Autoimmune Arthritis™ and Autoinflammatory Arthritis™ (AI Arthritis)refer to the type of inflammation-driven arthritis caused by autoimmune and autoinflammatory diseases. While the arthritis component unites these diseases, because they are autoimmune and autoinflammatory they affect more than just the joints.  The inflammation can affect tissues and organs, and can cause systemic, or whole body, symptoms as well.


In the past several years, research has shown that even the most common type of arthritis, degenerative or Osteoarthritis, does involve inflammation, but at much lower levels than the type associated with autoimmune and autoinflammatory diseases.  This is important to note, as the cause of these types of arthritis are very different, as is treating them.  A high majority of patients diagnosed with autoimmune or autoinflammatory diseases where the arthritis is a major component feel differentiating types is key to addressing issues surrounding awareness.



autoimmune vs. autoinflammatory - what's the difference?

The immune system is divided into two parts:  the “innate” and the “acquired” parts. As research into the immune system has advanced, some diseases once thought to be autoimmune (which stem from the acquired part) are now categorized as either autoinflammatory or as having autoinflammatory components (stemming from the innate part), and some even fall somewhere in between the two.

The “auto” is the commonality, which means "immune-mediated" (Reference 1).  So both Autoimmune and Autoinflammatory diseases have an immune system malfunction as the underlying cause of the symptoms, but because they are triggered by different parts, the underlying cause or mechanism of the diseases are different. This difference can affect treatment options, long-term health risks, and possible complications from the systemic inflammation (Reference 2).


Learn more about Autoimmune and Autoinflammatory Arthritis here.



diseases

While there are over 100 diseases that can include arthritis (various types), over 80 autoimmune diseases, and an additional several dozen autoinflammatory diseases, only a small percentage are either autoimmune or autoinflammatory with inflammation-driven arthritis as a clinical presentation either at onset or early disease ( < 12 months). We believe continued focus on the most “like” diseases is an important step towards identifying them early in onset, so that earlier detection, referrals, diagnosis, and treatment can begin. 


The following diseases that often present similarly, regardless of diagnosis:


  • Rheumatoid Arthritis (RA)
  • Psoriatic Arthritis (PsA)
  • Systemic Lupus Erythematosus (SLE)
  • Sjögren's Syndrome (SS)
  • Ankylosing Spondylitis (AS)
  • Axial Spondylitis (axSpA)
  • Adult Onset Still's Disease (AOSD)*
  • Juvenile Idiopathic Arthritis (JIA) 
  • systemic Juvenile Idiopathic Arthritis (sJIA)*


Learn about the common symptoms of these diseases here.


The average time to diagnose from onset ranges from 1-2 years in more common diseases, like Rheumatoid Arthritis, and up to 9 years for others, like Ankylosing Spondylitis.  IFAA continuously communicates with those affected with these diseases in order to further evaluate patient-reported early disease features, tracking both similarities and differences.  Our work will help expedite detection, referrals, and diagnosis.


When autoimmune and autoinflammatory diseases with inflammation-driven arthritis as a major component are not fully developed, or overlap so that a precise diagnosis cannot be determined, they are often given an "undifferentiated" diagnosis. These conditions often evolve into one of the above diseases; IFAA strongly advocates for early treatment intervention to prevent this progression.


  • Undifferentiated Connective Tissue Disease (UCTD), also sometimes called Undifferentiated Inflammatory Arthritis, Undifferentiated Polyarthritis, Seronegative Inflammatory Arthritis
  • Undifferentiated Spondyloarthropathy (USpA)



Other autoimmune and autoinflammatory diseases that may present with arthritis as a major clinical feature in early disease include:

  • Crohn's Disease 
  • Sarcoidosis
  • Relapsing Polychondritis 
  • Scleroderma (Systemic Scleritis)
  • Behcet's Disease
  • Palindromic Rheumatism 
  • Polymyalgia Rheumatica
  • Reactive Arthritis (ReA) formerly termed Reiter's Syndrome



Associated Diseases:

Diseases or conditions that often occur in conjunction with Autoimmune/Autoinflammatory Arthritis diseases:

  • Fibromyalgia
  • Dysautonomia
  • Raynaud's Phenomenon
  • Uveitis/Iritis
  • Vasculitis
  • Myositis/Polymyositis/Dermatomyositis

what kind of arthritis?

References:


1. Adamopoulos, I.E. "Autoimmune or Autoiflammatory? Bad to the Bone", International Journal of Clinical Rheumatology. Int J Clin Rheumatol. 2015;10(1):5-

2. Autoinflammatory Alliance. "Autoinflammatory vs. Autoimmune: What is the Difference?"   http://saidsupport.org/autoinflammatory-vs-autoimmune-what-is-the-difference, 2014.


Note:  Autoimmune/Autoinflammatory Arthritis is not a classification; it is a description to differentiate a cluster of diseases that are autoimmune and have arthritis involvement.  There are other types of arthritis, other than autoimmune/autoinflammatory or degenerative, such as gout.  There are also other types of autoimmune diseases that do not include arthritis.