Muscle Disease: Polymyalgia Rheumatica Flashcards
polymyalgia rheumatica
chronic inflammatory condiiton of unknown aetiology that affects elderly individuals (rarely seen under the age of 50)
where is incidence higher
norther regions
who does it tend to affect
elderly individuals - >50
presentation
- pain in the shoulder and hip girdle
- morning stiffness
- Mild polyarthritis, tenosynovitis and carpal tunnel syndrome
- There may be associated fever, weight loss, anorexia and depression
describe the distribution of symptoms
usually symmetrical
how do symptoms progress over the course of the day
tend to improve and also with movement
what problems may patients describe with their morning stiffness
difficult to get out of bed in the morning
is weakness a feature
no
length of onset
subacute - <2 weeks
differential diagnoses
- Sudden onset RA
- Polymyositis
- Hypothyroidism
- Primary muscle disease
- OA
- Occult malignancy or infection
- Bilateral subacromial impingement
GCA
a form of systemic vasculitis, causes granulomatous arteritis of the large vessels
GCA histology
transmural inflammation of affected arteries, and patchy infiltration by lymphocytes, macrophages and multinucleated giant cells
how does ischaemia occur in GCA
vessel wall thickening and subsequent arterial luminal narrowing
results in distal ischaemia
presentation of GCA
headache
visual disturbances - amaurosis fugax
scalp tenderness
tender, enlarged non pulsatile arteries
jaw claudication
fatigue, malaise, fever
what is amaurosis fugax
painless temporary loss of vision in both eyes
what should be consider as a DD if patient presents with GCA but it under 50
Takayasu’s arteritis
what should be done if GCA is suspected
- ESR
- start 60mg prednisolone immediately
- the risk is irreversible bilateral blindness
describe the headache in GCA
continuous
located in temporal or occipital areas
amaurosis fugax
painless temporary loss of vision in both eyes
sign of poor blood supply to optic nerve
permanent loss of vision occurs in 20% patients
what are the arteries like in GCA
tender, enlarged and non pulsatile
what can GCA result in in the arteries
- Can result in arteritic anterior ischaemic optic neuropathy (occlusion of optic nerve head circulation due to inflammation of posterior ciliary arteries)
- This results in sudden, profound visual loss, and irreversible bilateral blindness
what is one of the most significant causes of morbidity in GCA
visual loss - permanent in 20% patients
jaw claudication in GCA
- result of ischaemia of the maxillary artery
- Fatigue or discomfort of the jaw muscles during chewing of firm foods or prolonged speaking
when should GCA be considered
new onset headache in patient >50 with an elevated ESR, CRP or PV
diagnosis of PR and GCA
- diagnosis of exclusion
- raised inflammatory markers - ESR, PV, CRP
which is the most useful blood test
ESR
what is the most definitive test for GCA
temporal artery biopsy
- due to patchy involvement of artery, low sensitivity
CK levels
normal - distinguishing feature from PM and DM
what will a temporal artery biopsy show
mononuclear infiltration or granulomatous inflammation
multinucleated giant cells
treatment
Expect a rapid and dramatic response to steroids within one week, if not consider a DD
steroid doses
prednisolone 15mg OD for PR
prednisolone 40mg OD for GCA
when should steroids be started
as soon as diagnosis made
maintenance of treatment
- The prednisolone dose is reduced gradually over around 2 years. For the majority of patients, the condition will resolve over this period. Most need steroids for ≥2 years, so give gastric and bone protection
- Side effect of peptic ulceration – prescribe PPI, e.g. omeprazole
- Bisphosphonates, e.g. alendronate
role of NSAIDs and steroid sparing agents
there is no role
what must you tell patients (safety netting)
- Inform patients to seek urgent review if symptoms of GCA develop.
- GCA can lead to absolute blindness through bilateral central retinal artery occlusions or severely reduced vision with an anterior ischaemia optic neuropathy
