Did you know? Rheumatoid Arthritis and Gout are Different Diseases

Rheumatoid Arthritis and Gout are Different Diseases
Rheumatoid arthritis (RA) and Gout are distinct conditions.

Rheumatoid arthritis (RA): An autoimmune disease where the immune system mistakenly attacks its own proteins within the joints, treating them as foreign invaders.
Gout (Gouty arthritis): The immune system attempts to destroy uric acid crystals in the joint, which are indeed foreign substances.

The Root Causes
 Rheumatoid Arthritis (RA)
RA is caused by a genetic predisposition involving abnormal human leukocyte antigens (HLA), which are responsible for presenting pathogen proteins. This abnormality increases the risk of "mistakenly" presenting self-proteins to white blood cells.

The protein in question is a citrullinated protein (a protein modified with the amino acid citrulline). The immune system then attacks organs rich in this protein, primarily the joints. Furthermore, inflammation itself accelerates the production of this protein, leading to a vicious cycle of worsening joint inflammation.

Gout
Gout is caused by extremely high levels of uric acid in the body, typically due to the kidneys excreting less than normal. This is often combined with the consumption of foods that trigger high blood uric acid, such as alcohol and foods high in concentrated fructose. It is frequently associated with metabolic disorders like insulin resistance, which results in very high uric acid levels that enter the joints.

The uric acid forms crystals. White blood cells view these crystals as foreign, ingest them, and trigger an inflammatory response, leading to joint inflammation.

Joints Affected
 

 

Rheumatoid Arthritis (RA)
 RA typically targets joints with high levels of citrullinated protein, often affecting small joints, such as those in the fingers. However, it usually spares the distal interphalangeal (DIP) joints (the joints closest to the fingertip). It often appears symmetrically (on both sides simultaneously) because the immune system doesn't choose sides.

 Gout
 Gout often affects larger joints where uric acid is most likely to crystallize, such as the knee and the first metatarsophalangeal (MTP) joint (the joint at the base of the big toe). It is usually monoarticular (inflaming one joint at a time) because the crystallization process occurs randomly.