Medical Laboratory Science Review
Harr. - 3.3 Immunology and Serology:
Infectious Disease EXAM STUDY
GUIDE 2026/2027 COMPLETE
QUESTIONS WITH VERIFIED
CORRECT ANSWERS || 100%
GUARANTEED PASS NEWEST
VERSION
Description:
Prepare thoroughly for your Clinical Immunology and Serology exams with this comprehensive
study guide for the years 2026 and 2027. This guide includes a detailed collection of the most
relevant and up-to-date questions, each accompanied by verified correct answers to ensure
you’re fully prepared for your exams. Topics covered range from antigen-antibody reactions to
key immunology techniques such as agglutination, precipitation, and immunodiffusion. You'll
find a wealth of essential terms, laboratory procedures, and diagnostic serology concepts that are
critical to mastering this field. This study guide also includes flashcards for quick revision,
making it easy to test your knowledge on the go. Designed to help you achieve a 100%
guaranteed pass, this newest version is the most complete and reliable resource for mastering
Clinical Immunology and Serology, giving you the confidence needed for success on exam day.
Keywords:
EXAM STUDY GUIDE 2026/2027, CLINICAL IMMUNOLOGY EXAM, SEROLOGY
EXAM STUDY, IMMUNOLOGY QUESTIONS, SEROLOGY QUESTIONS, GUARANTEED
PASS, VERIFIED ANSWERS, ANTIGEN ANTIBODY REACTIONS, AGGLUTINATION,
PRECIPITATION, IMMUNODIFFUSION, HYPERSENSITIVITY, LABORATORY
, PROCEDURES, AUTOIMMUNITY, DIAGNOSTIC SEROLOGY, MEDICAL EXAM
PREPARATION
1. Which serum antibody response usually characterizes the primary (early) stage
of syphilis?
A. Antibodies against syphilis are undetectable
B. Detected 1-3 weeks after appearance of the primary chancre
C. Detected in 50% of cases before the primary chancre disappears
D. Detected within 2 weeks after infection
B. Detected 1-3 weeks after appearance of the primary chancre
During the primary stage of syphilis, about 90% of patients develop antibodies between
1 and 3 weeks after the appearance of the primary chancre.
2. What substance is detected by the rapid plasma reagin (RPR) and Venereal
Disease Research Laboratory (VDRL) tests for syphilis?
A. Cardiolipin
B. Anticardiolipin antibody
C. Anti-T. pallidum antibody
D. Treponema pallidum
B. Anticardiolipin antibody
B Reagin is the name for a nontreponemal antibody that appears in the serum of
syphilis-infected persons and is detected by the RPR and VDRL assays. Reagin reacts
with cardiolipin, a lipid-rich extract of beef heart and other animal tissues.
3. What type of antigen is used in the RPR card test?
A. Live treponemal organisms
B. Killed suspension of treponemal organisms
C. Cardiolipin
D. Tanned sheep cells
C. Cardiolipin
Cardiolipin is extracted from animal tissues, such as beef hearts, and attached to
carbon particles. In the presence of reagin, the particles will agglutinate.
4. Which of the following is the most sensitive test to detect congenital syphilis?
A. VDRL
B. RPR
C. Microhemagglutinin test for T. pallidum (MHA-TP)
D. Polymerase chain reaction (PCR)
D. Polymerase chain reaction (PCR)
The PCR will amplify a very small amount of DNA from T. pallidum and allow for
,detection of the organism in the infant. Antibody tests such as VDRL and RPR may
detect maternal antibody only, not indicating if the infant has been infected.
5. A biological false-positive reaction is least likely with which test for syphilis?
A. VDRL
B. Fluorescent T. pallidum antibody absorption test (FTA-ABS)
C. RPR
D. All are equally likely to detect a false-positive result
B. Fluorescent T. pallidum antibody absorption test (FTA-ABS)
The FTA-ABS test is more specific for T. pallidum than nontreponemal tests such as the
VDRL and RPR and would be least likely to detect a biological false-positive result. The
FTA-ABS test uses heat-inactivated serum that has been absorbed with the Reiter
strain of T. pallidum to remove nonspecific antibodies. Nontreponemal tests have a
biological false-positive rate of 1%-10%, depending upon the patient population tested.
False-positive findings are caused commonly by infectious mononucleosis (IM), SLE,
viral hepatitis, and human immunodeficiency virus (HIV) infection.
6. A 12-year old girl has symptoms of fatigue and a localized lymphadenopathy.
Laboratory tests reveal a peripheral blood lymphocytosis, a positive RPR, and a
positive spot test for IM. What test should be performed next?
