What is the Difference Between Septic Arthritis and Rheumatoid Arthritis

The key difference between septic arthritis and rheumatoid arthritis is that septic arthritis is swelling and tenderness of joints in the body due to an infection caused by a germ such as a bacterium, while rheumatoid arthritis is swelling and tenderness of joints in the body due to an autoimmune disease.

Arthritis is a medical condition that causes swelling and tenderness of one or more joints in the body. The main symptoms of arthritis are joint pain and stiffness. There are different causes for arthritis. Based on these different causes, arthritis is classified as osteoarthritis, septic arthritis, rheumatoid arthritis, psoriatic arthritis, gout, and lupus.

CONTENTS

1. Overview and Key Difference
2. What is Septic Arthritis  
3. What is Rheumatoid Arthritis
4. Similarities – Septic Arthritis and Rheumatoid Arthritis
5. Septic Arthritis vs Rheumatoid Arthritis in Tabular Form
6. Summary – Septic Arthritis vs Rheumatoid Arthritis

What is Septic Arthritis?

Septic arthritis is the swelling and tenderness of joints in the body due to an infection caused by a germ such as bacteria. This infection can come from germs that travel through the bloodstream from another part of the body. This condition can also occur when a penetrating injury (animal bite or trauma) delivers the germs directly into the joints. Normally, septic arthritis is more likely to develop in infants and older adults. People who have artificial joints also have the risk of getting septic arthritis. Moreover, septic arthritis mainly affects the knee. But it can also affect hips, shoulders, and other joints. These infections can quickly and severely damage the cartilage and bone in the joints.

Figure 01: Septic Arthritis

The common symptoms may include discomfort and difficulty when using joints, swollen joints, redness and warmness in the affected area, fever, joint pain, loosening of joints, and dislocated joints. The cause of this medical condition includes infections by bacteria such as Staphylococci, Haemophilus influenzae, gram-negative Bacilli, Streptococci, Gonococci, and viruses. Furthermore, septic arthritis can be diagnosed through the removal of joint fluid and testing for bacteria, blood tests, phlegm tests, spinal fluid tests, and urine tests. The treatments may include draining pus from the joints through a needle, tube, or surgery, aspirin, ibuprofen, and naproxen for pain and fever, physical therapy to keep muscle strength, and fixing a splint on a joint to relieve pain.

What is Rheumatoid Arthritis?

Rheumatoid arthritis is the swelling and tenderness of joints in the body due to autoimmune disease. An autoimmune disorder occurs when one’s own immune system mistakenly attacks the own body’s tissues. Rheumatoid arthritis usually affects the lining of the joints. This causes a painful swelling that can eventually result in bone erosion and joint deformity.

Figure 02: Rheumatoid Arthritis

The signs and symptoms may include tender, warm, swollen joints, joint stiffness that worsens in the morning and after inactivity, fatigue, fever, and loss of appetite. Furthermore, about 40% of people may experience signs and symptoms in areas that don’t involve joints: skin, eyes, lungs, heart, kidneys, salivary gland, nerve tissue, bone marrow, and blood vessels. The diagnosis of this condition is carried out through physical examination, blood tests (checking for elevated erythrocyte sedimentation rate and C reactive protein), and imaging tests (X-ray, MRI). Treatments options for this rheumatoid arthritis include anti-inflammatory drugs such as NSAIDs and steroids, disease-modifying antirheumatic drugs such as conventional DMDRDs, biologic agents and targeted synthetic DMDRDs, physical and occupational therapy, and surgeries like synovectomy, tendon repair, joint fusion, and joint replacement.

What are the Similarities Between Septic Arthritis and Rheumatoid Arthritis?

  • Septic arthritis and rheumatoid arthritis are two different types of arthritis conditions.
  • Both conditions mainly affect the joints of the body.
  • These conditions have common symptoms such as tender, warm, swollen joints.
  • They are treatable with medications and surgeries.

What is the Difference Between Septic Arthritis and Rheumatoid Arthritis?

Septic arthritis is the swelling and tenderness of joints in the body due to an infection caused by a germ such as bacteria, while rheumatoid arthritis is the swelling and tenderness of joints in the body due to an autoimmune disease. Thus, this is the key difference between septic arthritis and rheumatoid arthritis. Furthermore, the incidence of septic arthritis is 7.8 per 100,000 persons in the USA and European countries. On the other hand, the incidence of rheumatoid arthritis is 40 per 100,000 persons in the USA and European countries.

The below infographic presents the differences between septic arthritis and rheumatoid arthritis in tabular form for side by side comparison.

Summary – Septic Arthritis vs Rheumatoid Arthritis

Septic arthritis and rheumatoid arthritis are two different types of arthritis conditions. Septic arthritis is the swelling and tenderness of joints in the body due to an infection caused by a germ such as bacteria, while rheumatoid arthritis is the swelling and tenderness of joints in the body due to autoimmune disease. So, this summarizes the difference between septic arthritis and rheumatoid arthritis.

Reference:

1. “Septic Arthritis.” Johns Hopkins Medicine.
2. “Rheumatoid Arthritis.” Mayo Clinic, Mayo Foundation for Medical Education and Research.

Image Courtesy:

1. “X-ray of septic arthritis of the hip” By Article authors: Ruiz Santiago, Fernando; Santiago Chinchilla, Alicia; Ansari, Afshin; Guzmán Álvarez, Luis; Castellano García, Maria del Mar; Martínez Martínez, Alberto; Tercedor Sánchez, Juan – (2016). “Imaging of Hip Pain: From Radiography to Cross-Sectional Imaging Techniques”. Radiology Research and Practice 2016: 1–15. DOI:10.1155/2016/6369237. ISSN 2090-1941. (CC BY 4.0) via Commons Wikimedia
2. “Rheumatoid arthritis — Smart-Servier (cropped)” By Laboratoires Servier – Smart Servier website: Images related to Rheumatoid arthritis, Skeleton and bones and Bones. (CC BY-SA 3.0) via Commons Wikimedia