00:00 / 00:00
of complete
of complete
Laboratory value | Result |
Sodium | 145 mmol/L |
Potassium | 3.7 mmol/L |
Chloride | 102 mmol/L |
Bicarbonate | 30 mmol/L |
2024
2023
2022
2021
with rheumatoid arthritis p. 472
rheumatoid arthritis p. 472
rheumatoid arthritis p. 472
rheumatoid arthritis p. 472
rheumatoid arthritis p. 472
rheumatoid arthritis p. 472
rheumatoid arthritis p. 472
rheumatoid arthritis p. 472
osteoarthritis/rheumatoid arthritis p. 472
rheumatoid arthritis p. 472
anemia of chronic disease and p. 427
autoantibody p. 113
azathioprine for p. 444
biliary cirrhosis p. 402
carpal tunnel syndrome and p. 452
celecoxib for p. 495
etanercept for p. 497
HLA-DR4 and p. 98
immunosuppressants p. 118
infliximab/adalimumab for p. 497
labs/findings p. 728
leflunomide for p. 495
methotrexate for p. 444
rituximab for p. 120, 446
uveitis p. 551
rheumatoid arthritis p. 472
rheumatoid arthritis p. 472
In rheumatoid arthritis, “arthr-“ refers to joints, “-itis” means inflammation, and “rheumatoid” comes from rheumatism, which more broadly refers to a musculoskeletal illness.
So, rheumatoid arthritis is a chronic, inflammatory disorder that mostly affects the joints, but can also involve other organ systems like the skin and lungs as well.
Alright, so a healthy joint typically has two bones covered with articular cartilage at the ends.
Articular cartilage is a type of connective tissue that acts like a protective cushion - a lubricated surface for bones to smoothly glide against.
One type of joint, like the knee joint is called a synovial joint.
A synovial joint connects two bones with a fibrous joint capsule that is continuous with the periosteum or outer layer of both bones.
The fibrous capsule is lined with a synovial membrane that has cells that produce synovial fluid and remove debris.
The synovial fluid is normally a viscous fluid like the jelly-like part of a chicken egg and it helps lubricate the joint.
To help serve these synovial cells, the synovial membrane also has blood vessels and lymphatics running through it.
Together, the synovial membrane and the articular cartilage form the inner lining of the joint space.
Rheumatoid arthritis is an autoimmune process that is typically triggered by an interaction between a genetic factor and the environment.
For example, a person with a certain gene for an immune protein like human leukocyte antigen, or HLA- DR1 and HLA–DR4, might develop rheumatoid arthritis after getting exposed to something in the environment like cigarette smoke or a specific pathogen like a bacteria that lives in the intestines.
These environmental factors can cause modification of our own antigens, such as IgG antibodies or other proteins like type II collagen or vimentin.
Τype II collagen and vimentin can get modified through a process called citrullination.
That’s when the amino acid arginine found in these proteins is converted into another amino acid, citrulline.
Meanwhile, due to the susceptibility genes HLA- DR1 and HLA–DR4, immune cells sometimes are not “clever” enough, so they get confused by these changes and they no longer recognize these proteins as self-antigens.
The antigens get picked up by antigen- presenting cells, and get carried to the lymph nodes to activate CD4+ T-helper cells.
Rheumatoid arthritis (RA) is a systemic inflammatory disorder of autoimmune origin that is primarily characterized by progressive, symmetric joint destruction, especially in the wrists and fingers, but may also affect other joints and many organs, such as the skin, heart, blood vessels, and lungs. Symptoms of RA include fatigue, joint pain, stiffness, and swelling, which can lead to decreased range of motion and joint deformity. RA is a chronic condition and treatment is focused on managing symptoms and preventing further joint damage. Treatment options include medications such as non-steroidal anti-inflammatory drugs (NSAIDs), disease-modifying antirheumatic drugs (DMARDs) and biologic agents, physical therapy, and in some cases, surgery.
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