What is Inflammatory arthritis?
Inflammatory arthritis refers to a special group of arthritis caused by an abnormal immune response that can target the thin-cell layer lining many joints within our body (called synovium). There are different types of inflammatory arthritis.
What are the different types of inflammatory arthritis?
Rheumatoid arthritis
Rheumatoid arthritis is the most widely used example of Inflammatory arthritis. This is sometimes called seropositive arthritis (referring to a positive blood test for rheumatoid factor). It can affect different joints within the body, particularly the hands, wrists, neck, and back.
Seronegative arthritis
This is the other main group of inflammatory arthritis. It is characterised by a negative blood test for rheumatoid factor and is therefore called (seronegative). Probably, examples for this group include ankylosing spondylitis and psoriatic arthritis. Seronegative arthritis involves different joints and tendons within the body, particularly the lower back and sacroiliac joints.
Crystal arthropathy
This is a different group of arthritis due to the deposition of certain crystals within the joints, resulting in joint inflammation. The two main types are Gout (due to urate crystals deposition) and pseudogout (due to calcium pyrophosphate deposition). They tend to affect different large or small joints within our bodies, including the limbs and spine. The hand, wrist and feet can be particularly affected.
How to diagnose inflammatory arthritis?
Inflammatory arthritis is an autoimmune disease; therefore, the diagnosis usually requires a combination of clinical criteria (like joint pain and swelling), specific blood tests (inflammatory and autoimmune markers), and specific imaging findings.
Clinical findings
The clinical features of inflammatory arthritis depend on the type of arthritis. Rheumatoid and psoriatic arthritis, for example, tend to involve the small joints within the hand, wrist, and feet, resulting in joint pain, redness and swelling. This is called synovitis and indicates active inflammation of the special tissue lining the joint (synovium). Early morning stiffness is also a feature seen in inflammatory arthritis.
Inflammatory arthritis can cause inflammation of the soft tissues, including tendons. Inflammation of the finger tendons can lead to sudden swelling and pain throughout the entire finger, known as Dactylitis, commonly seen in psoriatic arthritis. Another symptom of inflammatory arthritis is tendon inflammation at their attachment points. This is called Enthesitis and can result in localised pain and swelling, for example, at the Achilles tendon attachment to the heel bone (calcaneum).
Seronegative arthritis tends to affect the spine and the sacroiliac joints more. The latter is called sacroiliitis, typically resulting in lower back pain. To learn more, please see our article about sacroiliitis.
Blood tests
These include general inflammatory markers like ESR and CRP, specific serological tests like autoimmune/vasculitis screen, rheumatoid factor, and anti-CCP antibodies. HLA-B27 test is usually positive in Ankylosing Spondylitis. Uric acid tests and crystal analysis from joint aspirate are useful in suspected crystal arthropathy, like gout.
Imaging
When it comes to diagnosing inflammatory arthritis, imaging is a crucial tool. X-rays are particularly useful for examining joints such as the hand and sacroiliac joints, where small areas of bone erosions can be detected. These are characteristics of inflammatory arthritis. Ultrasound assessment, including routine ultrasound and Doppler tests, is also highly beneficial. These tests are commonly used to evaluate small joints in the hands and feet when synovitis is suspected. Ultrasound is highly sensitive and can detect early changes, making it particularly useful in identifying mild inflammation that may be difficult to detect through clinical assessment (subclinical synovitis). MRI examination is sensitive to active inflammatory changes in joints and soft tissues. Whole spine and sacroiliac joints MRI are routinely performed in our practice when there is suspicion of seronegative inflammatory arthritis.
What is the treatment for inflammatory arthritis?
The treatment of inflammatory arthritis depends on many factors, including the type and severity of the condition. Nowadays, multiple medicines and treatment options can be used to control the disease. These are prescribed and managed by specialist doctors (rheumatologists).
Can steroids be used in the treatment of inflammatory arthritis?
Sometimes, a short course of oral steroids (tablets) is prescribed to control inflammation rapidly. In addition, if the inflammatory arthritis is under control but one or two joints are still inflamed, then an ultrasound-guided cortisone injection to that specific area can be an option. Steroids are potent anti-inflammatory medicines that work to reduce inflammation quickly. Ultrasound guidance ensures safe and accurate procedures. For more information on cortisone injections, please refer to our FAQs.
Other questions about inflammatory arthritis?
What is Dactylitis?
Dactylitis is a condition characterised by inflammation that causes redness, pain, and swelling in the fingers or toes. The inflammation usually affects the tendons or joints and is commonly called "sausage fingers.". This condition can be seen in association with inflammatory arthritis; therefore, further clinical assessment should be considered.
Mechanical back pain vs back pain due to inflammatory arthritis.
Mechanical back pain is the most common cause in our practice. This is caused by degenerative and arthritic changes in the discs and small joints of the back. Mechanical back pain typically gets worse towards the end of the day and after prolonged periods of activity. Inflammatory arthritis-type back pain, on the other hand, is less common, tends to be worse in the morning, and typically improves throughout the day. It's often accompanied by early morning stiffness. The above-mentioned blood and imaging tests are useful to differentiate the two conditions.
