Rheumatoid arthritis

Question 1

Define RA

Answer 1

Autoimmune disease of synovial lining of joints, tendon sheaths and bursa.
Type of inflammatory arthritis
symmetrical polyarthritis – (affects multiple joints symmetrically)

Question 2

Risk factors of RA

Answer 2

• 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.

Question 3

Describe the pathophysiology of RA

Answer 3

1. 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.
2. 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.
3. 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.

Question 4

How does RA present?

Answer 4

• 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

Question 5

What joints are commonly affcted in RA?

Answer 5

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.

Question 6

Define Palindromic rheumatism

Answer 6

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.

Question 7

Long-term effects of RA on the hands.

Answer 7

• Boutonniere deformity
• Swan neck deformity
• Ulnar deviation at MCP
• Z deformity at wrist
• Wrist +/- MCP subluxation

Question 8

Long-term effects of RA on the feet

Answer 8

• Hammer toes
• Hallux valgus (bunion)
• MTP subluxation – (subluxation is a partial dislocation – causes crossing over)

Question 9

Long-term effects of RA on eye

Answer 9

• Keratoconjunctivitis sicca – dry eyes
• Episcleritis – inflammation fo superficial layer of sclera
• Scleritis – inflammation of whole sclera.

Question 10

Long-term effects of RA on mouth and oral cavity.

Answer 10

• Xerostoma (dry mouth)
• Oral ulcers

Question 11

long-term effects of RA on the lungs/ respiratory system.

Answer 11

• 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

Question 12

long-term effects of RA on the/ CVS

Answer 12

• Pericarditis
• Myocarditis
• Non infective endocarditis
• Increased risk of IHD – due to vasculitis
• Pericardial effusion containing RA

Question 13

long-term effects of RA on the kidney

Answer 13

• Glomerulonephritis – due to vasculitis
• Amyloidosis in kisney – causing nephrotic syn

Question 14

long-term effects of RA on the nervous system

Answer 14

• Peripheral neuropathy
• Carpal tunnel syn
• Cervical myelopathy (damage to tissue of spinal cord)– due to atlantoaxial subluxation

Question 15

long-term effects of RA on the haematological system.

Answer 15

• Neutropenia
• Thrombocytopenia or thrombocytosis
• Anemia of chronic disease
• Haem malignancy
• Splenomegaly
• Amyloidosis

Question 16

long-term effects of RA on the skin

Answer 16

• 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)

Question 17

What is Atlantoaxial subluxation ? How does it present?

Answer 17

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.

Question 18

How is RA diagnosed?

Answer 18

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

Question 19

What XRAY changes are seen in RA?

Answer 19

• Soft tissue swelling
• Periarticular osteopenia – low bone density surrounding joint
• juxta-articular/ bony erosions
• narrowed joint space
• Joint destruction and deformity/ bone displacement

Question 20

What is the ACR diagnostic criteria?

Answer 20

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.

Question 21

What is the DAS28 scoring system? How is it used?

Answer 21

• 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

Question 22

How is RA managed?

Answer 22

1. 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
2. DMARDs
3. Biological therapies

yearly influenza and pneumococcal vaccine every 5 yrs.

Question 23

Write out the DMARD Tx regime.

Answer 23

• 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

Question 24

How does pregnanacy affect RA symptoms?

Answer 24

Preg women – temp relief of symp due to increase in steroid hormone production in preg.