Psoriasis
Psoriasis
Diagnosis
Before the physical examination, the doctor may ask whether you or your family have had psoriasis or immune disorders.
The doctor may also ask if you have noticed changes in your skin that accompany changes in the weather, and will ask about any medications you are taking.
When trying to diagnose psoriasis, the doctor will look for red skin that itches and burns, and is noticeably thicker than skin in other areas [Table 1].
Although psoriasis can affect any skin site, it is usually found on the elbows, knees, scalp, lower back, face, palms, and soles of the feet. Other common areas include the fingernails, toenails, and soft tissue of the mouth and genitals. Psoriasis has many forms. Each type differs in severity, duration, location, pattern, and appearance of the scales.
Table 1. Forms of Psoriasis
| Type |
Description |
| Plaque |
Lesions consisting of thickened red skin coated with silvery scales. |
| Guttate |
Tiny, drop-like lesions that occur on the trunk, limbs, and scalp. Usually triggered by a bacterial infection. Most common in children and young adults. |
| Pustular |
Blisters of noninfectious pus on the skin as a result of medications, infections, emotional stress, or exposure to particular chemicals. Can affect large or small areas of the body. |
| Inverse |
Large, dry, smooth, vividly red plaque in the folds of the skin near the genitals, under the breasts, or in the armpits. Caused by hypersensitivity to friction and sweating. |
| Erythrodermic |
Widespread scaling and inflammation of the skin resulting from severe sunburn or use of oral steroids or other drugs. Produces itching and pain. |
If a physician suspects psoriasis, he or she may examine a small skin sample or biopsy to confirm the diagnosis.
Because other conditions can resemble psoriasis, the physician may need to analyze a skin biopsy after carefully examining the skin, nails, and scalp.
If you are diagnosed with psoriasis, the doctor will examine your skin to determine the severity of the disease [Table 2].
Table 2. Forms of Psoriasis
|
Mild
|
Lesions on less than 2% of body surface
Isolated patches on the knees and elbows |
|
Moderate
|
Lesions on 2% to 10% of body surface
Lesions on arms, legs, torso, and scalp |
|
Severe
|
Lesions or pustules cover more than 10% of body surface
Lesions on the hands or feet, legs, knees, arms, legs, torso, scalp, and fingernails |
If you have joint inflammation and pain in addition to psoriasis, you may have psoriatic arthritis.
Approximately 7% to 30% of people with psoriasis have psoriatic arthritis. In some cases, the arthritis worsens as the skin condition worsens. Occasionally, improvement of the skin during therapy also results in improvement of the arthritis.
Prevention and Screening
Because no one knows what causes psoriasis, there are no methods of prevention.
Psoriasis itself cannon be prevented; however, you may begin to notice events that trigger outbreaks, such as emotional stress, injury to the skin, some types of infection, and reaction to certain drugs.
