An introduction to the clinical presentation of rheumatoid arthritis.

• Rheumatoid arthritis is introduced as a systemic disorder affecting multiple joints.
• Symptoms include symmetrical arthritis with pain, swelling, and nodules, particularly in the hands.
• Contrasts with osteoarthritis, which affects different joints.

A detailed look at how rheumatoid arthritis affects the joints, especially in the hands.

• RA commonly affects metacarpal phalangeal and proximal interphalangeal joints early in the disease.
• Typical deformities discussed include swan neck, boutonniere deformity of the thumb, and ulnar deviation.
• These deformities are explained in detail, illustrating the changes in joints and fingers.

Exploring the cellular-level changes in the joints due to rheumatoid arthritis.

• The structure of a typical joint and the role of the synovial membrane, synovial fluid, and cartilage are recapped.
• The process of synovitis in RA is described, leading to bone and cartilage erosion.
• Cells involved in RA include macrophages, fibroblast-like synoviocytes, T cells, plasma cells, and neutrophils.

Understanding how inflammation and immune cell migration contribute to the symptoms of rheumatoid arthritis.

• Cytokines from immune cells cause inflammation and joint damage.
• Activated fibroblast-like synoviocytes can migrate between joints, explaining symmetrical joint involvement.
• The role of T cells and B cells in promoting inflammation and bone erosion is discussed.

Examining potential causes and triggers that might lead to the onset of rheumatoid arthritis.

• While the exact cause of RA is unknown, several theories exist, including genetic and environmental factors.
• Autoantigen modifications, such as citrullination, may lead the immune system to attack the body's own tissues.
• The process of immune system activation, including antigen-presenting cells, T cell activation, and antibody production, is outlined.

Discussion on the key antibodies involved in rheumatoid arthritis and their implications.

• Rheumatoid factor (IgM) targets the IgG antibodies and forms immune complexes, present in 75% of RA cases.
• Anti-citrullinated protein antibodies (ACPA) are specific to RA and target proteins that have undergone citrullination.
• Both types of antibodies are significant in diagnosing RA and contribute to its pathophysiology.

Exploring how rheumatoid arthritis affects other organs and systems beyond the joints.

• Extra-articular manifestations result from cytokines produced by immune cells in the joints.
• Effects include skin nodules, liver inflammation, cardiovascular issues, neurological symptoms, musculoskeletal complications, and lung problems.
• These conditions can be worsened by RA treatments, such as glucocorticoids, which suppress the immune system.