Flat, colored lesion < 2 cm in diameter
Large macular lesion > 2 cm
Minute hemorrhagic spots in the skin
Purplish patch caused by extravasation of blood to the skin--essentially large petechiae
Dilated, superficial blood vessels (i.e. spider veins)
Small, solid lesion < 1 cm in diameter
Large papular lesion (1-5 cm)
Flat-topped raised lesion > 1 cm in diameter; edges may be distinct (i.e. psoriasis) or gradual (i.e. eczema)
Solid, raised growth > 5 cm in diameter
Raised, erythematous papule or plaque, usually related to short-term derma edema
Small, fluid filled lesion < 1 cm in diameter
Larger vesicular lesion, > 1 cm in diameter (i.e. blister)
Vesicle filled with leukocytes; puss filled or filled with purulent materials
Soft, raised, encapsulated lesion filled with semisolid or liquid contents
Dried exudates of body fluids (usually red or yellow)
Small, thin plate o fhorny epithelium, cast off from the skin
Leather, thickening of the skin characterized by hyperkeratosis
Any loss of skin "substance"
Loss of epidermis without associated loss of dermis
Linear, angular erosions (may be covered by scratching)
A deep furrow, cleft, or slit
Loss of epidermis and at least a portion of the underlying dermis
The order of vehicles in order of moisturizing to drying: W/O emulsions, oil-free emulsions with emollient esters, alcohol solutions, oleaginous bases, strictly oil-free emulsions, and O/W emulsions
- Oleaginous bases
- W/O emulsions
- O/W emulsions
- Oil-free emulsions with emollient esters
- Strictly oil-free emulsions
- Alcohol solutions
Describe oleaginous or water-free products
- semisolid= ointments
- liquid= oils
- barrier-like product that is moisturizing
- generally very greasy
- Prevents water loss and creates moisturizing properties
Describe absorption bases
- Water free products + lanolin or cholesterol
- Slightly less greasy and less moisturizing
- Hydrophobic and hydrophilic end
- Allows the dispersion of two immiscible compounds
What is the name of a cream or lotion in which the "external" phase is oil? What type of skin is it recommended for?
- W/O emulsions
- Less greasy that water free products but still strong moisturizers
- Moderately dry skin
What is the name of a cream or lotion in which the "external" phase is water? What type of skin should it be used on?
- O/W emulsions
- Less greasy than W/O preparations
- Mild moisturizers that are designed for normal or slightly dry skin
Describe Oil Free products
- Strictly oil free: drying bases used for oily skin
- Borderline oil-free: contain emollient esters
- Oil free products that have a drying effect due to evaporation of solvent
- Water soln= mildly drying
- Alcohol soln= very drying
What is a clear, non-oily solid composed of long-chain molecules and a small amount of solvent?
- Mildly drying and useful for oily to normal skin types
Are ointments or creams more potent?
Ointments--due to occlusive effect
What is a humectant?
- Non-oily ingredient designed to help the skin retain water
- Shifts an existing product to be more moisturizing
Which was does powder shift a product: more drying or more wetting?
What is the M.O.A. of topical corticosteroids?
- Inhibition of transcritpion factors involved in the activation of pro-inflammatory genes.
- Suppression of arachidonic acid release from phospholipids
- Inhibit leukocyte migration to sites of inflammation
- Interfere witht he functions of endothelial cells, granulocytes, mast cells and fibroblasts.
How do topical steroids help on inflamed skin?
Inhibit migration of macrophages and leukocytes into the area by reversing vascular dilation and permeability
How often should topical steroids be applied? Duration?
What increases the absorption of topical corticosteroids?
- Increased skin temperatures
- Application to inflamed or denuded skin
- Intertriginous areas
- Skin surfaces with a thin stratum corneum layer
What are common side effects of topical corticosteroids?
- Burning, itching, irritation, erythema, dryness
- Skin atrophy -- decreases the thickness of the epidermis
- Ocular hypertension, glaucoma, cataracts
- Worsening of cutaneous infections
What can occur if topical corticosteroids are used after skin atrophy?
- Prolonged therapy can decrease barrier function of the skin
- Vascular dilatation-- striae, telangiectasia, purpura
What is it called when an itch originates in the skin from skin damage (i.e. inflammation, dryness)
What is it called with an itch originates froma lesion or abnormality at some point in the afferent neuronal pathway?
- Neuropathic itch
- example: shingles
What is an itch that originates from a central mechanism but without obvious neural pathology?
- Example: opioid induced itch
What is a psychogenic itch?
Delusional in nature
What is the primary mediator of itching?
Describe the pathophysiology of an itch
- Cross talk between dermal mast cells and afferent C neuron terminals
- Scratching and rubbing the skin inhibits itch by stimulating myelinated A neurons
- Termpoarirly inhibit neuronal circuits involved with itch
- Also activates nociceptors --> reduce itch via the spine
- Pain inhibits itch
What symptoms appear if pruritus is histamine induced?
wheal and flare
What is the first and second line treatment for treating pruritus?
- 1st: H1 antihistamines
- 2nd: Topical corticosteroids--> relieve itching secondary to inflammatory skin disease
In what patients can cholestyramine be used to relieve itch?
Patients who have generalized itching and renal failure
What desensitizes nociceptive nerve endings and acts as a antipruritic? Use is limited by tolerability
What is a potent antihistamine and effective antiprutitic limited by it's anticholinergic side effects?
Rash characterized by wheals with or without angioedema. Spectrum of superficial pink wheals that itch to angioedema of the subcutaneous and submucosal tissues
How are most symptoms of urticaria mediated?
Via H1 receptors on nerves and endothelial cells
What type of urticria has wheals present for most days and can be due to drugs, food, and viral infections? Duration < 6 weeks
In what patient population is acute urticaria more prevalent?
Patients with atopic diseases
Describe chronic urticaria
- > 6 weeks duration
- Wheals present daily or most days
- Symptoms may be continuous or recurrent
- diet, infection, and non-infectious chronic inflammatory disorders have been implicated
What type of physical urticaria is due to shearing forces?
What type of physical urticaria is due to vertical pressure?
Delayed pressure urticaria
What type of physical urticaria is due to cold air, water, or wind?
Cold contact urticaria
What type of physical urticaria is due to localized heat?
Heat contact urticaria
What type of urticaria is due to brief increases in body core temperature?
MOA of H1 antagonists
- Decreased capillary permeability
- Decreases histamine mediated exocrine secretions
Narrow angle glaucoma, stenosing peptic ulcers, and symptomatic BPH are contraindications to what drugs?
1st generation antihistamines
What are some warnings for antihistamine medications?
- COPD, asthma
- Anticholinergic (drying effects)
What is xerosis?
Dehydration of the stratum corneum
What part of the body does xerosis most affect?
Lower extremities and forearms
Describe the appearance of xerosis.
- Skin covered in dry scales
- More severe can cause cracks, fissures, decreased suppleness
What are preventative measures that can be taken for xerosis?
- Low room temperature
- Use of a humidifier
- Bathing in warm, not hot water, no more than every 1-2 days
- Reduce excessive exposure to soap, solvents, and other drying agents
- Use emollients frequently
How do you treat xerosis?
- Soak affected area 5-10 minutes and then immediately apply W/O type of medication
- Topical corticosteroid ointment may be used for symptoms especially associated with eczema