CHAPTER 5

Integumentary

System

Skin

• Functions – Protects; melanin provides color

– Regulates body temperature

– Serves as sensory receptor (touch, pressure, pain,

temperature)

– Provides for elimination of body waste

(perspiration)

– First step of synthesis of vitamin D

Integumentary System

• Skin – Also called integument or cutaneous membrane

– Epidermis—outer layer of skin

– Dermis—inner layer of skin

– Subcutaneous layer—consists largely of loose

connective tissue and adipose tissue

• Dermatology – Study of the skin

Integumentary System

• Accessory structures – Hair

– Nails

– Glands

Layers and Structures of the Skin

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Structure of the Nail

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Question

True or False: The epidermal layer

contains most of the skin’s vital

structures.

Answer

False. The dermis actually contains

structures such as hair follicles, pressure

receptors, and glands.

Question

The half-moon we see at the base of our

fingernails is called the _______. a. cuticle

b. lunula

c. nail bed

d. edge

Answer

b. It is derived from the Latin word luna,

meaning “moon.”

Skin Lesions

• Abrasion – Scraping or rubbing away of skin or mucous

membrane as a result of friction to the area

• Example: carpet burn

• Abscess – Localized collection of pus in any body part that

results from invasion of pus-forming bacteria

• Example: pustule = small abscess

Skin Lesions

• Blister – Small, thin-walled lesion containing clear fluid

– Also known as a vesicle

• Bulla – Large blister

Skin Lesions

• Carbuncle – Circumscribed inflammation of the skin and deeper

tissues; contains pus

• Comedo – Typical lesion of acne vulgaris

• Example: whitehead = closed comedo

• Example: blackhead = open comedo

Skin Lesions

• Cyst – Closed sac or pouch in or within the skin; contains

fluid, semifluid, or solid material

• Example: hydrocele = fluid-filled cyst, especially in the

scrotum

• Example: sebaceous cyst = solid-filled cyst

Skin Lesions

• Fissure – Crack like sore or groove in the skin or mucous

membrane

• Example: anal fissure

• Fistula – Abnormal passageway between two tubular organs

or from an organ to the body surface

• Example: rectovaginal fistula

Skin Lesions

• Hives – Circumscribed, slightly elevated lesions on skin;

paler in the center than the surrounding edges

– Also called wheals

• Example: mosquito bite

• Laceration – Tear in the skin

Skin Lesions

• Macule – Small, flat discoloration of the skin; neither raised

nor depressed

• Example: bruises, freckles

• Nodule – Small, circumscribed swelling protruding above the

skin

Skin Lesions

• Papule – Small, solid, circumscribed elevation on the skin

• Example: pimple

• Polyp – Small, stalk like growth, protruding upward or

outward from mucous membrane surface

• Example: nasal polyp

Skin Lesions

• Pustule – Small elevation of skin filled with pus

• Example: small abscess on the skin

• Scales – Thin flakes of hardened epithelium that are shed

from the epidermis

Skin Lesions

• Ulcer – Circumscribed, open sore or lesion of skin,

accompanied by inflammation

• Example: decubitus ulcer

• Vesicle – Small, thin-walled lesion containing clear fluid

• Example: blister

Skin Lesions

• Wheal – Circumscribed, slightly elevated lesion of the skin

– Paler in the center than the surrounding edges

• Example: hives

Question

Notice that sometimes 2 different terms

are used to describe the same thing. For

instance, if a physician says a patient

has hives, this patient also has

_______. a. comedos

b. papules

c. cysts

d. wheals

Answer

d. Wheals is the official medical term, and

hives is more of a “layman’s” term.

Question

A patient has a rash consisting of both

macules and papules. What would be

the combined adjective form? a. maculepapular

b. papulemacular

c. maculopapular

d. papumacular

Answer

c. Maculopapular is the correct combined

adjective form. Remember, the

combining vowel is used because the

second root begins with a consonant.

