Rheumatoid Arthritis(RA)
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Transcript of Rheumatoid Arthritis(RA)
Rheumatoid Arthritis(RA)
Dr. Gehan Mohamed
Learning objectives: At the end of this lecture the student should be able
to : understand definition,genetic predisposition of RA. Discuss pathophysiology, clinical features of RA. Identify Diagnostic Criteria ,Laboratory Features and
bad prognostic Features of Rheumatoid Arthritis.
RA Systemic inflammatory autoimmune
disorder Age incidence : 40-70 years of age
Genetics
Patients which have HLA-DRB have Increased risk for : RA development. Increased joint damage Increased joint need for surgery
Pathophysiology
Role of Immunolog in RA Macrophages:
Produce cytokines Cytokines (TNF-α) cause
systemic features Release chemokines recruit
PMNs into synovial fluid/membrane
TNF-α & IL-1: Proliferation of T cells Activation of B cells Initiates proinflammatory/joint-
damaging processes
TH-1 cells: Mediate disease processes Activate B cells
B cells: Release cytokines Plasma cells that produce
Ab
Osteoclasts induce: Bone erosion Juxta-articular & Systemic
osteoporosis
Pathophysiology Swelling of Synovial lining
Angiogenesis
Pannus formation in form of : Synovial thickening/hyperplasia Inflammatory vascularized tissue Generation of Metalloproteinases
Cytokine release Infiltration of leukocytes Change in cell-surface adhesion molecules & cytokines Destruction of bone & cartilage
Sequence of events : Proliferation of synovial membrane
cells with inflammatory cell infiltrate Destruction of joints Disability
Diagnosis:1- clinical criteria2- investigations
1- Diagnostic Criteria Symmetric peripheral polyarthritis Morning Stiffness >1 hour Extraarticular manifestations Rheumatoid nodules
Symmetric Peripheral Polyarthritis 3 or more Joints for >6 weeks Intermittent or Migratory involvement
Small Joints Hands & Feet Peripheral to Proximal
Leads to Deformity & Destruction of Joints Erosion of cartilage and bone
Stiffness Morning or after Prolonged Inactivity Bilateral > 1 hours
Reflects severe joint inflammation Better with movement Pain with pressure to joint Pain with movement of joint Swelling due to hypertrophy of synovium Effusion Hottness Redness
Physical Exam Decreased grip strength Carpal tunnel syndrome(condition
characterized by pain and numbing or tingling sensations in the hand and caused by compression of a nerve in the carpal tunnel at the wrist.
Ulnar deviation Boutonniere/Swan neck deformities Extensor tendon rupture
Extraarticular Involvement Myalgia, fatigue,
low-grade fever, weight loss, depression.
Anemia Rheumatoid nodules Pleuropericarditis Neuropathy
Scleritis Splenomegaly Vasculitis
Rheumatoid Nodules Extensor surfaces
elbows Very Specific Only occur in ~30% Late in Disease
Investigations
Arthrocentesis Confirm diagnoses Differentiate between inflammatory & noninflammatory Labs:
White blood cell count if WBC >2000/µL indicates inflammatory arthritis
Gram stain & Culture
Arthroscopy Evaluate ligamentous & cartilaginous integrity Biopsy Infection: aspirate thick
Rheumatoid arthritis : showing inflammatory cell infiltrate in the synovium
Laboratory Features Rhumatoid Factor
70-80% of pts. - Lab manifestations up to 10 years before clinical - IgM or IgG - If IgM+ve : more severe disease & poorer
outcome. Overlap with Hepatitis C Virus.
Acute Phase reactants ESR, CRP monitoring disease activity
Radiology Evaluate disease activity & joint
damage Bony decalcification
Radiological Studies Plain Films
Bilateral hands & feet
Color Doppler U/S & MRI Early signs of damage i.e. Erosions Bone Edema - even with normal findings on
radiography
DiseaseSeverity
Arthralgias >3 inflamed joints Mild functional limitation Minimally elevated ESR & CRP No erosions/cartilage loss No extraarticular disease
Mild Disease
Moderate Disease 6-20 Inflamed joints Moderate functional limitation Elevated ESR/CRP Radiographic evidence of
inflammation No extraarticular disease
Severe Disease >20 persistently inflamed joints Rapid decline in functional capacity Radiographic evidence of rapid
progession of bony erosions & loss of cartilage
Extraarticular disease
bad prognostic Features RF +ve Early development of multiple inflamed joints
and joint erosions Severe functional limitation Female HLA epitope presence Lower socioeconomic status & Less education Persistent joint inflammation for >12 weeks
Differential diagnosis of arthritis
Seronegative polyarthritis Psoriatic arthritis Osteoarthritis SLE Paraneoplastic syndrome Crystal-induced arthritis
Tophaceous gout Pseudogout