Rheumatoid Arthritis Overview

Inflammation of the synovial membrane in joints, characterized by synovial hyperplasia (overgrowth) and edema, forming a thick, destructive layer called "pannus."

Autoantibodies that target citrullinated proteins, commonly found in patients with rheumatoid arthritis (RA).

An autoimmune disease characterized by chronic inflammation of the joints, primarily affecting small and medium-sized joints. It can also affect large joints like the knee, and often leads to joint destruction and disability.

A type of autoantibody found in the blood of individuals with rheumatoid arthritis (RA), which targets the Fc portion of immunoglobulin G (IgG).

The condition where the presence of rheumatoid factor (RF) and/or anti-citrullinated protein antibodies (ACPA) in the blood can be detected years before clinical symptoms of rheumatoid arthritis (RA) appear.

Cigarette smoking has been strongly associated with an increased risk of developing rheumatoid arthritis (RA).

Periodontal infections, especially those caused by the bacteria Pseudomonas gingivalis, have been linked to an increased risk of developing rheumatoid arthritis.

Patients with rheumatoid arthritis (RA) have a higher risk of developing cardiovascular problems, including heart attacks and strokes, compared to the general population.

Autoimmune disease occurs when the immune system mistakenly attacks the body's own tissues. The exact cause of this breakdown in tolerance is unknown, but it can trigger years before clinical symptoms.

Anti-citrullinated protein antibody (ACPA) is incredibly specific to RA, meaning it's almost always found in patients with RA. However, it's not highly sensitive, being present in only 80% of RA cases.

Citrullination is a process that converts arginine into citrulline, a modified amino acid. It typically occurs in dying cells and can be triggered by environmental factors like smoking.

Based on the presence of auto-antibodies, RA patients are categorized as either seropositive (testing positive for RF, ACPA, or both) or seronegative (lacking these auto-antibodies despite showing clinical RA characteristics). About 25% of RA patients fall into the seronegative category.

Anti-carbamylated protein antibody (Anti-CarP) is a recently discovered antibody that targets carbamylated proteins, a form of protein modification different from citrullination.

Cyanate is a chemical that can increase NETosis, a process where dying cells release their DNA. Anti-CarP antibodies are found in about 45% of RA patients and are more common in seronegative cases.

Rheumatoid arthritis (RA) begins outside of the joints, even though its most well-known effects are on the joints. This means the disease process starts in other parts of the body before affecting the joints.

A genetic factor associated with increased risk of Rheumatoid Arthritis (RA), specifically the HLA-DRB1 gene with a particular 5 amino acid sequence (shared epitope).

An enzyme that converts arginine to citrulline, found in Porphyromonas gingivalis, promoting inflammation and citrullination of proteins in the mouth.

A type of RA where antibodies (RF and ACPA) are not found in the blood, even though the condition is a type of autoimmune disease.

A chronic inflammatory disease that infects about 10% of the population, characterized by gum inflammation and bone erosion. It shares similarities with RA and can be aggravated by smoking.

A thick layer of cells that lines the joint cavity, composed of fibroblasts and macrophages. In RA, this layer becomes hyperplastic and hypertrophic, contributing to joint inflammation.

A process that occurs in RA, where the synovial membrane becomes thicker (more than 10 layers) due to an increase in cells and blood vessels.

Erosion in rheumatoid arthritis (RA) refers to the breakdown of bone and cartilage in affected joints. It is caused by the pannus, a layer of inflamed tissue that forms around the joints.

Erosion in RA develops rapidly in the early stages, often within the first 6 months of disease onset. This rapid progression can lead to significant joint damage and disability.

Preventing erosion in RA is crucial for preventing disability. Early diagnosis and timely treatment with disease-modifying drugs, including biological therapies, can significantly slow down and even prevent erosion.

In the early stages of RA, symptoms like pain, morning stiffness, and swollen joints are caused by inflammation, not erosion. However, over time, erosion leads to irreversible joint damage and deformities.

Boutonnière deformity is a finger deformity characterized by flexion of the PIP joint (middle knuckle) and hyperextension of the DIP joint (end knuckle).

Swan neck deformity is a finger deformity characterized by flexion of the DIP joint (end knuckle) and hyperextension of the PIP joint (middle knuckle).

Triangle feet is a foot deformity associated with RA, characterized by plantar subluxation of the metatarsal heads (bones in the midfoot). This can lead to instability and pain.

Pulmonary manifestations in RA include interstitial lung disease, which can lead to fibrosis (scarring) of the lungs. This can be detected by auscultation, where a Velcro sound indicates fibrosis and requires further investigation with a CT scan.

Ground glass opacity on a chest X-ray indicates inflammation and cellular infiltrate in the alveolar spaces, but no permanent damage. This can be reversible with treatment.

Honeycombing on a chest X-ray indicates fibrosis, which is irreversible damage to the lungs.

Rheumatoid lung nodules can be found in patients with rheumatoid arthritis. In smokers, these nodules can also be cancerous. Multiple nodules suggest an underlying disease, while a solitary nodule is more likely to be cancerous.

In patients with rheumatoid arthritis, nodules can develop cavities, predisposing them to mainly fungal infections, such as aspergillosis. It's important to rule out other causes of cavitation, like tuberculosis and staphylococcus pneumoniae.

Rheumatoid arthritis can cause inflammation of small blood vessels, leading to small signs of vasculitis.

Scleritis is a serious inflammation of the white part of the eye, causing redness and pain, and requiring immediate treatment.

Felty's syndrome is a rare variant of rheumatoid arthritis that includes chronic arthritis, enlarged spleen, and low white blood cell count.

Patients with rheumatoid arthritis are at an increased risk of heart disease, such as heart attacks, strokes, and heart failure, due to accelerated atherosclerosis.

Tests that assess general health status and can reveal information about specific conditions like anemia and inflammation. Common examples include complete blood count (CBC), inflammatory markers like CRP and ESR, and kidney function test (creatinine).

An autoimmune disease characterized by chronic inflammation of the joints, leading to pain, swelling, stiffness, and joint damage over time. It primarily affects the small and medium-sized joints, but can also affect larger joints.

A type of X-ray used to visualize the bones and joints, revealing erosions and narrowing of joint space. It is a crucial tool for assessing the extent of disease and monitoring its progression.

A more advanced imaging technique that uses X-rays and a computer to create detailed 3D images of the bones and joints. CT scans are particularly useful for detecting bone erosions that may not be visible on standard X-rays.

A non-invasive imaging technique that uses sound waves to create images of the soft tissues, including the joints. Ultrasound is particularly useful for assessing inflammation (synovitis) and monitoring the effectiveness of treatment.

This type of arthritis is caused by psoriasis, a skin condition. It can affect the joints similarly to rheumatoid arthritis but often affects specific joints like the fingers, toes, and spine.