Psoriasis
(Redirected from Psoriatic arthritis)
Background
- Psoriasis is a chronic and relapsing disease
- Often begins in the 2nd or 3rd decade of life
Types
- Plaque: also known as psoriasis vulgaris, makes up about 90% of cases. It typically presents as red patches with white scales on top. Areas of the body most commonly affected are the back of the forearms, shins, navel area, and scalp.
- Guttate: drop-shaped lesions.
- Inverse: red patches in skin folds
- Pustular: presents as small non-infectious pus-filled blisters
- Erythrodermic: occurs when the rash becomes very widespread, and can develop from any of the other types. Fingernails and toenails are affected in most people with psoriasis at some point in time. This may include pits in the nails or changes in nail color.
Triggers
- Stress
- Trauma
- Drugs: NSAIDs, B-blockers
Clinical Features
- Well-demarcated erythematous plaques and papules with silvery white scales
- Epidermal hyperproliferation
- Commonly found on the trunk, scalp, nail pitting, and extensor surfaces
- Auspitz sign: plaque removal reveals pinpoint-bleeding areas
- Associated with psoriatic arthritis, especially in nail involvement
Differential Diagnosis
Plaques
- Psoriasis
- Bowen disease
- Discoid lupus erythematosus
- Drug eruption
- Erythema annulare centrifugum
- Lichen planus
- Lichen simplex chronicus
- Nummular dermatitis (nummular eczema)
- Parapsoriasis
- Pityriasis rosea
- Seborrheic dermatitis
Evaluation
- Generally a clinical diagnosis
Management
- Ketoconazole 2% shampoo
- Hydrocortisone cream 2.5% Neck, Intertriginous Sites
- Triamcinalone ointment or cream 0.1% Extremities, Trunk, and Scalp
- Steroids should not be used for more than 2 weeks
- Systemic steroids should be avoided due to the risk of developing rebound or induction of pustular psoriasis
- Severe pustular psoriasis cases can be treated with infliximab (TNFa inhibitor) or cyclosporine
Disposition
- Discharge