Psoriasis Flashcards
What is psoriasis?
an inflammatory skin disorder
where you get an increased turnover of the skin
due to an increase in keratinocyte proliferation
What is the classical morphology in psoriasis?
Red scaly plaques
on extensor surfaces and scalp
How long does psoriasis usually last?
It has chronic relapsing course that usually lasts the lifetime of the pt
Is psoriasis normally biopsied?
No as the Dx is normally clinically evident
What are the 6 types of psoriasis?
Chronic plaque psoriasis (most common)
Palmo-plantar psoriasis
Flexural psoriasis
Guttate psoriasis
Erythrodermic psoriasis
Pustular psoriasis subtypes:
1) Palmoplantar
2) Generalised
What nail changes are associated with psoriasis?
Pitting
Onycholysis
Subungal hyperkeratosis
What is onycholysis?
When the distal end of the nail seems to be lifting up from the nail bed
What is subungal hyperkeratosis?
when there is a lot of keratin debris underneath the distal end of the nail
In which age groups is guttate psoriasis more common?
Children and adolescents
What is the course of guttate psoriasis?
tends to resolve by itself
over several months but
sometimes can persist for much longer
What are the common causes of erythroderma?
eczema
drug reactions
(erythroderma caused by psoriasis is fairly rare + will usually precede the erythroderma)
Why can erythrodermic psoriasis be hard to diagnose?
As it may not have the red scalyness of the plaques.
It is unlikely however to present as the pts first experience of psoriasis
What other symptoms is a pt likely to have with erythrodermic psoriasis and why?
Systemically unwell as the inflamed skin causes loss of:
heat,
protein and
fluid
What is the commoner variety of pustular psoriasis?
Palmoplantar pustular psoriasis
Who does palmoplantar pustular psoriasis occur more in, M or F?
females more often get palmoplantar pustular psoriasis
What risk factor is palmoplantar pustular psoriasis associated with?
Smoking
What normally precedes generalized pustular psoriasis?
Chronic plaque psoriasis
Which two types of psoriasis are commonly associated with being systemically unwell?
erythrodermic psoriasis
and
generalized pustular psoriasis
What are the systemic complications of severe psoriasis?
psoriatic arthritis (10%)
What age group is psoriatic arthritis most common in?
40-60 yr olds
What are the types of psoriatic arthritis?
mono-articular -> affects 1 or 2 large joints
the distal interphalangeal joints
arthritis mutilans -> all the small joints of the hands affected
Give some aggravating factors for psoriasis?
Streptococcal throat infections
beta blockers
lithium
antimalarials
stress
alcohol + smoking
What usually makes psoriasis better?
Sunlight
What are the four steps of psoriasis management?
1st line - education
1st line - topical treatment
2nd line - phototherapy
3rd line - systemic treatment
(4th line - biological agents)
Can psoriasis be “cured”?
No
What are the first line topical therapies for psoriasis? (with examples)
Emollients (E45)
Vitamin D3 analogues (Calcipotriol)
Topical corticosteroids (Eumovate)
For thicker plaques in psoriasis what topical treatments can be used? (with examples)
Keratolytics (5% Salicylic acid, similar in structure to aspirin)
Dithranol (dithrocream)
What is the downside to dithranol (dithrocream)?
Tends to leave a brown staining of the skin
What type of topical treatment is first line for treating widespread psoriasis? (with examples)
Coal tar (Carbo-Dome)
What type of topical treatment is first line for guttate psoriasis? (with examples)
Coal tar (Carbo-Dome)
Which topical treatments can cause local irritation?
vitamin D derivatives
coal-tar
keratolytics (Salicylic Acid)
What are the side-effects with coal-tar topical treatment?
It can cause local irritation
Can cause occlusion folliculitis
How should topical treatment to the face be altered?
DO NOT use strong steroids, use:
mild (1% Hydrocortisone)
to
Moderate steroids (Eumovate)
How long can mild to moderate steroids be used on the face?
Up to several weeks
What topical treatments can be used for scalp psoriasis?
Coal Tar shampoo
Vitamin D analogues in the form of scalp applications
or
Topical steroids in the form of scalp applications
What treatment strategy can be used for psoriasis in the flexures?
Same as for the face:
DO NOT use strong steroids, use:
mild (1% Hydrocortisone)
to
moderate steroids (Eumovate)
What are the two main types of phototherapy?
UVB
PUVA (psoralen UVA)
How long does UVB phototherapy last?
3 times a week
for about 7 weeks
What is UVB phototherapy particularly useful for?
Guttate psoriasis
What is the procedure for PUVA light therapy?
The skin is sensitised with psoralens either
tablets or in a solution (for bathing)
this occurs 2 hours before exposure to
UVA
What are the side-effects of phototherapy?
Erythema (like sunburn)
Pruritus
(nausea from psoralen tablets)
Which type of phototherapy has a higher risk of skin cancer?
PUVA (but only after multiple courses)
What are the main systemic treatments for psoriasis?
1) Methotrexate
2) Cyclosporin
3) Acitretin
(4) Biological agents)
How often is methotrexate taken?
once per week
What is methotrexate good for?
Joints and the skin
What is methotrexate bad for? (who can it not be used in)
The liver (thus cannot be used in alcoholics)
What monitoring should be done with methotrexate?
FBC
LFT’s
For how long can cyclosporin be used and why?
1-2 years as it has long-term side-effects
What are the side effects of cyclosporin?
HTN
Nephrotoxicity
Increased risk of skin cancers
When should cyclosporin be used with caution?
If pt has HTN, as it can cause this
If pt has had previous phototherapy as both increase the risk of skin cancer
What should the pt have monitored if they are on cyclosporin?
BP
U+E’s
What are the side-effects of acitretin? (who tolerates it better)
dry skin and dry lips (elderly tolerate it better)
teratogenicity (effects last for max 2 years after stopping drug)
What should be monitored in acitretin?
Fasting lipids
LFTs
When should biological agents be used in psoriasis?
In severe cases where all other treatments have failed
What are the biological agents available? (what are they)
Infliximab (TNF-α antagonists)
Etanercept (TNF-α antagonists)
Efalizumab (a humanized monoclonal antibody)
Which biological agents are given I.V.?
Infliximab
Which biological agents are given subcutaneously?
Etanercept +
Efalizumab
How does Efalizumab work?
It is a humanized monoclonal antibody
which by blocks
T-cell activation
and migration
What do erythrodermic psoriasis and generalized pustular psoriasis have in common?
They both often cause systemic symptoms and need admitting for these.
What is often the treatment for erythrodermic psoriasis and generalized pustular psoriasis?
Supportive treatment:
1) BP monitoring
2) Temp monitoring
3) Urine output monitoring
For the skin:
1) Greasy emolients
2) Potent topical steroids
(3) Systemic steroids if severe enough)
How common is psoriasis?
2% of the population have it
Which gender is more commonly affected by psoriasis?
M=F
What are the two age groups who commonly get psoriasis?
early 20’s and 50’s
What phenomena can psoriasis exhibit?
Kõebner phenomena
What normally precedes guttate psoriasis?
Acute streptococcal infection
What proportion of the body is covered in erythrodermic psoriasis?
more than 90%
What can precipitate generalised pustular psoriasis?
Steroid withdrawal
What does the rash in generalised pustular psoriasis look like?
Background of erythema with sheets of pustules
