RA

Question 1

Mrs Rendina, 30 year old woman, presents to GP with pain and stiffness in feet and hands for 6/52; has made an appointment to see you because she is finding it very hard to use her hands in the morning

Questions on further Hx?

Answer 1

Joints affected

Characterising pain and stiffness: when does it occur, does the pain wake her from sleep, how long does pain and stffness last, etc

Aggravating and relieving factors including use of conventional pain relief

Associated features: constitutional symptoms, rash, nodules, etc

Other PHx, FHx, tobacco, alcohol, Rx, SHx

Question 2

Distinguish between the clinical features of mechanical and inflammatory joint pain

Answer 2

Question 3

Mrs Rendina, a 30 year old woman, presents to GP with 6/52 Hx of pain and stiffness in hands and feet with functional limitation

Pain and stiffness in PIP and MCP joints in hands and MTP joints in feet; hand pain wakes her at 4am and joint stiffness lasts until ~10am each day, paracetamol does not really help

Does not remember a rash or fever but 5 year old son was sent home from school 4/52 ago with “slapped cheek” syndrome

PHx: previously well

FHx: mother has RA

Tobacco and alcohol: smokes 5-10 cigarettes per day, no alcohol

Rx: combined OCP once daily

SHx: married, two children 5 and 7 years of age both at local school, works 4/7 a week as shop assistant, husband works fulltime with local council, mother and father live locally

DDx?

What features on physical examination would assist you in further refining your Dx hypotheses?

Answer 3

DDx: RA, SLE, psoriatic arthritis, parvovirus-associated arthritis

Vitals: look for elevated temperature

Joint examination: warmth, tenderness, visible and palpable soft tissue swelling, impaired or slow ROM, any deformities

CV examination

Resp examination: respiratory manifestions of arthropathy (e.g. fibrosing alveolitis, obliterative bronchiolitis)

Abdominal examination

Skin examination: dermatological manifestations of arthropathy (e.g. rheumatoid nodules)

Question 4

How do teenagers and adults tend to present with parvovirus?

Answer 4

Self-limiting arthritis

Question 5

Mrs Rendina’s physical examination reveals:

BP 110/75, HR 60 regular, RR 12, temp 36.7

Hands: look generally puffy with swollen PIP and MCP joints, all tender, ROM is normal but slow

Wrists: warm, not swollen

Elbows, shoulder, hips, knee: normal

Feet: squeezing the forefoot (MTP joints) is tender

All other systems normal

Further Ix?

Answer 5

FBE

ESR

Rheumatoid factor

ACPA

ANA

Parvovirus Ab

Question 6

Results of Mrs Rendina’s Ix:

FBE: ESR 26mm/hr (increased)

Rheumatoid factor normal

ACPA elevated

ANA negative

Parvovirus B19 Ab: IgM negative, IgG positive

Describe the diagnostic utility of ACPA and rheumatoid factor

If a patient is ACPA+ but RhF- what does this suggest?

Answer 6

ACPA: high specificity, low sensitivity (good for ruling in; high positive likelihood ratio)

RhF: not very specific or very sensitive (much lower positive likelihood ratio)

ACPA+ and RhF+: very specific, very high positive likelihood ratio

ACPA+ and RhF-: very specific, high positive likelihood ratio

So it is still possible for a patient to have RA if they are ACPA+ even if they are RhF-

Question 7

Describe the typical research criteria used to define RA

Answer 7

ABCD:

Arthritis (joint involvement): synovitis, with involvement of multiple joints (usually small)

Bloods (serology): ACPA, RhF

CRP, ESR (acute-phase reactants)

Duration of symptoms: >6 weeks

Question 8

SLICC Classification Criteria for SLE

Answer 8

≥4 criteria (at least 1 clinical and 1 laboratory) OR biopsy-proven lupus nephritis with positive ANA or anti-DNA

Clinical: acute cutaneous lupus, chronic cutaneous lupus, oral or nasal ulcers, non-scarring alopecia, arthritis, serositis, renal manifestations, neurologic manifestations, haemolytic anaemia, leukopenia, thrombocytopaenia

Immunologic: ANA, anti-DNA, anti-Sm, antiphospholipid Ab, direct Coombs test (do not count in presence of haemolytic anaemia)

Question 9

What are the goals of RA treatment?