PATHOLOGICAL

CONDITIONS

Integumentary

System

Acne Vulgaris

• Pronounced – (ACK-nee vul-GAY-ris)

• Defined – Common inflammatory disorder seen on the face,

chest, back, and neck

– Appears as papules, pustules, and comedos

Albinism

• Pronounced – (AL-bin-izm)

• Defined – Condition characterized by the absence of pigment

in the skin, hair, and eyes

• Inherited condition

Burns

• Defined – Tissue injury produced by flame, heat, chemicals,

radiation, electricity, or gases

– Extent of damage determined by:

• Mode and duration of exposure

• Thermal intensity or temperature

• Anatomic site of the burn

Burns

• First-degree (superficial) burns – Example: sunburn

• Second-degree (partial-thickness) burns – Example: flash contact with hot objects, such as

boiling water

• Third-degree (full-thickness) burns – Example: deep burns from a fire

Callus

• Pronounced – (CAL-us)

• Defined – Common, usually painless thickening of the

epidermis at sites of external pressure or friction,

such as weight-bearing areas of the feet and on the

palmar surface of the hands

– Also known as a callosity

Question

True or False: The higher the degree

rating, the deeper the burn.

Answer

True. First-degree is superficial, while

third-degree is full thickness.

Carcinoma, Basal Cell

• Pronounced – (kar-sih-NOH-mah BAY-sal sell)

• Defined – A malignant epithelial cell tumor

– Begins as a slightly elevated nodule with a

depression or ulceration in the center

Carcinoma, Basal Cell

• Defined – As the depression enlarges, the tissue breaks

down, crusts, and bleeds

– Most common malignant tumor of epithelial tissue;

occurs most often on skin exposed to the sun

Carcinoma, Basal Cell

Image courtesy of Robert A. Silverman, M.D.,

Pediatric Dermatology, Georgetown University

Carcinoma, Squamous Cell

• Pronounced – (kar-sih-NOH-mah SKWAY-mus sell )

• Defined – Malignancy of the squamous, or scale-like, cells of

the epithelial tissue

– Much faster growing than basal cell carcinoma

– Greater potential for metastasis if not treated

Carcinoma, Squamous Cell

• Frequent sites on sun-exposed areas – Top of nose

– Forehead

– Margin of external ear

– Back of hands

– Lower lip

Carcinoma, Squamous Cell

Image Courtesy of Robert A. Silverman, M.D., Pediatric

Dermatology, Georgetown University

Dermatitis

• Pronounced – (der-mah-TYE-tis)

• Defined – Inflammation of skin, seen in several different forms

– Acute or chronic

– Contact or seborrheic

Eczema

• Pronounced – (EcK-zeh-mah)

• Defined – Acute or chronic inflammatory skin condition

characterized by erythema, papules, vesicles,

pustules, scales, crusts, scabs, and intense itching

Exanthematous Viral Diseases

• Pronounced – (eks-an-THEM-ah-tus VYE-ral dih-ZEEZ-ez)

• Defined – Skin eruption or rash accompanied by

inflammation, having specific diagnostic features of

an infectious viral disease

Exanthematous Viral Diseases

• Examples – Rubella = German measles

– Roseola infantum

– Rubeola = red measles

– Erythema infectiosum = fifth disease

Gangrene

• Pronounced – (GANG-green)

• Defined – Tissue death due to loss of adequate blood supply,

invasion of bacteria; subsequent decay of enzymes

produces foul odor

• Two forms – Dry

– Moist

Herpes Zoster

• Pronounced – (HER-peez ZOS-ter)

• Defined – Acute viral infection, characterized by painful,

vesicular eruptions on the skin that follow along

nerve pathways of underlying spinal or cranial

nerves

– Highest incidence in adults over 50

Herpes Zoster

Image courtesy of Robert A. Silverman, M.D.,

Pediatric Dermatology, Georgetown University

Hyperkeratosis

• Pronounced – (high-per-kerr-ah-TOH-sis)

• Defined – Overgrowth of the horny layer of the epidermis

– Occurs in psoriasis and in the formation of calluses

and corns

Impetigo

• Pronounced – (im-peh-TYE-goh)

• Defined – Contagious superficial skin infection characterized

by serous vesicles and pustules filled with millions

of staphylococcus or streptococcus bacteria

Question

This viral infection most commonly flares

up after age 50 and follows along nerve

pathways: a. eczema

b. rubeola

c. herpes zoster

d. impetigo

Answer

c. Also called “shingles.”

