02-17 Psoriasis Flashcards
1. Know what is meant by the term “papulosquamous”. 2. Be able to name the features of the common papulosquamous disorders. 3. Be able to recognize the common papulosquamous disorders.
What is meant by the term “papulosquamous”?
lesion of scaly papules and plaques that literally means “bumpy and scaly”
—term to describe the lesions in the papulosquamous family
scale vs. crust?
“Scale” denotes an abnormally thick, flaky stratum corneum. “Crust” is synonymous with “scab” and denotes dried blood and serum.
Psorasis
- Prevalence?
- Presentation
- Triggers/Inheritance/Risk Factors
- Pathophys
- Path Findings
- Tx
- Assoc’d Conditions
Prevalence?
- Common - 3% of people will have an episode at some point in their lives
- Bimodal presentation: late 20s + early 50s
Presentation
- HAM: Dull, red, silver scale-y lesions on any cutaneous surface
- usu. extensor surf (elbows knees)
- sharp borders
- Commonly symmetric
- Pitting, oil spotting (looks yellow infraungal), and dystrophy of nails common
- Auspitz sign: pinpoint bleeding if picked b/c dilated caps and thin epiderm over dermal papillae
Triggers/Inheritance/Risk Factors
- Physical trauma (Koebner or isomorphic rxn): appearance after 10-14d; scars, areas of friction.
- Humid, temp, sunlight -
- Contact dermatitis, drug rashes
- Specific Rx aggravation: lithium, antimalarials, ß blockers, systemic (and~ topical) corticosteroid withdrawal, trazodone, terbinafine
- Infection: usually strep pharyng → acute guttate (drop-like) psoriasis; HIV
Pathophys
- Proliferation: mitoses above basal, shorter cell cycle, reduced cell transit time to surface
- Inflammation: vasodil → PMNs → microabscess Tx
Path Findings
- Acanthosis (thick epiderm) w/ regular elongation of rete ridges
- Hyperkeratosis w/ retention of nuclei in horny layer (parakeratosis)
- Munro microabscesses of PMNs high in epidermis
- Hypogranulosis
- Dilatation and tortuosity of capillaries
- Chronic dermis inflam
Tx (see other card)
- Topical
- Systemic
- Phototherapy
Assoc’d Conditions
- Arthritis
- 7% of psoriasis pts, usually s/p skin; usu oligoarticular, asymm, distal joints of hands/feet
- HLA B27 in up to 50%
- highest in those with spondylitis and mutilating distal disease
Variant Psoriasis Presentations
- a. Guttate: (drop-like), especially acute in children after strep, (superantigen driven?); tx infx to tx skin
- b. Pustular
- deep, dark brown spots with ham around
- (1) Localized, especially palms and soles
- (2) Generalized, with systemic symptoms
- c. Intertriginous “Inverse”: axilla, inframammary, gluteal cleft, post- auricular
- d. Erythrodermic: total body redness and scale, often with systemic symptoms; can become pustular
Risks of Psoriasis
- 50% increased mortality risk with severe psoriasis (5 years of life lost)
- Top causes of death among severe psoriatics
- # 1 CVD (34%) high output failure (perfusing all that skin)
- # 2 Infection (22%) usually opportunistic
- # 3 Cancer (21%)
- Th1/ Th17 inflammation
- Co-morbidities: embarrassment, genetics, diabetes, obesity, smoking, alcohol
Topical Psoriasis Tx
- Coal Tar (slows epidermal proliferation)
- Anthralin (stains)
- Topical steroids! – (most common, strength-site matched: thinning risk
- Calcipotriene/ calcipotriol (vitamin D)
- Tazarotene (retinoid)
Phototherapy Tx Options for Psoriasis
UVB Phototherapy
- Use 2 to 5x/week
- Takes several weeks!
- Risks: sunburn, activation of zoster , aging; skin cancer very unlikely
- Combinations increase efficacy: Coal tar, anthralin, tazarotene, and calcipotriene, Acitretin, Biologics
PUVA Phototherapy
- PUVA = Psoralens + Ultraviolet A (PUVA)
- Side effects:
- acute photoreactions & chronic photoaging
- Increased risk of SCC (with > 200 PUVA sessions)
- Probable increased risk of melanoma
- Can be used for maintenance
- Combination with acitretin more potent
List Systemic Rx Options for psoriasis
- MTX
- cyclosporine
- Acitretin
- Biologics
- Anti TNF-α
- Anti-T-cell
MTX
- Originally a chemotherapy drug
- Folate antagonist
- Slows fast-dividing cells
- Potential liver toxicity
- Effective for psoriatic arthritis
- Donʼt co-prescribe w/ Bactrim: myelosuppressive
Cyclosporine
- Originally an organ transplant drug
- Inhibits IL-2 production/ release
- Nephrotoxicity
- Irreversible loss of GFR w/in one year of use
- The FDA recommends continuous cyclosporine treatment be limited to one year at a time
Acitretin
- Similar to, but persists longer T1/2 than, isotretinoin
- Potentiates other treatment modalities!
- Synthetic retinoid
ADRs
- Teratogenic
- Potential liver toxicity
- Dose-dependent retinoid side effects include alopecia
- Start with low doses, increase if needed & tolerated
- Very limited drug interactions
- Follow LFT’s, triglycerides
- Gemfibrozil (Lopid) 3-600 mg BID, if needed
- Shouldn’t give blood after taking acitretin
Systemic Tx Options - BIOLOGICS
- Ustekinumab (Stelara)
- Hits P40 which stabilizes plaques → M.I.
- p40 = subunit of interleukin 12, a cytokine that acts on T and natural killer cells
- Anti-TNF-alpha
- Adalimumab (Humira)
- Etanercept (Enbrel)
- Infliximab (Remicade)
PASI
Psoriasis Area and Severity Index
- Way to score
- area of body
- severity: Erythema! • Thickness! • Scaling!
New Txs must score a particular score in order to be approved vs. most other FDA approval processes where you just have to show safety + better than placebo
Seborrheic Dermatitis in Adults
- Etiology
- Lesion appearance
- Distribution on body
- Natural Hx
- Common papulosquamous disorder
- Etiology related to Pityrosporum yeast
- Clinical presentations differ in adults vs. infants:
- Often scaly as air dries in winter
- Becomes red in the spring
- Body is responding to yeast or its waste products
- Moist, transparent to yellow, greasy scaling papules
- Distribution favors areas w/ high conc of seb glands (yeast eats sebum)
- scalp margins, central face and presternal areas
- eyebrows, the base of eyelashes, nasolabial folds and paranasal skin, and external ear canals
- Flexural skin may be similarly involve
- Adults tend to have a chronic course with remissions and exacerbations
Infantile Seborrheic Dermatitis
- Yellow greasy adherent scale “cradle cap” (“cradle crap”)!
- Minimal underlying redness!
- Scale may become thick and adherent! – Need to teach parents to remove it !
- Diaper area and axillary skin with redness > scaling!
- Usually a self-limited condition often not requiring treatment!