Rheumatoid factor and Widal Test Flashcards
measures the amount of rheumatoid factor in your blood
RHEUMATOID FACTOR TEST
is commonly present and circulating around your body
Rheumatoid factor
These are also
inflammatory factors like your CRP.
Rheumatoid factor
RF drawback
nonspecific
Common signs and symptoms of increase RF
Joint pains,
joint stiffness, fatigue, swelling
are proteins produced by your
immune system that can attack healthy tissue inyour body.
Rheumatoid factors
are also immunoglobulins/antibodies)
Rheumatoid factors
They can attack healthy joints, glands or other normal cells by mistake
Rheumatoid factors
RF attacks
healthy joints, glands or other normal cells by mistake
Why RF attacks
autoimmune
aside from rheumatoid arthritis you can also have
Scleroderma,
Juvenial idiopathic diabetes,
Sjorgen
High levels of Rheumatoid factor in the blood are most often associated with autoimmune diseases such as:
- Rheumatoid arthritis
- Sjorgen’s syndrome
rheumatoid factor may be detected in some
_______, and people with _______ sometimes have normal levels of rheumatoid factor
healthy people; autoimmune diseases
T or F
Is it necessary and ideal to pair your RF testing with the other testing procedures?
T
is one of the group of blood
tests primarily used to help pinpoint a diagnosis of Rheumatoid arthritis.
rheumatoid factor test
OTHER TESTS FOR RHEUMATOID FACTOR ARTHRITIS
a) Anti – nuclear antibody test (ANA) (also for
Systemic Lupus Erythematosus)
b) Anti – cyclic citrullinated peptide (anti – CCP) antibody test
c) C- reactive protein test (CRP)
d) Erythrocyte sedimentation rate (ESR)
T or F
The amount of rheumatoid factor in your blood does not helps the physician choose the treatment approach that will
work best for the situation.
False
It does help the physician
T or F
Types of medications recommended by your doctor will depend on the severity of your signs and symptoms or the duration
T
Normal Range of RF
<20 IU/mL
Treatments
- NSAIDS (Non-steroidal Anti-Inflammatory Drugs)
- Corticosteroids
- Prednisone
- DMARDS (Disease Modifying Anti-Rheumatic Drugs)
use to reduce inflammation and pain of joints
Prednisone
Can slow the progression of rheumatoid arthritis and save the joints and other tissues from permanent damage
DMARDS (Disease Modifying Anti-Rheumatic Drugs)
HOME REMEDIES for RF
Exercises
Applying heat and cold pressures
Relax to reduce stress level
easing the pain and relaxing the tense and painful muscles
Heat
numb portions of the joint that is being inflamed and to reduce swelling
Cold
a type of autoimmune disorder that causes pain, swelling, and stiffness of the joints.
Rheumatoid arthritis
used to help diagnose Rheumatoid arthritis or other autoimmune disorders
RF
RF can also aid in diagnosing
Leukemia, and tuberculosis
Rheumatoid factors (RF) are
-IgM directed against IgG (FC portion)
-Detected using rapid tests
-75% to 85% or patients with Rheumatoid arthritis have elevated serum RF
-RF can be present in other conditions
tailed portion responsible for biological activities such as activation of your Immune system
FC portion
FAB portion
enables the binding of antigen
T or F
IgM undirected against the FC portion of IgG that’s for RF and once reacted it will form an immune complex and will proceed to auto immune disorders such as inflammatory arthritis
False; directed
Detected using rapid tests
Principle:
RF Slide Agglutination
T or F
74% to 83% or patients with Rheumatoid arthritis have elevated plasma RF
False; 75% to 85%; Serum RF
T or F
RF can be present in other conditions
T
Rheumatoid factor in other conditions:
give at least 3
Lupus
Sjorgen’s syndrome
Juvenile arthritis
Scleroderma
Mononucleosis
Tuberculosis
Certain cancers, such as leukemia or multiple myeloma
T or F
About 30 percent of people with rheumatoid arthritis have little or no rheumatoid factor in their blood.
F; 20%
is not used to diagnose osteoarthritis.
RF test
both affect the joints, they are very different
diseases
rheumatoid arthritis and osteoarthritis
an autoimmune disease.
Rheumatoid arthritis
T or F
Rheumatoid arthritis affects people at any age, but usually occurs between the ages of 41 and 60.
F; 40 and 60
T or F
Rheumatoid arthritis affects more women than men
T
is not an autoimmune disease.
Osteoarthritis
It is caused by the wear and tear of joints
(degenerative) over time and usually affects adults over the age of 65.
