RA - Rheumatoid Arthritis Flashcards
What is rheumatoid arthritis (RA)?
Autoimmune disorder causing symmetrical joint pain, swelling, and synovial destruction
What are the risk factors for RA?
(1) HLA DRB1
(2) smoking, infection
(3) Higher incidence in females (3:1 ratio)
At what age is RA most prevalent?
Prevalence peaks between 40-60 years
Describe the pathophysiology of RA
The synovium becomes inflamed, leading to the destruction of cartilage and bone by inflammatory mediators
What triggers are implicated in RA?
Smoking, infection, and trauma
What forms as a result of synovial inflammation in RA?
An inflammatory pannus (granulation tissue) forms, which destroys the cartilage extracellular matrix
What autoantibodies are generated in RA?
(1) Anti-citrullinated peptide antibodies (anti-CCP)
(2) Rheumatoid factor (RF)
What is rheumatoid factor (RF)?
RF is an IgM or IgA antibody that binds to the Fc region of IgG
What are the main articular symptoms of RA?
(1) Symmetrical joint pain
(2) Swelling of affected joints
(3) Morning stiffness (>30 minutes)
(4) Affecting small joints like PIPs, MCPs, and MTPs
(5) Reduction in grip strength
Which joints are typically spared in RA?
The DIP joints
What spinal involvement can occur in RA?
Atlanto-axial subluxation (C1-C2)
= Only joint in spine with synovium
What blood tests are indicative of RA?
Inflammatory - (CRP, Plasma Viscosity, ESR)
Autoantibodies - Rheumatoid factor or anti CCP antibodies
What is the DAS28 score used for?
Measure disease activity in RA by
(1) counting tender/swollen joints
(2) CRP levels
(3) Patient’s assessment of the disease
What is the first-line treatment for RA?
DMARD monotherapy → methotrexate.
Within 3 months of symptom onset. Often with a corticosteroid bridge
What is the second-line treatment if the first DMARD fails?
Combination DMARD therapy, such as methotrexate with hydroxychloroquine or sulfasalazine
What is the third-line treatment for RA?
Biologics or targeted synthetic DMARDs, such as TNF-inhibitors
Name a key side effect of methotrexate
(1) Bone marrow suppression
(2) Infection
(3) Liver function derangement
(4) Pneumontitis
(5) Nausea
What is Felty’s syndrome?
Triad of
1. RA
2. Neutropenia
3. Splenomegaly
How is hydroxychloroquine monitored for safety?
Requires retinal screening 5 years after starting, as it can cause retinal toxicity
Negative antibodies exclude RA. True or False
false
X-rays are abnormal in early RA, and normal X-rays exclude RA. True or false
False
Ideally, when should DMARD therapy be started in Rheumatoid Arthritis?
As soon as diagnosis of RA confirmed ( ideally within 3 months of symptom onset)
In a patient with newly diagnosed rheumatoid arthritis, what is the best treatment choice?
Methotrexate
Is Methotrexate safe in pregnancy?
Nope
In a patient with newly diagnosed rheumatoid arthritis, what is the best treatment choice?
Methotrexate
A 42-year-old man started on Methotrexate 12 weeks earlier for rheumatoid arthritis.
He is now complaining of a cough and some breathlessness when walking up stairs.
He has crackles at both lung bases.
What would you be most concerned about?
He has methotrexate pneumonitis
A 36-year-old man has rheumatoid arthritis and has very sore joints despite treatment with methotrexate, sulphasalazine and hydroxychloroquine. His DAS 28 score is 5.88
What would be the next stage in treatment? and why?
Start anti-TNF therapy
= As he has tried 2 different DMARDs, and disease activity remains high ( ie. DAS28 > 5.1) he qualifies for a biologic therapy.
He is started on certolizumab and does very well. He then returns to the clinic feeling tired and having lost 2 stone in weight. He has a cough.
It transpires that he spent 2 years as a teenager in Subsaharan Africa
What condition are you concerned about?
Tuberculosis
Which chest X-ray finding are you most likely to find in a patient recently diagnosed with sarcoidosis?
Bilateral hilar lymphadenopathy
On initial diagnosis of rheumatoid arthritis, how many and which DMARDs should be prescribed?
A combination of 2 DMARDs should be used upon diagnosis. One of them is usually methotrexate
What medications are safe to control symptoms of Rheumatoid Arthritis during pregnancy?
(1) Mild → Simple analgesia with Paracetamol with a weak opioid can be sufficient
(2) Flare-ups → Low dose Prednisolone can be added
(3) Hydroxychloroquine and/or Sulfasalazine with concomitant Folic Acid can be continued during pregnancy
When should patients with small joint swelling and suspected persistent synovitis in primary care be referred to a Rheumatology service?
Within three working days
How long is the washout period for Methotrexate in women with Rheumatoid Arthritis who are planning on starting a family?
3 months
What DAS scores indicate high disease activity levels?
above 5.1
What are the baseline blood tests required when Hydroxychloroquine is initiated for Rheumatoid Arthritis?
