Exam 2 Flashcards
What is the best temperature range for cold aggutinins to react
0C to 5C
Give 3 Examples of infections that my cause cold aggultinins to develop
- mycoplasma pneumonia
- infectious mononucleosis
- primary atypical pneumonia
Explain Desensitization
Process in which a hypersensitive animal is given several very small subcutaneous injections of antigen at closely-spaced intervals & may then be able to tolerate an ordinarily shocking dose without severe reaction.
Explain what the reactions mean in a Hemagglutination inhibition test (agglutination or the absence of aggulutination)
Agglutination = negative result, no antigen
No agglutination = positive result, presence of antigen
Remember, this is a test for inhibition!
The Nichols strain of T.pallidum is used in what type of testing
FTA-ABS
When do serum tests for syphilis usually become reactive
Between first and third week following appearance of primary lesion.
In secondary syphilis, would the serological tests performed to detect syphilis be positive, negative, have no diagnostic value, or are they not performed in that stage?
Test would be positive.
.
How long after treatment does the serological test become nonreactive in secondary syphilis?
Tests are nonreactive 12 months after treatment
The secondary stage of syphilis occurs how many weeks after the appearance of the primary chancre?
6 to 8 weeks after the first chancre
Name three pharmacologically active mediators of anaphylaxis.
- Histamine
- Tryptase
- ECFA
- Neutrophil chemotactic factor
- Chimase
Which of the following is true about the late latent stage of syphilis: it is highly contagious, usually noncontagious, not detectable by serological tests, or not communicable between mother and fetus?
Usually noncontagious
P24 is a viral antigen that is the first to be detected in which potentially deadly virus?
HIV - used for viral load testing
Name three means of transmission of the HIV virus
- Body fluids
- Sexual activity
- Mother to fetus
Needles that dispense antigen for the VDRL test must be calibrated to deliver how much? How often should the needle be QC’d?
1/60 mL
QC’ed each batch
T. pallidum crosses the placenta in which week of gestation?
18th week
What does the FTA-ABS test identify in the patient’s serum?
- treponemal antibodies
What does the fluorescein labeled antihuman globulin do for the purposes of interpreting this test?
- anti-human globulin makes the antigen-antibody reaction visible
In the direct fluorescent antibody test, the ______________ is “labeled” with fluorescent dye.
Antibody
The serum is inactivated to destroy complement in the VDRL or the RPR?
VDRL
Give 5 examples of an autoimmune disease and describe whether it is organ-specific and, if so, which organs are affected or if it is systemic.
ORGANIC SPECIFIC
-myasthenia gravis - nerve/muscle synapse
-Addison’s - adrenal glands
-Insulin dependent diabetes mellitus - pancreas
-MS - myelin sheath on axons of neural cells
-Grave’s - thyroid
SYSTEMIC:
-SLE - Lupus
-RA - both systemic & organ-specific - joints
A flat-bottomed bottle is required in the VDRL or the RPR?
VDRL
Explain a flocculation test and give examples of this type of testing
Specific type of precipitation that occurs over a narrow range of antigen concentrations e.g. VDRL & RPR
The VDRL or the RPR is always read macroscopically?
RPR
A modified VDRL antigen is used in what type of testing?
RPR - has addition of charcoal particles
Name some synonyms for Type B viral hepatitis
Serum hepatitis Hepatitis B Hep B Viral hepatitis HBV
What is a chancre?
Primary inflammatory lesion of primary syphilis.
In order to properly perform the RPR test, the rotator speed should be _____ rpm.
100 rpm
Why do you get false negative results with a Postzone reaction?
The quantity of antigen exceeds the quantity of antibody.
Why would you get false negative results with a Prozone reaction?
The quantity of antibody exceeds the quantity of antigen.
Explain the zone of equivalence
Antibody and antigen are precipitated to the max.
What is tannic acid used for in serologic testing?
Allows proteins to complex with RBCs as antigen carriers (converts hemolytic reactions to agglutination reactions).
- What is serum sickness?
Reaction caused by injection of therapeutic foreign serum usually made from horse or cow. (found in tetanus, diphtheria, gangrene)
How does the Western blot test differ from ELISA tests?
ELISA is a screening test since it tests HIV 1 & 2 together.
W.B. uses antibody to individual antigen for specific identification so is confirmatory.
What is an agglutinin?
Substance that causes particles to coagulate to form a thickened mass. Can be antibodies that cause antigens to aggregate by binding to the antigen-binding sites on the antibodies.
Why is cholesterol added to the antigen that is used in the flocculation test for syphilis?
Cholesterol is the absorption center for tissue lipids.
T or F Treating a pregnant woman does not cure the fetus.
False
T or F Congenital, primary, and secondary syphilis are best treated by repeated doses of penicillin.
False
T or F Treatment does not alter any tissue damage that has already occurred.
True
T or F It is necessary to get repeated blood tests for 5 years following treatment
False
T or F Tertiary syphilis cannot be treated
False
Loss of self tolerance results in what type of disease?
Autoimmune
Explain cross reactivity and what kind of results it can lead to.
