Psoriasis Flashcards
Types of psoriasis
1 - Psoriasis Vlugaris - Can be Early onset, in the 20s
(75%) or Late onset, in the 50s.
- subtypes:
1) Chronic, stable - the common form
2) Palmoplantar PV
3) Inverse (moist body folds)
4) Hairline or seborrheic psoriasis
5) Eruptive, inflammatory types
- Acute guttate type.
- Acute exudative
2 - Psoriatic erythroderma
3 - Pustular psoriasis
- subtypes
1) Acute generalized pustular psoriasis
2) Palmoplantar pustulosis
4 - Psoriatic Arthritis
Nail changes of psoriasis
Pitting
Subungual hyperkeratosis
Onycholysis
Oil spots - pathognomonic.
Treatment of psoriasis
Topical fluorinated glucocorticoids: Betamethasone valerate, Fluocinocole
PUVA phototherapy - Psoralen soak plus UVA.
MTX is 1st line for psoriasis larger than 10% of patients skin surface.
2nd line is cyclosporine and
Then biologics.
anti-TNF-alphas:
- Infliximab
- Etanercept
Ustekinumab
Secukinumab - IL-17 blocker
NEVER systemic glucocorticoids
Triggering factors for psoriasis
Physical trauma - Koebner phenomenon, rubbing scratching, cuts, surgery.
Infections - triggering guttate or actue exudative
Psychological stress
Drugs - beta blockers, glucocorticoids, antimalarials, lithium. These can exacerbate existing psoriasis, or cause psoriasiform drug eruption
Alcohol ingestion
HIV infection - Sudden psoriasis outbreak can indicate HIV
Histologic characteristics of psoriasis
Acanthosis
Hyperkeratosis
Parakeratosis
Extensive CD8 cell infiltrate, and less extensive CD4 cell infiltrate in the dermis and epidermis
Microabscesses of Munro in the stratum Corneum.
-formed by the lymphocyte and PMN cell infiltrates in the
Classic sites of psoriasis
Scalp - often pruritic, sebhorreic psoriasis
Elbows, fingers, fingernails
Perianal and genital regions - inverse psoriasis
Palms and soles
Pathogenesis of psoriasis
shortening of the keratinocyte cell cycle, accelerating it by about 28 times.
What is the pinpoint bleeding of psoriatic plaques called?
Auspitz sign.
Bleeding of the exposed capillaries in dermal papillae.
Pustular psoriasis morphology
pustules arising on normal or inflamed erythematous skin
Types of pustular psoriasis
Palmoplantar pustolosis
Acute Generalized Pustular psoriasis of von Zumbusch
Palmoplantar pustulosis
Chronic, remitting-relapsing eruption limited to the palms and soles
Sterile deep seated pustules that are puritic, and can be painful if they are large.
Evolve into dark red crusts.
Generalized acute pustular psoriasis of von zumbusch
Rare, life threatening psoriasis with abrupt onset.
Burning, firety red erthema with clusters of pinpoint sterile yellow pustules.
Spreads over the entire body within hours, and pustules coalesce to form very large lesions of pus that are easily ruptured and wiped off, leaving red oozing erosions.
Pustules form in repeated waves.
Systemic involvement: Fever, malaise, leukocytosis.
Very distressing, patient is usually quite fearful.
Onycholysis and hair loss is common 2-3 months later, as well as dequamation of the tongue.
Can follow or precede psoriasis vulgaris.
Psoriatic Arthritis
Seronegative spondyloarthropathy - arthritis lacking RF
Asymmetric peripheral joint involement
DOES involve the DIP joints, unlike RA. Often with the ‘pencil in cup’ deformity on XZ rya.
Dactylitis (thick sausage fingers)
Axial form involves vertebrae and sacroilliac
Associated with psoriatic nail deformities and psoriatic skin plaques.
Occurs in 5-8% of psoriatic patients.
Treatments for localized psoriasis
For any lesion with thick adherent scales, the scales should first be removed by 10% salicylic acid in mineral oil, wrapped in plastic overnight and the removed. Then the other therapy can begin.
Topical fluorinated glucocorticoid covered with
plastic wrap
Hydrocolloid dressing, left on for 24–48 h, is
effective and prevents scratching.
For small plaques (≤4 cm), triamcinolone acetonide
aqueous suspension 3 mg/mL diluted
with normal saline injected intradermally into
lesions.
Vitamin D analogues (calcipotriene, ointment
and cream) are good nonsteroidal antipsoriatic
topical agents but less effective than
corticosteroids; they are not associated with
cutaneous atrophy; can be combined with
corticosteroids.
Topical tacrolimus, 0.1%,
similarly effective.
Topical pimecrolimus, 1%, is effective in
inverse psoriasis and seborrheic dermatitislike
psoriasis of the face and ear canals.
Tazarotene (a topical retinoid, 0.05 and 0.1%
gel) has similar efficacy, best combined with
class II topical glucocorticoids.
All these topical treatments can be combined
with 311-nm UVB phototherapy or
PUVA.
Treatments for scalp psoriasis
Ketoconazole shampoo followed by 1% betamethasone valerate lotion.
