Psoriasis

Question 1

What is Psorasis?

Answer 1

• A chronic inflammatory skin disease due to hyperproliferation of keratinocytes and inflammatory cell infiltration

Question 2

What are the risk factors for Psorasis?

Answer 2

• 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

Question 3

What is the Pathophysiology of Psorasis?

Answer 3

• 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.

Question 4

What are the Associated Conditions with Psorasis?

Answer 4

• Psoriatic Arthritis
• Psoriatic Nails
• Other Conditions - more liked to have Inflammatory Bowel Disease, Metabolic Syndrome, CVS disease

Question 5

What are the Types of Psoriasis?

Answer 5

• 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

Question 6

How would you describe Psoriasis?

Answer 6

• 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

Question 7

What is Auspitz Sign?

Answer 7

• When the patient scratches and gently removes the scales this causes capillary bleeding

Question 8

What are the nail changes in Psoriasis?

Answer 8

• Pitting
• Onycholysis (lifting of the nail bed)
• Leukonychia (white discolouration)
• Subungual hyperkeratosis
• Splinter Haemorrhages
• Oil Drop Discolouration (yellow/pink patches)

Question 9

What is Psoriatic Arthropathy?

Answer 9

• Symmetrical Polyarthritis
• Asymmetrical oligomonoarthritis
• lone distal interphalangeal disease
• Psoriatic Spondylosis
• Arthritis Mutilans ( flexion deformity of distal interphalangeal joints

Question 10

What is the Managment for Psoriasis?

Answer 10

• General Measures
• Topical Therapies
• Phototherapy
• Oral Therapies

Question 11

What are some of the General Measures in the Managment of Psoriasis?

Answer 11

• Avoid Known precipitating factors
• Emollients - reduce scale

Question 12

What are some of the Topical Therapies in the Managment of Psoriasis?

Answer 12

• 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

Question 13

What is Phototherapy in the Managment of Psoriasis?

Answer 13

• 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)

Question 14

What are some of the Systemic Treatments for Psoriasis?

Answer 14

• Methotrextate
• Ciclosporin
• Acitretin
• Biologics

Question 15

How does Methotrexate work?

Answer 15

• Antifolate immunosuppresent
• Reduces the hyperproliferation of keratinocytes
• Tetraogenic - not for pregnancy or breastfeeding
• Contraception advised

Question 16

How does Ciclosporin work?

Answer 16

• Calcineurin inhibitor with immunosuppressant action
• Used in an acute flare
• In palmoplantar pustulosis
• When patients are considering pregnancy

Question 17

How does Acitretin work?

Answer 17

• It is a retinoid
• for when other options have failed

Question 18

How does Biologics work?

Answer 18

• Infliximab
• Monoclonal Antibodies that modulate the immune system
• Administered as IV injections and generally reserved for severe and treatment-resistant disease

Question 19

What are some of the Complications of Psoriasis?

Answer 19

• 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

Question 20

What is the step-wise managment for Chronic plaque psoriasis?

Answer 20

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

Question 21

What is the managment for Scalp Psoriasis?

Answer 21

• Potent topical corticosteroids used once daily for 4 weeks

Question 22

What is the managment for Face, Flexural and Genital Psoriasis?

Answer 22

• Mild to moderate potency corticosteroid applied once/ twice daily for max 2 weeks

Question 23

How does Vit D analogue work?

Answer 23

• 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