IMM chapter 21
A patient presents with a painless genital ulcer. The patient is then diagnosed as having syphilis. In what stage of syphilis is the patient?A) PrimaryB) SecondaryC) LatentD) Tertiary
Primary
At which stage of syphilis is the RPR the most sensitive?
Primary
RPR stands forA) reagin plasma reactiveB) reactive phosphate reagentC) rapid plasma reaginD) random positive reagin
rapid plasma reagin
The antibody called regain that is found in syphilis:
reacts with cardiolipin
a 25 year old patient presents with a fine rash on his chest, palms, and feet; fever; and malaise. The RPR is reactive with a titer of 1:64, the VDRL is nonreactive, and the TP-PA is positive. What is the diagnosis?
secondary syphilis
which of the following is a cause of a biological false-negative result In the nontreponemal tests for syphilis?
secondary syphilis
which of the following is true of nontreponemal antibodies?
these antibodies are directed against cardiolipin
treponemal EIA tests for syphilis are characterized by all of the following except
they are useful in monitoring antibody titers in syphilis patients undergoing therapy
The RPR and VDRL tests differ from each other in which of the following ways?A) method for reading or visualizing the reactionB) specificity of antibody detectedC) specificity of antigen detectedD) principle for detecting antigen-antibody complexes
A) method for reading or visualizing the reaction
Lab results on a patient indicated a positive RPR and a negative FTA. The patient had no obvious sore, rash, or other symptoms. What is the most likely cause of these results?A) Primary syphilisB) Secondary syphilisC) Tertiary syphilisD) Another disease, such as mono
Another disease, such as mono
Which vectors transmit Borrelia burgdorferi from natural reservoirs to humans?
Bites of soft-bodied ticks
On what basis would Treponema pallidum and Borrelia burgdorferi be distinguished from each other?
Only B burgdorferi can be grown in the laboratory on artificial media
Patient serum is mixed with sheep red blood cells that have been sensitized with Treponema pallidum antigens as well as with unsensitized red blood cells in a separate well. Agglutination was observed in the well with sensitized red blood cells and not in the well with unsensitized red blood cells. What is the interpretation of these results?A) Positive for anti-Treponema pallidum antibodiesB) Positive for heterophile antibodiesC) Negative for anti-Treponema pallidum antibodiesD) Negative for anticardiolipin antibodies
Positive for anti-Treponema pallidum antibodies
A patient presents with a painless genital ulcer. The patient is then diagnosed as having syphilis. In what stage of syphilis is the patient?
Primary
In an indirect fluorescent immunoassay such as the FTA confirmatory test for syphilis, all of the following are true EXCEPT:A) A labeled antigen is used.B) Washing is an important step.C) Patient antibody is detected.D) Antihuman globulin has a fluorescent tag.
A labeled antigen is used.
A laboratory test that is used to confirm syphilis and detects specific treponemal antibodies is:A) VDRLB) MHA-TPC) RPRD) monotest
B) MHA-TP
A patient is suspected of having latent syphilis. Which set of test results for RPR, MHA-TP, and CSF-VDRL best confirms this diagnosis?A) RPR = R-8 dils; MHA-TP = reactive; VDRL = R-4 dilsB) RPR = nonreactive; MHA-TP = reactive; VDRL = nonreactiveC) RPR = nonreactive; MHA-TP = nonreactive; VDRL = nonreactiveD) RPR = R-2 dils; MHA-TP = nonreactive; VDRL = nonreactive
B) RPR = nonreactive; MHA-TP = reactive; VDRL = nonreactive
Lyme disease is caused by:A) Treponema pallidumB) Borrelia recurrentisC) Leptospira autumnalisD) Borrelia burgdorferi
Borrelia burgdorferi
What is the target of the antibody called reagin that is found in syphilis?
Cariolipin
Which of the following is a cause of a laboratory-induced false-negative in the screening tests for syphilis?A) Alcohol ingestion prior to blood drawB) Systemic lupus erythematosusC) Excess serumD) Hot laboratory
Excess serum
Which of the following is a test for specific treponemal antibody?A) VDRLB) RPRC) FTA- ABSD) All of the above
FTA- ABS
which syphilis test detects specific treponemal antibodies?
FTA-ABS
A new technologist is busy one night and has to perform an RPR on a serum sample. He does not calibrate the needle delivering the antigen and the needle is delivering a larger volume of antigen than it is supposed to. What kind of error can this cause on the test result?A) Laboratory-induced false-negative due to postzoneB) Laboratory-induced false-positive due to prozoneC) Biological false-positiveD) biological false-negative
Laboratory-induced false-negative due to postzone
Which of the following is a cause of a biological false-negative in the screening tests for syphilis?A) Rotated too longB) Rheumatoid arthritisC) Latent syphilisD) Low rotator speed
Latent syphilis
At which stage of syphilis is the RPR specific for syphilis?A) PrimaryB) SecondaryC) TertiaryD) LatentE) None of these
None of these
A patient is diagnosed with syphilis. Which laboratory tests can be used to monitor the effectiveness of therapy in this patient?
