How is Infectious arthritis / Septic arthritis diagnosed?

Infectious arthritis, also known as septic arthritis, is a condition characterized by joint inflammation caused by an infection. Prompt diagnosis is crucial to prevent further damage to the affected joint and to initiate appropriate treatment. The diagnostic process typically involves a combination of medical history evaluation, physical examination, laboratory tests, and imaging studies.

Medical history evaluation: The healthcare provider will inquire about the patient's symptoms, including joint pain, swelling, redness, and stiffness. They will also ask about any recent infections, surgeries, or injuries that may have contributed to the development of infectious arthritis.

Physical examination: The doctor will carefully examine the affected joint, assessing its range of motion, tenderness, warmth, and signs of inflammation. They may also check for signs of systemic infection, such as fever, rapid heart rate, and general malaise.

Laboratory tests: Blood tests are commonly performed to aid in the diagnosis of infectious arthritis. These tests may include:

• Complete blood count (CBC): Elevated white blood cell count may indicate an ongoing infection.


• C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR): Increased levels of these markers of inflammation suggest an active infection.


• Joint fluid analysis: A sample of fluid from the affected joint is obtained through a procedure called arthrocentesis. The fluid is then analyzed for the presence of bacteria, white blood cells, and other markers of infection.

Imaging studies: X-rays, ultrasound, or magnetic resonance imaging (MRI) may be ordered to assess the condition of the joint and to rule out other causes of joint inflammation. These imaging techniques can help identify joint damage, fluid accumulation, or signs of infection.

Once the diagnosis of infectious arthritis is confirmed, further tests may be conducted to determine the specific infectious agent responsible for the infection. This may involve culturing the joint fluid or blood samples to identify the bacteria or other microorganisms causing the infection.

It is important to note that the diagnostic process may vary depending on the individual case and the healthcare provider's judgment. Early diagnosis and prompt treatment are crucial to prevent complications and preserve joint function in cases of infectious arthritis.