What is the Difference Between Septic Arthritis and Rheumatoid Arthritis?

Septic arthritis and rheumatoid arthritis are two different types of arthritis conditions that mainly affect the joints of the body. The key difference between the two lies in their causes:

Septic Arthritis: This condition is caused by an infection, usually due to bacteria, in one or more of the joints. Symptoms include intense pain, swelling, and limited range of motion in the affected joint. Septic arthritis can lead to severe complications if not treated promptly, and it may have a mortality rate of 7% to 15% despite the use of antibiotics.
Rheumatoid Arthritis: This condition is an autoimmune disease that causes swelling and tenderness of joints in the body due to an autoimmune response. Rheumatoid arthritis is more common, with an incidence of 40 per 100,000 persons in the USA and European countries.

Both conditions can present with tender, warm, and swollen joints, making it difficult to differentiate between the two without further investigation. However, the treatment approaches and potential complications are different, so it is essential to consult a healthcare provider for a proper diagnosis and treatment plan.

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What is the Difference Between Septic Arthritis and Rheumatoid Arthritis?

Comparative Table: Septic Arthritis vs Rheumatoid Arthritis

Septic arthritis and rheumatoid arthritis are two different types of arthritis conditions that mainly affect the joints of the body. Here is a table highlighting the differences between the two:

Feature	Septic Arthritis	Rheumatoid Arthritis
Cause	Infection, usually bacterial, such as Staphylococcus aureus or Streptococcus species	Autoimmune disorder, where the immune system attacks healthy joints
Symptoms	Pain, swelling, warmth, and redness in the affected joint(s)	Pain, swelling, and tenderness in multiple joints
Diagnosis	Blood tests (elevated erythrocyte sedimentation rate and C-reactive protein), imaging tests (X-ray, MRI), and synovial fluid analysis	Blood tests, imaging tests (X-ray, MRI), and physical examination
Treatment	Antibiotics, arthrocentesis (joint aspiration), and sometimes surgical methods to evacuate purulent material	Anti-inflammatory drugs (NSAIDs), disease-modifying antirheumatic drugs (DMARDs), physical and occupational therapy, and surgeries like synovectomy, tendon repair, joint fusion, and joint replacement
Risk Factors	Age older than 80 years, diabetes mellitus, rheumatoid arthritis, recent joint surgery, hip or knee prosthesis, skin infection, and intravenous drug abuse	Previous history of rheumatoid arthritis or other inflammatory arthritis, immunosuppressive medication use, and anti-tumor necrosis factor therapy

It is essential to diagnose septic arthritis promptly, as it can lead to rapid joint destruction if left undetected. A high suspicion for septic arthritis should be maintained, especially in patients with a history of rheumatoid arthritis or other inflammatory arthritis.

Guilherme Mazui

Guilherme Mazui is graduated in journalism from the Federal University of Minas Gerais (UFMG) and a master's degree in Communication from the University of São Paulo (USP). In addition, he has experience in advertising writing and has worked as a content editor in several companies.