Psoriasis Management

Introduction to Psoriasis

Psoriasis is a chronic skin condition with several clinical variants, including plaque, inverse, erythrodermic, pustular, and guttate psoriasis, affecting different body areas and having distinct characteristics, according to the American Academy of Dermatology 1
Plaque psoriasis is the most common form, affecting over 80% of patients, and is characterized by well-demarcated, erythematous plaques with silvery scale, commonly found on the scalp, elbows, knees, and presacral region 1
Other variants include inverse psoriasis, characterized by erythematous plaques with minimal scaling in skin folds, and erythrodermic psoriasis, a severe form with generalized erythema and systemic symptoms 1

Psoriasis severity is classified based on body surface area (BSA) affected, with mild psoriasis defined as <3% BSA, moderate psoriasis defined as 3-10% BSA, and severe psoriasis defined as ≥10% BSA, as classified by the American Academy of Dermatology 2
The classification of psoriasis severity can also be based on the following table:
Classification BSA Affected
Mild <3%
Moderate 3-10%
Severe >10% or involvement of special areas
3
Psoriasis severity is not solely determined by body surface area, as location matters significantly, and even when affecting less than 5% of body surface area, psoriasis in special locations can be considered severe, as noted by the American Academy of Dermatology 4

Classification	BSA Affected
Mild	<3%
Moderate	3-10%
Severe	>10% or involvement of special areas

Psoriatic arthritis is an inflammatory arthropathy associated with psoriasis, and has a strong association with nail psoriasis, as described by the American Academy of Dermatology 1
Psoriasis is also associated with cardiometabolic diseases, autoimmune conditions, and psychological disorders, and a holistic approach to management should always assess for these comorbidities, according to the American Academy of Dermatology 2

Erythrodermic psoriasis may resemble other forms of erythroderma, and treatment considerations should avoid undertreatment of seemingly "mild" disease and overuse of high-potency topical steroids in sensitive areas, as noted by the American Academy of Dermatology 2, 5
Topical corticosteroids, medium to high potency, are recommended by the American Academy of Dermatology for elbow plaques, and vitamin D analogs + topical corticosteroids have superior efficacy compared to either agent alone, as suggested by the American Academy of Dermatology 5, 3
Methotrexate is recommended by the American Academy of Dermatology as a first-line systemic therapy for moderate-to-severe disease, and treatment pitfalls to avoid include undertreatment, overuse of high-potency topical steroids, and failure to address psychological impact, as noted by the American Academy of Dermatology 6, 5

Common locations for psoriasis include the scalp, elbows, knees, presacral region, trunk, and intertriginous areas, with special areas like the face, genitals, hands, feet, nails, and intertriginous regions often causing disproportionate physical and emotional distress, according to the American Academy of Dermatology 1, 4, 5
Intertriginous areas require careful steroid use due to atrophy risk, as noted by the American Academy of Dermatology 1