Rheumatoid arthritis Flashcards
Define RA
Autoimmune disease of synovial lining of joints, tendon sheaths and bursa.
Type of inflammatory arthritis
symmetrical polyarthritis – (affects multiple joints symmetrically)
Risk factors of RA
- 40 – 60 yrs
- Females
- Smoker, alcohol, obesity, low exercise
- FHx and genetics:
o HLA DR4 (a gene often present in RF positive patients)
o HLA DR1 (a gene occasionally present in RA patients) - Occupation – some chemiacls in air can trigger RA – e.g silica and chemical fertilisers.
- Infections – trigger.
Describe the pathophysiology of RA
- Exposure to an ext trigger (e.g smoking, infection, occupation trigger etc) in a genetically predisposed person – leads to abn autoimmune response against synovial joints – chronic inflammation and joint damage.
- During this inflammatory response – body makes citrullinated proteins – immune sys reacts to this by making Cyclic citrullinated peptide antibodies (anti-CCP autoAb - ACPA).
- Smoking promotes the citrullination of self proteins
- The abn response against the citrullinated proteins may be delayed – this means that symp will present later. - Followed by targeting stage – involves activation of innate (macrophages, neutrophils) and adaptive (T and B cells) – they infiltrate synovial joint – pro-inflammatory response.
o This causes synovitis – presents sym polyarthropathy of small joint.
How does RA present?
- Onset can be rapid (overnight) or gradual (months-yrs).
- Symmetrical distal polyarthropathy
Signs:
- Swollen, painful, red, tender joints.
- “BOGGY” feeling on palpation of synovium around joints.
- Stiffness – worse in morning, lasting > 30mins
- RA is a type of inflammatory arthritis – therefore pain increases with rest and improves w/ activity.
- Reduced range of motion
- Difficult with fine motor tasks – e.g buttoning shirt
- Muscle atrophy
symp:
- Systematic symp:
o Fatigue
o Flu like illness
o Muscle aches and weakness
o Fever
o Weight loss
What joints are commonly affcted in RA?
o PIP – proximal interphalangeal joints
o MCP – metacarpophalangeal joint
o Wrist and ankle
o Metatarsophalangeal joints
o Cervical spine
o Larger joints – knee, hip and shoulders.
DIP JOINTS NOT AFFECTED BY RA – SWOLLEN, PAINFUL DIP = HEBERDEN’S NODES = OA
RA also SPARES LUMBAR AND THRACIC SPINE.
Define Palindromic rheumatism
self limiting short ep of inflammatory arthritis w/ joint pain, stiffness and swelling.
- Affects few joints.
- Ep last 1-2 days and resolve – having RF and anti-CCP – indicate progression to full RA.
Long-term effects of RA on the hands.
- Boutonniere deformity
- Swan neck deformity
- Ulnar deviation at MCP
- Z deformity at wrist
- Wrist +/- MCP subluxation
Long-term effects of RA on the feet
- Hammer toes
- Hallux valgus (bunion)
- MTP subluxation – (subluxation is a partial dislocation – causes crossing over)
Long-term effects of RA on eye
- Keratoconjunctivitis sicca – dry eyes
- Episcleritis – inflammation fo superficial layer of sclera
- Scleritis – inflammation of whole sclera.
Long-term effects of RA on mouth and oral cavity.
- Xerostoma (dry mouth)
- Oral ulcers
long-term effects of RA on the lungs/ respiratory system.
- Interstitial lung disease
- Serositis – inflammation of serous mem (pleura, pericardium and peritoneal) – can lead to pul fibrosis
- Bronchiolitis obliterans (inflammation causing small airway destruction)
- Costochondritis
- Pleural effusion containing RA
- Rheumatoid nodes seen on XRAY – can be asymp
long-term effects of RA on the/ CVS
- Pericarditis
- Myocarditis
- Non infective endocarditis
- Increased risk of IHD – due to vasculitis
- Pericardial effusion containing RA
long-term effects of RA on the kidney
- Glomerulonephritis – due to vasculitis
- Amyloidosis in kisney – causing nephrotic syn
long-term effects of RA on the nervous system
- Peripheral neuropathy
- Carpal tunnel syn
- Cervical myelopathy (damage to tissue of spinal cord)– due to atlantoaxial subluxation
long-term effects of RA on the haematological system.