RPR
A patient is diagnosed with syphilis. Which of the following laboratory tests can be used to monitor the effectiveness of therapy in this patient?A) RPRB) MHA-TPC) C-reactive proteinD) Mono test
RPR
At which stage of syphilis is the RPR the most sensitive?A) PrimaryB) SecondaryC) TertiaryD) Latent
Secondary
A 32-year-old heterosexual male presents to the physician with a 3-day history of multiple skin lesions located all over his body and on his mucous membranes. He hasn't felt well and has a low-grade fever. The patient cuts down trees in Massachusetts for a living. He is single, has had multiple sex partners, and does not use condoms. Here are the results of his laboratory tests: rapid plasma reagin = reactive 1:128; Treponema pallidum-particle agglutination assay = reactive; Borrelia burgdorferi IgM = < 1:8; Rickettsia rickettsii IgM < 1:8. This patient has:A) Primary SyphilisB) Secondary SyphilisC) Lyme DiseaseD) Rocky Mountain spotted fever
Secondary Syphilis
A 25-year-old patient presents with a fine rash on his chest, palms and feet, fever and malaise. The RPR is reactive with a titer of 1:64, the VDRL is non-reactive, and the MHA-TP is positive. What is the diagnosis?A) Primary syphilisB) Secondary syphilisC) Tertiary syphilisD) Latent syphilis
Secondary syphilis
A laboratory test that is used to confirm syphilis and detects specific treponemal antibodies is:
TP-PA
A patient presents with personality changes, altered mental state, and delusions of grandeur. The patient is then diagnosed as having syphilis. In what stage of syphilis is the patient?A) PrimaryB) SecondaryC) LatentD) Tertiary
Tertiary
Which two-tier testing procedure for Lyme disease does The Centers for Disease Control and Prevention recommend?
The recommendation is that patients with clinical evidence of Lyme disease be screened with Immunofluorescence Assay (IFA) or Enzyme Immunoassay (EIA) and should those test results be positive or borderline then confirm findings with a Western Blot.
A patient has a reactive RPR at a titer of 1:128 and a reactive TP-PA. What do these results indicate?
True-Positive diagnosis if Syphilis
A patient has a reactive RPR at a titer of 1:128 and a reactive MHA-TP. What does this indicate for the patient?A) True-positive diagnosis of syphilisB) False-positive diagnosis of syphilisC) True-negative ruling out syphilisD) False-negative ruling out syphilis
True-positive diagnosis of syphilis
which test is recommended for testing cerebrospinal fluid for detection of neurosyphilis?
VDRL
false positive serological tests for lyme disease may be caused by all of the following except
a patient in the early stage of the disease
false positive nontreponemal tests for syphilis may occur because of which of the following?
all of the above
a 15 year old girl returned from a camping trip. approximately a week after her return, she discovered a small red area on her leg that had a larger red ring around it. Her physician had her tested for lymes diseas, but the serological test was negative. What is the best explanation for these results?
antibody response is often below the level of detection in early stages
Which of the following is a cause of a biological false-positive in the screening assays for syphilis?A) prozoneB) reagents too coldC) sera dried on cardD) autoimmune disease
autoimmune disease
treponema pallidum and borrelia burgdorferi can be distinguished from each other on the basis of which of the following?
only B burgdorferi can be grown in the laboratory on artificial media
advantages of direct fluorescent antibody testing to T pallidum include all of the following except
careful specimen collection is less important than in dark field testing
select the characteristic associated with borrelia miyamotoi
causes relapsing fevers
which of the following tests is the most specific during the early phase of lyme disease?
detection of B burgdorferi DNA by PCR
a 24 year old man who had just recovered from infectious mononucleosis had evidence of a genital lesion. His RPR test was positive. What should the technologist do next?
do a confirmatory treponemal test
the clinical hallmark of early lyme disease infection is:
erythema migrans
which of the following is a cause of a laboratory-induced false-negative result in the screening tests for syphilis?
excess serum antibody
The RPR and VDRL are similar in which of the following ways? RPR and VDRL are both:A) read macroscopicallyB) flocculation reactionsC) specific assays for syphilisD) antigen detection assays
flocculation reactions
Which of the following is a confirmatory test for syphilis?A) Rapid Plasma ReaginB) fluorescent antibody (FTA)C) VDRLD) All of the above
fluorescent antibody (FTA)
advantages of polymerase chain reaction testing for lyme disease include which of the following?
high spensitivity
which of the following is true of treponemal tests for syphilis?
in large volume testing, they are often used as screening tests
in the fluorescent treponemal antibody absorption (FTA-ABS) test, what is the purpose of absorption with reiter treponemes?
it prevents cross reactivity with antibody to nonpathogenic treponemes
a new technologist is busy one night and has to perform an RPR on a serum sample. He does not calibrate the needle delivering the antigen, and the needle is delivering a larger volume of antigen than it is supposed to. What kind of error can this produce?
laboratory- induced false negative resulting from postzone
an RPR test done on a 19 year old woman as part of a prenatal workup was negative but exhibited a tough appearance. What should the technologist do next?
make serial dilutions and do a titer
borrelia miyamotoi infection
may explain some cases of supposed lyme disease where no rash was found
