Seborrheic Dermatitis Flashcards
Disease characteristic
erythematous, scaly, pruritic patches and plaques with a yellowish, greasy appearance
where do rashes tend to develop?
scalp
similar to dandruff in what ways?
- both cause white/yellow scales
- both can be dry or greasy
- both can be itchy
how to differentiate it from dandruff?
- SD develops more than just scalp (ears, eyebrows, beard, skin around nostrils, chest)
- inflammed
extensive SD can develop in
- armpits
- belly button
- groin
- buttocks
- under breasts
pathophsiology
unknown, but:
1. disruption of microbiata
2. impaired immune reaction to malassezia spp. associated with diminished T-cell response
3. increased presence of unsaturated fatty acids on skin surface
4. disruptoin of cutaneous NTs
5. abnormal sheddingof keratinocytes
6. epiermal barrier disturbancesassociated with genetic factors
Malassezia species
lipophilic yeast genus part of the normal flora of skin; most prevalent fungal genus on skin fo rhumans; pathogenic if invades the stratum corneum
in SD, inflamatory reaction seems to be that irritant non-immunogenic stimulatoin of the immune system increases in what 2 cells?
NK+, CD16 activation
Cradle cap
occurs in 2-12 months of age, appears on the scalp, folds of skin, chest, back, and diaper area, and usually goes away on its own within months
Adolescence SD
goes away without treatment, but also possible to have the disease for life and experience flare-ups
adulthood SD
usually 30s or later, especially common in ≥50 years
disease flare-ups are typically seasonal, most being in ___ and disappearing in ___
most in winter, disappearing in warm, humid weather. also occurs when stressed
SD worldwide prevalence
5%
groups more likely to develop
- Black people
- men > women
- people with psoriasis/rosacea (called sebopsoriasis if psoriasis and SD)
- certain medications
6 medications that increase the risk for SD
- Aranofin
- Fluoruracil
- Griseoulvin
- Haloperidol
- Lithium
- Psoralen/PUVA
medical conditions causing higher susceptibility to SD
- neuro (PD, epilepsy)
2 HIV - brain/spinal cord accident
- lymphoma
- mood disorder
- down syndrome
- anorexia nervosa
- alcohol
- stroke/heart attack
- transplant (organ)
diagnosis
usually just examination, but may do a biopsy
if untreated, SD leads to
- thickening of scale
- secondary infection (candida)
- noticeable dark spots on skin patches (if darker skin tone)
Tx for scalp SD in infants (cradle cap)
- usually resolves when baby is 6-12 months
- baby shampoos with shea butter, glycerin, veggie oils, mechanical removal
- anti-inflammatory/antioxidant agents if not scalp
no evidence to support topical antifungals, anti-inflammatory, or keratolytics
Tx for scalp SD in adults and adolescents
- ketoconazole (shampoo, foam, gel, etc)
- alternatives: ciclopirox, miconazole, propylene glycol
severe Tx for scalp SD in adults and adolescents
- ketoconazole (shampoo, foam, gel, etc)
- alternatives: ciclopirox, miconazole, propylene glycol
plus a corticosteroid
duration for SD treatment in the scalp for adolescents and adults
3-4 weeks
Non-scalp Tx for SD in adults and adolescents
- topical antifungal + anti-inflammatory agents )ketoconazole, ciclopirox, clotrimazole, hydrocortisone, lithium/gluconate, pimecrolimus, tacrolimus)
- if severe/resistant
A: terbinafine
B: itraconazole
Roflumilast use in SD
hypothesized to be effective based on capacity to suppress proinflammatory cytokines implicated in SD by elevating cAMP
roflumilast vs crisaborole: PDE4i binding potency
rofl 25 x greater
roflumilast vs apremilast: PDE4i binding potency
rofl 300 x greater
when was Zoryve approved for SD?
12/2023; first drug with new MOA in over 20 years
which trial supported SD use?
- Phase 2 (Trial 203)
- Phase 3 (STRATUM)
