Alterations in Skin Function and Integrity

Agents Affecting Pathogenesis of Skin Disease
Sunlight
Insects and other arthropods
Infectious organisms
Chemicals
Physical agents
Rashes and Lesions
Rashes
Temporary eruptions of the skin
Childhood diseases, heat, diaper irritation, or drug-induced reactions
Lesion
A traumatic or pathologic loss of normal tissue continuity, structure, or function

Types of Rashes
Blanched (white)
Erythematous (reddened)
Hemorrhagic or purpuric (containing blood)
Pigmented
Types of Skin Lesions
Blister
Vesicle or fluid-filled papule
Callus
Hyperkeratotic plaque of skin due to chronic pressure or friction
Corns
Small, well-circumscribed, conical keratinous thickenings of the skin
Internal Disorders Causing Itching
Chronic renal disease
Diabetes
Biliary disease

Mediators Stimulating the Itch Receptors
Warmth, touch, and vibration act locally to trigger the itch phenomenon
Histamine, bradykinin, substance P, and bile salts act locally to stimulate the itch sensation
Prostaglandins are modulators of the itch response, lowering the threshold for other mediators
Atopic dermatitis appears to involve an immune-mediated release of cytokines and other pro-inflammatory mediators

Protection of Skin Related to Skin Color
Dark-skinned persons are better protected against:
Skin cancer
Premature wrinkling
Aging of the skin that occurs with sun exposure

Common Normal Variations in Dark Skin
Futcher (Voigt’s line)
Midline hypopigmentation
Nail pigmentation
Oral pigmentation
Palmar changes
Plantar changes
Appearance of Common Disorders of Black Skin
Hot-comb alopecia
Infantile acropustolosis
Keloids
Mongolian spot
Atopic dermatitis
Pityriasis rosea
Psoriasis
Tinea versicolor
Lichen planus
Effects of Ultraviolet Rays of Sunlight
Directly damaging skin cells
Accelerating the effect of aging on skin
Producing changes that predispose to development of skin cancer
Measures for Protection from the Sun
Avoidance of sun exposure
Use of protective clothing
Use of sunscreens
Types of Ultraviolet Rays
UVC rays
Short (100 to 289nm); do not pass through the earth’s atmosphere
UVB rays
290 to 320nm; Responsible for nearly all the skin effects of sunlight
UVA rays
321 to 400nm; can pass through window glass, are more commonly referred to as sun tanning rays

Photosensitivity Occurring with Drugs
Definition: exaggerated response to ultraviolet light when the drug is taken in combination with sun exposure
Examples
Some anti-infective agents
Antihistamines
Antipsychotic agents
Diuretics
Hypoglycemic agents
Non-steroidal anti-inflammatory drugs

C-H-E-S-S Acronym for Sun Protection
Clothing that is sun protective
Hats with wide brims all around
Eyeglasses that block UVA and UVB light
Sunscreen with an SPF of > 15 that is applied appropriately
Shade, especially between 10 AM and 4 PM
Types of Primary Skin Disorders
Pigmentary skin disorders
Infectious processes
Acne
Rosacea
Papulosquamous dermatoses
Allergic disorders and drug reactions
Arthropod infestations
Pigmentary Skin Disorders
Vitiligo
The sudden appearance of white patches on the skin
Albinism
A genetic disorder in which there is complete or partial congenital absence of pigment in the skin, hair, and eyes
Melasma
A disorder characterized by darkened macules on the face
Superficial Fungal Infections
Tinea of the Body or Face
Tinea of the Scalp
Tinea of the Foot and Hand
Tinea of the Nail
Tinea Versicolor
Tinea Incognito
Dermatophytid Reaction
Candidal Infections

Bacterial Infections
Impetigo
Verrucae
Herpes Zoster
Acne and Rosacea
Acne Vulgaris
Acne Conglobata
Factors Contributing to Acne
Influence of androgens on sebaceous cell activity
Increased proliferation of the keratinizing epidermal cells that form the sebaceous cells
Increased sebum production in relation to the severity of the disease
Decreased amounts of linoleic acid in the sebum
The presence of Propionibacterium acnes
Locations of Candidal Infections
Breasts, groin, axillae, anus, umbilicus, toes or fingerwebs
Vagina
Glans penis (balanitis)
Mouth (thrush)
Nails
Allergic and Hypersensitivity Dermatoses
Contact Dermatitis
Atopic and Nummular Eczema
Urticaria
Drug-induced Skin Eruptions
Papulosquamous Dermatoses
Psoriasis
Pityriasis rosea
Lichens planus
Lichens Simplex Chronicus
Arthropod Infestations
Scabies
Pediculosis
Ticks
Rocky mountain spotted fever
Lyme disease
Three Major Types of Skin Cancers
Malignant melanoma
Rapidly progressing malignant tumor of the melanocytes
Basal cell carcinoma
Neoplasm of the non-keratinizing cells of the basal layer of the epidermis; most common skin cancer in white-skinned people
Squamous cell carcinomas
Second most frequently occurring malignant tumors of the outer epidermis
Four Types of Melanomas
Superficial spreading
Nodular
Lentigo maligna
Acral lentiginous
Topical Agents to Treat Psoraisis
Emollients
Keratolytic agents
Coal tar products
Anthralin
Corticosteroids
Calcipotriene
Three Types of Lice Affecting Humans
Pediculus humanus corporis (body lice)
Phthirus pubis (pubic lice)
Pediculus humanus capitis (head lice)
Degrees of Burns
First-degree burns (superficial partial-thickness burns) involve only the outer layers of the epidermis
Second-degree partial-thickness burns involve the epidermis and various degrees of the dermis
Second-degree full-thickness burns involve the entire epidermis and dermis
Third-degree full-thickness burns extend into the subcutaneous tissue and may involve muscle and bone
Symptoms of Inhalation Injury
Hoarseness
Drooling
Inability to handle secretions
Rales
Rhonchi
Strider
Hacking cough
Labored and shallow breathing
Skin Manifestations of Infancy
Vascular and pigmented birthmarks
Diaper rash
Prickly heat
Cradle cap
Skin Manifestations of Common Infectious Disease
Roseola infantium
Rubella
Rubeola
Varicella
Scarlet fever
Skin Manifestations and Disorders in the Elderly
Skin tags
Keratoses
Lentigines
Vascular lesions