Psoriatic Arthritis

Understanding Psoriatic Arthritis

Psoriatic arthritis (PsA) is a long-lasting, chronic immune-mediated disease characterized by inflammation and caused by the immune system malfunctioning. In PsA, the immune system attacks healthy cells and tissue in joints as well as causes overproduction of skin cells. PsA can start at any age but most often occurs between ages 30 and 50. One in three individuals with psoriasis also have PsA. For many, it starts about 10 years after psoriasis develops.

Symptoms of Psoriatic Arthritis

PsA can develop slowly with mild symptoms or quickly with severe symptoms. Some people may develop PsA in a joint after an injury. Genetics may play a role. There is little connection between psoriasis severity and PsA severity. A person could have few skin lesions, but many joints affected by arthritis. Common symptoms include:

• Fatigue
• Tenderness, pain and swelling over tendons
• Swollen fingers and toes that sometimes resemble sausages
• Stiffness, pain, throbbing, swelling and tenderness in one or more joints
• Decreased range of motion
• Morning stiffness and tiredness
• Nail changes, such as pitting or separation from the nail bed
• Redness and pain of the eye

Diagnosing Psoriatic Arthritis

There is no definitive diagnostic test for PsA. Seeking care from a rheumatologist is recommended. A rheumatologist specializes in the diagnosis and treatment of arthritis and other diseases of the joints, muscles, and bones. The diagnosis is made by the doctor’s observations and by a process of eliminating other conditions. The doctor may review the medical history, perform a physical examination, and tests such as blood tests, MRI, and X-rays.

Treating Psoriatic Arthritis

There is not a cure for PsA but there are treatments to help stop the disease progression, decrease pain, protect joints, and preserve range of motion. Even mild cases of PsA should be treated to prevent or limit the extensive joint damage that can occur in later stages of the disease. If left untreated, PsA can cause permanent joint damage, which may be disabling.

Non-drug treatment includes physical therapy, smoking cessation, weight loss and exercise. Drugs used to treat symptoms include nonsteroidal anti-inflammatories and oral or injected corticosteroids. There are many types of drugs used to treat the disease itself, including biologics. Biologic drugs target only specific parts of the immune system and may be taken orally or by injection (under the skin/subcutaneously or into the blood stream/intravenously). Tumor necrosis (TNF) inhibitor biologics are recommended as first-line treatment in active PsA and include infliximab (e.g., Inflectra^®, Remicade^®) administered intravenously and golimumab administered intravenously (Simponi Aria^®) or subcutaneously (Simponi^®). Ustekinumab (Stelara^®), a different type of biologic, may be prescribed under certain cases, and is administered subcutaneously.

Resources:

• Psoriatic arthritis - Symptoms and causes - Mayo Clinic
• Psoriatic Arthritis | Johns Hopkins Medicine

References:

• What Is Psoriatic Arthritis (PsA)?: National Psoriasis Foundation
• 2018 American College of Rheumatology/National Psoriasis Foundation Guideline for the Treatment of Psoriatic Arthritis