Full blood count, urea and electrolytes, creatinine and liver function tests
What is the treatment for a new presentation of rheumatoid arthritis?
Steriods + DMARDS
DMARDs are methotrexate and hydroxychloroquine
Which treatments for rheumatoid arthritis slow down progression of the disease?
(1) DMARDs eg. Methotrexate, Sulfasalazine, Hydroxychloroquine, Leflunomide
(2) Biologics eg. Anti-TNF’s such as infliximab
What group of patients with Rheumatoid Arthritis is Felty’s Syndrome more common in?
extra-articular manifestations
What is the specificity and sensitivity of Rheumatoid Factor?
Around 70%
Why can Folic Acid not be taken on the same day as Methotrexate?
Folic Acid (5mg) has to be prescribed together with Methotrexate and has to be taken on a separate day to avoid interference with the therapeutic action of Methotrexate
What are the main risk factors for rheumatoid arthritis?
Female sex (three times as common)
Smoking
What change in DAS score indicates no response to treatment?
A change in DAS score of 0.6 or less
Which drugs can interact with methotrexate to potentiate its toxic effects?
Drugs that also inhibit the metabolism of folate
> Trimethoprim
Which autoantibody is considered specific for polyarteritis nodosa?
pANCA
How does Etanercept work?
Etanercept is a TNF receptor
What change in DAS score indicates a good response to treatment?
DAS score of more than 1.2
What is the classic pattern of joint involvement in rheumatoid arthritis?
(1) Symmetrical
(2) Polyarticular arthritis involves the small joints of
(3) The distal interphalangeal joints are usually spared
What change in DAS score indicates a moderate response to treatment?
A change in the DAS score of between 0.7 to 1.2
What DAS scores indicate remission?
DAS scores below 2.6
A 53-year-old woman is seen in the rheumatology clinic. She has a long-standing diagnosis of rheumatoid arthritis, which has been refractory to several disease-modifying agents.
What is most likely to be seen on examination?
Ulnar deviation
Das Score: < 2.6 indicates what?
disease remission
Das Score: 2.6-3.2 indicates what?
low disease activity
Das Score: 3.2-5.1 indicates what?
moderate disease activity
Das Score: 5.1 indicates what?
high disease activity
Factors associated with a poor prognosis include what?
(1) Positive rheumatoid factor and anti-CCP antibodies
(2) Insidious disease onset
(3) Smoking history
(4) HLA-DR4 and poor functional status at presentation
Lack of anti-CCP antibodies is what type of prognosis?
Good
A 36-year-old woman is seen in the rheumatology clinic. She has recently been started on medication for her severe rheumatoid arthritis. Her doctor explained that this medication works by inhibiting calcineurin and thereby reducing the activity of T lymphocytes.
Unfortunately, she has developed severe diarrhoea since starting this new medication and would like to switch to a different one.
What is the medication that she has been started on? and why?
Ciclosporin
= lowers the activity of T lymphocytes by inhibiting calcineurin, which is normally responsible for activating the transcription of interleukin 2. It is used as an immunosuppressant in autoimmune conditions and following organ transplants, to prevent rejection. Diarrhoea is a common side effect
A 35-year-old female with rheumatoid arthritis attends the rheumatology clinic for a review. Since her diagnosis 2 years ago she has been treated with two different combinations of DMARDs and is now on methotrexate and sulfasalazine.
Despite this, her disease is still severe and she constantly suffers a high degree of pain, swelling and stiffness in most of the joints in her hands and feet which has stopped her from working. Her DAS28 score is 5.5.
Given the likely medication she is going to be started on, what is an important screening investigation that must be done beforehand? and why?
Chest XRAY
= To rule out TB infection or lung pathology before you initiate a TNF alpha inhibitor - Infliximab
Infliximab can increase the risk of TB reactivation, especially in those with previous exposure
Fatigue, mouth sores, and shortness of breath is seen in patients who…
has methotrexate toxicity
According to NICE guidelines, patients reviewed in primary care who have the following features must be urgently referred to a Rheumatology service. These features include what?
(1) Small joints of the hands or feet are affected
(2) More than one joint is affected.
(3) There has been a delay of 3 months or longer between the onset of symptoms
(4) The person is seeking medical advice
What age is common for those suffering from felty syndrome?
50-70
X-ray changes seen in rheumatoid arthritis include what?
(1) Periarticular osteopenia- this is often an early sign
(2) Joint erosions
(3) Periarticular soft tissue swelling
(4) Joint space narrowing
A 65-year-old female with long-standing rheumatoid arthritis arrives on the cardiology ward in advance of an elective aortic valve replacement. You complete your usual pre-operative assessment, but when you mention to the anaesthetist that the patient has longstanding rheumatoid arthritis, they request an additional investigation.
Which additional investigation would be most appropriate when considering the anaesthetic approach to a patient with RA?
C-spine x-ray
