Inside Inflammatory Arthritis: JIA and RA

When I was diagnosed with juvenile rheumatoid arthritis (JRA), now known as juvenile idiopathic arthritis (JIA), I was just 18 months old. For over 25 years, I have only had a vague understanding of what unfolds within my body, my constant companion. JIA felt like my body's confusion, its tendency to turn against itself. It was simpler to accept JIA as my shadow, something I learned to walk alongside. Recently, that shadow evolved into something I yearned to understand. Why does my body go into this self-attack mode? How have the various medications I’ve taken throughout my life worked? JIA's presence is no longer just an obscure shadow; it's transformed into a puzzle I've been driven to solve. In today’s newsletter we will learn about inflammatory arthritis, untangling the differences between JIA and one of its adult counterparts, rheumatoid arthritis (RA). 

Inflammatory arthritis

The term arthritis refers to “painful inflammation and stiffness of the joints.” Inflammatory arthritis commonly presents with the typical signs of inflammation: pain, redness, warmth, swelling, and impaired function, although not all these symptoms may consistently manifest together. If left untreated, inflammatory arthritis leads to joint damage. Furthermore, it has the potential to impact various tissues, including the lungs, heart, eyes, skin, and other organs. Its systemic nature stems from its ability to influence the entire body.

Autoimmune inflammatory arthritis

Autoimmune inflammatory arthritis falls under the umbrella of inflammatory arthritis and encompasses various types, such as RA and JIA. While both involve joint inflammation, autoimmune inflammatory arthritis specifically involves the immune system mistakenly attacking the body's own tissues. This leads to chronic inflammation in the joints. On the other hand, inflammatory arthritis encompasses a wider range of conditions where joint inflammation occurs, including RA but also other non-autoimmune causes like gout.

JIA and RA's impact on joint health

In the autoimmune diseases, JIA and RA, the immune system attacks the body’s own tissues, particularly the synovium, which is the lining of the joints. The synovial fluid gathers immune cells like lymphocytes and macrophages, fueling ongoing joint inflammation and prompting the production of proinflammatory cytokines. These cytokines, released by immune cells, regulate various immune responses. Their imbalance leads to excessive inflammation, resulting in joint damage and related symptoms.

One cytokine, tumor necrosis factor (TNF), significantly influences the inflammatory process by promoting the production of other inflammatory substances. Overproduction of TNF in autoimmune inflammatory arthritis exacerbates persistent joint inflammation, ultimately leading to cartilage damage and bone erosion.

The combined effects of increased immune cell activity, heightened cytokine production, and chronic inflammation in the synovium contribute to the progression of JIA and RA, leading to joint pain, swelling, stiffness, and potential joint damage. Medications targeting these cytokines, like TNF inhibitors, aim to reduce inflammation and slow down joint damage in these conditions.

Juvenile Idiopathic Arthritis (JIA)

JIA is the most common form of arthritis in children and teens. Diagnosing it can pose a challenge since there's no single definitive test for confirmation. JIA encompasses several different subtypes, including systemic JIA, oligoarthritis, polyarthritis, enthesitis-related arthritis, and psoriatic arthritis. Physicians may suspect JIA when patients under 16 years old experience persistent, unexplained joint pain, stiffness, or swelling lasting six weeks or more. 

Doctors may request different blood tests to aid in diagnosing JIA. These tests might include checking for C-reactive protein (CRP), an inflammatory marker often elevated in children with JIA. Additionally, they might screen for autoantibodies, specific antibodies that attack one's own cells and tissues. Besides these, there are several other laboratory tests a doctor may prescribe to better understand the condition. Additionally, they might recommend imaging tests such as x-rays, ultrasounds, or MRIs to get a clearer view of the joints. These imaging techniques help in visualizing the affected areas and assist in identifying the specific type of JIA affecting the child. 

The renaming of juvenile rheumatoid arthritis to juvenile idiopathic arthritis (JIA) aimed to highlight that JIA isn't merely a pediatric version of the adult disease, RA. Unlike RA, JIA affects bone development and overall growth in children. Additionally, JIA comprises various chronic arthritis disorders. It embodies a collection of distinct diseases that develop differently in adulthood. For instance, in adulthood a patient with JIA might be reclassified as having RA or spondyloarthritis. 

Rheumatoid Arthritis (RA)

RA commonly affects areas like the hands, wrists, and knees—often on both sides of the body. It can extend its effects to various body parts such as the skin, eyes, lungs, heart, and blood vessels. While the exact cause of RA remains unclear, its far-reaching impact on various body parts, higher occurrence in women, and its usual onset between the ages of 30 and 60 underscore the complexity and significance of this chronic condition. In future newsletters, I'll delve deeper into RA to provide a more comprehensive understanding.

Closing Thoughts

Learning the complexities of autoimmune inflammatory arthritis, from the umbrella of inflammatory arthritis to the intricacies of JIA and RA, might feel overwhelming at times. But within this understanding lies immense power. Knowing the inflammatory processes within our bodies empowers us to fight back effectively and manage our symptoms.

By embracing knowledge and seeking support, you can adopt a proactive approach to managing your arthritis. Remember, you are not alone in this journey. Let's support one another, share our experiences, and continue to advocate for better understanding, treatment, and ultimately, a cure for all forms of arthritis.

Take good care,

Rebecca

Disclaimer: I am not a healthcare provider, and the information provided in this newsletter is intended for educational purposes only. The content shared here should not be used as a substitute for professional medical advice, diagnosis, or treatment. Always consult with your healthcare provider or physician for personalized guidance regarding any health concerns or medical conditions.

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