بسم الله الرحمن الرحيم Rheumatoid Arthritis
(RA)
RA
Is a chronic systemic inflammatory disease of unknown etiology & is considered the commonest inflammatory arthritis. Characterized by: 1. Symmetrical inflammatory polyarthritis. 2. It has extra articular features 3.Progressive joint damage causing severe disability.
RA is a worldwide disease affects all racial & ethnic groupsAffects 1-3% of population Female: male is 3:1 Females have more articular disease and males have more systemic presentations.Age range is 10 – 70y. ( starts 30- 40y) 5-10% having family history & 70% have HLADR4. Epidemiology
Genetics
1st-degree relatives have 1.5 fold higher risk than the general populationTwins show heritability of 60%HLA-DR4 person has increased relative risk 4–5 times.Etiology & Pathogenesis
The cause is unknown & said to be an autoimmune diseaseMultifactorial ( i.e. Genetic, environment…)Cytokines , growth factors , tumor necrosis factors & metalloproteases have a role .Commonly affected joints are MCPs, PIPs, wrists, MTPs & larger joints. Might starts with few joints then progress& become symmetric. Monoarticular is not uncommon ( episodic) Thoracolumbar , sacroiliac & DIP joints are very rarely involved. It has systemic manifestations, extra aricular features.
Clinical Features
Progression of the disease will lead joint destruction resulting in: limitation of joint motion instability sublaxation & deformities Non articular symptoms e.g. carpal tunnel syndrome.
Signs Swelling, Warmth,Limitation of movements, Deformities, Nodules
Hand deformities Radial deviation at wrist Ulnar deviation at MCP joints Swan neck deformity ( hyperextension at PIPs) Boutonniere deformity( flexion at PIPS) or called Z deformity. Feet deformities are like those occur in hands
The knees Synovial effusion Deformities( valgus, varus &/ or flexion ) Bakers cyst in popliteal fossa which may repture. ( sudden onset of pain & swelling in calf and ankle) diagnosed by US. & arthrogram.
SYSTEMIC MANIFESTATIONS
DiagnosisDiagnostic Tests & InterpretationInitial lab testsHematocrit: Mild anemia, leucopenia (may be leucocytosis) & thrombocytosis. ESR: Usually elevatedC-reactive protein: UnspecificRheumatoid factor (RF): >1:80 in 70–80% of patients with RA (most commonly IgM Ab):Doesn’t correlate with disease activity but with extra articular manifistationsAnticyclic citrullinated peptide antibodies (Anti-CCP antibodies) are highly specific and present early( Linked to erosive RA). Anti-MCV assay (antibodies against mutated citrullinated Vimentin). Recently a serological point-of-care test (POCT) for the early detection of RA has been developed. This assay combines the detection of rheumatoid factor and anti-MCV for diagnosis of RA and shows a sensitivity of 72% and specificity of 99.7%.Antinuclear antibody: Present in 20–30%Electrolytes, creatinine, liver function, urinalysis to assess comorbid states.
Follow-Up & Special Considerations RF is not useful for monitoring course of illness. Radiographs of the hands, wrists, and feet can be repeated to follow disease progression.
Imaging Radiographic abnormalities are very useful in the diagnosis and treatment. Periarticular osteopenia is the earliest change. Juxta-articular bone erosions Symmetrical joint space narrowing. CT/MRI and ultrasound are useful in cervical-spine symptoms or detection of early joint erosions. Bone scan if suspected aseptic necrosis
Diagnostic ProceduresSynovial fluid:No pathognomonic findingsYellowish-white, turbid, poor viscosityWBC increased (3,500–50,000)Protein: ∼4.2 g/dL (42 g/L)
Goals: Relieving pain Controlling disease activity Improving function Preventing or correcting impairments
Treatment
First Line Medication Nonbiologic DMARDs: DMARDs within 2 months of diagnosis if patient has ongoing active disease despite appropriate dose of aspirin or other NSAIDs. Offer proton pump inhibitors (PPIs) for chronic NSAID therapy Nonbiologic DMARD: Methotrexate, sulfasalazine, or leflunomide low-dose corticosteroids + NSAIDs to maximize symptoms management.Biological DMARDs: Tumor necrosis factor (TNF) inhibitors: infliximab , adalimumab and etanercept. Check TB prior to treatment and periodic CBC, Risk of lymphoma, CHF. Anakinra : an IL-1 receptor antagonist Abatacept and rituximab : for active moderate to severe RA with inadequate response to other DMARDs or failed anti-TNF agent. Two long-acting anti-TNF agents, Certolizumab and golimumab,
Older Nonbiologic DMARDs Have been abandoned in developed countries for the treatment of RA: Injectable gold, D-Penicillamine, Cyclosporine, & Azathioprine.
Second Line Intra-articular steroids: If disease is well controlled except for a single joint or two, after establishing that the joint is not infected Hyaluronate: Hyaluronic acid , for pain relief; exact role in RA is unclear.