Psoriasis

Question 1

what is psoriasis

Answer 1

• Chronic Inflammatory disorder

- Peaks: 16-22 & 57-60 yr

Question 2

etiology of psoriasis

Answer 2

• Idopathic? (dont know all of the etiology)
• Autoimmune
• genetic component (approx 30%)
• Autoimmunity -HLA gene (human leukocyte antigen) is gene complex encoding the major histocompatibilty complex (MHC) proteins in humans. These cell surface proteins are responsible for regulation of immune response

Question 3

Patho of psoriasis

Answer 3

• T cell autoimmune response
• due to skin trauma (infection or incision) to the skin
• T cells activated and brings about an immune response
• mediators released
• triggers abnormal growth of keratinocytes & blood vessels (not destroying keratinocytes altering growth
• Influx of inflammatory cells causing inflammatory damage
• Epidermal cell cycle normally takes about 30 days (1 month), with psorasis there is an increased epidermal cell turnover, takes about 3 days, this causes epidermal thickening (hyperkeratosis), cells stack, not shedding cause scaly patches
• Remissions & exacerbation (worse than previous) -typical presentation, exacerbated by stress, trauma, infection & drugs

Question 4

what do keratinocytes produce

Answer 4

cells that produce keratin (protein which is found in hair & nails)

Question 5

what is the HLA gene?

Answer 5

(human leukocyte antigen) is gene complex encoding the major histocompatibilty complex (MHC) proteins in humans. These cell surface proteins are responsible for regulation of immune response

Question 6

what are the mnfts of psoriasis?

Answer 6

psoriatic patches on: -knees, -elbows, scalp, sacral region of back (typically appear here, but can also appear elsewhere)

nail dystrophy & pitting (30-50% of individuals will have)

psoriatic arthritis in distal joints (toes & fingers) is a complication of psoriasis

Question 7

treatment of psoriasis

Answer 7

-no cure
-topical (management):
-salicylic acid (component of aspirin, softens lesions, hard scaly patch & helps to remove
-coal tar (apply to lesions for several days a week applied for several hours, not understood mechanisms but helps)
-anthralin (deals with & removes lesions)
-steroids (anti-inflma, topical steroids are better than systemic)
-Vitamin D (modulates the keratinocytes & T cells)
-retnoids (anti-inflm)
Systemic drugs: -Immunomodulator drugs ex. methotrexate (anti-folate, inhibits DNA synthesis thus inhibiting cell division, also can be used as a cancer drug depend on dosing) ex. cyclosporine (same action as methotrexate)

Biologic agents ex. TNF (tumor necrosis factor, necrosis of tumor cells in psoriasis used for regulation of keratinocytes (accelerated epidermal cycle) also regulates & brings about apoptosis = programmed cell death

Phototherapy (there is ultraviolet a rays & ultraviolet b rays, ultraviolet b rays are used with phototherapy)