Psoriasis

35 y/o M with a h/o HTN, DM, and tobacco/alcohol abuse disorder presents with pruritic skin scaling. Reports recent skin trauma in the most heavily affected areas. Family history includes psoriasis. BMI > 35 kg/m^2. Physical exam reveals sharply defined, erythematous plaques overlying course scales present on the scalp, ear, extensor surface of elbows, knees, and gluteal cleft. Plaque size ranges from 1 to 10 cm with positive Auspitz sign.

• Initial treatment

  • Start topical steroids

    • Apply two weeks and then discontinue for two weeks

    • Patient may continue two week cycle of use and discontinuation if symptoms recur

  • Scalp psoriasis

    • Apply 3% coal tar shampoo (e.g. MG 217) to wet scalp and leave in place for 5 minutes before rinsing

    • Continue daily use until symptoms resolve

• Refractory disease

  • Continued symptoms despite steroid use: Add topical calcitriol twice daily to affected areas (maximum weekly dose 200 g)

  • Consider skin biopsy versus dermatology referral

Notes

• Epidemiology

  • Obesity, tobacco, and alcohol use are risk factors for psoriasis

  • HTN and DM are often comorbid with psoriasis

  • Psoriasis is an autoimmune condition and may be more prevalent in patients with other forms of autoimmune disease

• Presentation

  • The vignette describes the most common form of psoriasis, chronic plaque psoriasis

  • Koebner phenomenon: Development of skin lesions such as psoriasis following skin trauma

  • Auspitz sign: Pinpoint bleeding when overlying scale is removed

• Treatment

  • Topical calcitriol: Vitamin D analog that can be used continuously unlike topical steroids

  • Tazarotene: Vitamin A analog also commonly used in psoriasis treatment

  • Severe disease may be treated with calcineurin inhibitors (e.g. tacrolimus) or biologic agents

• More information available through the National Psoriasis Foundation