasms Corn –Hardening or thickening of skin on a toe Callus –Hard, thickened area of skin

38 Surgical Terms Various types of plastic surgery may involve reconstructing areas of the skin. Other types involve removing part of a growth to test for cancer or removing the entire cancerous growth.

39 Skin Grafts Plastic surgery may involve the use of skin grafts. Types of skin grafts Autograft - skin from own body. Allograft or homograft - donor skin from another person. Heterograft or xenograft - donor skin from one species to another.

40 Methods of Removal Methods used to remove unwanted growths or scrape tissue or discolorations include: Cryosurgery Dermabrasion Debridement and Curettage Removal of tissue by applying cold liquid nitrogen. Use of brushes and emery paper to remove wrinkles, scars, and tatoos. Removal of dead tissue from a wound by scraping.

41 Types of Medication Treatment of skin disorders involves the use of various medications. Types of Medications Chemotherapy uses chemicals that destroy malignant cells. Antibiotics kill or slow the growth of microorganisms on the skin. Emollients are agents that soothe the skin by moistening it or adding oils to it. Astringents decrease the formation of oily material on the skin.

42 Types of Medication Types of Medications Anithistamines: control allergic reactions by blocking histamines Antifungals: kill fungi Parasiticides: kill skin parasites Anti-inflammatory: reduce inflammation Antipruritics: control itching Keratolytics: remove warts and corns

43 Apply Your Knowledge Part 2 Which of the following patients would experience the most pain following their burn injury? Patient A accidentally spilled hot grease on his his right hand and arm resulting in first and second degree burns to the entire area. -OR- Patient B was in his home when his kerosene heater fell on his left lower leg causing complete third degree burns to the area. Answer: Patient A

44 Apply Your Knowledge Part 3 Use the following meanings and build the correct term for each. Medical Term Meaning 1. Inflammation of the skin. 2. Production and excretion of sweat. 3. Any condition caused by fungus. dermatitis hidrosis mycosis

45 Apply Your Knowledge Part 4 Ellen notes a small elevated pimple on her forehead and you realize this lesion is called a: A. macule B. papule C. keloid Is this lesion considered a primary, secondary or vascular lesion? Answer: primary Answer: B. papule