Psoriasis Flashcards
What is psoriasis?
Psoriasis is a chronic inflammatory skin condition characterised by clearly defined, red and scaly plaques.
What is the aetiology of psoriasis?
Psoriasis affects 2–4% of males and females
peaks at 15–25 years and 50–60 years.
How long does it last?
It tends to persist lifelong, fluctuating in extent and severity.
What type of condition is psoriasis classed as?
Immune-medicated genetic skin condition
Where are psoriasis lesions most commonly found? (2)
1) extensor surfaces of knees and elbows
2) scalp
Summarise the pathophysiology of psoriasis:
hyperproliferation of keratinocytes and inflammatory cell infiltration
What is the name of the phenomenon where psoriasis lesions form in regions recently injured by trauma?
Koebner phenomenon
Name 5 triggers of psoriasis:
1) trauma
2) infection
3) stress
4) alcohol
5) drugs
Name the four types of psoriasis:
1) plaque
2) guttate
3) pustular
4) erythrodermic
What is the most common type of psoriasis?
plaque psoriasis
What is the second most common type of psoriasis?
guttate psoriasis
How does plaque psoriasis present?
thickened erythematous plaques with silver scales, commonly seen on extensor surfaces and the scalp
Give the approx. size range of psoriasis plaques:
1-10cm
What would be defined as plaque psoriasis?
Persistent and treatment-resistant
Plaques >3 cm
Most often affects elbows, knees, and lower back
Ranges from mild to very extensive
In which patient group is guttate psoriasis most common?
Children
Describe how guttate psoriasis presents:
small raised papules across the trunk and limbs which are mildly erythematous and slightly scaly
What is the most common identified trigger of guttate psoriasis?
Streptococcal throat infection
How can psoriasis be classified?
Early age of onset <35 years (75%) vs late age of onset >50 years
Acute eg guttate psoriasis vs chronic plaque psoriasis
Localised eg, scalp, palmoplantar psoriasis vs generalised psoriasis
Small plaques (<3 cm) vs large plaques (>3 cm)
Thin plaques vs thick plaques
Nail involvement vs no nail involvement
Describe how pustular psoriasis presents:
pustules form under areas of erythematous skin, often making patients systemically unwell
What two types of psoriasis are considered medical emergencies?
1) pustular psoriasis
2) erythrodermic psoriasis
How does erythrodermic psoriasis present?
extensive erythematous inflamed areas covering most of the skin which come away in large patches, resulting in raw, exposed areas
How do psoriasis plaques present in darker skin?
lesions can appear dark brown, grey or purple
Give two nail changes associated with approx. 50% of psoriasis cases:
1) pitting nails
2) oncolysis
What is oncolysis?
detachment of the nail from the nail bed
