What is psoriasis?
Autoimmune chronic inflammatory diseases of the skin.
Occurs due to overstimulation of immune cells that causes excessive proliferation of keratinocytes.
Silvery scaling of skin and itching.
Not contagious and not severe in many cases (outpatient mx)
Erythematous papules and silvery-white scaling plaques
Well demarcated, raised, red patches
Usually not itchy (pruritus is typically mild - 80% of cases)
Affects scalp, back, elbows and knees (extensor surfaces), and nails (thimble pitting).
Erythematous- superficial redness caused by dilation of capillaries.
Nail pitting - small, round depression in the nail.
Well demarcated individual thick, scaly, erythematous lesions
numerous small, scaly, red or pink, tear-drop shaped lesions
Psoriatic nail disease
Inflammation of joints on hand, feet and spine that can occur with psoriasis
appears as red bumps filled with noninfectious pus (pustules)
occurs in skin folds and flexor surfaces creases of joints
generalized erythematous lesions.
affects the scalp
Most common type
Thick, scaly, erythematous lesions
Lesions are red with silver-white scaling
Extensor surfaces of elbows and knees.
Scalp (can cause temporary hair loss)
Nails- pitting and onycholysis
Onycholysis - separation of the nail from the nail bed
Often preceded by Streptococcal infection (Streptococcus pharyngitis)
There is increase in cutaneous blood flow, heat loss, and water loss
Skin becomes red.
Scaling is absent (although this can proceed the erythroderma).
Genitals (between thigh and groin)
Under an overweight abdomen (panniculus)
Under the breasts (inflammatory fold)
Increased by friction and sweat
Vulnerable to fungal infections
Looks like smooth inflamed patches on skin
Joint and Connective tissue inflammation.
Most common joints affected:
Fingers and toes
Results in Dacylitis
Knees, hips, spine (spondylitis)
Morning stiffness of affected joints
Dacylitis - Sausage shaped swelling of fingers and toes.
Can be localized, common to hands and feet
Or generalized, widespread patches
Beta blockers, anti-malarial, lithium, NSAIDs, systemic steroid withdrawal
3. Alcohol and smoking
4. Emotional stress
5. Local trauma
Mild (3% of the body)
Moderate (3-10% of the body)
Degree of severity is based on:
proportion of body surface area affected
disease activity (plaque, redness, scaling)
response to previous treatments
impact of the disease in the patient
Based on appearance of the skin
Skin biopsy, or scrapping - to rule out other disorders
Biopsy shows clubbed rete pegs if positive for psoriasis
small pinpoint bleeding when scales are scraped off
Topical corticosteroids (triamcinolone, fluocinonide, clobetasol), emollients, topical retinoids (tazarotene), vitamin D analogs (calcipotriene, calcitriol)
For facial areas
Topical tacrolimus and Pimecrolimus
Phototherapy, MTX, cyclosporine, anti-T cell agent, anti-TNF agent
Vitamin D analogs
Avoid use on delicate skin areas (face, flexures) because of irritation.
Combine with steroids to increase efficiency
Anti-inflammatory, anti-pruritic, anti-mitotic
For severe generalized psoriasis intolerant after topical therapy
S/E: hepatic fibrosis, myelosuppression, teratogenic
S/E: myelosuppression, skin reactions, liver toxicity, teratogenic
S/E: renal toxicity, HTN, gingival hypertrophy