Blood Tests for Joint Pain: What They Can Show

Joint pain is very common, and most of the time it comes from an injury, overuse or wear and tear arthritis (osteoarthritis). Sometimes, though, aching, stiff or swollen joints are a sign of an inflammatory condition such as rheumatoid arthritis, gout or an autoimmune disease, where early diagnosis and treatment make a real difference.

Blood tests can help tell these causes apart by looking for inflammation, specific antibodies and raised uric acid. No single test proves or rules out arthritis, so results are always read alongside your symptoms and an examination. This guide explains which blood tests can help with joint pain, which test to book first, what blood tests cannot show and when to get urgent help.

Test it in Chiswick: our Rheumatology Check blood test costs £79, with your result explained in person by a practitioner. No GP referral needed. Book this test or call 020 4515 0000.

Quick answer

The main blood tests for joint pain are inflammatory markers (CRP and ESR), rheumatoid factor and anti-CCP antibodies (for rheumatoid arthritis), uric acid (for gout) and vitamin D (low levels can cause bone and muscle pain). An ANA test is useful only when there are signs of a connective tissue disease such as lupus. A normal result does not rule out inflammatory arthritis: NICE advises urgent specialist referral for suspected persistent joint swelling (synovitis) even when these blood tests are normal.

Blood tests that can help

CRP and ESR: inflammation markers

C-reactive protein (CRP) and the erythrocyte sedimentation rate (ESR) rise when there is inflammation anywhere in the body. The NHS lists both as blood tests that help assess inflammation when rheumatoid arthritis is suspected. They are not specific to joints, as an infection or injury can also raise them, but a raised result alongside swollen, stiff joints points towards an inflammatory cause. Our CRP test (£49) and ESR test (£39) can be booked separately, or together with a full blood count and ferritin in the Inflammation Check (£79). Read more in CRP levels explained and ESR levels explained.

Rheumatoid factor

Rheumatoid factor is an antibody found in more than half of people with rheumatoid arthritis, according to the NHS. However, about 1 in 20 people without rheumatoid arthritis also test positive, so a positive result is not a diagnosis on its own. NICE recommends a rheumatoid factor test for adults with suspected rheumatoid arthritis who have joint swelling on examination. Our Rheumatoid Factor test (£49) measures it on its own.

Anti-CCP antibodies

Anti-CCP (anti-cyclic citrullinated peptide) antibodies are more specific for rheumatoid arthritis than rheumatoid factor. The NHS says people who test positive for anti-CCP are very likely to develop rheumatoid arthritis, and NICE advises considering the test when rheumatoid factor is negative. Book the Anti-CCP Antibodies test (£59) on its own or as part of a rheumatology panel.

Uric acid

Gout causes sudden, very painful, hot and swollen joints, often the big toe and often overnight. It happens when uric acid forms crystals in a joint. NICE uses a serum urate of 360 micromol/litre or more to support a diagnosis of gout. Uric acid can fall during a flare, so if it is below this level during an attack and gout is still suspected, NICE advises repeating the test at least 2 weeks after the flare settles. Our Uric Acid test (£39) is a simple way to check, and our guide to uric acid levels explains the result.

Vitamin D

Very low vitamin D can lead to osteomalacia (soft bones). The NHS lists swollen, painful wrists, pain in the back, shoulders, ribs, pelvis or legs, and weak muscles among its symptoms in adults. A Vitamin D test (£59) is worth including if your pain is widespread or achy rather than in one swollen joint. See vitamin D levels explained.

ANA (antinuclear antibodies)

ANA is a screening test for connective tissue diseases such as lupus and Sjogren's syndrome. It is best used when joint pain comes with other features, for example rashes, mouth ulcers, dry eyes or mouth, or Raynaud's. NHS guidance from Scotland notes that a low level positive ANA is found in 20 to 30% of healthy people, and up to 70% of people over 70, so it is not a good screening test for joint pain on its own. Our Antinuclear Antibodies (ANA) test (£99) is included in the Rheumatology Extended panel.

Ferritin

The NHS lists joint pain, especially in the fingers, as an early symptom of haemochromatosis, an inherited condition where iron builds up in the body. A Ferritin test (£49) is a simple first check if joint pain comes with tiredness or a family history of the condition.

Which test should I book?

