There are five main types of psoriasis. Each type has different symptoms and characteristics, and a psoriasis patient may present with more than one type, which may also change over time.

Plaque psoriasis is the most common type, characterized by sharply defined red-to-purple, scaly plaques that are distributed somewhat symmetrically. For some patients, the skin may be red with silvery white scales; however, for patients with skin of color, this may look more violaceous. Although most commonly seen on the scalp, knees, elbows and in or around the umbilicus and lower back, plaque psoriasis can affect any area of the body. Plaque psoriasis may also present with nail involvement, such as pitting, onycholysis, subungual hyperkeratosis and “oil spots.”

Erythrodermic psoriasis (also called exfoliative psoriasis) consists of widespread inflammation of the skin characterized by generalized erythema, scaling and exfoliation. Patients may be ill and have hypo- or hyperthermia, electrolyte disturbances, protein loss, dehydration, renal failure and cardiac abnormalities. Severe nail involvement is also characteristic of erythrodermic psoriasis.

Pustular psoriasis is characterized by individual or coalescing sterile pustules. Pustular psoriasis may present as either generalized (von Zumbusch psoriasis) or localized pustules, most often on the palms of the hands or soles of the feet (palmoplantar pustular psoriasis).

Guttate psoriasis is characterized by mostly small, red, scaly papules. “Droplet” lesions may occur over the entire body surface, with the trunk being most commonly affected. This type of psoriasis tends to occur in younger patients, and often follows a strep infection (most commonly strep pharyngitis).

Inverse psoriasis (also called flexural or intertriginous psoriasis) is a seborrheic-dermatitis-like form that occurs in the body folds such as underarms, under breasts, in the genital area and the gluteal cleft.

The clinical manifestations of psoriasis are well-known and usually recognized easily. A complete skin examination, including the nails and scalp, should be performed. Additionally, a skin biopsy may also be done for further confirmation.

The severity of psoriasis is determined by measuring the body surface area (BSA) involved and by the effect of psoriasis on the patient’s quality of life and ability to function. Psoriasis affecting less than 3 percent BSA may be considered mild, 3 to 10 percent as moderate and more than 10 percent as severe.

However, a patient may have psoriasis that covers only a small area, but if it is highly visible or debilitating, it could be considered a severe case. For example, psoriasis involving sensitive areas, such as the face or genital area, or palms of the hands and soles of the feet, are often disabling and may be considered severe even if the rest of the body is not extensively involved.

Disease severity classification serves as a reference point for the physical aspects of the disease, but not the emotional and social aspects. Clinical assessment should include the patient’s perspective on subjective factors such as itching, pain, loss of sleep and effect on daily activities.

The Koo-Menter Psoriasis Instrument (KMPI) is a short assessment tool that includes a validated Health Related Quality of Life index, a Psoriasis Quality of Life questionnaire and other assessments from both the patient’s and the physician’s perspective. Request copies of the KMPI from medevents@psoriasis.org.

Key points to keep in mind when recommending treatments:

• Patients should not be forced to fail one therapy to qualify for a more appropriate therapy. This is called step therapy. Contact our Patient Navigation Center for help with insurance denials and other treatment-access issues that your patients may be facing.
• Ongoing therapy is often required to maintain remission.
• Life factors such as employment, childbearing potential, alcohol intake, access to therapies, comorbidities, response to sunlight, and response to prior therapies must be considered in selecting the ideal treatment for a patient.
• Psoriasis can cause disabilities similar to cancer, diabetes, and other major diseases.