Rheumatology

Definition

chronic systemic inflammatory disorder affected synovium bone, cartilage, ligaments with extra-articular manifestations


RA is a chronic disease that leads to joint damage within the first 2 years, causes marked functional limitation and a 30% loss of work within the first 5 years, and shortens life by 5 to 7 years.

Epidemiology

RA occurs throughout the world and in all ethnic groups. The prevalence is lowest in black Africans and Chinese, and highest in the Pima Indians of Arizona. In Caucasians it is around 1.0-1.5% with a female:male ratio of 3:1. Before the age of 45, the female:male ratio is 6:1. Prevalence increases with age, with 5% of women and 2% of men over 55 years being affected.

Etiology

Genetic factors. Family studies have demonstrated an increased risk for disease in siblings of persons affected with RA. Concordance in monozygotic has been found to be 12% to 15% and 4% in dizygotic twins.

Enviromental

viruses (e.g., parvovirus B19, Epstein-Barr virus), Mycoplasma, and other bacteria (e.g., streptococci). Urbanization has a major impact on incidence & severity of R.A. cigarete smoking

Cellular immunity

Tissue Phase


Histopathology
The synovium of RA assumes the appearance of a reactive lymph node because of the extensive infiltration by plasma cells, macrophages, and lymphocytes in the form of large lymphoid follicles.

One characteristic feature of RA is the invasion of and damage to cartilage, bone, and tendons by an infiltrating inflammatory synovial tissue mass called the pannus

Clinical Characteristics of Rheumatoid Arthritis

Diagnosis of RA is made with four or more of the following
Morning stiffness (> 1 hour Arthritis of three or more joint areas Arthritis of hand joints Symmetrical arthritis Rheumatoid nodules Rheumatoid factor seropositive (rheumatoid factor positive ) Radiological changes Duration of 6 weeks or more


Articular Morning stiffness, "gelling"Symmetrical joint swellingPredilection for wrists, proximal interphalangeal, metacarpophalangeal, and metatarsophalangeal jointsErosions of bone and cartilageJoint subluxation and ulnar deviationInflammatory joint fluidCarpal tunnel syndromeBaker's cyst


Joints Affected : Typically involves elbows, wrists, MCP, and PIP joints 1st & 2nd cervical vertebrae frequently involved Unaffected joints : Thoracolumbar spine, DIPs & SI joints

Rheumatoid Arthritis: PIP Swelling

Swelling is confined to the area of the joint capsule Synovial thickening feels like a firm sponge
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Rheumatoid HAND
An across-the-room diagnosis Prominent ulnar deviation in the right hand MCP and PIP swelling in both hands MCP sublaxation Synovitis of left wrist
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hyperextension of the DIP joint of the finger (boutonniere deformity, occurs as a consequence of synovitis with stretching of, or rupture of, the PIP joint through the central extensor tendon with concomitant volar displacement of the lateral bands.

Hyperextension at the PIP joint with flexion of the DIP joint (swan-neck deformity, may be initiated by disruption of the extensor tendon at the DIP joint with secondary shortening of the central extensor tendon .

Rheumatoid arthritis: carpal tunnel syndrome, hand

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Rheumatoid arthritis: subluxation and muscle artrophy, hands

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Rheumatoid arthritis: ruptured right popliteal cyst

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EXTRA-ARTICULAR MANIFESTATIONS OF RHEUMATOID DISEASE

Haematological
Anaemia Thrombocytosis Eosinophilia

Lymphatic

Splenomegaly Felty's syndrome Nodules Sinuses Fistulae

Ocular

Eapiscleritis Scleritis Scleromalaciaa Keratoconjunctivitis sicca

Vasculitis

Digital arteritis Ulcers Pyoderma gangrenosum Mononeuritis multiplex Visceral arteritis

Cardiac

Pericarditis Myocarditis Endocarditis Conduction defects Coronary vasculitis Granulomatous aortitis

Pulmonary

Nodules Pleural effusions Fibrosing alveolitis Bronchiolitis Caplan's syndrome

Neurological

Cervical cord compression Compression neuropathies Peripheral neuropathy Mononeuritis multiplex

Cutaneous features

Subcutaneous rheumatoid nodules occur almost exclusively in seropositive patients, usually at sites of pressure or friction such as the extensor surfaces of the forearm, sacrum, Achilles tendon and toes

Cardiovascular features

Asymptomatic pericarditis occurs in approximately 30% of patients with seropositive RA, with pericardial effusions and constrictive pericarditis being rare complications. Occasionally, granulomatous lesions result in heart block, cardiomyopathy, coronary artery occlusion or aortic regurgitation..

Rheumatoid arthritis: subcutaneous nodule, olecranon

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Rheumatoid arthritis: episcleritis

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Rheumatoid arthritis: scleromalacia

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Rheumatoid arthritis: scleromalacia perforans
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Rheumatoid arthritis: scleromalacia perforans, herniation of the dark pigmented uveal tissue
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Rheumatoid arthritis: vasculitis with small infarcts, fingers

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Rheumatoid arthritis: vasculitis and gangrene, fingers

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Rheumatoid arthritis: pulmonary nodules

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Laboratory Tests

Raised inflammatory markers . Reasonable correlation with clinical activityMild anemia & thrombocytosisS. Rheumatoid factor (Agglutination method). Positive in near 70-80% cases (western countries). Not specificAnti-CCP (citrulline – containing proteins) antibodies. Similar sensitivity to RF but more specific (up to 95%) *

Examination of joint fluid

the most helpful laboratory procedure. The fluid is inflammatory, with more than 10,000 white blood cells and a predominance of polymorphonuclear leukocytes, typically 80% or more. Rheumatoid factor, an IgM antibody directed to IgG, is found in 80 to 90% of patients with RA...


. XR-Findings
Peri articular osteopenia Marginal erosions (at least months of persistent activity) Joint space narrowing (cartilage loss) Ankylosis (wrists) Deformities
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A. Soft-tissue swelling, no erosions B. Thinning of the cortex on the radial side and minimal joint space narrowing C. Marginal erosion at the radial side of the metacarpal head with joint space narrowing
Joint damage progression in R.A. hand
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Prognosis

The following factors at presentation are associated with a poor prognosis: higher baseline disability female gender involvement of MTP joints positive rheumatoid factor disease duration of over 3 months.
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