RH LATEX AGGLUTINATION TEST

Question 2

*MATERIALS for rheumatoid factor latex agglutination test

Answer 2

• Rf latex suspension
• Positive and Negative Controls
• Black test cards
• Disposable stirrers
• Mechanical rotator

Question 3

Principle of the test

Answer 3

*The RF reagent is a suspension of polystyrene latex particles sensitized
with specially prepared human IgG.

The reagent is based on an immunological reaction between human IgG
bound to biologically inert latex particles and rheumatoid factors in the
test specimen. When serum containing rheumatoid factors is mixed
with the latex reagent, visible agglutination occurs.

Question 4

The RF latex reagent sensitivity has been adjusted to detect a minimum
of ___ of rheumatoid factors

Answer 4

8 IU/mL

Question 5

RF Latex Reagent

Answer 5

A suspension of uniform polystyrene
particles coated with IgG (human) in glycine buffer, pH 8.2

Question 6

buffer and the pH used in the rheumatoid factor latex reagent

Answer 6

Glycine-Saline Buffer - pH 8.2 ± 0.1M glycine and 0.15M
NaCl

Question 7

should we MIX WELL BEFORE USING?

Answer 7

yes

Question 8

RF Positive Control Serum

Answer 8

A stabilized, prediluted human
serum containing at least 8 IU/mL of RF

Question 9

RF Negative Control Serum:

Answer 9

A stabilized, prediluted human
serum containing less than 8 IU/mL of RF

Question 10

*RA is another example of a systemic autoimmune disorder. It affects about
___ of the adult population,

Answer 10

0.5% to 1.0%

Question 11

do prevalence varies with ethnicity
and geographic location?

Answer 11

yes

Question 12

which gender is 3 times more likely to be affected by RA?

Answer 12

women

Question 13

the prevalence of the disease is highest in women who are
more than ___ years of age.

Answer 13

65

Question 14

RA can be characterized as a
___, ___, and ___ arthritis of
the peripheral joints

Answer 14

chronic, symmetric, and erosive

Question 15

RA can as well affect multiple organs such as

Answer 15

heart and the lungs

Question 16

Associations of RA with more than ___ genetic regions have
been discovered.

Answer 16

30

Question 17

The strongest associations have been between a subset of patients with RA and specific ___alleles/gene

Answer 17

HLA-DRB1 alleles or PTPN22 gene
polymorphisms

Question 18

The strongest
environmental risk factor for RA is believed to be ____, which
doubles the risk of developing the disease

Answer 18

cigarette smoking

Question 19

The pathology of RA is caused by an inflammatory process that results in the destruction of ___ and ___.

Answer 19

bone and cartilage

Question 20

The lesions in rheumatoid joints show an increase in
cells lining the synovial membrane and formation of a ___

Answer 20

pannus

Question 21

a sheet of inflammatory granulation tissue that
grows into the joint space and invades the cartilage

Answer 21

pannus

Question 22

*Infiltration of the inflamed synovium with ___s
within the joint

Answer 22

T and B lymphocytes, plasma cells, dendritic cells, mast cells, and granulocytes

Question 23

*It is not known what role autoantibodies play in the initiation of the
inflammatory response.

Two key antibodies found in the disease are ___ and ___

Answer 23

RF and anti-CCP.

Question 24

*RF is an antibody that is most often of the ____ class and is directed against
the FC portion of ___

Answer 24

IgM; IgG

Question 25

It has been postulated that RFs may play a role in the pathogenesis of RA by increasing ___ activity and enhancing antigen presentation to T cells by ___.

Answer 25

macrophage; APCs

Question 26

*The complement protein __ binds to the immune complexes, activating the classical complement cascade

Answer 26

C1

Question 27

The complement protein C1 binds to the immune complexes, activating the classical complement cascade. During this process,___and __ are generated, which act as chemotactic factors for neutrophils and macrophages.

Answer 27

C3a and C5a

Question 28

Diagnosis of RA is based on a combination of ___

Answer 28

clinical manifestations, radiographic findings, and laboratory testing.

Question 29

*___ is the antibody that is most often tested to aid in making the initial diagnosis.

Answer 29

RF

Question 30

Approximately__ of patients with RA test positive for RF.

Answer 30

70% to 90%

Question 31

a negative result does not rule out the presence of RA. true

Answer 31

true

Question 32

Conversely, a positive test result is not specific for RA because RF is also present in about ___ of healthy individuals

Answer 32

5%

Question 33

Conversely, a positive test result is not specific for RA because RF is also present in about 5% of healthy individuals and in ___ of those over the age of 65

Answer 33

10% to 25%

Question 34

RF can be found in patients with other connective tissue diseases such as

Answer 34

SLE, Sjögren’s syndrome, scleroderma, and mixed connective tissue disease, as well as in people with some chronic infections

Question 35

*Manual agglutination tests using __ have been used for many years to detect RF

Answer 35

charcoal or latex particles coated with IgG

Question 36

manual agglutination test using charcoal or latex particles, These tests, however, only detect the __ isotype

Answer 36

IgM

Question 37

manual agglutination test, this kind of test found the IgM isotype in about _% of patients

Answer 37

75%

Question 38

Manual agglutination tests have been largely replaced by ___ which are automated, have greater precision and sensitivity, and can also detect other RF isotypes

Answer 38

ELISA, chemiluminescence immunoassay, and nephelometric methods

Question 39

*Once a diagnosis of RA is made, the most helpful tests for following the progress of the disease are ___

Answer 39

general indicators of inflammation

Question 40

general indicators of inflammation such as measurement of ___

Answer 40

ESR, CRP, and complement components.

Question 41

Typically, __ and ___ are elevated and the levels of serum complement components are NORMAL or increased because of increased acute-phase reactivity

Answer 41

CRP and ESR

Question 42

___ levels correlate well with disease activity because levels reflect the intensity of the inflammatory response

Answer 42

CRP

Question 43

Results should be read within minutes after the mixing or the reagent on the slide

Answer 43

two (2)

Question 44

Existence of prozone at high titers has not been encountered. true or false

Answer 44

true

Question 45

Increased levels of RF may be found in some diseases other than rheumatoid arthritis such as ____

Answer 45

infectious mononucleosis, sarcodosis, lupus erythematosus, Sjogren's syndrome.

Question 46

Certain patients with rheumatoid arthritis will not have the RF present in their serum true or false?

Answer 46

true

Question 47

The diagnosis of rheumatoid arthritis is based largely on __

Answer 47

clinical examination

Question 48

The diagnosis of rheumatoid arthritis is based largely on clinical examination, but ___ are useful to support the clinical diagnosis and to evaluate the severity and course or the disease in the individual patient.

Answer 48

laboratory tests

Question 49

One of the most useful clinical markers for rheumatoid arthritis is ___r in serum.

Answer 49

rheumatoid factor

Question 50

___ is a term used to describe a variety of antibodies or immune complexes or both, that occur with rheumatoid arthritis as well as in a variety of other diseases.

Answer 50

Rheumatoid factor

Question 51

Different studies have shown positive serological reactions for rheumatoid factor in as high as ___ of patients with rheumatoid arthritis compared with less than 5% in control groups

Answer 51

90%

Question 52

Reagents are stable until stated expiration date on bottle label when stored refrigerated ___.

Answer 52

(2 - 8°C)

Question 53

can we freeze the reagent while storing?

Answer 53

nope, DO NOT FREEZE

Question 54

The RF latex reagent, once shaken must be ___

Answer 54

uniform without visible clumping

Question 55

When stored refrigerated, a slight ___ may occur and should be considered normal

Answer 55

sedimentation