What is the Difference Between Reactive Arthritis and Rheumatoid Arthritis?

Reactive arthritis and rheumatoid arthritis are two different types of arthritis with distinct characteristics. Here are the main differences between the two:

Cause: Reactive arthritis is an autoimmune reaction to a bacterial infection, typically occurring within a month after a notable illness such as Chlamydia, foodborne infections, or a bowel infection. Rheumatoid arthritis, on the other hand, is caused by a combination of genetics, hormones, and environmental factors such as infection, smoking, and physical or emotional stress.
Seronegative status: Reactive arthritis is a seronegative spondyloarthropathy, meaning that people with this condition typically do not have specific antibodies called rheumatoid factor. Rheumatoid arthritis is not a seronegative spondyloarthropathy, and patients often test positive for rheumatoid factor.
Joint involvement: Both conditions can cause pain and swelling in the hands, feet, ankles, and knees. However, reactive arthritis often causes entire fingers and toes to swell, making them look like sausages, rather than just affecting the joint (e.g., knuckle). In rheumatoid arthritis, multiple joints are often involved at the same time, and often in a symmetrical pattern.
Inflammation: In rheumatoid arthritis, the lining tissue of the joint, the synovium, thickens and cells within it release chemicals that cause the signs of inflammation – swelling, redness, and heat. In reactive arthritis, the physical signs can be identical to those of rheumatoid arthritis, particularly in the knees.
Treatment: Both types of arthritis can be diagnosed through physical examination, blood tests, and imaging tests, and they are treated through specific medicines and surgeries. In rheumatoid arthritis, patients almost always need a "disease-modifying" medication, which can help control swelling, stiffness, and pain, as well as prevent joint damage.

On this page

Comparative Table: Reactive Arthritis vs Rheumatoid Arthritis

Here is a table comparing the differences between reactive arthritis and rheumatoid arthritis:

Feature	Reactive Arthritis	Rheumatoid Arthritis
Definition	Reactive arthritis is an aseptic inflammatory polyarthritis that usually follows nongonococcal urethritis and conjunctivitis.	Rheumatoid arthritis (RA) is a symmetric, inflammatory, peripheral polyarthritis of unknown etiology, typically leading to joint damage mediated by cytokines.
Causes	Reactive arthritis is precipitated by an infection at a distant site and genetic susceptibility.	RA is a chronic systemic autoimmune disease that primarily involves the joints.
Onset	Typically occurs one to three weeks following an infection, often with symptoms such as urethritis and conjunctivitis.	Onset is usually insidious, often beginning with systemic and joint symptoms.
Symptoms	Symptoms may include joint pain, swelling, and inflammation, as well as urethritis and conjunctivitis.	Symptoms may include joint pain, swelling, and inflammation, as well as systemic symptoms such as fatigue, malaise, and anorexia.
Diagnosis	Reactive arthritis is characterized by shared sacroiliitis, peripheral arthritis, and associated extra-articular lesions, and is typically associated with the HLA-B27 gene.	Diagnosis of RA is based on clinical presentation, synovial fluid examination, and imaging studies.
Treatment	Treatment may involve anti-inflammatory medications, antibiotics for infections, and physical therapy to help manage symptoms.	Treatment may involve nonsteroidal anti-inflammatory drugs, disease-modifying antirheumatic drugs, and biologic agents to control inflammation and prevent joint damage.

Please note that this table is based on the available information from the provided sources and may not cover all possible differences between reactive arthritis and rheumatoid arthritis.

Guilherme Mazui is graduated in journalism from the Federal University of Minas Gerais (UFMG) and a master's degree in Communication from the University of São Paulo (USP). In addition, he has experience in advertising writing and has worked as a content editor in several companies.