Rheumatoid arthritis is a chronic systemic disease of unknown etiology. lt is
frequently characterized by swelling and pain in the joints and by inflammatory
and degenerative processes involving cartilage, synovial membrane or muscle
tissue. The disease is widespread in the United States and throughouthe
world, and is found in all age groups. Most typically, its onset is in young adults
in their thirties and forties. While no specific cure has yet been found, early
therapy is of great value in halting or minimizing irreversible damage to the
joints. For this reason prompt diagnosis is of great importance.
A characteristic of rheumatoid arthritis is the presence in the Hood and in
synovial fluid of a reactive group of proteins called Rheumatoid Factor. t’3 These
are macroglobulins having a molecular weight of 1 million. In the opinion of
many investigators, the Rheumatoid Factors are antibodies direded against
“altered” human gamma globulins.l,5’6 The Rheumatoid Factors are found in
70-10Qo/o of cases of definite rheumatoid arthritis depending on the test
procedure used to detect them. Because of this widespread incidence of RF,
its demonstration isa usefulaboratory criterion for the diagnosis of suspected
rheumatoid arthrjtis. By comparison the occurrence of RF in arthritis or
rheumatic fever is less than 2 and 3% respectively. lt should be noted that
incidence of RF have been reported in a variety of nonrheumatic diseases
such as pulmonary tuberculosis, bacterial endocarditis and syphilis as well as
others. A significant incidence of RF in the aged has also been observed.
Since the discovery of RF, there have been many techniques developed to
identify and quantitate these factors. The most generally useful techniques
have been agglutination procedures employing polystyrene particles coated
with a layer of absorbed human gamma globulin.T The RF present in a test
serum reacts with the coating material causing a visible agglutination of the
inert latex particles. lt is this reaction which is the basis of the CENOGENICS’
RFTEST.
CENOGENICS’RFTEST SET for the detection of Rheumatoid Factors rapidly
and accurately identifies the presence of RF, one of the criteria for the diagnosis
of rheumatoid arthritis.
In the presence of Rheumatoid Factor positive antiserum, CENOGENICS’
latex-globulin RF reagent can be used to demonstrate agglutination both
qual itatively and quantitatively.
PRINCIPLES OFTHE PROCEDURE
The principle of the test is an immunologic reaction between the Rheumatoid
Factor (RF), a macromolecular molecule globulin found in serum and the
corresponding lgG coated onto finely dispersed polystyrene latex particles