Diagnosing polymyalgia rheumatica

Diagnosing polymyalgia rheumatica (PMR) can often be quite a lengthy process that involves several different tests.

This is because the condition shares many symptoms with more common health conditions, such as Rheumatoid arthritis , which need to be ruled out first.

Tests

There's no specific test for polymyalgia rheumatica, but it's likely that a series of  blood tests  will be carried out.

Two blood tests erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) can be used to check the levels of inflammation in your body.

If the ESR and CRP test results are normal, its unlikely that polymyalgia rheumatica will be diagnosed because your doctor wont want to prescribe a long-term course of steroids if the diagnosis is uncertain. Sometimes, the ESR may be normal and CRP may be raised, which would be more likely to indicate a positive diagnosis. This is why both tests are usually carried out at the same time.

As inflammation is a characteristic of many conditions, high levels don't automatically mean that you have polymyalgia rheumatica. Further tests may be needed to help rule out other conditions that cause inflammation. For example, a test for rheumatoid factor and anti-CCP antibodies , may be carried out to rule out rheumatoid arthritis.

Blood tests can also help determine:

• whether there's an infection in your blood
• how well some of your organs, such as your kidneys, are working
• whether you have an overactive thyroid gland or an underactive thyroid gland (both conditions can cause muscle pain)

You may also have a urine test to check how well your liver is functioning.

X-rays and ultrasound scans may also be used to look at the condition of your bones and joints.

Symptom checklist

After other possible causes of your symptoms have been ruled out, a checklist can be used to see whether your symptoms match those most commonly associated with polymyalgia rheumatica.

A confident diagnosis of polymyalgia rheumatica can usually be made if you meet all of the following criteria:

• you're over 50 years of age 
• you have pain in your shoulders or your hips
• you have stiffness in the morning that lasts longer than 45 minutes
• your symptoms have lasted longer than two weeks
• blood tests show raised levels of inflammation in your body
• your symptoms rapidly improve after treatment with  corticosteroids

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