​Kembara Xtra - Medicine - Polymyalgia Rheumatica

​Kembara Xtra - Medicine - Polymyalgia Rheumatica 
A clinical syndrome that primarily affects people over 50 and is characterized by shoulder, hip, and neck pain and stiffness as well as morning stiffness and high inflammatory markers
Musculoskeletal; hematologic/lymphatic/immunologic system(s) affected
Synonym(s): pseudo-polyarthrite rhizomélique, polymyalgia rheumatica (PMR) syndrome, senile rheumatic illness
Aspects of Geriatrics
The likelihood rises with age (age > 50)
The typical onset age is 70 years.
Child Safety Considerations
uncommon in patients under 50. Between the ages of 70 and 80, PMR incidence peaks.


Epidemiology
Incidence After age 50, incidence rises. Incidence rates for PMR and giant cell arteritis (GCA) in the US are 50 and 18, respectively.
 Female predominates over male (2 to 3:1)
Peak incidence occurs between the ages of 70 and 80 and is most prevalent in Caucasians, particularly those of northern European heritage and in Scandinavia.
Prevalence
700/100,000 people over 50 years old are affected.

Pathophysiology and Etiology 

 Not known. Enhanced immune function and periarticular inflammation are related to the symptoms.
The pathogenesis
- Polygenic; incorporates numerous genetic and environmental variables
- A temporal artery specimen with histologic evidence of GCA and parvovirus B19 DNA showed a significant correlation.
Human leukocyte antigen determinants genetics (HLA-DRB1*04 and DRB1*01 alleles)

Risk factors include being older than 50 and having GCA.

Accompanying Conditions 

Concurrent GCA (temporal arteritis) occurs in 15–30% of patients, and women experience it more frequently than men.

Diagnoses: In elderly patients with recently developed proximal limb pain and stiffness (neck, shoulder, hip), suspect PMR.
Patients may alternately refer to both stiffness and pain. Most frequently, shoulder discomfort is present.
Symptoms frequently appear suddenly.
 Nighttime pain Can be unilateral, but soon becomes symmetrical Difficulty getting up from a chair or combing your hair (proximal muscle involvement)
 Excruciating morning stiffness
Carpal tunnel syndrome can be seen in 10-15% of patients, with systemic symptoms (fatigue, weight loss, and low-grade fever) occurring in 25% of cases.

clinical assessment 

 Reduced range of motion (ROM) in the hips, neck, and shoulders
 Muscle strength is typically normal, however it could be constrained by pain or stiffness.
 Tenderness of the muscles Disuse atrophy Tenosynovitis and synovitis of the tiny joints; unaffected feet and ankles Coexisting carpal tunnel syndrome


Differential diagnosis includes psoriatic arthritis, ankylosing spondylitis, rheumatoid arthritis (RA), palindromic rheumatism, systemic lupus erythematosus, Sjögren syndrome, and fibromyalgia.
(Consider aldolase and creatine phosphokinase.) Polymyositis-dermatomyositis
 Hyperparathyroidism, hypoparathyroidism, and thyroid disorders
Osteoarthritis, Rotator cuff syndrome, Hypovitaminosis D, adhesive capsulitis, and
Remitting seronegative symmetrical synovitis with pitting edema, or RS3PE syndrome,
 Myopathy (such as those caused by steroids, alcohol, or electrolyte depletion); Occult infection or malignancy (such as solid tumors, lymphomas, leukemia, or myeloma); Depression; fibromyalgia

Laboratory Results 

Criteria for ACR/EULAR classification:
Patients under 50 years old with bilateral shoulder pain, elevated C-reactive protein levels, or elevated ESR, with at least 4 points (without ultrasound) or 5 points (with ultrasound) from:
- More than 45 minutes of morning stiffness (2 points)
- Hip discomfort or limited mobility (1 point)
- Lack of anti-citrullinated protein antibodies (ACPAs) or rheumatoid factor (RF) (2 points)
- No other joint participation (1 point)
- If US is available, at least one hip with trochanteric bursitis or synovitis, and at least one shoulder with subdeltoid bursitis, biceps tenosynovitis, or glenohumeral synovitis (1 point each)
- If an ultrasound is available, both shoulders with biceps tenosynovitis, glenohumeral synovitis, or subdeltoid bursitis (1 point)
ESR (Westergren) elevation >40 mm/hr - ESR generally elevated, occasionally >100 mm/hr - ESR normal (40 mm/hr) in 7-22% of patients - Temporal artery biopsy if symptoms of GCA are present - Elevated C-reactive protein - Normochromic/normocytic anemia - Anti-cyclic citrullinated peptide (anti-CCP) antibodies usually
RF: negative (5–10% of individuals over 60 have a positive RF without RA).
 Mild increases in alkaline phosphatase levels in liver function tests Antibodies to ferritin peptide may be a helpful diagnostic sign.
Prednisone could affect test results.
Other conditions, such as infection, tumor, and renal failure, may elevate ESR.
 Regular EMG
Normal histology of the muscle
CK is consistently normal.
Initial examinations (lab, imaging)
 CBC, C-reactive protein, and ESR (typically >40 mm/hr)
Although MRI is not required for diagnosis, it may reveal bursitis, tenosynovitis, and periarticular inflammation.
Bursitis, tendinitis, and synovitis may be visible on the US.
PMR may be diagnosed with the aid of an MRI, PET scan, and temporal artery US.
The clinical diagnosis is supported by the ACR/EULAR categorization criteria (4).
Prior to treatment, an 18F-fluorodeoxyglucose PET scan enhances diagnostic precision.
 A scoring system was developed that included the following criteria: absence of RF and ACPA (2 points), absence of peripheral joint pain (1 point), morning stiffness for more than 45 minutes (2 points), hip pain/limited ROM (1 point).
A score of >4 indicates PMR with a 68% sensitivity and 78% specificity.
Temporal artery biopsy is a diagnostic procedure used on patients who have GCA-suggestive symptoms. Regard empirical research as pending.

