Diagnosing Psoriasis — How to Test and Accurately Diagnose Psoriasis

Psoriasis is a chronic autoimmune disease that speeds up the life cycle of skin cells, causing red patches and scales to form on the surface of the skin. Understanding this condition and learning how to manage it is essential for leading a fulfilling life with psoriasis — this starts with an early and accurate diagnosis.

What Exactly Is Psoriasis?

Psoriasis is an autoimmune condition that primarily affects the skin. In simple terms, it’s a condition where your immune system mistakenly attacks healthy skin cells, leading to red, scaly patches that can be itchy and sometimes painful. While its physical manifestations may be unsettling, the condition is more common than you think, affecting approximately 2%–3% of the global population. (Source)

Why Should You Aim for an Early and Accurate Diagnosis?

You might be tempted to self-diagnose your psoriasis, especially with so much information available online. But while your knowledge of your own body is paramount, self-diagnosis is not recommended. Consulting with a dermatologist or other health care provider can provide a definitive diagnosis and the expertise to differentiate psoriasis from other skin conditions that may look similar, but require different treatments. Getting an early and accurate diagnosis is crucial for several reasons. 

  • early detection: The sooner psoriasis is identified, the better the chances of managing it effectively. Psoriasis can be a lifelong condition, but with the right treatment plan, you can manage the symptoms and lead a comfortable life. 
  • accurate diagnosis: Without a proper diagnosis, you’re essentially shooting in the dark when it comes to treatment, which can lead to unnecessary stress and may even worsen your symptoms. Misdiagnosis is also a concern; conditions such as eczema, fungal infections, and even bacterial infections can mimic psoriasis, making it crucial to get the diagnosis right the first time
  • effective management: By taking a proactive role, you can help control flares and avoid triggers for your psoriasis.

(Source, Source)

In this guide, we’ll walk you through the various methods health care professionals use to diagnose psoriasis. We’ll also share some strategies to help you get a proper diagnosis. We aim to empower you with knowledge so you feel confident when discussing your symptoms and treatment options with your health care provider.

Let’s dive right in and explore how psoriasis is diagnosed.

How Do Health Care Providers Diagnose Psoriasis?

So, you’ve noticed some skin changes and you’re wondering what’s going on. The first step in getting to the bottom of it is usually a clinical examination. Let’s talk about what that involves and why your family history might be more relevant than you think.

Physical Examination

When you visit a health care provider for suspected psoriasis, the first thing they’ll likely do is a thorough physical examination. This involves checking your skin for the characteristic red, scaly patches that are often associated with psoriasis. But they won’t just look at your skin. They’ll also examine your nails for any signs of pitting or discoloration, and your joints for any signs of psoriatic arthritis.

The reason for this comprehensive check is that psoriasis can manifest in different ways and in different areas of the body. While having the plaques that are characteristic of psoriasis may make your diagnosis pretty straightforward, sometimes other symptoms are more prominent, making diagnosis a bit tricky. (Source)

Why Is Your Family History Important?

Psoriasis can run in families. If you have a family history of psoriasis or other autoimmune diseases, it could provide a valuable clue in confirming a diagnosis. This information can help your health care provider determine if additional tests or a skin biopsy are needed for a more definitive diagnosis.

Your family history is a vital piece of the diagnostic puzzle, so don't hesitate to share this information during your clinical examination. It could make all the difference in how quickly and accurately your condition is diagnosed. (Source)

Laboratory Tests and Psoriasis: What You Need to Know

Laboratory tests can provide a more comprehensive picture of your health — let’s dive into why your provider may want to order laboratory tests, and what those tests can tell you.

The Role of Blood Tests in Diagnosing Psoriasis

Psoriasis is generally diagnosed through a physical examination of the skin, and blood tests are not usually the go-to method for diagnosis. However, that doesn’t mean blood tests are entirely out of the picture. In some cases, health care providers may recommend blood tests to rule out other conditions that might mimic psoriasis symptoms. This is a precautionary step to ensure you’re getting the most accurate diagnosis and, subsequently, an effective treatment plan that is tailored to your needs.

What Types of Blood Tests Might Be Conducted?

Blood tests can be useful in eliminating the possibility of other autoimmune conditions that may have symptoms similar to those of psoriasis, such as lupus or rheumatoid arthritis. By ruling out these other conditions, your health care team can focus on crafting a personalized treatment plan that targets psoriasis specifically. This is particularly important for those experiencing moderate to severe symptoms, as a misdiagnosis could lead to ineffective or even harmful treatments.