Antigens that are closely related in structure can cause false positive results.
The antibody to tissue lipids is called __________.
Reagin
The presence of anti-double stranded DNA can distinguish RA from what other autoimmune disease?
SLE (Lupus)
Recent experience or exposure to group A hemolytic Streptococci can be detected when there are high or steadily increasing concentrations of what in a patient’s serum
ASO (anti-streptolysin O)
Define anaphylaxis
Severe systemic allergic reaction that results when the organs involved are primarily blood vessels and smooth muscles of the circulatory system.
What is a xenograft? This is also known as what?
Transplant of tissue from one species to another.
aka Heterograft
Transplanting from one individual to a genetically nonidentical person of the same species is called what (give both names for it)?
Homograft
aka Allograft
Define contact dermatitis. Give 3 examples of things that can cause this.
A hypersensitive reaction caused by direct contact of a substance to the skin, usually resulting in an itchy rash.
- Metals
- Drugs
- Plants
Which type of test is most widely used to detect HIV?
Screening: ELISA
Of Hep C, HIV, Hep G, and Hep B, which is the most virulent?
Hep C is most virulent.
Can you explain why Hep C is more dangerous than Hep B?
Hep C is more dangerous because 85% of cases convert to chronic hepatitis, versus 10% for Hep B.
What is the first antigen to appear in the serum of a person infected with HBV?
Hep B surface antigen
How is Hepatitis A transmitted?
oral-fecal
Type IV hypersensitivity is the only type that involves __________.
T-Cells
T or F Testing for the p24 antigen would be useful as a screening test for blood products
False
On average, it takes ______ to _______ weeks for an individual to develop HIV antibodies after exposure to HIV.
6 to 12
What antibody appears in the serum of individuals that have recovered from Hepatitis B or who have received the Hepatitis B vaccination?
Hep B Surface Antibody aka HBsAb (anti-HbsAg)
Which form of hepatitis is responsible for the most post-transfusion reactions?
Hep C
If a patient has an immune response to his/her own IgG, they would most likely have a positive or negative RA test?
Positive
Which set of antigens would be represented on a positive Western blot?
GP41
GP120
- The antigen in a precipitin reaction must be ___________?
soluble
What does ANA stand for? How is testing for this useful?
Anti-nuclear Antibody
Found in >95% SLE patients.
What does HLA stand for and why is it important?
Human Leukocyte Antigen
Most important immunologic barrier to the survival of transplanted organs and tissues.
Which hepatitis virus requires HBV infection?
Hep D
Briefly explain Graves’ Disease
hypothyroidism
tacacardia
Increased T3 and T4 and decreased or absent TSH
Within which organ is it thought that potentially self-reactive lymphocytes are removed
Thymus
When discussing EBV and infectious mono, name the primary mode of transmission.
saliva
What % of lymphs would you expect to see as atypical on a peripheral blood smear
10%
Which Malignancy has been associated with EBV
Lymphoma
Hodgkins
Parkins
Which virus have most people been exposed to by their elderly years
CMV
Name some examples of anti-retro-viral drug therapies, and How do they work
suppress viruses replication
inhibitors
Which cells are the main target for the HIV virus?
Why?
T Cells, becuase of CD4 Markers
What is one method for determining the progression to the AIDS stage of HIV infection.
How is this done (gold standard)
CD4 count lower than 200 per micro liter
Flow
Shingles is essentially a re-emergence of what virus?
Verisallous Oster (chicken pox)
Regarding HIV transmission, which specimens are not considered infectious unless visibly blood
Urine
Sweat
Vomit
Tears
In the HIV virus, what is reverse transcriptase responsible for doing?
transcribing viral RNA to DNA
Name the gene that codes for the enzymes necessary for HIV replication.
pol gene
Briefly describe the latency period of HIV infection. What is the median length of time this can last?
decrease birhemia, subtle or absent symptoms
gradual deterioration of immune system
lasts about 10 yrs
Symptoms of primary infection of HIV are similar to symptoms from what other virus?
Mono
List the advantages and disadvantages of chemiluminescent assays.
Precupitation Reactions SLIDE
Briefly describe the methodology of turbidimetry.
measure of cloudiness of solution
measures the reduction of light intensity
due to reflection absorption and scatter
Briefly describe nephlometry.
measures the light that is scattered at a particular angle from the incident beam as it passes though A suspension
The antibody that is rheumatoid factor belongs to which Ig class?
IgM
What is the test anti-CCP and what is it used for?
Cyclic Citrillunated Peptide
lead marker for RA more sensitive for RF
What is precipitation
is combining soluble antigen with soluble antibody, to produce insoluble complexes that are visible
Bonus*
What type of testing is appropriate for what stages of syphilis
-Congenital 1 & 2 is best treated with a single injection of a long-acting penicillin
-3rd Degree of syphilis requires therapy for longer periods
-
Bonus*
What are all of the causative agents for hepatitis
dfg
Bonus*
Some of the organ-specific autoimmune diseases and specifically which organs or areas they affect
sfg
Bonus*
The full names of the VDRL and RPR tests
dfg
