If you’re living with psoriasis, your immune system sends a message to the skin cells, telling them to make more cells than they should. For people without psoriasis, it usually takes up to a month for new skin cells to develop. With psoriasis, new skin cells mature every three to four days. As a result, these cells build up on the skin’s surface, forming thick, scaly patches.

Psoriasis is generally diagnosed through a physical examination of the affected skin. It may be difficult to tell apart from other skin conditions like eczema, dandruff, or cutaneous lupus, and symptoms can vary depending on the severity and your skin tone.

How Is Psoriasis Diagnosed?

A dermatologist specializes in conditions of the hair, skin, and nails. They can help determine and confirm your condition if you experience itchy, dry, thick patches of skin and think you may have psoriasis. If you don’t already see a dermatologist, ask your primary care provider for a referral.

Typically, a dermatologist will diagnose psoriasis by inspecting the affected skin. They’ll look for symptoms of psoriasis like dry, scaly, patches of skin, and thick, inflamed, discolored (red, brown, purple, or gray, depending on your skin tone) plaques of skin with white, silver, or grayish scales. Plaques are a symptom of plaque psoriasis — the most common type of psoriasis.

A dermatologist will examine your entire body, including your scalp and your skin folds, as psoriasis commonly occurs in those areas. They may ask about your family history of psoriasis and other symptoms you’re experiencing. For example, they may ask if you have nail problems, joint pain, or swelling, as well as whether you’ve gone through any major life changes recently. These questions can help a dermatologist get a better picture of your health. If you have joint and nail symptoms, it may help confirm a psoriasis diagnosis. ​

When diagnosing psoriasis, your dermatologist will also diagnose the type of psoriasis you have, and they may discuss how severe your psoriasis is. Although plaque psoriasis is the most common, other types of psoriasis like inverse psoriasis, guttate psoriasis, or erythrodermic psoriasis are possible and appear with slightly different symptoms.

In terms of psoriasis severity, dermatologists may use several tools, including the Psoriasis Area and Severity Index (PASI). With this tool, your dermatologist will rate the severity of your psoriasis based on the intensity of symptoms like discoloration, scaling, and thickness on a scale of zero to four (zero means none and four indicates very severe). Your dermatologist will also inspect your head and neck, arms, midsection, and legs to determine the area or percentage of your body affected by psoriasis symptoms.

Depending on the type and severity of your psoriasis, your dermatologist will create a treatment plan for your specific needs and condition. Mild psoriasis may only be treated with topicals like creams or ointments, whereas severe psoriasis may require biologic therapy. Biologic therapy, also called biologics or biologic drugs, is a treatment option for severe psoriasis. This type of treatment uses medications made from living organisms to target and control certain parts of the immune system that cause psoriasis to develop.

Punch Biopsy

In some cases, your dermatologist may want to rule out other skin conditions by performing a punch biopsy — a type of skin biopsy that’s most commonly used to diagnose psoriasis. The punch biopsy process should only take about five minutes, and your dermatologist can do it right in their office.

Before a punch biopsy, your doctor will clean an area of skin where you’re having symptoms. They may inject an anesthetic such as lidocaine or xylocaine to numb the skin. Then, they’ll use a device to puncture the skin and remove a small section (around 3 millimeters in diameter) of deeper layers of skin (the epidermis, dermis, and superficial fat). They may use one or two stitches to close the incision. ​

After the biopsy, your doctor may apply a bandage to the area from which they removed the skin sample. You may experience some pain in the area after the anesthetic wears off.

Your doctor will then send the skin sample to an outpatient laboratory where a pathologist will evaluate it using a microscope. A microscope helps provide a magnified, clearer view of the skin sample, its characteristics, and the presence of skin diseases like psoriasis. Results from this type of biopsy are usually available within one week. Someone from your dermatologist’s office will either call you or post your results to your online patient portal.

Diagnosing Psoriatic Arthritis

If you have joint symptoms like joint pain, swelling, and stiffness in addition to psoriasis skin symptoms, your doctor may advise you to also be tested for psoriatic arthritis (PsA). According to the National Psoriasis Foundation, around 30 percent of people with psoriasis have PsA.

Diagnosing PsA is a very different process from diagnosing a skin condition like psoriasis. Although there is no one conclusive test for PsA, diagnosis may involve a physical examination, blood tests, or imaging procedures such as X-rays and CT or MRI scans.

Dermatologists often refer patients with PsA to rheumatologists. A rheumatologist specializes in rheumatic diseases and has advanced knowledge in evaluating and treating skin and joint symptoms related to PsA.

Scans allow the doctor to check for joint damage. Blood tests establish how much inflammation is in the body and help the specialist distinguish PsA from other conditions with similar symptoms, such as rheumatoid arthritis. A diagnosis of skin psoriasis helps make a diagnosis of PsA more certain.

When PsA is present alongside psoriasis, it can affect the approach to managing the skin condition. The treatment plan for psoriasis may be adjusted to address the joint symptoms and complications associated with PsA, aiming to provide relief for both the skin and joint issues.

What Is the Prognosis for Psoriasis?

Although symptoms may appear during disease flares and subside during periods of remission, psoriasis is a chronic (ongoing) condition. Each disease flare may bring symptoms to different parts of your body, or you may experience symptoms that recur in the same locations.

There is no cure for psoriasis, but there are effective treatments for many symptoms of psoriasis and psoriatic arthritis (together referred to as psoriatic disease). Psoriasis treatments can help keep your symptoms under control and help keep symptoms from showing up on new parts of your body.

If you have psoriasis, you may wonder whether it can affect your life expectancy. Psoriatic disease is rarely life-threatening. However, people with psoriatic disease have a higher risk of developing comorbidities (when you have more than one condition at a time). ​

Some comorbidities of psoriatic disease include:

• Inflammatory bowel disease
• Metabolic syndrome, which includes high blood pressure, high blood sugar, and/or high cholesterol
• Obesity
• High blood pressure
• Cardiovascular disease
• Cancer
• Diabetes
• Depression and anxiety
• Kidney disease
• Chronic obstructive pulmonary disease (COPD)

Metabolic syndrome, cardiovascular disease, cancer kidney disease, and COPD in particular may affect your life expectancy. People with psoriasis and PsA must maintain a healthy weight, eat a nutritious diet, and get regular exercise to avoid developing these dangerous complications.

Treating your psoriasis can also help reduce your risk of these comorbidities. Regular treatment and follow-up for your psoriasis can help ensure that you’re getting monitored for comorbidities. Regular blood pressure tests and blood work can help with recognizing comorbidities early, in addition to evaluating how your psoriasis treatment is working.

At What Age Does Psoriasis Start To Develop?

Psoriasis usually begins either between ages 20 to 30 or between ages 50 to 60. However, psoriasis may develop in people of any age, even in young children and infants.

Because psoriasis is a chronic condition, you’ll want to work with a dermatologist to come up with a treatment plan for your symptoms. A health care professional can help review your treatment options and devise a plan to help you avoid common triggers and prevent flare-ups.

Find Your Team

MyPsoriasisTeam is the social network for people with psoriasis and psoriatic arthritis. On MyPsoriasisTeam, more than 123,000 members come together to ask questions, give advice, and share their stories with others who understand life with psoriasis.

Have you been diagnosed with psoriasis? How was your diagnostic process? Share your experience in the comments below, or start a conversation by posting on your Activities page.

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