Med-Surg: Chapter 20: Connective Tissue Disorders: Rheumatoid Arthritis Flashcards
Epidemiology
- affects 1% of population
- females 3x more likely to get it than males
- genetics and environmental factors play a key role in development
Risk factors
- first degree relatives with hx of RA
- cigarette smoke
- bacteria
- viruses
Pathophysiology
-is a chronic, systemic, autoimmune inflammatory disease characterized by an inflammatory process that affects diarthrodial, or freely moving, joints, causing pain and swelling
-involved joints are distributed in a symmetrical fashion, meaning bilateral wrists, ankles, or knees
-primarily targets the synovial membrane
-an unknown antigen triggers an immune response, leading to synovial tissue damage
-the immune system fails to distinguish self from “non-self” and causes destruction to the synovium of joints
-inflammation of the synovium may lead to a dramatic increase in synovial fluid, impairing movement and causing pain
-the synovial membrane becomes thickened and promotes destruction of the joint
>in this process, antigens (substances that trigger an immune response in order to rid the body of that substance) activate monocytes and T lymphocytes; then immunoglobulin antibodies form immune complexes with antigens. Phagocytosis of the immune complexes generates an inflammatory reaction. Leukotrienes and prostaglandins are produced as a result of phagocytosis. Leukotrienes attract additional WBCs, and prostaglandins modify inflammation
-Collagenase, an enzyme that breaks down collagen, is also produced by leukotrienes and prostaglandins, leading to edema, proliferation of synovial membrane and pannus formation (a layer of vascular fibrous tissue), destruction of cartilage, and erosion of bone
Clinical Manifestations
-joint pain
-joint swelling
-erythema
-morning stiffness (longer than 30 minutes)
-fatigue
>onset is often insidious, with vague complaints of joint and muscle pain that evolves into joint pain with synovitis, inflammation of the synovial membrane, and can lead to joint destruction and deformity
Joint Deformities
if left untreated or inadequately treated, leads to irreversible joint damage and disability
- swan-neck deformity caused by hyperextension of the proximal interphalangeal joints
- boutonniere deformity caused by abnormal flexion of the proximal interphalangeal joints
- ulnar deviation caused by the lateral deviation of the phalanges
Rheumatoid nodules
may be formed in subcutaneous tissue over bony prominences
-nodules mobile and nontender
Extra-articular (outside of the joint) clinical manifestations
- Osteopenia (decreased bone density)
- Muscle weakness
- Episcleritis (red, painful inflammation of the episclera without discharge)
- Scleritis (inflammation of the sclera, which produces deep ocular pain)
- Pleuritis (inflammation of the lining surrounding the lungs)
- Pleural effusion (excess fluid accumulation around the lungs)
- Pericarditis (inflammation of the fibrous lining that surrounds the heart)
- An enlarged spleen
- Anemia
How do Patients typically present?
- peripheral joint pain, which is usually symmetrical
- complain of morning stiffness lasting greater than 30 minutes
- symptoms persist 6 weeks or longer
- synovitis; tenderness and synovitis are assessed by palpating each joint individually
Comparing Osteoarthritis and Rheumatoid Arthritis
> Osteoarthritis
- morning stiffness less than 30 minutes
- not immune mediated
- joint involved: large weight-bearing joints such as hips and knees; PIPs, DIPs, CMC, First MTP, previously injured joints
- symmetrical joint involvement: not typical
- systemic organ involvement: no
> Rheumatoid Arthritis
- morning stiffness more than 30 minutes
- immune mediated
- joint involved: MCPs, PIPs, MTPs, wrists, elbows, ankles, knees
- symmetrical joint involvement: yes, very typical
- systemic organ involvement: yes
Radiographs
conventional radiographs used to assess for bony erosions and joint-space narrowing
- may be repeated during treatment to assess for disease progression and efficacy of pharmacological therapy
- MRI may detect erosions not detected by conventional radiographs
- Ultrasonography used to assess for synovitis and erosions not detectable by plain radiographs and good option for pts who refuse MRI b/c of cost or claustrophobia
Nonpharmacological Therapy
- education about disease and management of disease
- range-of-motion exercise to promote joint mobility, reduce stiffness, and improve muscle strength
- aerobic exercise promotes cardiac health
- physical and occupational therapies to teach appropriate exercises, how to protect joints, evaluate need for assistive devices, and proper use of devices
- proper nutrition to maintain good health, prevent obesity, and decrease risk of heart disease
- take rest periods to manage fatigue and joint pain
Pharmacological management
Goal= control the inflammation that leads to joint and tissue destruction, decreasing joint pain, synovitis, and stiffness, as well as maintaining joint function and preventing joint destruction
>analgesics, NSAIDS, and glucocorticoids:
-analgesics including acetaminophen and narcotic agents, provide only pain relief with no alteration in disease process
-anti-inflammatory medications provide pain relief and some reduction in inflammation but do not alter disease process
-glucocorticoids (prednisone) may be given orally IM< intra-articularly, or IV and can suppress inflammation and later the disease process but are not safe at high doses over long periods of time
>if disease does not respond to combination of analgesics, anti-inflammatory agents, and low dose prednisone, they are treated with disease-modifying antirheumatic drugs (DMARDs)
Disease-Modifying Antirheumatic Drugs (DMARDs)
- methotrexate (Rheumatrex)
- leflunomide (Arava)
- hydroxychloroquine (Plaquenil)
- sulfasalazine (Azulfidine)
- Tofacitinib (Xeljanz)
> each alters the immune system in various ways, altering the inflammatory response to decrease inflammation and slow disease progression
may be used alone as monotherapy or in conjunction with one another
before use, inform provider of hx or exposure to active tuberculosis
Safety Alert: Methotrexate
- must be monitored closely for hepatic toxicity while the dose is being escalated and periodically while on a maintenance dose
- take folic acid daily to prevent side effects such as oral ulcers
- avoid alcohol b/c of risk of hepatotoxicity
- counsel female patients on proper birth control methods b/c of risk of teratogenicity, the capability of producing fetal malformation
- patients with renal insufficiency require lower doses of methotrexate
Antirheumatic: Methotrexate (rheumatrex)
Mechanism of action:
- unknown
- thought to affect immune funciton