Kaposi’s Sarcoma

• Pronounced – (CAP-oh-seez sar-KOH-ma)

• Defined – Rare malignant lesions; begin as soft purple-brown

nodules or plaques on the feet

– Gradually spreads throughout the skin

– Increased incidence in men with AIDS

Keloid

• Pronounced – (KEE-loyd)

• Defined – Enlarged, irregularly shaped, elevated scar that

forms due to the presence of large amounts of

collagen during formation of a scar

Keratosis

• Pronounced – (kerr-ah-TOH-sis)

• Defined – Skin condition in which there is a thickening and

overgrowth of the cornified epithelium

Seborrheic Keratosis

• Pronounced – (seb-oh-REE-ik kerr-ah-TOH-sis)

• Defined – Brown or waxy yellow, wart like lesions that are

loosely attached to the skin surface

– Also known as seborrheic warts

Actinic Keratosis

• Pronounced – (ak-TIN-ic kerr-ah-TOH-sis)

• Defined – Premalignant, gray or red-to-brown, hardened

lesion caused by excessive exposure to sunlight

– Also known as solar keratosis

Leukoplakia

• Pronounced – (loo-koh-PLAY-kee-ah)

• Defined – White, hard, thickened patches firmly attached to

the mucous membrane, such as mouth, vulva, or

penis

Question

True or False: Keratosis literally means

condition of a horny-like growth in the

upper layer of skin, like a wart or callus.

Answer

True. This originates in the stratum

corneum, the uppermost layers of cells

with no nuclei and a plate-like

appearance.

Malignant Melanoma

• Pronounced – (mah-LIG-nant mel-ah-NOH-mah)

• Defined – Malignant skin tumor originating from melanocytes

in preexisting nevi, freckles, or skin with pigment

– Darkly pigmented tumor with irregular surfaces and

borders; variable colors

ABCDs of Malignant Melanomas

• Asymmetry

• Borders

• Color

• Diameter

Nevus

• Pronounced – (NEV-us)

• Defined – Visual accumulation of melanocytes, creating a flat

or raised, rounded macule or papule with definite

borders

– Commonly known as a mole

Question

Based on the definition of melanoma, what

is the actual meaning of melan-? a. dark pigment

b. light pigment

c. blue pigment

d. white pigment

Answer

a. Melanocyte is the cell that produces the

dark pigment (melanin) in our skin, hair,

and eyes. Albinism is the absence of this

pigment.

Onychocryptosis

• Pronounced – (on-ih-koh-krip-TOH-sis)

• Defined – Ingrown nail

• Most commonly involves the large toe

Onychomycosis

• Pronounced – (on-ih-koh-my-KOH-sis)

• Defined – Fungal infection of the nails

Pediculosis

• Pronounced – (pee-dik-you-LOH-sis)

• Defined – Highly contagious parasitic infestation caused by

blood-sucking lice

Pediculosis

• Pediculosis capitis – Head

• Pediculosis corporis – Body

• Pediculosis palpebrarum – Eyelashes and eyelids

• Pediculosis pubis – Pubic hair

Pemphigus

• Pronounced – (PEM-fih-gus)

• Defined – Rare, incurable disorder manifested by blisters in

the mouth and on the skin

– Spreads to involve large areas of the body

Pilonidal Cyst

• Pronounced – (pye-loh-NYE-dal SIST)

• Defined – Closed sac located in the sacrococcygeal area of

the back

– Sometimes noted at birth as a dimple

Psoriasis

• Pronounced – (soh-RYE-ah-sis)

• Defined – Common, noninfectious, chronic skin disorder

manifested by silvery-white scales over round,

raised, reddened plaques producing itching

(pruritus)

Psoriasis

Image courtesy of Robert A. Silverman, M.D.,

Pediatric Dermatology, Georgetown University

Rosacea

• Pronounced – (roh-ZAY-she-ah)

• Defined – Chronic inflammatory skin disease that mainly

affects the skin of the middle third of the face

– Characterized by persistent redness over areas of

the face, nose, and cheeks

Scabies

• Pronounced – (SKAY-beez)

• Defined – Highly contagious parasitic infestation caused by

the “human itch mite”

