- See: Stages of Rheumatoid Arthritis
- Discussion:
- affects 1-3% of adult population;
- female predominance of about 3 to 1;
- peak age of onset 35 and 45 years;
- most often presents with involvement in the feet and hands (intial involvement occurs in 15% and 14%, respectively);
- poor prognostic factors:
- high latex fixation titer;
- rheumatoid nodules;
- rapid rate of radiographic joint destruction;
- poor response to medications;
- diff dx:
- systemic lupus erythematosus;
- scleroderma;
- dermatomyositis;
- seronegative arthritis;
- psoriatic arthritis;
- Reiter's syndrome;
- AS;
- arthritis of chronic inflammatory bowel disease;
- rarely, polyarticular crystal deposition disease, polyarticular septic arthritis, & host of very unusual entities may be confused w/ RA;
- Clinical Manifestations:
- symmetrical polyarthralgias, morning stiffness, and fatigue are common;
- general fatigue and malaise may be present before joint symptoms;
- morning stiffness results from increases in extracellular fluid in & around joint;
- later on, there may be limitation of motion due to pain or joint destruction;
- although RA may involve any synovial joint, there is predilection for wrists and hands;
- MP joints, PIP joints, and wrists are first to become symptomatic;
- ulnar deviation, and swan-neck or boutonniere deformities are common;
- Extra Articular Manifestations:
- patients with extraarticular manifestations have increased mortality rate as well as more severe disability;
- extra-articular manifestations are more common w/ high-titer RF;
- heart (pericarditis, cardiomyopathy, and valvular incompetence caused by nodules, and interstitial fibrosis);
- eyes (scleritis, and occasionally scleromalacia perforans);
- rheumatoid scleritis is the most common ocular complication of RA, and generally indicates a poor prognosis;
- it is often associated w/ skin nodules, and a high titre of RF;
- incidence of iritis in RA is no greater than that found in general population;
- nodular scleritis is a more advanced stage of the previous case;
- nervous system (mononeuritis multiplex, and peripheral compression syndromes such as median neuropathy);
- vasculitic neuropathy occurs in 10% of these patients and in half of these patients (5%), neuropathies are predominantly sensory, whereas others (5%) present with a slowly progressive, distal symmetrical sensory or sensory-motor polyneuropathy;
- these neuropathies appear in severe and long-standing rheumatoid arthritis;
- kidneys (amyloid deposition);
- hematopoietic system (Felty's syndrome):
- anemia, splenomegaly, and leukopenia;
- vasculitis:
- usually is a non necrotising arteritis of the small terminal arterials, but occassionally taking the form of a fulminating arteritis;
- skin lesions, leg ulcers, necrotizing arteritis of the viscera, digital infarctions, and fever;
- Sjogren's syndrome:
- occurs in about 15% of RA pts;
- due to infiltration of exocrine glands w/ lymphocytes;
- keratoconjunctivitis, xerostomia, & lymphoid infiltration of parenchymal organs may occur;
- patients are at increased risk for developing lymphoid malignancies;
- Pathologic Changes in Specific Joints:
- cervical spine
- hand
- boutonniere
- extensor tendon rupture
- flexor tendon rupture
- MP joint
- thumb
- swan neck deformity
- PIP joint
- wrist
- radioulnar / radiocarpal joints
- caput ulna syndrome
- elbow
- hip
- foot