Ch. 34 - Scaly Dermatoses Flashcards
1
Q
Scaly Dermatoses
A
- Chronic Dermatoses: dandruff, sehorrheic dermatitis (SD), and psoriasis
- Involve uppermost skin layer: epidermis
- Dandruff - less inflammatory form with fine scaling limited to scalp
- SD - involves dace, scalp, and chest with significant inflammation
- Psoriasis - highly inflammatory skin condition with raised plaques and adherent thick scales, profound physical, psychological, and economic consequences
- Non-Rx usually good for dandruff and SD
- Mild psoriasis may respond to non-Rx, but initial diagnosis and management of flares requires a dermatologist
2
Q
Dandruff
A
- Chronic, mildly inflammatory scalp disorder
- Character: excessive scaling
- Cosmetic concern with social stigma
- Less inflammatory end of SD
- Not sure if inadequate shampooing makes it worse, but consistent washing is important with this condition
- 1-3% prevalent in population
- Uncommon in children, usually occurs in puberty and reaches peak in early adulthood
- Levels off at middle age and drops off in elderly
- No gender preference and bald spots are usually dandruff free
- Also less severe in summer
- Malassezia (Mala.) species agreed to cause accelerated cell turnover and inflammation seen in both dandruff and SD
3
Q
Dandruff Pathophysiology
A
- Hyperproliferative epidermal disorder
- Accelerated cell turnover (2x), irregular keratin breakup pattern causing shedding of large, nonadherent white scales
- Crevices occur deep in strum corneum causing cracking and the large scale generation
- If broken down to smaller units the dandruff becomes less visible
- Thought to be due to irritant inflammatory effects of fatty acids and cytokines produced by Mala
4
Q
Dandruff Presentation
A
- Diffuse, minimally inflammatory
- Scaling is the only visible part, large white or gray scales
- Pruritus is common as well
- Crown of head often prime location
5
Q
Dandruff Treatment Goals
A
- Decrease epidermal turnover rate by decreasing Mala
- Minimize cosmetic embarrassment of visible scaling
- Minimize itch
6
Q
Dandruff General Treatment
A
- Washing with general purpose, non-medicated shampoo daily or every other day
- If not effective, can provide non-Rx medicated dandruff shampoo
- Massage shampoo into scalp and leave in for 3-5 minutes before rinsing
- If shampoo contains selenium, additional rinsing is suggested since it can discolor especially light hair
- Medicated shampoos should be used daily for a week, then 2-3 times a week for 2-3 weeks, and then once weekly or every other week to control condition
- Scalp scrubbers help ensure adequate contact with scalp especially with long hair
- An agent that decreases Mala. is recommended initially or a non-Rx ketoconazole with anti-Mala. activity can be useful
- Shampoos containing cytostatic agents are second line therapy with limited efficacy and potential to discolor
- Keratolytic shampoos containing salicyclic acid or sulfur may also be used but need longer treatment periods for efficacy
- If resistant after 4-8 weeks of use, refer to PCP to get a high concentration of selenium sulfide or ketoconazole
7
Q
Seborrheic Dermatitis (SD)
A
- Subacute or chronic inflammatory disorder occuring mainly from areas of greatest sebaceous gland activity
- Chronic red, scaly, itchy rash typically seen within first 3 months of like and in the fourth to seventh decades
- Common in infants and 2-5% of adults
- Typically more severe in winter, may also be aggravated by emotional stress
8
Q
SD Pathophysiology
A
- More inflammatory than dandruff and marked by accelerated epidermal proliferation in areas with dense distribution of sebaceous glands from increased Mala levels
- 9-10 days for SD cell turnover rates (13-15 in dandruff, 25-30 for normal)
- Accelerated cell turnover, enhanced sebaceous gland activity, prominent yellow greasy scales
9
Q
SD Presentation
A
- Scalp, eyebrows, glabella eyelif margins, cheeks, paranasal areas, central back, nasolabial folds, head area, presternal area, retroauricular creases, in and around external ear canal
- Typically presents as dull, yellowish, oily, scaly areas on red skin
- Pruritis is common
- Infantile form: greasy scales and scale crusts on bright erythematous base on scalp, lateral neck, and areas mentioned earlier
- Usually clears in 8-12 months and doesn’t resurface until puberty
- Adult form: yellow, greasy scales on scalp and extended to middle third of face with eyebrow involvement
- Frequently seen with Parkinson’s patients
- Lasts years to decades with improvements in warmer season and exacerbations in cold
10
Q
Adult Form + Presentation Areas
A
- Scalp: Greasy, scaling patches or plaques, exudation, and thick crusting
- Face: Flaky scales or yellowish scaling patches on red, itchy skin in eyebrows/glabella
- Ear canals, aud. meatus, and postauricular areas: red scaling, fissures, swelling
- Chest and Back: V-shaped areas
11
Q
SD Treatment Goals
A
- Decrease inflammation and cell turnover from Mala
- Minimize or eliminate visible erythema/scaling
- Minimize itch
12
Q
SD General Treatment
A
- Similar to dandruff but more aggressive due to inflammation
- Therapy controls but doesn’t cure
- Aims to loosen and remove scales/crusts, inhibit yeast colonization, control secondary infection, and decrease erythema/itching
- Same shampoo recommendations except use it 2-3 times a week for FOUR weeks after first week of use
- In infants, usually self limiting and can be treated by massaging scalp with baby oil and using unmedicated shampoo
- Refer to pediatrician if these methods don’t work
- In adults, shampooing is the foundation of treatment and can be applied to the face and body
- Can use cosmetically acceptable shampoo afterwards if smell is objectable
- Can use topical corticosteroids for inflammation and erythema post-shampoo
- Hydrocortisone can be used no more than twice daily due to a reservoir effect
- Don’t use non-Rx hydrocortisone for more than 7 days in a row
- Refer to doctor if SD worsens or persists after 7 days
13
Q
Psoriasis
A
- Chronic inflammatory disease effecting 1-3% of Americans
- Lesions usually local, but can be general too
- Remissions/exacerbations are unpredictable
- Can cause enough psychological distress to effect the quality of life
- Moderate to severe forms can also cause significant physical and economic burdens
- Equal effects men and women
- All races and geographical areas but shown to have lower instances closer to the equator
- Cause is unknown
- Exacerbation factors: environment, infections, drug use, psychological stress, endocrine/hormone changes, obesity, alcohol and tobacco use
14
Q
Psoriasis Pathophysiology
A
- Accelerated cell turn over causing excessive scaling on raised plaques, turnover is about 4 days
- Lesions lasts lifetimes or disappear quickly
- Can leave skin hypo or hyperpigmented after lesion fades
- Tends to be chronic and relapsing with spontaneous exacerbations/remissions
15
Q
Psoriasis Clinical Presentation
A
- Usually symmetrical
- Plaque is most common symptom (90%)
- Start as small papules that grow and unit to form plaques
- Lesions are well-circumscribed, shaply demarcated, light pink/bright red/maroon, overlying opaque, thick, adherent white scales that can be pulled off in layers
- Punctate bleeding points can occur when scales are removed
- Common locations: elbows, knees, lumbar region, scalp, posterior auricular areas, external auditory canal, and glans penis
