Understanding the 5 Types of Psoriatic Arthritis

Psoriatic arthritis (PsA) is a lifelong inflammatory disease that results when the immune system malfunctions and attacks the joints and skin. The symptoms you might experience often depend on the subtype of PsA you have. It is possible to have more than one type of PsA, and PsA patterns can change with time.

The five types of PsA are asymmetric, symmetric, psoriatic spondylitis, distal interphalangeal predominant, and psoriatic arthritis mutilans.  

This article will discuss the five types of PsA, their symptoms, and how PsA is diagnosed and treated.

Asymmetric Psoriatic Arthritis

Asymmetric PsA, also called asymmetric oligoarticular PsA, affects fewer than five joints. "Asymmetric" means it affects joints on only one side of the body. For example, you may experience pain in your right knee and not your left.

Symptoms usually begin in one knee. Asymmetric PsA will often precede symmetric PsA. PsA generally affects men and women equally, but asymmetric disease usually affects more men than women.

Symptoms

Asymmetric PsA is milder than other subtypes of PsA. It tends to affect the larger joints but can also affect a hand or foot.  

The most common symptoms associated with asymmetric PsA are:  

• Stiff and painful joints on one side of the body
• Stiffness and pain that is worse in the morning
• Enthesitis: Inflammation of the entheses, the areas where tendons and ligaments meet bone
• Dactylitis: Sausage-like appearance of fingers and toes from severe inflammation
• Patches of red, irritated skin covered in scales
• Nail changes in the fingernails and toenails, including nail pitting (small indents), discoloration, and nail bed separation 

Symmetric Psoriatic Arthritis  

Symmetric polyarthritis, also known as symmetric PsA, affects the joints on both sides of the body. For example, it affects both knees or elbows, rather than one of these joints. About 50%–60% of people with PsA have this form, according to a 2013 report in the journal Clinical Reviews in Allergy & Immunology.

In most cases, asymmetric PsA evolves into symmetric PsA. One-third of people with symmetric disease will experience dactylitis and enthesitis.

Symptoms 

Symmetric PsA can affect any joint in the body, and symptoms range from mild to severe. They are similar to those experienced in asymmetric PsA.  

Joint symptoms affect matching parts of the body. Symmetric PsA also causes morning stiffness and skin rashes.

Symmetric PsA is sometimes mistaken for rheumatoid arthritis (RA), another type of inflammatory arthritis that affects both sides of the body. PsA is different from RA because it causes dactylitis and enthesitis. 

Psoriatic Spondylitis 

Psoriatic spondylitis is a subtype of PsA that affects the spine and the pelvis. According to the Spondylitis Association of America, about 20% of people with PsA will develop psoriatic spondylitis.

Symptoms 

Symptoms of this type of PsA may develop anywhere from the neck to the pelvis, but persistent back pain is the most common symptom.  

Additional symptoms of psoriatic spondylitis include:  

• Inflammation and stiffness of the neck and lower back
• Neck pain
• Difficulty with moving the spine
• Connective tissue inflammation
• Peripheral joint involvement in the arms, hips, legs, or feet
• Stiffness in the shoulders
• Arm and leg weakness
• Headaches
• Bladder and bowel problems

Distal Interphalangeal Predominant PsA

The distal interphalangeal (DIP) joints are the joints of the fingers and toes closest to the nails. DIP PsA mainly affects the ends of the fingers and toes. It can also cause nail changes like pitting, discoloration, and nail bed separation.  

Pain in the finger joints is one of the earliest symptoms of this type of PsA. It affects about 5% of people with PsA. This type of PsA often occurs alongside other types of PsA.  

Symptoms  

The symptoms of DIP PsA in the finger joints make it harder to perform simple tasks, such as tying shoes or opening a jar. Stiffness and swelling in the toes make it harder to walk and stand for long periods.  

Symptoms of DIP PsA include:  

• Nail changes
• Dactylitis
• Stiffness of DIP joints, especially in the morning
• Reduced range of motion
• Tendon or ligament pain
  

Psoriatic Arthritis Mutilans 

Psoriatic arthritis mutilans (AM) affects around 5% of people with PsA. It is the most severe type of PsA and damages the hands, feet, fingers, and wrists. Psoriatic AM causes joints to fuse eventually.  

Symptoms  

Symptoms of psoriatic AM are worse during flare-ups, times when symptoms are worse. A PsA flareup can last for days or weeks.  

Psoriatic AM causes the following symptoms:  

• Severe joint pain and swelling in the hands and feet
• The fusing of the bones of the hands and feet
• Ankylosis: Abnormal stiffening and immobility of a joint due to fusion of the bones
• Skin lesions that develop before joint symptoms
• Nail changes 

Over time, psoriatic AM can cause severe joint complications. These might include:

• Opera-glass hand, in which unstable bones and joints in the fingers allow them to retract into one another like a telescope or opera glasses
• Shortening of the fingers or toes
• The inability to hold the fingers in any position
• A pencil-in-cup deformity, in which the bone has worn down into the shape of a pencil tip 
  

Diagnosis  

Early diagnosis of PsA is important. The sooner a person is diagnosed, the earlier they can start treatment to prevent further joint damage.

Diagnosing PsA starts with a medical exam where your healthcare provider will ask various questions about your symptoms and other conditions you may have. They will ask about your family history of PsA and autoimmune skin condition psoriasis or your personal medical history of psoriasis.

The next step in determining the cause of your symptoms is a physical examination. Your healthcare provider will examine your joints for joint tenderness, swelling, and movement difficulties. They will also check for nail symptoms and skin lesions.  

