Infections and allergies

• Athlete's foot


  Caused by fungal infection (Tinea pedis)

  Itchy, red peeling skin between the toes

  
• Boils(furuncles) and carbuncles

  Caused by inflammation of hair follicles

  Carbuncles are clusters of boils caused by bacteria

  
• Cold sores (fever blisters)


  Caused by human herpesvirus 1

  Blisters itch and sting

  
• Contact dermatitis

  Caused by exposure to chemicals that provoke allergic responses

  Itching, redness, and swelling of the skin

  
• Impetigo

  Caused by bacterial infection

  Pink, fluid-filled raised lesions around mouth/nose

  
• Psoriasis


  Triggered by trauma, infection, hormonal changes, or stress

  Red, epidermal lesions covered with dry, silvery scales that itch, burn, crack, or sometimes bleed

  
• Burns


  Tissue damage and cell death caused by heat, electricity, UV radiation, or chemicals

  Associated Dangers:

  -Protein denaturation and cell death

  - Dehydration and electrolyte imbalance

  - Circulatory shock

  Results in loss of body fluids and infection from the invasion of bacteria

  
• Extent of a burn is estimated using the rule of nines


  Body is divided into 11 areas for quick estimation

  Each area represents about 9% of the total body surface area

  The area is surrounding the genitals(The perineum) represents 1% of the body surface area
• 1st degree burn (superficial burn)


  only epidermis is damaged, skin is red and swollen

  
• 2nd degree burn (superficial partial thickness burn)


  Epidermis and superficial part of dermis are damaged

  Skin is red, painful, and blistered

  Regrowth of the epithelium can occur

  
• 3rd degree burn (full thickness burn)

  Destroys epidermis and dermis; burned area is painless

  Requires skin grafts, as regeneration is not possible

  Burned area is blanched (gray-white) or black

  
• 4th degree burn (full thickness burn)

  Extends into deeper tissues (bone, muscle, tendons)

  Appears dry and leathery

  Requires surgery and grafting

  May require amputation

  
• Criteria for deeming burns critical (if anyone is met):

  Over 30% of body has 2nd degree burns

  Over 10% of the body has 3rd or 4th degree burns

  3rd or 4th degree burns of the face, hands , feet, or genitals

  Burns affects the airways

  Circumferential(around the body or limb) burns have occured
• Skin cancer

  Most common form of cancer in humans

  Most important risk factor is overexposure to ultraviolet (UV) radiation in sunlight and tanning beds

  
• Cancer can be classified two ways:

  1. BENIGN means the neoplasm (tumor) has not spread

  2. MALIGNANT means the neoplasm has invaded other body areas
• Most common types of skin cancer:

  basal cell carcinoma, squamous cell carcinoma, malignant melanoma

  
• Basal cell carcinoma


  Least malignant and most common type of skin cancer

  Arises from cells in stratum basale that are altered so that they can no longer make keratin

  Lesions appear as shiny, dome-shaped nodules that develop a central ulcer

  
• Squamous cell carcinoma

  Believed to be induced by UV exposure

  Arises from cells of stratum spinosum

  Lesions appear as scaly, reddened papules that gradually form shallow ulcers

  Early removal allows a good chance of cure

  Metastasizes to lymph nodes if not removed

  
• Malignant melanoma


  Most deadly of skin cancers, but accounts for only 5% of skin cancers

  Cancer of melanocytes

  Metastasizes rapidly to lymph and blood vessels

  Detection uses ABCD rule for recognizing melanoma

  
• A=Asymmetry

  two sides of pigmented mole do not match
• B= border irregularity


  borders of mole are not smooth
• C= Color


  different colors in pigmented area
• D=Diameter


  spot is larger than 6mm in diameter
• E= Evolution


  one or more of the ABCD characteristics is evolving