- Neutropenia
- Thrombocytopenia or thrombocytosis
- Anemia of chronic disease
- Haem malignancy
- Splenomegaly
- Amyloidosis
long-term effects of RA on the skin
- Rheumatoid nodules – dark, hard nodules, common on elbow
- Vasculitis skin rash – ulcer, digital gangrene, splinter haemorrhages
- Pyoderma gangrenosum
- Raynaud’s syn – blood vessels go into temp spasm – limits BF – white to blue to red (triggered by cold, anxiety)
What is Atlantoaxial subluxation ? How does it present?
increased mobility between the body of the C1 vertebra (atlas) and the odontoid process of the C2 – due to damage to stabilizing ligaments.
- Presents as neck pain – radiates to occiput
- Can result in myelopathy – weakness and altered sensation in upper limb.
- Minor neck trauma in RA Ptx can worsen this – odontoid peg can migrate upwards through foramen magnum – cause spinal cored compression, compress vertebral A – sudden death.
- RA ptx at risk – C spine imaging.
How is RA diagnosed?
clinical manifestations and following tests.
- Bloods - Raised inflammatory markers and anemia of chronic disease.
o Inflammatory makers used to monitor progression. - Serological makers of RA - If RF is neg, check anti-CCP Ab
o RF - specific for RA and can help support the diagnosis, though does not confirm it. RA patients that are RF positive tend to have more systemic involvement and a worse prognosis.
o Anti-CCP – A positive anti-CCP is even more specific than RF for rheumatoid arthritis and can support the diagnosis, though does not confirm it. - US of joints to evaluate synovitis.
- XRAY
What XRAY changes are seen in RA?
- Soft tissue swelling
- Periarticular osteopenia – low bone density surrounding joint
- juxta-articular/ bony erosions
- narrowed joint space
- Joint destruction and deformity/ bone displacement
What is the ACR diagnostic criteria?
Patients are scored based on:
1. The joints that are involved (more and smaller joints score higher)
2. Serology (rheumatoid factor and anti-CCP)
3. Inflammatory markers (ESR and CRP)
4. Duration of symptoms (more or less than 6 weeks)
Scores are added up and a score greater than or equal to 6 indicates a diagnosis of rheumatoid arthritis.
What is the DAS28 scoring system? How is it used?
- Assess all 28 joints and points given for:
o Swollen joint
o Tender joint
o ESR/ CRP result - Score < 2.6 – remission, free from symp
- 2.6 – 3.2 – low disease
- 3.2 – 5.1 - moderate disease
- > 5.1 – high disease – indication for DMARDs
How is RA managed?
- Symp relief
- NSAID/ COX-2 inhibitors for pain, stiffness and swelling.
o High risk GI upset – so give PPI
- During flares – intra-articular or oral steroids.
- Physio to maintain muscle strength around joint
- Occupational therapy – physical aids to limit stress put on joint
- Surgery - arthroplasty, fusion or synovectomy - DMARDs
- Biological therapies
yearly influenza and pneumococcal vaccine every 5 yrs.
Write out the DMARD Tx regime.
- 1 st line – monotherapy w/ methotrexate, leflunomide OR sulfasalazine
o Hydroxychloroquine if mild disease - 2nd line – combination of 2 above
- 3rd line – methotrexate + biological therapy
- 4th line – methotrexate + rituximab
How does pregnanacy affect RA symptoms?
Preg women – temp relief of symp due to increase in steroid hormone production in preg.