Answer 9

Reduction of joint inflammation

Prevention of joint damage

Prevention of long-term RA-associated complications

Avoid drug complications

Maintenance of QoL (decrease pain and stiffness, improve functional capacity)

Question 10

According to the RACGP guidelines, when should RA be suspected?

What Ix should be ordered and what findings may be seen?

Answer 10

On Hx: joint pain and swelling and/or fever, morning stiffness >30 mins, previous episodes, FHx of RA, systemic flu-like features and fatigue

O/E: ≥3 tender and swollen joint areas, symmetrical joint involvement in hands and/or feet, positive squeeze at MCP or MTP joints

Ix: raised ESR and/or CRP, positive RhF and/or anti-CCP

Absence of any of these key symptoms, signs or test results does not necessarily rule out RA

Question 11

List 5 infections which can cause polyarthritis

Answer 11

Hepatitis B/C

Rubella

Parvovirus

Enteric infections

Question 12

What pharmacological interventions are indicated first-line in RA?

Answer 12

5As:

Analgesic: simple, i.e. paracetamol

Acids, fatty: omega-3 supplements

Anti-inflammatories (NSAIDs/COX-2 inhibitors)

Anti-rheumatic (DMARDs)

Adrenocorticosteroids: corticosteroids

Question 13

List 8 non-pharmacological interventions for initial RA therapy

Answer 13

Weight control

Patient education and self management programs

OT

Exercise (low-impact)

Psychosocial support

Sleep promotion

Appropriate foot care

Thermotherapy (heat or cold)

Question 14

When should DMARDs be considered for RA? When should rheumatology referral be considered

Answer 14

Several swollen joints, especially if tests for RhF and/or anti-CCP are positive

If persistent swelling beyond 6/52 (even if RhF and anti-CCP negative) and/or inadequate pain relief, consider referral

Question 15

Ongoing monitoring for RA patients

Answer 15

Joints effects: number, tenderness, swelling

Extra-articular: nodules, rash

CVD: BP and other RFs, renal function

Risk of infection

Toxicity: skin, lungs, GIT, heart, blood, urine

Lifestyle: smoking, weight loss, BMI

ADls: function, sleep, mood, fatigue

Annual foot review

Medication adherence

If long term corticosteroids: OP risk, BP, lipids, BSL, cataracts

Question 16

What is the treatment strategy for RA?

Answer 16

Pharmacological

Self-management

Allied health intervention (physio, OT, orthotists)

Surgery (no strong evidence base)

Question 17

Mechanism, complications and efficacy of NSAIDs in treatment of RA

Answer 17

Mechanism: decreased prostaglandin production by COX inhibition

Complications: peptic ulcers, mouth ulcers, enteropathy, rashes, hepatotoxicity, renal toxicity

Efficacy: good short and long term efficacy in inflammatory arthritis

Question 18

List 4 DMARDs commonly used for RA Mx

Answer 18

Hydroxychloroquine

Sulphasalazine

Methotrexate

Leflunomide

Question 19

List 4 biologic DMARDs used in RA Mx

Answer 19

TNF inhibitors (etanercept, adalimumab, infliximab, golimumab, certolizumab)

B cell inhibitor (rituximab)

Cell adhesion inhibitor (abatacept)

IL-6 inhibitor (tocilizumab)

Question 20

What are the different options for administration of steroids in RA?

Answer 20

Oral pred: efficacious but causes HTN, weight gain, skin changes, hyperglycaemia, OP

Intra-articular steroids: efficacious in accessible joints and few side effects if used intermittently

Question 21

Mrs Rendina is commenced on methotrexate and naproxen

What features on Mx interview and physical examination would you monitor to determine if Mrs Rendina has responded to therapy?

Answer 21

Disease activity measures:

Patient and physician global assessment (often using visual analogue scale)

Swollen and tender joint count (on examination)

Measures of inflammation (ESR or CRP)

Question 22

On review 8/52 after commencement of methotrexate and naproxen Mrs Rendina’s disease activity was:

Significant (50%) improvement in pain and stiffness

Swollen joint count reduced by 40%

ESR and CRP now normal

How is disease damage measured?

Answer 22

Bone and cartilage damage occurs more slowly than soft tissue swelling

MRI more sensitive than plain XRs for detecting synovitis, cartilage damage, bone oedema, bone erosions and periarticular osteopaenia

XRs usually not required in early Mx

Question 23

Anti-CCP, ACPA

Answer 23

Anti-cyclic citrullinated peptide

Anti-citrullinated protein Ab