• A focused start: Muscle and Joint Check, £59. Rheumatoid factor, uric acid, creatine kinase and LDH, a starting point for joint and muscle aches.
• A broader picture: Rheumatology Check, £79. ESR, rheumatoid factor, anti-CCP antibodies and uric acid, the core tests for inflammatory arthritis and gout.
• The fullest view: Rheumatology Extended, £179. Everything in the Rheumatology Check plus ANA and smooth muscle antibodies, useful when autoimmune disease is a possibility.

The rheumatology panels do not include CRP or vitamin D, so you may wish to add a CRP test or the Inflammation Check, and a vitamin D test.

What blood tests cannot tell you

Blood tests support a diagnosis but cannot make one. The NHS says no blood test can definitively prove or rule out rheumatoid arthritis. Osteoarthritis, the most common type of arthritis in the UK, is diagnosed from your symptoms and an examination, and blood tests are usually only used to rule out other conditions. Injuries, tendon and ligament problems, fibromyalgia and the perimenopause and menopause (lower oestrogen can cause aching joints) usually have normal blood results.

The most important finding in suspected inflammatory arthritis is joint swelling seen on examination. NICE recommends that any adult with suspected persistent synovitis of undetermined cause is referred for a specialist opinion, and that referral is urgent, even if CRP, ESR, rheumatoid factor and anti-CCP are normal, when:

• the small joints of the hands or feet are affected
• more than one joint is affected
• there has been a delay of 3 months or longer between symptoms starting and seeking medical advice

So if your joints are swollen, see your GP even if your private blood tests are normal. Our practitioner can provide a GP feedback report to take with you.

When to see a GP urgently

Ask for an urgent GP appointment or call NHS 111 if:

• you have joint pain and the skin around it is swollen and feels hot
• you have joint pain and feel generally unwell, have a high temperature or feel hot, cold or shivery (this can be septic arthritis, an infection in the joint)
• you have severe pain in one joint that started suddenly, or you find it difficult to move a joint
• you have stiffness in your shoulders or hips plus a new headache, scalp tenderness, jaw pain when eating or any change in your vision, as these can be signs of temporal arteritis, which needs treatment straight away

Go to A&E or call 999 if you have very bad joint pain after a fall or injury, cannot walk or put weight on a joint, your joint looks out of place, or you have tingling or no feeling around the joint after an injury.

Frequently asked questions

Can a blood test show arthritis?

Blood tests can show signs that point towards some types of arthritis, such as raised inflammation, rheumatoid factor, anti-CCP antibodies or high uric acid. They cannot diagnose osteoarthritis, and a normal result does not rule out inflammatory arthritis.

What does a positive rheumatoid factor mean?

It means the antibody was found in your blood. More than half of people with rheumatoid arthritis are positive, but so are about 1 in 20 people without it, so the result needs to be read with your symptoms, an examination and usually anti-CCP.

Is CRP high with joint pain?

CRP is often raised in inflammatory arthritis, gout flares and joint infections, and is usually normal in osteoarthritis. A normal CRP does not exclude inflammatory arthritis, so swollen joints still need assessing.

Can I have gout with a normal uric acid?

Yes. Uric acid can drop during a flare. NICE advises repeating the test at least 2 weeks after the flare has settled if gout is still suspected.

Should I have an ANA test for joint pain?

Only if your joint pain comes with other signs of a connective tissue disease. A low level positive ANA is common in healthy people, especially older adults, so testing without those signs can cause unnecessary worry.

Joint pain blood tests in Chiswick

Omnia Lifestyle is at 8 to 9 Bedford Corner, The Avenue, Chiswick, London W4 1LZ, a short walk from Turnham Green station (District line; Piccadilly line trains stop there early morning and late evening only) and served by buses 94, E3 and 272. Limited parking is available on request when you book. Every clinic test price includes your sample taken at the clinic, analysis at the Randox accredited laboratory, a practitioner review of your result with you, and a GP feedback report on request. You do not need a GP referral, and most results are back within a few working days.

Useful links: book the Rheumatology Check or Rheumatology Extended, add a CRP test, browse our autoimmune and inflammation blood tests, or compare every blood test and price. Our guides to CRP levels and uric acid levels explain these results in more detail.

This article is general information, not medical advice. Discuss your results with your GP or practitioner.