Psoriasis Flashcards
What is Psorasis?
- A chronic inflammatory skin disease due to hyperproliferation of keratinocytes and inflammatory cell infiltration
What are the risk factors for Psorasis?
- Genetics
- Streptococcal infection ( related to Guttate psorasis)
- Trauma ( Koebner Phenomenon - new lesions of a pre-existing dermatosis occur at sites of skin trauma - red line joining the dots)
- Hormones (worse in puberty, menopause and postpartum period)
- Drugs (Beta-blockers, Lithium, Chloroquine and Ace-inhibitors and NSAIDs)
- HIV
- Smoking
- Alcohol
- Stress
What is the Pathophysiology of Psorasis?
- Psoriasis is an immune- mediated disease featuring hyperproliferation of the epidermis
- There is release of inflammatory mediators and dendtritic cells are activated producing IL-23 triggering T cell involvement.
What are the Associated Conditions with Psorasis?
- Psoriatic Arthritis
- Psoriatic Nails
- Other Conditions - more liked to have Inflammatory Bowel Disease, Metabolic Syndrome, CVS disease
What are the Types of Psoriasis?
- Chronic Plaque Psoriasis
- Guttate Psoriasis - raindrop psoriasis, occurs after a streptococcal sore throat infection, self-limiting within 3/4 weeks
- Erythrodermic Psoriasis - widespread erythema and psoriasis, triggers: recent illness, medications and emotional stress. Can be life-threatening. Immunosuppressive agents and biologics should be used.
- Localised Pustular Psoriasis - Affects hands and feet, pustules and plaques, associated with smoking
- Generalised Pustular Psoriasis - rapidly developing, widespread erythema and pustules. Pustules coming together and form lakes of pus, resolve over days leaving erythema and scaring - dermatological emergency
- Seborrhoeic Psoriasis
- Flexural Psoriasis
How would you describe Psoriasis?
- A well-demarcated erythematous scaly plaques
- Lesions can be itchy, burning or painful
- Common on extensor surfaces of the body and over the scalp
- Auspitz Sign
- Nail Changes
- Psoriatic Arthropathy
What is Auspitz Sign?
- When the patient scratches and gently removes the scales this causes capillary bleeding
What are the nail changes in Psoriasis?
- Pitting
- Onycholysis (lifting of the nail bed)
- Leukonychia (white discolouration)
- Subungual hyperkeratosis
- Splinter Haemorrhages
- Oil Drop Discolouration (yellow/pink patches)
What is Psoriatic Arthropathy?
- Symmetrical Polyarthritis
- Asymmetrical oligomonoarthritis
- lone distal interphalangeal disease
- Psoriatic Spondylosis
- Arthritis Mutilans ( flexion deformity of distal interphalangeal joints
What is the Managment for Psoriasis?
- General Measures
- Topical Therapies
- Phototherapy
- Oral Therapies
What are some of the General Measures in the Managment of Psoriasis?
- Avoid Known precipitating factors
- Emollients - reduce scale
What are some of the Topical Therapies in the Managment of Psoriasis?
- Emollients - moisturising agents that reduce itching and remove scaling
- Topical Steroids - beclometasone - have an anti-inflammatory effect and used for a limited defined courses.
- Vit D analogues - Calcipotriol, modulates the immune system and reduces hyperkeratosis. Can be used as a long-term treatment option. Care to avoid hypercalcaemia, pregnancy and breast-feeding
- Vit A analogues - Tazarotene - used sparingly, causes irritation. Contraindicated in pregnancy and breast-feeding.
- Tar preparations - reduce scaling and slow plaque formation down, comes in shampoo, creams and ointments
- Short contact dithranol - used for short periods of times before being rinsed off (10-30mins), applied to chronic extensor plaque lesions only
What is Phototherapy in the Managment of Psoriasis?
- UVB: Narrow-band ultraviolet B therapy may be used in patients with plaque psoriasis that has not adequately responded to topical therapy
- PUVA: Form of Photochemotherapy which uses a combination of a photosensitising drug and UV therapy (Psoralen and UV therapy)
What are some of the Systemic Treatments for Psoriasis?
- Methotrextate
- Ciclosporin
- Acitretin
- Biologics
How does Methotrexate work?
- Antifolate immunosuppresent
- Reduces the hyperproliferation of keratinocytes
- Tetraogenic - not for pregnancy or breastfeeding
- Contraception advised
How does Ciclosporin work?
- Calcineurin inhibitor with immunosuppressant action
- Used in an acute flare
- In palmoplantar pustulosis
- When patients are considering pregnancy
How does Acitretin work?
- It is a retinoid
- for when other options have failed
How does Biologics work?
- Infliximab
- Monoclonal Antibodies that modulate the immune system
- Administered as IV injections and generally reserved for severe and treatment-resistant disease
What are some of the Complications of Psoriasis?
- Psychological - affect confidence and induce mental illness
- Systemic Upset - erythrodermic psoriasis and generalised pustular psoriasis can lead to significant systemic upset
- Medication-Related - skin irritation, teratogenicity and malignancies
What is the step-wise managment for Chronic plaque psoriasis?
1st line:
- potent corticosteroid applied once daily + Vitamin D analogue
- one in the morning and one in the evening
- 4 weeks initial treatment
2nd line:
- if no treatment after 8 weeks
- a Vit D analogue twice daily
3rd line:
- if no improvement after 8-12 weeks then offer:
- a potent corticosteroid applied twice daily for 4 weeks
- a coal tar preparation applied once or twice daily
- a short-acting dithranol
What is the managment for Scalp Psoriasis?
- Potent topical corticosteroids used once daily for 4 weeks
What is the managment for Face, Flexural and Genital Psoriasis?
- Mild to moderate potency corticosteroid applied once/ twice daily for max 2 weeks
How does Vit D analogue work?
- They decrease cell division and differentiation and therefore decrease epidermal proliferation
- May be used long term
- They reduce the scale and thickness of the plaques but not the er
