Integumentary System 5.4

Athlete’s Foot

Fungal infection often involving skin of the toes and soles

Impetigo

Bacterial infection common in young children

Candidiasis

Yeast infection mainly in moist areas

Eczema

Inflammation of the skin

Dandruff

Caused by a dry scalp producing flaking and itching

Urticaria (hives)

Allergic reaction causing reddish, elevated, and often itchy patches

Skin Cancer

Begins with mutation of the skin cell DNA

Nonmelanoma Cancers

Less likely to metastasize

Basal Cell Carcinoma

Most common type of cancer

Ultraviolet (UV) radiation causes epidermal basal cells to form a tumor

Signs are varied:

-Open sore that will not heal

-Smooth circular growth with a raised edge

-Shiny bump

-Pale mark

95% of patients are cures by removal of tumor

Squamous Cell Carcinoma

Much less common than basal cell carcinoma

More likely to spread than basal cell carcinoma; about 1% of cases result in death

Triggered by excessive UV exposure

Signs are the same as those for basal cell carcinoma, but may also resemble a wart or scaly growth that bleeds and scabs

Melanoma

More likely to be malignant

Starts in the melanocytes; looks like an unusual mole

Most common in fair-skinned persons who have experienced severe sunburn

Incidences have doubled in the last decade

Skin Cancer: Asymmetrical

Instead of being perfectly round, the mole has an oval or irregular shape

Borders of the mole are irregular and have notches or indentation in them

Color is uneven, and several colors may be present: black, brown, tan, red, or blue

Diameter of the mole is greater than 6 millimeters (larger than a pencil eraser)

Evolving

The mole has changed in size, shape or color

Prevention of Skin Cancer:

Use broad-spectrum sunscreens of at least SPF15

Wear protective clothing to cover skin

Wear UV sunglasses

Stay out of the sun between 10 a.m. and 3 p.m.

Avoid tanning machines

Kaposi’s Sarcoma

An opportunistic skin cancer found in AIDS and other immunocompromised patients

Moles and Warts

Moles and warts are not usually cancerous; moles are overgrowth of melanocytes and warts are caused by a virus

Wound Healing

Causes an inflammatory response: redness, swelling, heat and pain

Steps to wound healing

Blood fills the wound; a clot forms

White blood cells and fibroblasts move to the injured area

Fibroblasts pull the margins of the wound together and promote tissue regeneration

The basal layer of the epidermis produces new cells

Proliferating fibroblasts form a scar

Burns

Usually caused by heat, but also radioactive, chemical, and electrical agents

Two criteria used to determine severity of a burn: depth and the extent of the burned area

First Degree Burns

Only epidermis affected, Redness and pain, No blisters or swelling occurs

Second Degree Burn

Extends through entire epidermis and part of the dermis, and redness, pain and blistering (Second-degree burns cover 25% or more of the patients of the body)

Third Degree Burn

Also called full-thickness burns, destroys entire thickness of the skin, surface of wound is leathery and may be brown, tan, black, white, or red, patients feels no initial pain (Third-degree burns cover 10% or more of the patient’s body, occur on the face, hands, or feet)

Fourth Degree Burn

Involve tissues down to the bone (Any portion of the body has a fourth-degree burn)

Major concerns associated with severe burns

Fluid loss

Heat loss

Bacterial Infection