Psoriasis Flashcards
What is the pathophysiology of Psoriasis?
Multifactorial
Genetic - HLA and PSORS
Immunological: Abnormal T cell activity releases cytokines and stimulates keratinocyte proliferation
May be worsen by triggers eg, stress, strep, or improved by sunlight
What are the different types of psoriasis?
Plaque,
Guttate - triggered by strep throat
Pustular,
Erythrodermic
Flexural
Palmer/planter pustulosis
What are some exacerbating factors for psoriasis?
Trauma,
alcohol,
drugs (BALI: Beta blockers, Anti-malarials, Lithium, Indomethacin (NSAIDs) and infliximab)
and steroid withdrawal.
What are the nail changes that occur in psoriasis?
Pitting,
Onycholysis (nail becomes detached from underlying nail bed)
Subungual hyperkeratosis
What is the Koebner phenomenon?
Psoriasis at sites of trauma/scars. Not Auspitzs which is pin point bleeding that occurs with itching.
What does the following image show?
Guttate psoriasis. Small tear drop plaques of psoriasis. Can be triggered by a strptococcal infection 2-4 weeks before lesions appear.
Most resolve spontaneously within 2-3 months. Can use topical agents or UVB therapy
What does the following image show?
Erythrodermic psoriasis. It is a lot more inflammatory
What are the complications for psoriasis?
Psoriatic arthropathy,
Increased incidence of metabolic syndrome,
Increased risk of CV disease,
Increased incidence of VTE,
Psychological distress
What are the topical managements for plaque Psoriasis?
All - Emollient
1st line - Topical steroid (Betnovate) and topical vitamin D (Dovonex) at different times of day
2nd Line if no improvement after 8 weeks - Stop steroid and use vitamin D twice a day.
3rd Line if no improvement after 8-12 weeks- Stop vitamin D and apply potent steroid 2x day or coal tar.
Dithranol and tar are alternatives
What is the systemic treatment for Psoriasis?
1st line = Methotrexate,
2nd line = Ciclosporin (first line if palmoplantar or pregnancy),
3rd line = Acitretin.
Biologics - Infliximab, adalimumab, etranercept
What is the phototherapy used for psoriasis?
First line - Narrow ultraviolet B 3x week
Photochemotherapy can also be used (Psoralen UV A - PUVA)
what are the cautions with topical steroids?
Aim for 4 week break before starting another course.
Do not use potent steroids for > 8weeks and very potent > 4 weeks
Explain features of Vitamin D analogues in the treatment of psoriasis?
Works by reducing cell division and differentiation which reduced epidermal proliferation. They can be used long term and side effects are uncommon.
They reduce scale and thickness but not erythema
Avoid in pregnancy
Before and after use.
What are the side effects of methotrexate?
Pneumonitis
Hepatotoxicity (monitor LFTs)
Myelosupression which can lead to pancytopenia
What are the side effects of Acitretin?
Teratogenic and hepatotoxicity