Management 

 Address the risk of osteoporosis brought on by steroids.
- If necessary, get dual energy x-ray absorptiometry and evaluate your 25-OH vitamin D levels.
- For the treatment of corticosteroid-induced osteoporosis, take into account antiresorptive treatments (bisphosphonates).
Encourage daily intake of 800–1,000 IU of vitamin D and 1,500 mg of calcium.
 If necessary, physical therapy for ROM exercises


First Line of Medicine
Prednisone: 10 to 20 mg/day PO at first; a dramatic (diagnostic) response is anticipated in a matter of days. Almost all patients respond favorably to 15 mg/day.
- Possibly raised to 20 mg/day if no immediate reaction
- Rethink the diagnosis if there isn't a response to 10 to 20 mg/day after a week.
Divided-dose steroids (BID or TID) may seem helpful at first (particularly if symptoms return in the afternoon).
Consider using delayed-release prednisone, which may be more effective than immediate-release prednisone in treating morning stiffness.
● Start a gentle taper every two to four weeks by 2.5 mg reductions to a level of 7.5 to 10.0 mg/day. To avoid relapse, taper by 1 mg/month below this level.
Prednisone dosage should be increased (common) when symptoms return.
Treatment with corticosteroids frequently lasts several years.
 Could end after 6 to 12 months if there are no symptoms and a normal ESR.
A systemic fungal or bacterial infection, diabetes mellitus (or another immunocompromised state), and persistent heart failure are contraindications to using steroids. Treat any further infections.
 Safety measures
- Long-term steroid use (>2 years) is linked to weight gain, depression, osteoporosis, fractures, hypertension, cataracts, glaucoma, avascular necrosis, hypokalemia, worsening of chronic heart failure, and retention of sodium and water.
- Patients receiving low-dose corticosteroid therapy for PMR may experience temporal arteritis. Prednisone dosage must be increased (up to 40–60 mg) in order to treat this.
- Steroids taken on alternate days are ineffective.

Next Line

Regular adjunctive therapy usage is not advised
NSAIDs are typically insufficient for treating pain.
Although it hasn't been fully investigated in PMR, methotrexate somewhat lowers the cumulative dose of steroid therapy and lessens the rate of recurrence.
Case reports and brief studies have mentioned tocilizumab (6).
Anti-tumor necrosis factor (anti-TNF) therapies (infliximab, etanercept) are supported by inconsistent evidence.
Injections of corticosteroids (particularly for the shoulder) may assist to lessen discomfort and length of morning stiffness, enabling increasing levels of activity.

Patient Follow-Up Monitoring
Initial and taper evaluations are conducted monthly; thereafter, they are done every three months.
 Monitor ESR during steroid tapering; ESR and C-reactive protein should fall as symptoms become better.
Immediately seek medical attention if you experience GCA symptoms as headache, vision loss, or diplopia.
 Keep an eye out for the negative consequences of corticosteroid therapy, such as osteoporosis, hypertension, and hyperglycemia.
Do not treat an elevated ESR in asymptomatic patients; do not increase the dose of steroids to bring the ESR back to normal.

Diet: A balanced diet with enough calcium and vitamin D


Education of Patients 

Examine the negative consequences of corticosteroids.
Discuss the GCA symptoms (headache, vision loss, diplopia), and be prepared to present right away if any appear.
Follow up if symptoms return while tapering off steroids.
Do not stop using steroids suddenly.
 Make sure you get enough calcium and vitamin D.
Patient resources include:
- American College of Rheumatology: http://www.rheumatology.org/ Practice/ Clinical/ Patients/ Diseases_And_Conditions/ Polymyalgia_Rheumatica/ - Arthritis Foundation: www.arthritis.org

Prognosis The majority of patients need to take corticosteroids for at least two years.
If steroids are withdrawn too soon, exacerbation or relapse are frequently experienced.
The prognosis is excellent with the right care.
Relapse happens often (in 25–50% of cases).
A longer disease course and more flare-ups have been linked to older age at diagnosis, female sex, high baseline ESR, elevated levels of soluble IL-6 receptor, and high first steroid dose.

Exacerbation of disease with steroid taper; development of GCA (may occur while PMR is being appropriately treated); complications associated to continuous steroid use

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