Rheumatoid Arthritis Flashcards
What is rheumatoid arthritis?
A chronic systemic inflammatory disease characterised by a symmetrical, deforming, peripheral polyarthritis.
Epidemiology of RA.
1%
Higher in smokers
Female > Male 3:1
Peak onset in 5th to 6th decade (workbook says 30-50 yo)
HLA DR4/DR1 linked.
Pathophysiology of RA.
Citrullination of self antigens which are then recognised by T and B cells which can then produce antibodies RF and anti-CCP.
Stimulated macrophages and fibroblasts produce TNFalpha.
The inflammatory cascade leads to proliferation of synoviocytes leading to a boggy joint sweling typical of RA. The synoviocytes grow over the cartilage and lead to restriction of nutrients, this leaves the cartilage damaged.
Activated macrophages stimulate osteoclast differentiation contributing to bone damage.
Typical clinical presentation of RA.
Symmetrical swollen, painful and stiff small joints of hands and feet that is worse in the morning.
The arthritis is progressive, peripheral and symmetrical.
Must have a history of over 6 weeks for diagnosis.
Morning stiffness > 30 mins duration.
Commonly co-exist with fatigue and malaise.
What joints are commonly affected in RA?
MCPs, PIPs and MTPs.
DIPs are typically spared
Hips, knees, shoulders and cervical spine can also be affected but this is less common.
Less common presentation of RA.
Sudden onset with wide spread arthritis
Reccuring mono/polyarthritis of various joints also called palindromic RA.
Persistent monoarthritis of knees, shoulders or hips.
Systemic illnesss with extra-articular symptoms.
Polymyalgic onset.
Recurrent soft tissue problems.
Early signs of RA.
Swollen MCP, PIP, wrist or MTP joints that are often symmetrical.
Look for tenosynovitis or bursitis.
Late signs of RA.
Ulnar deviation and subluxation of the wrist and fingers.
Boutonnieres and Swan-neck deformities
Z-deformity of the thumbs
Hand extensor tendons can rupture
Foot changes are similar
Spinal cord deformity due to atalanto-axial joint subluxation.
Examination of RA.
Soft tissue swelling and tenderness
Ulnar deviation/palmar subluxation of MCPs
Swan-neck and Boutonniere deformity of fingers
Z-deformity of thumbs
Rheumatoid nodules most common at the elbows
Carpal tunnel syndrome.
Investigations of RA.
- RhF (70% of people +ve) and anti-CCP (more sensitive and specific)
- FBCs - normocytic anaemia (anaemia of chronic disease), raised platelets, raised ESR and CRP.
- X-rays
- Ultrasound (more sensitive in early disease)
- MRI (more sensitive in early disease)
- Possible PFTs and HRCTs if there is chest involvement.
X-ray features of RA.
Loss of joint space
Erosions (periarticular)
Soft tissue swelling
Subluxation
When are extra-articular manifestations of RA more common?
If the patient is RF+ and anti-CCP positive.
Since RF+ and Anti-CCP does not offer a definitive diagnosis.
What is it more suitable to use as?
A prognostic factor of the disease.
Extra-articular manifestations of RA.
Pulmonary fibrosis with pulmonary nodules (Caplan’s syndrome)
Bronchiolitis obliterans (inflammation causing small airway destruction)
Felty’s syndrome (RA, neutropenia and splenomegaly)
Secondary Sjogren’s Syndrome (AKA sicca syndrome)
Anaemia of chronic disease
Cardiovascular disease
Episcleritis and scleritis
Rheumatoid nodules
Lymphadenopathy
Carpel tunnel syndrome
Amyloidosis
Easy way to remember extra articular manifestations of RA.
3Cs
3As
3Ps
3Ss
What are the 3Cs of RA?
CTS
Cardiac risk
Cord compression
What are the 3As of RA?
Anaemia
Amyloidosis
Arteritis
What are the 3Ps of RA?
Pericarditis (uncommon)
Pleural disease (common)
Pulmonary disease (common) e.g. bronchiectasis, bronchiolitis obliterans, fibrosis.
What are the 3Ss of RA?
Sjögrens (common)
Scleritis/episcleritis (uncommon)
Splenomegaly
Criteria for diagnosing RA.
Those with one ore more swollen joints and a suggsetive clinical history not better explained by other disease.
A score of ABCD is done.
6 ore more is diagnostic.
What are the score criteria to diagnose RA?
Joint involvement;
1 large joint = 0
2-10 large joints = 1
1-3 small joints = 2
4-10 small joints = 3
>10 joints (at least one small) = 5
Serology;
-ve for RF and anti-CCP = 0
Low +ve RF or low +ve anti-CCP = 2
High +ve RF or high +ve anti-CCP = 3
Acute phase reactants;
Normal CRP and ESR = 0
Abnormal CRP or ESR = 1
Duration of symptoms;
< 6 weeks = 0
> 6 weeks = 1
Treatment of RA.
Refer early to a rheumatologist.
Disease activity is measured using the DAS28 - Disease activity score to assess tenderness and swelling at 28 joints.
Early use of DMARDs as monotherapy usually methotrexate.
Consider combination of DMARDs like leflunomide, hydroxychloroquine and sulfasalazine.
Use steroids to rapidly reduce symptoms and inflammation. Generally used for acute exacerbations like IM methylprednisolone 80-120 mg.
NSAIDs are good for symptom relief but have no effect on disease progression. PPi should be given as well.
If disease is still severe after combination with DMARDs then consider biologics.
Surgery, physio and occupational therapy.
Podiatry and psychological therapy.
Quit smoking.
Treatment algorithm according to NICE
How is methotrexate taken?
By injection or tablet once a week.
Folic acid 5mg is also prescribed once a week to be taken on a different day.
ADRs of methotrexate
Mouth ulcers and mucositis
Liver toxicity
Pulmonary fibrosis
Bone marrow suppression and leukopenia (low white blood cells)
It is teratogenic and needs to be avoided prior to conception in mothers and fathers
How does leflunomide work?
Interfere with the production of pyrimidine that is important to make RNA and DNA.
ADRs of leflunomide
Mouth ulcers and mucositis
Increased blood pressure
Rashes
Peripheral neuropathy
Liver toxicity
Bone marrow suppression and leukopenia (low white blood cells)
Teratogenic
ADRs of Sulfasalazine
Temporary male infertility (reduced sperm count)
Bone marrow suppression
Hydroxychloroquine ADRs
Nightmares
Reduced visual acuity (macular toxicity)
Liver toxicity
Skin pigmentation
ADRs rituximab
Vulnerability to severe infections and sepsis
Night sweats
Thrombocytopenia
Peripheral neuropathy
Liver and lung toxicity
Methotrexate: pulmonary fibrosis
Leflunomide: Hypertension and peripheral neuropathy
Sulfasalazine: Male infertility (reduces sperm count)
Hydroxychloroquine: Nightmares and reduced visual acuity
Anti-TNF medications: Reactivation of TB or hepatitis B
Rituximab: Night sweats and thrombocytopenia