Osteoarthritis
Differentiate Rheumatoid Arthritis and Osteoarthritis
Rheumatoid Arthritis
-Affects multiple joints
-Autoimmune
-Express other conditions
-Immunosuppressant drugs
Osteoarthritis
-Affects one specific joint
-Degenerative
-Cannot express other
manifestations
-Therapy
PRINCIPLE OF RF SLIDE TEST
Latex Agglutination
Latex Agglutination
-Reagent is IgG – coated latex particles
-Combine patient serum with latex reagent
-Observe for agglutination
-RF (IgM) will cause agglutination
is a positive (+) result
Agglutination
Little or no Rheumatoid
Factor in blood but would not rule out that you do not have RA or other medical conditions
Negative or Normal Results
Higher Level of RF is found in blood
(>20 IU/mL) but doesn’t always mean that the RF is causing your symptoms
Positive Result
T or F
Conditions other than Rheumatoid arthritis can cause positive results
T
___% - ___% of RA patients can be negative for RF
15% - 25%
Note:
Remember that RF test is not specific for RA; Other conditions can have increase RF; Other tests can be used to follow disease course
is a serological method to diagnose enteric or typhoid fever that is cause by the infection with pathogenic microorganisms like Salmonella typhi, Salmonella paratyphi a, b and c
Widal test
In Widal test
The method of diagnostic test is based upon ______________ specifically prepared from Salmonella species
agglutination (clumps) reaction between antibodies of patient serum and antigens
Salmonella possess the following (3) three antigens
Flagellar antigen or H antigen
Somatic antigen or O antigen
Surface antigen or Vi antigen
composed of proteins, heat labile and sensitive, antibody formation are rapid and sustained, highly immunogenic, antibody level persists for a longer period.
Flagellar antigen or H antigen
composed of polysaccharide, heat stable and alcohol resistant, antibody formation are rapid but only on a early phase, less immunogenic, antibody level falls off quickly
Somatic antigen or O antigen
surface polysaccharide envelope covering the O antigen. This antigen is expressed only on few ser types and renders the bacilli inagglutirable with O antiserum. The name is believed that Vi is related to virulence.
Surface antigen or Vi antigen
measures agglutination antibodies directed against a Salmonella O somatic surface antigen and/or a Salmonella H flagella antigen of the suspected organism
Widal test
Widal test measures agglutination antibodies directed against a ______somatic surface antigen and/or a ______flagella antigen of the suspected organism
Salmonella O; Salmonella H
detects antibodies against O and H antigens.
Widal test
Widal test detects antibodies against
O and H antigens.
Uses direct agglutination
Widal test
First discovered by Fernand Widal in 1896
Widal Test
Who discovered Widal Test
Fernand Widal in 1896
Widal test
CLINICAL MANIFESTATIONS
Chest congestion
Constipation
Diarrhea
Gastroenteritis
Headache
Body malaise
High temperature
Loss of appetite
Stomach pains
Note:
Widal test is already pa phase out and the gold standard for detecting typhoid fever is Blood culture for Salmonella typhii solation.
Other test: Typhidot
MODES OF TRANSMISSION
- Ingestion of contaminated food or water
- Rarely, from person to person
- Fecal – oral route
- Most of the time carriers come from food handlers
SERODIAGNOSIS OF TYPHOID
Widal test by Rapid Slide
(Screening) test =1 min
Widal test by Tube
Agglutination test= 2-4 hours
Typhidot test (IgG/IgM rapid test) =15 minutes
ELISA = 45 minutes – 2 hours
Electrochemiluminiscent immunoassays
= 45 minutes – 2 hours
PCR (Polymerase chain
reaction)
= 7-10 days
Antibody in the serum produced in response to Salmonella organism, the kit contains antigen suspensions that are killed bacteria and they were stained to enhance the reading of agglutination tests.
PRINCIPLE OF WIDAL TEST
Color of Stains
Blue
Red
stained organisms – specific to somatic
antigens (O antigen)
Blue
stained antigens - specific to the flagella
antigens (H antigen).
Red
WIDAL KIT INCLUSIONS
1) Positive control vial
2) Negative control vial
3) Package insert
4) White glass slide
5) Stirring sticks
contains no antibodies against the specific bacteria
Widal negative control (-)
contains ready to use standardized (goat antiserum) with polyspecific antibodies having specific reactivity towards S. typhi O and H antigens and is useful in the validation of the performance of Widal reagents.
Widal positive control (+)
The widal positive control contains ready to use standardized
goat antiserum
should be run with
each test
positive and negative control
T or F
if the reagent falls to agglutinate with the positive control, or dose agglutinate with the negative control, continue the test
F; it should be discarded or review the procedure and repeat the test with a new test kit.
LIMITATIONS
The Widal test has
-very low specificity
-less sensitive
-confusing
-difficult to interpret for the diagnosis of typhoidfever
Why is it difficult to interpret for the diagnosis of typhoid fever
because cross – agglutinating antibodies remaining from the past infections with related salmonella serotypes give false positive results.
T or F
Furthermore, in areas where fever due to infections is a common occurrence. So false positive reactions may occur as a result of non-typhoid
T
CAUSES OF FALSE POSITIVE WIDAL AGGLUTINATION TEST
-Previous immunization with Salmonella antigen
-Cross – reaction with non typhoid salmonella
-Variability and poorly standardized commercial antigen preparation kit.
-Infection with malaria
-Other Enterobacteriaceae sharing the same Endotoxins/lipopolysaccharides
is an old serologic assay and no longer performed in many developed countries
Widal test
WHY WIDAL TEST IS STILL USED?
because of its low cost and limited resources which releases results in a short period of time.
is one of the best, easily accessible, cheap and simple method for the diagnosis of typhoid fever
Widal Test
PROPHYLAXIS
-Simple hand hygiene and washing can reduce several cases of typhoid
-All milk and dairy products should be pasteurized
-Avoid drinking untreated water
-Avoid raw fruits and vegetables
-Screening of food handlers for S. typhi
-Vaccines
