Deck 21: Spirochete Diseases

Question 1

At which stage of syphilis is the RPR the most sensitive?

A) Primary
B) Secondary
C) Tertiary
D) Latent

Answer 1

Secondary

Question 2

Lyme disease is caused by:

A) Treponema pallidum.
B) Borrelia recurrentis.
C) Leptospira autumnalis.
D) Borrelia burgdorferi.

Answer 2

Borrelia burgdorferi.

Question 3

RPR stands for:

A) reagin plasma reactive.
B) reactive phosphate reagent.
C) rapid plasma reagin.
D) random positive reagin.

Answer 3

rapid plasma reagin.

Question 4

Which of the following is a cause of a laboratory-induced false-negative result in the screening tests for syphilis?

A) Alcohol ingestion prior to blood draw
B) Systemic lupus erythematosus
C) Excess serum antibody
D) Temperature greater than 30°C

Question 5

Patient serum is mixed with gel particles that have been sensitized with Treponema pallidum antigens as well as with unsensitized gel particles in a separate well.Agglutination was observed in the well with sensitized gel particles but not in the well with unsensitized gel particles.What is the interpretation of these results?

A) Positive for anti-T pallidum antibodies
B) Positive for heterophile antibodies
C) Negative for anti-T pallidum antibodies
D) Negative for anticardiolipin antibodies

Question 6

Which of the following is a cause of a biological false-negative result in the nontreponemal tests for syphilis?

A) Rotated too long
B) Rheumatoid arthritis
C) Secondary syphilis
D) Slow rotator speed

Question 7

A patient is suspected of having latent syphilis.Which set of test results for RPR,TP-PA,and CSF-VDRL best confirms this diagnosis?

A) RPR = reactive 1:8; TP-PA = reactive; VDRL = reactive 1:4
B) RPR = nonreactive; TP-PA = reactive; VDRL = nonreactive
C) RPR = nonreactive; TP-PA = nonreactive; VDRL = nonreactive
D) RPR = reactive 1:2; TP-PA = nonreactive; VDRL = nonreactive

Question 8

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) Primary
B) Secondary
C) Latent
D) Tertiary

Question 9

A patient presents with personality changes,altered mental state,and delusions of grandeur.The patient is then diagnosed as having syphilis.The patient is most likely in which stage of syphilis?

A) Primary
B) Secondary
C) Latent
D) Tertiary

Question 10

A 30-year-old man presents to his physician with a painless ulcer on his penis.An RPR performed on the man is reactive 1:128,and the TP-PA test is positive.This man has an infection with:

A) Neisseria gonorrhoeae.
B) Chlamydia trachomatis.
C) Treponema pallidum.
D) Mycoplasma hominis.

Question 11

Treponema pallidum and Borrelia burgdorferi can be distinguished from each other on the basis of which of the following?

A) Only T pallidum has axial filaments.
B) Only B burgdorferi has an outer sheath.
C) Only B burgdorferi can be grown in the laboratory on artificial media.
D) Only T pallidum stimulates IgM production against the membrane proteins.

Question 12

A laboratory test that is used to confirm syphilis and detects specific treponemal antibodies is:

A) VDRL.
B) TP-PA.
C) RPR.
D) monospot.

Question 13

The RPR and VDRL are similar in which of the following ways?

A) Both are read macroscopically.
B) Both are flocculation reactions.
C) Both are specific assays for syphilis.
D) Both are antigen detection assays.

Question 14

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?

A) Primary syphilis
B) Secondary syphilis
C) Tertiary syphilis
D) Latent syphilis

Question 15

The RPR and VDRL tests differ from each other in which of the following ways?

A) Method for reading or visualizing the reaction
B) Specificity of antibody detected
C) Specificity of antigen detected
D) Principle for detecting antigen-antibody complexes

Question 16

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) RPR
B) TP-PA
C) C-reactive protein
D) Monospot test

Question 17

Which of the following is a cause of a biological false-positive in the nontreponemal assays for syphilis?

A) Prozone
B) Reagents too cold
C) Sera dried on card
D) Autoimmune disease

Question 18

A patient has a reactive RPR at a titer of 1:128 and a reactive TP-PA.What do these results indicate?

A) True-positive result; diagnosis of syphilis
B) False-positive result; diagnosis of syphilis
C) True-negative result; ruling out syphilis
D) False-negative result; ruling out syphilis

Question 19

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?

