DERM: Psoriasis

Question 1

what is psoriasis?

Answer 1

chronic autoimmune condition that causes recurrent symptoms of psoriatic skin lesions.

• Red scaly plaques
• Disease on scalp, elbows and knees
• Potential involvement of the whole skin
• Nail disease
• Joint disease in 5-10%

Question 2

where is psoriasis commonly found on the body?

Answer 2

commonly over the extensor surfaces of the elbows and knees and on the scalp

Question 3

what causes psoriasis?

Answer 3

These skin changes are caused by the rapid generation of new skin cells, resulting in an abnormal buildup and thickening of the skin in those

• genetic predisposition
• precipitated by e..g. infection, stress, drugs

Question 4

what is Plaque psoriasis?

Answer 4

thickened erythematous plaques with silver scales, commonly seen on the extensor surfaces and scalp. The plaques are 1cm – 10cm in diameter. This is the most common form of psoriasis in adults.

Question 5

what is the most common type of psoriasis?

Answer 5

Plaque psoriasis

Question 6

what is Guttate psoriasis?

Answer 6

• second most common psoriasis
• commonly occurs in children
• It presents with many small raised papules across the trunk and limbs. The papules are mildly erythematous and can be slightly scaly. Over time the papules in guttate psoriasis can turn into plaques. Guttate psoriasis is often triggered by a streptococcal throat infection, stress or medications. It often resolves spontaneously within 3 – 4 months.

Question 7

what is Pustular psoriasis?

Answer 7

is a rare severe form of psoriasis where pustules form under areas of erythematous skin.

• patients can be systemically unwell
• should be treated as a medical emergency

Question 8

what is Erythrodermic psoriasis?

Answer 8

rare severe form of psoriasis with extensive erythematous inflamed areas covering most of the surface area of the skin.

Question 9

which type of psoriasis is more common in children?

Answer 9

Guttate psoriasis is more common in children, often triggered by a throat infection

Question 10

which signs are suggestive of psoriasis?

Answer 10

Auspitz sign

Koebner phenomenon

Residual pigmentation

Question 11

with reference to psoriasis what is Auspitz sign?

Answer 11

Auspitz sign refers to small points of bleeding when plaques are scraped off

Question 12

with reference to psoriasis what is Koebner phenomenon?

Answer 12

Koebner phenomenon refers to the development of psoriatic lesions to areas of skin affected by trauma

Question 13

with reference to psoriasis what is Residual pigmentation?

Answer 13

Residual pigmentation of the skin after the lesions resolve

Question 14

how do you score psoriasis in a clinical setting?

Answer 14

Clinical: PASI scoring
(Psoriasis Area and Severity Index)

Patient focussed: DLQI
(Dermatology Life Quality Index)

Question 15

what are the treatment options for psoriasis?

Answer 15

• Topical steroids
• Topical vitamin D analogues (calcipotriol)
• Topical dithranol
• Topical calcineurin inhibitors (tacrolimus) are usually only used in adults
• Phototherapy with narrow band ultraviolet B light is particularly useful in extensive guttate psoriasis

Question 16

what is Nail psoriasis?

Answer 16

describes the nail changes that can occur in patients with psoriasis. These include nail pitting, thickening, discolouration, ridging and onycholysis (separation of the nail from the nail bed).

Question 17

what is Psoriatic arthritis?

Answer 17

occurs in 10 – 20% of patients with psoriasis and usually occurs within 10 years of developing the skin changes. It typically affects people in middle age but can occur at any age.