Polymyalgia Rheumatica



Polymyalgia rheumatica is an inflammatory condition that causes pain and stiffness in the shoulders, pelvic girdle and neck. There is a strong association to giant cell arteritis and the two conditions often occur together. Both conditions respond well to treatment with steroids.

There are very good NICE clinical knowledge summaries on polymyalgia rheumatica. I suggest reading them before treating patients. This is a summary to help with your learning and revision.

 

Demographics

  • It usually affects old adults (above 50 years)
  • More common in women
  • More common in caucasians

Core Features

The NICE Clinical Knowledge Summary gives some core features that can be used to determine which patients may have PMR. These should be present for at least 2 weeks:

  • Bilateral shoulder pain that may radiate to the elbow
  • Bilateral pelvic girdle pain
  • Worse with movement
  • Interferes with sleep
  • Stiffness for at least 45 minutes in the morning

Other features:

  • Systemic symptoms such as weight loss, fatigue, low grade fever and low mood
  • Upper arm tenderness
  • Carpel tunnel syndrome
  • Pitting oedema

 

Differential Diagnosis

One of the key challenges is to exclude other conditions that can cause similar symptoms and not miss other diagnoses. The list of differentials is very long however some examples are:

  • Osteoarthritis
  • Rheumatoid arhtirits
  • Systemic lupus erythematosus
  • Myositis (from conditions like polymyositis or medications like statins)
  • Cervical spondylosis
  • Adhesive capsulitis of both shoulders
  • Hyper or hypothyroidism
  • Osteomalacia
  • Fibromyalgia

Diagnosis

Diagnosis is mainly based on the clinical presentation and the response to steroids. Other conditions need to be excluded in order to make a diagnosis of PMR.

Inflammatory markers (ESR, plasma viscosity and CRP) are usually raised however normal inflammatory markers do not exclude PMR.

The NICE clinical knowledge summaries advise a number of investigations prior to starting steroids to exclude other conditions:

  • Full blood count
  • Urea and electrolytes
  • Liver function tests
  • Calcium can be raised in hyperparathyroidism or cancer or low in osteomalacia
  • Serum protein electrophoresis for myeloma and other protein disorders
  • Thyroid stimulating hormone for thyroid function
  • Creatine kinase for myositis
  • Rheumatoid factor for rheumatoid arthritis
  • Urine dipstick

Additional investigations to consider:

  • Anti-nuclear antibodies (ANA) for systemic lupus erythematosus
  • Anti-cyclic citrullinated peptide (anti-CCP) for rheumatoid arthritis
  • Urine Bence Jones protein for myeloma
  • Chest xray for lung and mediastinal abnormalities

 

Treatment

Treatment of PMR is with steroids. The NICE CKS have clear guidelines on the steroid regime you should follow if treating patients. This is a summary to help your understanding.

Initially patients are started on 15mg of prednisolone per day.

Assess 1 week after starting steroids. If there is a poor response in symptoms it is probably not PMR and an alternative diagnosis needs to be considered. Stop the steroids.

Assess 3-4 weeks after starting steroids. You would expect a 70% improvement in symptoms and inflammatory markers to return to normal to make a working diagnosis of PMR.

If 3-4 weeks of steroids has given a good response then start a reducing regime with the aim of getting the patient off steroids:

  • 15mg until symptoms are fully controlled then
  • 12.5mg for 3 weeks then
  • 10mg for 4-6 weeks then
  • Reduce by 1mg every 4-8 weeks

If symptoms reoccur whilst on the reducing regime then they may need to increase the dose or stay on the dose longer before reducing again. It can take 1-2 years to fully wean off. If there is doubt about the diagnosis, difficulty controlling symptoms, difficult weaning steroids or steroids are required for more than 2 years refer to a rheumatologist.

Additional measures for patients on long term steroids. You can use the mnemonic “Don’t STOP”:

  • DON’T – Make them aware that they will become steroid dependent after 3 weeks of treatment and should not stop taking the steroids due to the risk of adrenal crisis if steroids are abruptly withdrawn
  • SSick Day Rules: Discuss increasing the steroid dose if they become unwell (“sick day rules”)
  • TTreatment Card: Provide a steroid treatment card to alert others that they are steroid dependent in case they become unresponsive
  • OOsteoporosis prevention: Consider osteoporosis prophylaxis whilst on steroids with bisphosphonates and calcium and vitamin D supplements
  • PProton pump inhibitor: Consider gastric protection with a proton pump inhibitor (e.g. omeprazole)

Last updated April 2019
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