Test With Complete Solutions
Rheumatoid Arthritis
A chronic inflammatory polyarthritis of unknown etiology that targets the synovial tissue of movable
joints. Arthritis is the primary symptom but just one manifestation of a more extensive systemic
inflammatory process.
HLA-DR4 (a human leukocyte antigen)
A type of histocompatibility Class II antigen believed to be associated with an increased suspectibility
to RA and is is found in the majority of people with RA. Also an indicator of a more severe form of the
disease.
Synovial joint
Also called a diarthrodial joint is composed of two bones held together by fibrous capsule that is lined
with synovium. The two bones are capped with cartilage and are separated by a thin layer of synovial
fluid. Together they permit frictionless movement of the joint
Synovium
Provides nutrients to the avsacular cartilage. Produces hyalauonic acid that lubricates the joint.
Produces collagen and fibronectin used for the synovial matrix
Immunologic elements involved in the development of RA
T-Cells, macrophage/fibroblasts and B-Cells. Initially THelper 1 (TH1) CD4 cells are believed to be the
key to the inflammatory process.
Chronic Synovitis
A progressive process manifested by hypertroophy of the cells lining the synovium, neo-angiogenesis
(the growth of new blood vessels)....An influx of TNFs into the synovium activates the production of
other inflammtory cytokines and the fluid in the synovial cavity produces effusions (fluid in the joint
cavity). Pannus Formation, the end product of this process
Pannus Formation
The end product of the synovitis process.
Pannus
An aggressive inflammatory tissue that spreads across the joint surface infiltrating and eroding
adjacent bone and articular cartilage and producing enzymes that break down connective tissue..
Eventually it (_______) fills the joint, destroys articular cartilage and stretches (and at times ruptures)
attached tendons. The end result is permanent joint deformity.
Anti-inflammatory Cytokines
Soluble tumor necrosis factor receptor
Interleukin-1 receptor antagonist (IL-1ra)
Transforming growth fact B (TBF-B)
Interleukin 10 (IL-10
Pro-Inflammatory Cytokines
, Tumor necorsis factor alpha (TNF-a)
Interleukin 1, 2, 4 , 6, or 8
IFN-y, Granulocyte macrophage colony stimulating factor (GM-CSF)
TNF-a and IL-1
Play a significant role in the development of RA by producing substances that degrade tissues and
activate other inflammatory mediators. They also trigger the production of IL-6, IL-8 and GM-CSF as
well a s prostaglandins, osteoclasts and metalloproteinases at the cartilage/pannnus junction
Most Common Symptoms of RA
Pain, stiffness and swelling of the diarthrodial joints (moveable joints lined with synovium)
Most common joints affected by RA
PIP and MCP of the hands. MTP of the feet, wrists , elbows, shoulders, ankles and knees
PIP--proximal interphalangeal
MCP--metacrpophalangeal
MTP--metatarsophalangeal
Joints spared in RA
DIP(distal interphalangeal) joints of the fingers. This can be a distingishing feature from other arthritic
dz, particularly OA
Factors that effect the outcome of RA
A patient's ability to cope with the dz, his age, over level of fitness and the support of friends, family
and his medical team
3 Commonly used Labs used to dx and monitor RA
RF, Anti-CCP antibody for the ACPAs (98% specificty), and CRP
Rheumatoid Factor
a. sensitivity and specificity are 73% and 82%
b. can be present before symptoms
c. found in 75-80% of RA patients at some point in the course of the disease
d. associated with presence of HLA-DR4 molecule
Rheumatoid Nodules and Vasculitis are found in positive patients and there is increased risk of
systemic involvement and worse prognosis
e. Only 4% normal have RF
Other RF Rheumatic Diseases
a. Sjogren's syndrome (75-90%)
b. Mixed connective tissue disease (50-60%)
c. Systemic Lupus (15-35%)
Other RF Non Rheumatic Diseases
Also seen in non-rheumatic disorders, i.e Hepatitis, sarocidosis, malignancy, primary bilary cirrhois.
Because of this, it's limited as a predictor of RA.