– Results in a rash, pruritus, and slightly raised

thread like skin lines

Scleroderma

• Pronounced – (sklair-oh-DER-mah)

• Defined – Gradual thickening of the dermis and swelling of

the hands and feet to a state in which the skin is

anchored to the underlying tissue

– No cure

Systemic Lupus Erythiematosus

• Pronounced – (sis-TEM-k LOO-pus air-ih-them-ah-TOH-sus)

• Defined – Chronic, multisystem inflammatory disease

characterized by lesions of the nervous system and

skin, renal problems, and vasculitis

– Characteristic “butterfly rash” is often seen on nose

and face

Tinea

• Pronounced – (TIN-ee-ah)

• Defined – Chronic fungal infection of the skin

– Characterized by scaling, itching, and sometimes

painful lesions

– Commonly known as ringworm

Tinea

• Tinea capitis – Scalp

• Tinea corporis – Body

• Tinea cruris – Groin

• Tinea pedis – Foot

Verruca

• Pronounced – (ver-ROO-kah)

• Defined – Benign, circumscribed, elevated skin lesion that

results from hypertrophy of the epidermis

– Commonly known as a wart

– Caused by the human papilloma virus

Verruca

• Verruca vulgaris – Common wart on face, elbow, fingers, or hands

• Plantar warts – Singly or in clusters on the sole of the foot

Verruca

• Venereal warts (condyloma acuminata) – Transmitted by sexual contact

• Seborrheic warts – Seen in the elderly on the face, neck, chest, or

upper back

– Benign

Question

Which condition is described as a highly

contagious parasitic disease caused by a

mite? a. verruca vulgaris

b. dermatitis

c. scabies

d. rosacea

Answer

c. The little mite, Sarcoptes scabiei,

burrows under the skin to lay eggs.

DIAGNOSTIC TECHNIQUES,

TREATMENTS, AND

PROCEDURES

Integumentary

System

Diagnostic Techniques, Treatments,

and Procedures

• Allergy testing – Various procedures used to identify specific

allergens in an individual by exposing the person to

a very small quantity of the allergen

• ImmunoCAP® Allergy Blood Test is more advanced,

convenient, and reliable

• Intradermal, patch, and scratch tests are common

• Cautery – Heat or caustic substances that burn and scar the

skin

Diagnostic Techniques, Treatments,

and Procedures

• Cryosurgery – Noninvasive treatment that uses subfreezing

temperature to freeze and destroy tissue

• Curettage and electrodesiccation – Scraping away of abnormal tissue, followed by

destroying the tumor base with a low-voltage

electrode

Diagnostic Techniques, Treatments,

and Procedures

• Debridement – Removal of debris, foreign objects, and damaged

or necrotic tissue from a wound to prevent infection

and promote healing

• Dermabrasion – Removal of the epidermis and a portion of the

dermis with sandpaper or brushes to eliminate the

superficial scars of unwanted tattoos

Diagnostic Techniques, Treatments,

and Procedures

• Dermatoplasty – Skin transplantation to a body surface damaged by

injury or disease

• Electrodesiccation – Technique using an electrical spark to burn and

destroy tissue

– Also known as fulguration

Diagnostic Techniques, Treatments,

and Procedures

• Electrosurgery – Removal or destruction of tissue with an electrical

current

• Escharotomy – Incision made into the necrotic tissue resulting from

a severe burn

Diagnostic Techniques, Treatments,

and Procedures

• Liposuction – Aspiration of fat through a suction cannula or

curette to alter the body contours

• Skin biopsy – Removal of a small piece of tissue from skin lesions

for examination under a microscope to confirm or

establish a diagnosis

Diagnostic Techniques, Treatments,

and Procedures

• Skin graft – Process of placing tissue on a recipient site, taken

from a donor site, in order to provide the protective

mechanisms of skin to an area unable to

regenerate skin

• Wood’s lamp – Ultraviolet light that is used to examine the scalp

and skin for the purpose of observing fungal spores

Question

True or False: Dermabrasion removes

debris or necrotic tissue and assists in

wound healing.

Answer

False. Debridement is for the removal of

debris, foreign objects, and damaged or

necrotic tissue. This assists in prevention

of infection and the promotion of healing

of the wound.