A. HIV test by ELISA
B. VDRL
C. Epstein-Barr virus (EBV) specific antigen test
D. Treponema pallidum particle agglutination (TP-PA) test
D. Treponema pallidum particle agglutination (TP-PA) test
The patient's symptoms are nonspecific and could be attributed to many potential
causes. However, the patient's age, lymphocytosis, and serological results point to
infectious mononucleosis (IM). The rapid spot test for antibodies seen in IM is highly
specific. The EBV-specific antigen test is more sensitive but is unnecessary when the
spot test is positive. HIV infection is uncommon at this age and is often associated with
generalized lymphadenopathy and a normal or reduced total lymphocyte count. IM
antibodies are commonly implicated as a cause of biological false-positive
nontreponemal tests for syphilis. Therefore, a treponemal test for syphilis should be
performed to document this phenomenon in this case
7. Which test is most likely to be positive in the tertiary stage of syphilis?
A. FTA-ABS
B. RPR
C. VDRL
D. Reagin screen test (RST)
A. FTA-ABS
The FTA-ABS or one of the treponemal tests is more likely to be positive than a
nontreponemal test in the tertiary stage of syphilis. In some cases, systemic lesions
, have subsided by the tertiary stage and the nontreponemal tests become seronegative.
Although the FTA-ABS is the most sensitive test for tertiary syphilis, it will be positive in
both treated and untreated cases
8. What is the most likely interpretation of the following syphilis serological
results?
RPR: reactive; VDRL: reactive; MHA-TP: nonreactive
A. Neurosyphilis
B. Secondary syphilis
C. Syphilis that has been successfully treated
D. Biological false positive
D. Biological false positive
A positive reaction with nontreponemal antigen and a negative reaction with a
treponemal antigen is most likely caused by a biological false-positive nontreponemal
test.
9. Which specimen is the sample of choice to evaluate latent or tertiary syphilis?
A. Serum sample
B. Chancre fluid
C. CSF
D. Joint fluid
C. CSF
Latent syphilis usually begins after the second year of untreated infection. In some
cases, the serological tests become negative. However, if neurosyphilis is present,
cerebrospinal fluid serology will be positive and the CSF will display increased protein
and pleocytosis characteristic of central nervous system infection.
10. Interpret the following quantitative RPR test results.
RPR titer: weakly reactive 1:8; reactive 1:8-1:64
A. Excess antibody, prozone effect
B. Excess antigen, postzone effect
C. Equivalence of antigen and antibody
D. Impossible to interpret; testing error
A. Excess antibody, prozone effect
This patient may be in the secondary stage of syphilis and is producing large amounts
of antibody to T. pallidum sufficient to cause antibody excess in the test. The test
became strongly reactive only after the antibody was diluted.
11. Tests to identify infection with HIV fall into which three general classification
types of tests?
A. Tissue culture, antigen, and antibody tests
Harr. - 3.3 Immunology and Serology:
Infectious Disease EXAM STUDY
GUIDE 2026/2027 COMPLETE
QUESTIONS WITH VERIFIED
CORRECT ANSWERS || 100%
GUARANTEED PASS NEWEST
VERSION
Description:
Prepare thoroughly for your Clinical Immunology and Serology exams with this comprehensive
study guide for the years 2026 and 2027. This guide includes a detailed collection of the most
relevant and up-to-date questions, each accompanied by verified correct answers to ensure
you’re fully prepared for your exams. Topics covered range from antigen-antibody reactions to
key immunology techniques such as agglutination, precipitation, and immunodiffusion. You'll
find a wealth of essential terms, laboratory procedures, and diagnostic serology concepts that are
critical to mastering this field. This study guide also includes flashcards for quick revision,
making it easy to test your knowledge on the go. Designed to help you achieve a 100%
guaranteed pass, this newest version is the most complete and reliable resource for mastering
Clinical Immunology and Serology, giving you the confidence needed for success on exam day.
Keywords:
EXAM STUDY GUIDE 2026/2027, CLINICAL IMMUNOLOGY EXAM, SEROLOGY
EXAM STUDY, IMMUNOLOGY QUESTIONS, SEROLOGY QUESTIONS, GUARANTEED
PASS, VERIFIED ANSWERS, ANTIGEN ANTIBODY REACTIONS, AGGLUTINATION,
PRECIPITATION, IMMUNODIFFUSION, HYPERSENSITIVITY, LABORATORY
, PROCEDURES, AUTOIMMUNITY, DIAGNOSTIC SEROLOGY, MEDICAL EXAM
PREPARATION
1. Which serum antibody response usually characterizes the primary (early) stage
of syphilis?
A. Antibodies against syphilis are undetectable
B. Detected 1-3 weeks after appearance of the primary chancre
C. Detected in 50% of cases before the primary chancre disappears
D. Detected within 2 weeks after infection
B. Detected 1-3 weeks after appearance of the primary chancre
During the primary stage of syphilis, about 90% of patients develop antibodies between
1 and 3 weeks after the appearance of the primary chancre.
2. What substance is detected by the rapid plasma reagin (RPR) and Venereal
Disease Research Laboratory (VDRL) tests for syphilis?
