dermatology Flashcards
this is a vital organ; one of the largest in our human body with a surface area of about 1.8m^2. consists of the outer epidermis and the inner dermis
skin
this layer of skin primarily provides protection from the environment and performs a critical barrier function - keeping water and other vital substances in and foreign substances out
epidermis
this layer of skin is a connective tissue layer with primarily provides resiliency and support for various skin structures or appendages as well as sweat glands, sebaceous glands, hair and nails; contains collagen and elastin
dermis
subcutaneous tissue lies beneath the epidermis or the dermis?
dermis
what are the five stratum layers that make up the epidermis?
stratum corneum (horny layer)
stratum lucidity
straum granulosum (granular layer)
stratum spinosum (prickle cell layer)
stratum basale (where keratinocytes (skin cells) are made)
these are also known as skin cells; they produce keratin and forms the physical protective barrier
keratinocytes
these cells produce melanin and provides UV protection
melanocytes
this type of sweat gland flows out of the hair shaft
apocrine sweat gland
this type of sweat gland flows out through its own sweat pore
eccrine sweat gland
what are the functions of the skin?
- protects the body against injury, physical agents, and UV radiation
- regulates body temperature
- prevents dehydration thus helping to maintain fluid balance
- acts as a sense organ (e.g. touch, pain, heat and cold)
- acts as an outpost for immune surveillance
- has a role in vitamin D production and absorption
skin hydration is usually 10-20% water by weight. What may happen if the skins hydration drops below 10%?
- stratum corneous becomes brittle and may crack easily
- allows irritants to penetrate skin which may lead to mild inflammation and impaired cell maturation which may result in chapping
barrier efficiency generally begins to regenerate within __ hours of skin damage.
24
true/false: when skin is damaged, the skin forms a temporary barrier of parakeratotic cells and dried exudate
true
what factors can decrease skin hydration/contribute to dry skin?
- extremes of temp
- aging
- physical trauma
- chemical irrigation/trauma
- medications
- other medical conditions
what are some physiological changes in aging skin?
- thinning epidermis (fewer active basal cells in epidermis)
- slower healing (slower cell turnover)
- delayed inflammatory response (fewer langerhan cells)
- reduced tactile sensitivity (reduced acuity of pain perception)
this is known as inflammation of the skin; an acute or chronic skin reaction with corresponding clinical patterns and history
dermatitis
this is a common condition in infants an diaper wearing incontinent elderly nursing home residents
diaper dermatitis
what are some risk factors for diaper rash?
- moisture retention
- friction and contact irritation
- urine and ammonia (ammonia does not cause diaper rash but aggravates it, especially if the skin is broken)
- feces and alkaline ph (may cause skin to lose barrier function)
- some foods may increase urine ph (high protein diets0
- vigorous cleansing
- psoriasis
- immobility
what are some drugs that may contribute to drug-induced diaper dermatitis?
- penicillins
- sulfonamides
- topical antihistamines
- lanolin
this fungal microorganism is the most frequent cause of diaper rash. Requires drug tx
candida albicans
this bacterial microorganism is a frequent colonizer of dermatitic skin. occasionally causes severely inflamed dermatitis with follicular pustules. requires drug tx
staph aureus
what are the goals of therapy of diaper dermatitis?
- relief of symptoms
- resolution of diaper dermatitis
- prevent reoccurrence
- provide cost-effective therapy
- minimize adverse reactions from therapy
- prevent complications (untreated/infected dermatitis, which can lead to ulcerations, UTIs, infection of penis/vulva, etc)
explain the clinical presentation of diaper dermatitis.
- found in the diaper area (rash generally spares inguinal skin folds, except for candida diaper rashes)
- erythemateous rash, often with shiny patches over convex surfaces of diaper rash (may appear dusky purple on darker skin)
- severe rashes: may have vesicles, may have oozing and widespread erosions
explain the clinical presentation of candida diaper rash.
- early maceration of anal mucosa and perianal skin
- confluent tomato red plaques, papules, pustules
- culture will be positive for candida
- almost always involves the inguinal folds