If your health care provider does recommend blood tests, they might include:

  • complete blood count (CBC): This test checks for signs of infection or inflammation and is often the starting point. (Source)
  • C-reactive protein (CRP): This test measures levels of inflammation in the body, which can be elevated in various autoimmune conditions, including psoriasis. Higher levels of CRP are associated with more severe psoriasis symptoms and more advanced progression of the disease. (Source)
  • rheumatoid factor (RF): This test is particularly useful for ruling out rheumatoid arthritis, another autoimmune condition that can sometimes overlap with psoriasis symptoms. (Source, Source)
  • antinuclear antibody (ANA): This test detects the presence of antinuclear antibodies, which target components found in the nuclei of various cells. ANA are not specific to psoriasis but their presence or absence can help rule out other conditions, such as lupus. (Source)
  • erythrocyte sedimentation rate (ESR): The ESR is a measurement of red blood cell behavior that indicates whether the cells are clumping together in an abnormal way, an indication of inflammation. Elevated ESR levels have been associated with psoriatic arthritis, indicating systemic inflammation often seen in autoimmune conditions. (Source)
  • HLA-B27: This test looks for the presence of a protein called HLA-B27, which is linked to psoriatic arthritis. If you are positive for HLA-B27 you may be genetically predisposed to developing the condition. (Source)

These tests are not definitive for psoriasis but can help rule out other conditions and provide valuable insights into your overall health. They offer a more comprehensive view of what’s going on in your body, helping to guide your personalized treatment plan.

What Happens After the Blood Tests?

Once the blood tests are done and the results are in, your health care provider will discuss the findings with you. If other conditions are ruled out, the focus will shift entirely to managing your psoriasis. 

This is where WellTheory’s holistic approach comes into play. We offer evidence-based strategies in nutrition, stress management, and more to complement your medical treatments. Remember, you’re not alone on this journey. We’re here to provide continuous, empathetic care every step of the way.

Skin Biopsy in Diagnosing Psoriasis

To provide a precise and accurate diagnosis for psoriasis, especially when symptoms are atypical or resemble other skin conditions, a skin biopsy may be deemed necessary. Understanding when this procedure is warranted and what it entails can demystify the process, providing reassurance in your health care journey.

Why a Skin Biopsy?

At times, the symptoms of psoriasis may resemble those of other skin conditions, making a precise diagnosis challenging. A skin biopsy can be helpful in differentiating between them. The procedure involves removing a small sample of skin for microscopic examination to confirm or rule out psoriasis or other skin disorders.

A skin biopsy can unveil the cellular and tissue characteristics specific to psoriasis, such as patterns unique to each type and the rate at which skin cells grow and shed. This microscopic examination can provide a clear picture, assisting your health care provider in tailoring a treatment plan to your needs.

When Is a Biopsy Recommended?

The necessity for a skin biopsy often arises in situations where:

  • Your symptoms are atypical or do not respond as expected to initial treatments.
  • There’s a need to distinguish psoriasis from other similar-appearing skin conditions, such as eczema or dermatitis.
  • It’s essential to assess the severity of your psoriasis, particularly if it’s not clear from a physical examination alone.

(Source, Source)

What Does the Procedure Entail?

A skin biopsy is typically a quick procedure performed under local anesthesia to minimize any discomfort. It’s a relatively safe procedure with minimal risks. The extracted skin sample is then sent to a laboratory where it’s examined under a microscope by a pathologist, who can identify the tell-tale signs of psoriasis or other skin conditions. (Source)

Is Biopsy the Only Option?

A skin biopsy is generally considered when other diagnostic methods are inconclusive. It’s not the first go-to option but can be a decisive one when needed. So, if your health care provider suggests a skin biopsy, it’s usually because they want to be absolutely sure about your diagnosis so they can provide the best possible care.

Though a skin biopsy might sound uncomfortable, it’s a straightforward procedure that can provide invaluable insights into your skin health. With a definitive diagnosis, your care team can devise a more targeted treatment plan, taking a step closer to managing your psoriasis effectively.

What Are Advanced Imaging Techniques in Psoriasis Diagnosis?

