What is Psoriatic Arthritis?

What is Psoriatic Arthritis?

Psoriatic Arthritis (PsA) is a chronic inflammatory disease that affects both the skin and joints. It is associated with psoriasis, a condition characterized by red, scaly skin patches. PsA occurs when the immune system attacks healthy tissues, leading to joint inflammation, pain, swelling, and stiffness. Without treatment, PsA can result in joint damage and deformities.

Key Features of Psoriatic Arthritis:

• Autoimmune Condition: The immune system mistakenly attacks the joints and skin.
• Associated with Psoriasis: Most people with PsA have psoriasis; however, joint symptoms can precede skin symptoms in some cases.
• Varied Symptoms: PsA affects different parts of the body, including joints, tendons, and the skin.

Commonly Affected Areas:

• Joints: Hands, feet, knees, elbows, and spine.
• Tendons and Ligaments: Inflammation where tendons or ligaments attach to bones (enthesitis), often in the heels or soles.
• Nails: Nail changes, such as pitting, thickening, or detachment (onycholysis).

Symptoms:

1. Joint Symptoms:

   • Pain, swelling, and stiffness in one or multiple joints.
   • Morning stiffness lasting more than 30 minutes.
   • Asymmetrical or symmetrical joint involvement.

2. Skin Symptoms:

   • Scaly, red patches of psoriasis on the skin, often on the elbows, knees, scalp, or lower back.

3. Enthesitis:

   • Pain and tenderness where tendons and ligaments attach to bones, such as the Achilles tendon or plantar fascia.

4. Dactylitis ("Sausage Fingers or Toes"):

   • Swelling of an entire finger or toe due to joint and tendon inflammation.

5. Fatigue and Malaise:

   • Systemic inflammation may cause general tiredness and lack of energy.

6. Spinal Involvement (Axial PsA):

• Pain and stiffness in the lower back or neck.

Causes:

1. Immune System Dysfunction: PsA results from an overactive immune system attacking the joints and skin.
2. Genetics: A family history of Psoriasis or PsA increases the risk.
3. Environmental Triggers:
• Infections or injuries may trigger symptoms in genetically predisposed individuals.

Risk Factors:

• Psoriasis: About 30% of people with psoriasis develop PsA.
• Age: Typically develops between 30 and 50 years.
• Family History: Increased risk if close relatives have psoriasis or PsA.

Diagnosis:

1. Medical History and Physical Exam:

   • Assessing joint pain, swelling, and skin symptoms.

2. Lab Tests:

   • No specific test for PsA, but markers like C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) may indicate inflammation.
   • Tests to rule out other conditions (e.g., rheumatoid factor for rheumatoid arthritis).

3. Imaging:

• X-rays: To detect joint damage.
• MRI or Ultrasound: To identify inflammation in soft tissues.

Types of Psoriatic Arthritis:

1. Symmetric PsA:

   • Affects the same joints on both sides of the body (similar to rheumatoid arthritis).

2. Asymmetric PsA:

   • Affects different joints on each side of the body.

3. Distal Interphalangeal Predominant:

   • Affects the small joints of the fingers and toes near the nails.

4. Spondylitis:

   • Affects the spine and causes back pain and stiffness.

5. Arthritis Mutilans:

• A severe, deforming type of PsA that destroys bones and joints.

Treatment and Management:

While PsA cannot be cured, treatment focuses on reducing inflammation, relieving symptoms, and preventing joint damage.

1. Medications:

   • Nonsteroidal Anti-inflammatory Drugs (NSAIDs): To relieve pain and swelling.
   • Disease-Modifying Antirheumatic Drugs (DMARDs): E.g., Methotrexate, Leflunomide.
   • Biologics: Target specific parts of the immune system (e.g., TNF inhibitors, IL-17 inhibitors).
   • Corticosteroids: For severe inflammation, used cautiously to avoid side effects.

2. Physical Therapy:

   • Helps improve joint flexibility and strength.

3. Lifestyle Modifications:

   • Maintaining a healthy weight to reduce joint stress.
   • Regular, low-impact exercise like swimming or yoga.
   • Managing stress to reduce flares.

4. Skin Treatments:

   • Topical medications or phototherapy for psoriasis.

5. Surgery:

• Joint replacement in severe cases of joint damage.

Prevention:

• While PsA cannot be entirely prevented, managing psoriasis, avoiding joint injuries, and adopting a healthy lifestyle can reduce the risk of flares.

Early diagnosis and treatment are critical to managing PsA effectively and preventing irreversible joint damage.