Polymyalgia rheumatica Flashcards
Definition
Clinical syndrome characterized by early morning stiffness and pain in the shoulder and pelvic girdles, lasting 30 minutes or longer.
It can occur either in isolation (most commonly) or in association with giant cell arteritis.
DDx with RA - small joints
+BUT ALSO IN ELDERLY EXCLUSIVELY, INITIAL MANIFESTATIONS CAN START AS POLYMYALGIA LIKE SHOULDER PAIN…
Epidemiology
Age >50y (average age at onset 73 years old)
F > M
More common in northern European countries and North America
Prevalence: ~60 per 100,000 (1 case for every 133 people over the age of 50 years).
Clinical Presentation
Joint pain
Shoulder pain (70-95%) + Hip and neck pain (50-70%):
Evaluate inflammation and effusion, not easy: we must use ultrasonography
Inflammatory type:
peak during the night
early morning stiffness lasting for >30 minutes
aggravated by active movements (but ameliorated by physical activity)
Initially unilateral then bilateral
Associated with non-erosive peripheral arthritis of knee and wrist (responds to GC, differential diagnosis → RA in elderly patients).
Systemic inflammation: Increased ESR and CRP
Rapid & complete response to glucocorticoids- this is a unique feature of polymyalgia rheumatica, while in other inflammatory arthropathies glucocorticoids can only improve the condition of the patient
Etiology
Multifactorial → interaction between genetic and environmental factors.
Genes: HLA-RB1 - related proteins
IL-1RN: SNP IL1RN2 of gene coding for IL-1 receptor antagonist → increased susceptibility
IL-6: 174 G/G SNP in promoter region → > serum levels → increased risk of disease relapse
ICAM-1: SNP 241 GG in association with HLA-DRB10401 → “”
Environmental factors (Molecular mimicry?)
Mycoplasma Pneumonia
Parvovirus B19
Chlamydia Pneumoniae
Pathogenesis
Peri-articular structures involvement → mild synovitis
macrophages and T cells CD4+ predominance
absence of B cells and no antibodies involvement
T lymphocytes and DC produce inflammatory cytokines, namely IL-6 and IL-2.
Increased expression of TLR-7 at the level of B and T cells and monocytes of PMR/GCA patients during active disease is seen.
Hypothesis on the hypothalamic pituitary axis 🡪 reduction of CORTISOL basal levels
Diagnosis
Clinical picture
Remission with GC
US
Shoulder: bilateral subacromial-subdeltoid bursitis
Hip: trochanteric bursitis
IN PATIENTS WITH NORMAL ESR AND CRP LEVELS, POSITIVE US CAN INCREASE THE PROBABILITY OF DIAGNOSIS
DDX
Elderly onset RA
Myalgia during viral infections
Polymyositis (CK normal)
Fibromyalgia
Shoulder Osteoarthritis
Endocrinopathies, like hypothyroidism
Parkinson Disease
Malignancy
Giant cell Arteritis
TX
Glucocorticoids!
Started at high dosage Prednisone
then slowly decrease until reaching complete remission
In patients who do not respond to glucocorticoids
*immunosuppressive drugs, like Methotrexate
*biological drugs (case report: etanercept and adalimumab)
DIAGNOSIS
Patients more than 50 years, pain at shoulder level with increased of ESR/CRP (exclusion of other possible diagnosis)1
-Morning stiffness duration >45 minutes
-Hip pain or limited range of motion
-Absence of RF or ACPA
-Absence of other joint involvement
-At least 1 shoulder with subdeltoid bursitis and/or biceps tenosynovitis and/or glenohumeral synovitis (either posterior or axillary) and at least 1 hip with synovitis and/or trochanteric bursitis
-Both shoulders with subdeltoid bursitis, biceps tenosynovitis, or glenohumeral synovitis
Major differences with Rheumatoid arthritis:
Large joints
No antibodies (even if in 30% of patients of RA do not have antibodies either)
GC lead to complete remission (in RA only symptom amelioration)
Start with 12.5/25 mg/day
Clinical improvement at 2-4 weeks?
Yes: Gradual tapering of GC –> REMISSION
YES: TAPER PREDNİSONE UNTİL DECONTİNUATİON
NO : REMISSION
No: Confirmation of PMR ???