Your healthcare provider will also request blood work and imaging studies to aid in a diagnosis. 

Blood work done for PsA includes C-reactive protein (CRP) and rheumatoid factor (RF) testing. A CRP test measures inflammation levels in the body, and a negative RF can rule out rheumatoid arthritis.

Imaging studies, including X-rays, magnetic resonance imaging (MRI), and ultrasound scans, can help your healthcare provider evaluate the joints for signs of inflammation and damage.  

How Is Each Type of Psoriatic Arthritis Treated? 

While there is no cure for PsA, treatment can prevent the condition from getting worse and improve your quality of life. There are plenty of treatment options for PsA.

The type of treatment your doctor will recommend for PsA will depend on a variety of factors, including:  

• The severity of your symptoms or the type of PsA
• How many joints are affected
• The affected joints
• The extent of damage to affected joints
• Previous responses to treatment
• Your overall health
• Personal preferences

Treatment Options

In general, healthcare providers first recommend nonsteroidal anti-inflammatory drugs (NSAIDs) like Advil (ibuprofen) or Aleve (naproxen) to address symptoms of pain and swelling, as well as oral and injectable corticosteroids and injections for short-term use during flare-ups.  

When NSAIDs and corticosteroids don't help, systemic treatments (those that target the entire body) are the next treatment option. These drugs treat disease symptoms and reduce disease progression. They include conventional disease-modifying antirheumatic drugs (DMARDs) and biologic drug therapies.  

Conventional DMARDs can manage overall inflammation to prevent further joint damage. Examples include Trexall (methotrexate), Azulfidine (sulfasalazine), and Arava (leflunomide).  

Biologic drugs are a newer type of DMARD that targets specific parts of the immune system to reduce inflammation and underlying processes of PsA. Biologics typically cause fewer side effects than conventional DMARDs.

Examples of biologic drug therapies used to treat PsA are:  

Anti-TNF medications, such as:

• Cimzia (certolizumab pegol)
• Humira (adalimumab)
  
• Remicade (infliximab)

Interleukin inhibitors, such as:

• Cosentyx (secukinumab)
• Stelara (ustekinumab)
• Taltz (ixekizumab)
• Otezla (apremilast)
• Tremfya (guselkumab)
  

Janus kinase inhibitors (JAK inhibitors) can relieve joint pain and inflammation in PsA. These drugs inhibit enzymes linked to inflammation. When these are blocked, the body will stop producing inflammatory proteins that cause PsA symptoms.

Three JAK inhibitors are approved for autoimmune diseases: Xeljanz (tofacitinib), Olumiant (baricitinib), and Rinvoq (upadacitinib). Both tofacitinib and upadacitinib have been approved by the Food and Drug Administration (FDA) for treating PsA.   

People who experience severe PsA damage, as can occur with psoriatic AM, may need surgery to fix or repair damaged and deformed joints.

Physical therapy and regular exercise can increase joint and muscle strength, flexibility, and mobility.

Subtype Considerations

Asymmetric and symmetric PsA tend to be milder than the other subtypes of PsA. First-line therapies, including NSAIDs and low-dose corticosteroids, can help to reduce inflammation and manage other disease symptoms.

As time goes on, these types of PsA can progress and require systemic therapy or even surgical intervention. These subtypes can also evolve into the more aggressive types.

Treatment goals for psoriatic spondylitis aim to reduce inflammation, prevent joint damage, and reduce the need for spinal surgery. Much like DIP PsA and psoriatic AM, treatment needs to be aggressive.

If surgery becomes necessary, the process usually involves replacing entire joints (i.e., a knee or hip) or small joints of the vertebrae (the 33 individual, interlocking bones that form the spinal column) with metal, plastic, or ceramic materials.

The more severe types of PsA—DIP PsA and psoriatic AM—are treated more aggressively than asymmetric and symmetric PsA. The treatment goals for more severe types are to reduce pain and disability. Surgery ends up being the last option in some cases to alleviate severe pain and damage caused by DIP PsA or psoriatic AM.

Lifestyle and Home Remedies    

Home remedies and lifestyle changes can help manage PsA symptoms and improve treatment outcomes.  

Examples of home remedies to relieve PsA symptoms are:  

• Massage
• Heating pads to relax muscles and manage joint stiffness
• Cold packs to ease pain 

Lifestyle changes that can help manage PsA are:  

• Stretching and exercise to improve range of motion
• Stress relief exercises, including yoga and mediation
• Weight loss to reduce strain on joints
• Avoiding smoking or drinking too much alcohol
• Eating a diet low in sugar, fats, and salt

Summary  

Psoriatic arthritis (PsA) is a complex type of inflammatory arthritis that affects people differently. It is known for causing swelling, stiffness, redness, pain, and damage to joints, nails, and skin.

There are five subtypes of PsA characterized by the joints they affect. For example, distal interphalangeal psoriatic arthritis affects the joints in the fingers. It causes severe inflammation of the fingers and toes, while psoriatic arthritis mutilans can damage the hands, feet, fingers, and wrists.

People can have one kind of PsA and develop another subtype later on, when their disease progresses. Treatment for PsA will depend on the subtype, the severity of symptoms, what joints are affected, other PSA factors, and personal preferences. 

A Word From Verywell

Psoriatic arthritis outlook varies. Some people may have mild symptoms and experience few disease flare-ups, while others have more severe and debilitating symptoms. The more severe symptoms are, the more likely PsA will affect your mobility.  

Outlook can be affected by the type of joint involvement, diagnosis at a young age, psoriasis, and family history of psoriatic arthritis or psoriasis. You can improve your PsA outlook by following your treatment plan, including taking medications exactly as prescribed.