A) Laboratory-induced false negative resulting from postzone
B) Laboratory-induced false positive resulting from postzone
C) Biological false positive
D) Biological false negative

Question 20

A 32-year-old heterosexual male presents to a 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 has had multiple sex partners and does not use condoms.Here are the results of his laboratory tests: RPR = reactive 1:128; TP-PA = reactive; Borrelia burgdorferi IgM = less than 1:8; Rickettsia rickettsii IgM less than 1:8.This patient most likely has:

A) primary syphilis.
B) secondary syphilis.
C) Lyme disease.
D) Rocky Mountain spotted fever.

Question 21

The vectors that transmit Borrelia burgdorferi from natural reservoirs to humans are:

A) deer.
B) mice.
C) ticks.
D) birds.

Question 22

The VDRL test on cerebrospinal fluid for neurosyphilis:

A) is very specific.
B) is very sensitive.
C) does not require the use of a microscope.
D) uses a higher antigen volume than the serum test.

Question 23

Advantages of polymerase chain reaction testing for Lyme disease include which of the following?

A) High sensitivity
B) High specificity
C) Ease of sample collection and preparation
D) All of the above

Question 24

Tests for specific treponemal antibody include which of the following?

A) VDRL
B) RPR
C) FTA-ABS
D) All of the above

Question 25

Which statement about late manifestations of Lyme disease is true?

A) Treatment cannot reverse complications.
B) Both central and peripheral nervous systems may be affected.
C) Cardiac or neurological damage occurs in all cases.
D) Arthritis appears only in elderly patients.

Question 26

The antibody known as reagin is:

A) only present in the disease syphilis.
B) tested for using charcoal sensitized with cardiolipin.
C) found in all patients with primary syphilis.
D) antibody directed against IgG.

Question 27

The antibody called reagin that is found in syphilis:

A) reacts with cardiolipin.
B) is specific for treponemal antigen.
C) appears in all patients within 7 days after exposure to syphilis.
D) is detected by the FTA-ABS test.

Question 28

The clinical hallmark of early Lyme disease infection is:

A) a chancre.
B) erythema migrans.
C) chronic fatigue.
D) a gumma.

Question 29

Syphilis is spread by:

A) rodent vectors.
B) insect vectors.
C) sexual transmission.
D) aerosolized respiratory droplets.

Question 30

What type of test identifies the presence of the reagin antibody that forms against cardiolipin?

A) Treponemal test
B) Nontreponemal test
C) Fluorescent antibody testing
D) Dark-field microscopy

Question 31

Which statement regarding laboratory diagnosis of Borrelia miyamotoi infection is true?

A) Well-established ELISA kits for B miyamotoi antibody that have been approved by the Food and Drug Administration are available.
B) The organism is routinely cultured from blood.
C) Antibody tests are not subject to cross-reactivity with Lyme antibody tests.
D) Polymerase chain reaction may become a valuable diagnostic tool.

Question 32

The Centers for Disease Control and Prevention recommends which two-tiered testing procedure for Lyme disease?

A) Screening by IFA or EIA with positive or borderline result followed by Western blot for confirmation
B) Screening by IFA followed by EIA for confirmation
C) Screening by Western blot followed by PCR for confirmation
D) Screening by EIA followed by PCR for confirmation

Question 33

In areas endemic for Lyme disease:

A) residents (especially children) should be screened by EIA.
B) EIA screening is effective only for adults.
C) the only acceptable screening method is IFA.
D) no one should be screened unless they exhibit clinical signs and symptoms.

Question 34

Laboratory results for 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 syphilis
B) Secondary syphilis
C) Tertiary syphilis
D) Another disease, such as mononucleosis

Question 35

Select the characteristic associated with Borrelia miyamotoi.

A) Usually causes a ring-shaped rash
B) Does not induce antibodies in patients that cross-react in Lyme disease assays
C) Causes relapsing fevers
D) Can be easily cultured in diagnostic procedures

Question 36

Using the reverse algorithm method for syphilis diagnosis,a positive initial test and a negative follow-up test could be interpreted as:

A) a false negative in the treponemal test.
B) a false positive in the nontreponemal test.
C) past syphilis infection with subsequent decline in nontreponemal antibody titers.
D) current syphilis, likely in the secondary stage.