If you’ve been through the initial stages of psoriasis diagnosis, such as clinical examinations and maybe even a skin biopsy, you might be wondering, “Are there more advanced ways to confirm my condition?” The answer is yes, there are advanced imaging techniques that can offer a more detailed look at your skin. Let’s explore a couple of these methods.

Reflectance Confocal Microscopy

Reflectance confocal microscopy (RCM) is an advanced imaging technique that provides a real-time, cellular-level view of the skin without requiring a biopsy. This technique reveals horizontal tissue sections of the epidermis and upper dermis, enabling the evaluation of skin tumors and inflammatory and infectious diseases. This method can be especially useful when a definitive diagnosis is challenging to make through other methods. (Source, Source)


Dermoscopy is another non-invasive diagnostic method employing a specialized magnifying lens to scrutinize skin lesions. This technique has proven to be more sensitive than RCM in diagnosing psoriasis, offering a higher overall diagnostic accuracy. Through dermoscopy, healthcare providers can discern features such as red dots, globules, and blotches often indicative of psoriasis, helping to distinguish it from other skin disorders such as lichen planus that may look similar to the naked eye​. (Source)

Are These Advanced Methods for Everyone?

While these advanced techniques can provide a wealth of information, they’re generally used in more complex or uncertain cases. The main advantage of these advanced methods is their ability to provide a more detailed and accurate diagnosis. This can be particularly beneficial if you’ve been experiencing symptoms that are hard to pinpoint or if other diagnostic methods have been inconclusive.

How Can You Aid in Your Own Psoriasis Diagnosis?

You can take proactive steps to assist your health care provider in making an accurate diagnosis. By putting these tips into action, you’re not just preparing for a medical appointment; you’re taking an active role in your journey to better health.

This prep work complements the daily lifestyle choices — such as nutrition, stress management, and sleep hygiene — that you should be focusing on as part of your long-term plan. You’ll be collaborating with your health care team and actively participating in your own well-being.

Let’s explore some strategies that can empower you when you are getting ready to seek medical care.

Preparing for Your Medical Appointment 

Your appointment is a valuable opportunity to work closely with your health care team in managing your autoimmune condition. Preparing adequately for this appointment can significantly help in creating a personalized and effective care plan. Here are some practical tips to help make the most out of this visit.

Keep a Symptom Diary

Start by jotting down your symptoms in a diary. Note when they occur, how long they last, and any suspected triggers. When did your symptoms pop up? How long did they stick around? Were there any specific triggers, such as stress or foods, that seemed to set them off?  A diary like this is a treasure trove of data for your health care provider. This information helps in tailoring your care plan to your unique needs, promoting better symptom management in the long run.

List Your Medical History

Get a comprehensive list of your personal and family medical history ready. If there’s a history of psoriasis or any other autoimmune diseases in your family, that’s crucial information. Don’t forget to include a list of medications and supplements you’re currently taking. It’s all part of the bigger picture, helping your health care provider assess your situation holistically.

Prepare Your Questions

You’re likely to have questions — write them down so you don’t forget! These could range from inquiries about diagnostic tests to potential treatment options and lifestyle changes that might alleviate your symptoms. Remember, your journey to better health is a collaborative effort. Asking questions empowers you to actively participate in your care plan.

Take Pictures

Psoriasis mostly affects your skin, and the symptoms tend to fluctuate. Snap some photos to show your provider. Clear and detailed pictures can sometimes speak louder than words. These visuals offer your health care team additional context for diagnosis and treatment planning.

Consider Bringing a Support Person

It’s okay to want a little emotional backup. If possible, bring your partner, a friend, or a family member along for emotional support. Not only can they offer moral support, but they can also help you remember important details from the appointment. Sometimes, two sets of ears are better than one, especially when it comes to understanding medical advice

The Bottom Line: Why Early and Accurate Diagnosis Matters

Early and accurate diagnosis is your first step toward reclaiming your life from psoriasis. It opens the door to effective treatments and helps you make lifestyle changes that can significantly improve your quality of life. The sooner you know, the sooner you can act.

How Can WellTheory Help?

You’re not alone on this journey. At WellTheory, we’re committed to providing evidence-based, personalized care that addresses your unique needs. Our approach is holistic, focusing not just on symptoms but on overall well-being. Whether it’s nutritional guidance, stress management techniques, or lifestyle changes, we’ve got you covered. We’re here to empower you with knowledge and tools to manage your condition effectively.


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