Polymyalgia Rheumatica Flashcards
What is polymyalgia rheumatica? PMR
Not a true vasculitis and its pathogenesis is unknown.
It is a clinical syndrome that primarily impacts the elderly.
Who is affected in PMR?
Incidence increases with age
Average age of onset is around 70 years
It is very rare in < 50 yo
Peak incidence is between ages 70 to 80.
It is associated with GCA
Symptoms of PMR.
Subacute onset of proximal limb pain and stiffness.
The neck, shoulders and hips as well as lumbar spine can also be affected.
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
There might be some difficulty rising from chair or combing hair.
They might have systemic symptoms (25%) such as fatigue, weight loss, low-grade fever, anorexia and depression.
CTS can be a feature as well.
Findings on physical exam of PMR.
Decreased range of motion of shoulders, neck and hips.
Muscle strength is usually not affected, however it can be limited by pain and/or stiffness.
Muscle tenderness
Investigations of PMR.
CRP, ESR or PV elevated
ALP may be raised
Mild normochromic normocytic anaemia may be present
Temporal artery biopsy if symptoms of GCA as well.
Furthermore to exclude other dx…
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
How is a diagnosis of PMR made?
Mostly based on clinical history and examination as well as age.
Suspect polymyalgia rheumatica (PMR) in a person over 50 years of age presenting with at least 2 weeks of the core symptoms of:
Bilateral shoulder and/or pelvic girdle pain + morning stiffness >45 min.
A raised ESR and/or CRP becomes a hallmark of PMR.
What if history and examination suggests PMR but ESR and/or CRP are not raised?
Then consider differentials.
Non-elevated inflammatory markers are extremely rare.
Raised inflammatory markers are supportive of a diagnosis of PMR, although if the clinical picture and response to steroids are typical, the diagnosis can be made with normal inflammatory markers. (Says CKS)
Treatment of PMR.
Prednisolone 15mg PO OD. This is effective in almost all patients and is then tapered down very slowly.
Review after 1 week, no response? Probably not PMR
Methotrexate can be given if there is continuous relapse.
Most patients will need steroids for over 2 years so give bone protection as well.
How would you expect the patient to respond in terms of being given 15mg prednisolone?
They should have a dramatic improvement within 1 week.
If there is no dramatic response, what does this indicate?
That a differential should be considered.
Differentials of PMR.
Recent onset RA
Malignancy
Polymyositis
Hypothyroidism
Primary muscle disease
Infection
OA
Neck lesions
Reducing regime of steroid in PMR.
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
