Polyarthritis, Inflammatory Arthritis, and Rheumatoid Arthritis

How They Are Related—and How They Differ

The terms "inflammatory polyarthropathy,' "inflammatory arthritis," and rheumatoid arthritis" (RA) are often used interchangeably. While they are related, they don't mean the same thing. RA is a disease, while the other two are ways of describing a particular case of arthritis (how many joints are affected and the genesis of the disease).

The word "polyarthropathy" literally means "disease in many joints." It's used in the same context as "polyarthritis" (inflammation in many joints).

Comparison of polyarthritis, inflammatory arthritis, and rheumatoid arthritis.

Verywell / Hugo Lin

Inflammatory Polyarthropathy

Inflammatory polyarthropathy/polyarthritis is defined as arthritis that affects four or more joints. It's not a type of arthritis and can be applied to many types of arthritis in which the disease process is driven by inflammation.

Conditions that can cause polyarthropathy include: 

Treatments and the prognosis for polyarthropathy depend on the condition causing it.

From Acute Illness

Polyarthritis isn't only tied to chronic illnesses. It also can be a transient symptom of a passing illness such as rheumatic fever.

Inflammatory Arthritis

The term inflammatory arthritis typically refers to arthritis due to autoimmune disease in multiple joints throughout the body. In autoimmune disease, your immune system misfires and attacks the body's own tissues. The damage it causes leads to inflammation.

An exception is gout, which is classified as inflammatory but isn't autoimmune.

Arthritis caused by inflammation is often associated with joint pain and stiffness, especially after periods of rest or inactivity, such as in morning stiffness. Swelling, redness, and warmth may surround the affected joints.

Types of inflammatory arthritis include:

As with inflammatory polyarthropathy, treatments and outcomes for inflammatory arthritis depend on the specific diagnosis.

Inflammatory arthritis may also be associated with systemic effects such as fatigue, fever, rash, and organ involvement.

Rheumatoid Arthritis

Rheumatoid arthritis is a specific disease that is, by definition, a type of inflammatory polyarthritis. It's an autoimmune disease that typically involves many joints symmetrically (the same joint on both sides of the body) and may be associated with systemic effects.

In RA, the immune system attacks the lining of the joint (called the synovium) and causes inflammation, which leads to joint damage. Without treatment, this disease can lead to serious disability.

Early and aggressive treatment of rheumatoid arthritis can help prevent joint damage from inflammation. Disease-modifying anti-rheumatic drugs (DMARDs) and biologic drugs, often used in combination, are common parts of the treatment regimen.

TNF blockers, which are a type of biologic drug, effectively reduce chronic inflammation, decrease mortality, and reduce the risk of cardiovascular events in people with this disease.

Rheumatoid Arthritis Doctor Discussion Guide

Get our printable guide for your next doctor's appointment to help you ask the right questions.

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Polyarthropathy vs. Inflammatory Arthritis vs. Rheumatoid Arthritis: Key Differences

While there's some overlap in the definitions, these terms mean different things.

Inflammatory polyarthropathy/polyarthritis:

  • Affects four or more joints
  • Is a description of arthritis, not a type
  • Is tied to chronic and acute illnesses
  • Doesn't imply systemic symptoms (although many inflammatory polyarthropathies involve them)
  • Treatment depends on underlying illness

Inflammatory arthritis:

  • Affects multiple joints
  • Is a description of arthritis, not a type
  • Is tied to autoimmune and inflammatory disease
  • May involve systemic symptoms
  • Treatment depends on underlying illness

Rheumatoid arthritis:

  • A type of autoimmune/inflammatory arthritis
  • Affects the lining of many joints
  • Can be described as inflammatory polyarthropathy or inflammatory arthritis
  • May involve systemic symptoms
  • Treatments include DMARDs and biologics

If your healthcare provider is using one of the above terms and you don't understand what it means in relation to your symptoms or diagnosis, be sure to ask. The better you understand what's going on in your body, the better armed you are to manage it, alleviate symptoms, and improve your quality of life.

Frequently Asked Questions

  • Is inflammatory polyarthropathy curable?

    It depends. When inflammatory polyarthropathy comes on as part of an infectious disease, yes, it's curable. It'll likely go away when the underlying illness clears up.

    Inflammatory polyarthropathy that's from autoimmune or inflammatory arthritis isn't considered curable. You may be able to find treatments that effectively manage it, though.

  • Is inflammatory polyarthropathy the same as rheumatoid arthritis?

    No, these terms don't mean the same thing. Inflammatory polyarthropathy isn't a disease, but a descriptive term meaning pain and inflammation in more than five joints.

    Rheumatoid arthritis is a type of autoimmune arthritis. Because it generally affects multiple joints, it's often described as an inflammatory polyarthropathy.

  • Is inflammatory polyarthropathy chronic?

    Not always. How long it lasts depends on the illness that triggered it. If your joint pain is related to an infectious disease like rheumatic fever, it likely won't become chronic.

    If it's tied to a type of arthritis, which is a chronic illness, inflammatory polyarthropathy will likely be chronic unless treatments eliminate pain in enough joints that the description no longer fits.

5 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Alpay-Kanıtez N, Çelik S, Bes C. Polyarthritis and its differential diagnosisEur J Rheumatol. 2018;6(4):167-173. doi:10.5152/eurjrheum.2019.19145

  2. Shankar B, Bhutia E, Kumar D. Atypical arthritis revisited: Acute rheumatic feverAnn Pediatr Cardiol. 2016;9(2):164-166. doi:10.4103/0974-2069.180670

  3. Arthritis Foundation. Tracking disease activity in inflammatory arthritis.

  4. Hospital for Special Surgery. Inflammatory arthritis.

  5. Merck Manual Professional Version. Rheumatoid arthritis (RA).

Additional Reading

By Carol Eustice
Carol Eustice is a writer covering arthritis and chronic illness, who herself has been diagnosed with both rheumatoid arthritis and osteoarthritis.