A. Cardiolipin
B. Anticardiolipin antibody
C. Anti-T. pallidum antibody
D. Treponema pallidum
B. Anticardiolipin antibody
B Reagin is the name for a nontreponemal antibody that appears in the serum of
syphilis-infected persons and is detected by the RPR and VDRL assays. Reagin reacts
with cardiolipin, a lipid-rich extract of beef heart and other animal tissues.
3. What type of antigen is used in the RPR card test?
A. Live treponemal organisms
B. Killed suspension of treponemal organisms
C. Cardiolipin
D. Tanned sheep cells
C. Cardiolipin
Cardiolipin is extracted from animal tissues, such as beef hearts, and attached to
carbon particles. In the presence of reagin, the particles will agglutinate.
4. Which of the following is the most sensitive test to detect congenital syphilis?
A. VDRL
B. RPR
C. Microhemagglutinin test for T. pallidum (MHA-TP)
D. Polymerase chain reaction (PCR)
D. Polymerase chain reaction (PCR)
The PCR will amplify a very small amount of DNA from T. pallidum and allow for
,detection of the organism in the infant. Antibody tests such as VDRL and RPR may
detect maternal antibody only, not indicating if the infant has been infected.
5. A biological false-positive reaction is least likely with which test for syphilis?
A. VDRL
B. Fluorescent T. pallidum antibody absorption test (FTA-ABS)
C. RPR
D. All are equally likely to detect a false-positive result
B. Fluorescent T. pallidum antibody absorption test (FTA-ABS)
The FTA-ABS test is more specific for T. pallidum than nontreponemal tests such as the
VDRL and RPR and would be least likely to detect a biological false-positive result. The
FTA-ABS test uses heat-inactivated serum that has been absorbed with the Reiter
strain of T. pallidum to remove nonspecific antibodies. Nontreponemal tests have a
biological false-positive rate of 1%-10%, depending upon the patient population tested.
False-positive findings are caused commonly by infectious mononucleosis (IM), SLE,
viral hepatitis, and human immunodeficiency virus (HIV) infection.
6. A 12-year old girl has symptoms of fatigue and a localized lymphadenopathy.
Laboratory tests reveal a peripheral blood lymphocytosis, a positive RPR, and a
positive spot test for IM. What test should be performed next?
A. HIV test by ELISA
B. VDRL
C. Epstein-Barr virus (EBV) specific antigen test
D. Treponema pallidum particle agglutination (TP-PA) test
D. Treponema pallidum particle agglutination (TP-PA) test
The patient's symptoms are nonspecific and could be attributed to many potential
causes. However, the patient's age, lymphocytosis, and serological results point to
infectious mononucleosis (IM). The rapid spot test for antibodies seen in IM is highly
specific. The EBV-specific antigen test is more sensitive but is unnecessary when the
spot test is positive. HIV infection is uncommon at this age and is often associated with
generalized lymphadenopathy and a normal or reduced total lymphocyte count. IM
antibodies are commonly implicated as a cause of biological false-positive
nontreponemal tests for syphilis. Therefore, a treponemal test for syphilis should be
performed to document this phenomenon in this case
7. Which test is most likely to be positive in the tertiary stage of syphilis?
A. FTA-ABS
B. RPR
C. VDRL
D. Reagin screen test (RST)
A. FTA-ABS
The FTA-ABS or one of the treponemal tests is more likely to be positive than a
nontreponemal test in the tertiary stage of syphilis. In some cases, systemic lesions
, have subsided by the tertiary stage and the nontreponemal tests become seronegative.
Although the FTA-ABS is the most sensitive test for tertiary syphilis, it will be positive in
both treated and untreated cases
8. What is the most likely interpretation of the following syphilis serological
results?
RPR: reactive; VDRL: reactive; MHA-TP: nonreactive
A. Neurosyphilis
B. Secondary syphilis
C. Syphilis that has been successfully treated
D. Biological false positive
D. Biological false positive
A positive reaction with nontreponemal antigen and a negative reaction with a
treponemal antigen is most likely caused by a biological false-positive nontreponemal
test.
9. Which specimen is the sample of choice to evaluate latent or tertiary syphilis?
A. Serum sample
B. Chancre fluid
C. CSF
D. Joint fluid
C. CSF
Latent syphilis usually begins after the second year of untreated infection. In some
cases, the serological tests become negative. However, if neurosyphilis is present,
cerebrospinal fluid serology will be positive and the CSF will display increased protein
and pleocytosis characteristic of central nervous system infection.
10. Interpret the following quantitative RPR test results.
RPR titer: weakly reactive 1:8; reactive 1:8-1:64
A. Excess antibody, prozone effect
B. Excess antigen, postzone effect
C. Equivalence of antigen and antibody
D. Impossible to interpret; testing error
A. Excess antibody, prozone effect
This patient may be in the secondary stage of syphilis and is producing large amounts
of antibody to T. pallidum sufficient to cause antibody excess in the test. The test
became strongly reactive only after the antibody was diluted.
11. Tests to identify infection with HIV fall into which three general classification
types of tests?
A. Tissue culture, antigen, and antibody tests
