Deck 24: Chlamydia, Rickettsia and Similar Organisms

Question 1

What organism causes endemic typhus?

A)Rickettsia typhi
B)R.canada
C)R.rickettsii
D)R.prowazekii

Answer 1

A
Endemic typhus is caused by R.typhi.The arthropod vector is the oriental rat flea and the rat is the reservoir.

Question 2

What organism's unique life cycle contains an elementary body and a reticulate body?

A)Haemophilus
B)Chlamydia
C)Ureaplasma
D)Mycoplasma

Answer 2

B
The unique life cycle of Chlamydia involves two distinct forms: an elementary body (EB), which is infectious, and a reticulate body (RB), which is noninfectious.

Question 3

What organism has been established as a risk factor for Guillain-Barré syndrome?

A)Chlamydophila pneumoniae
B)C.trachomatis
C)C.psittaci
D)C.urealyticum

Answer 3

A
C.pneumoniae is recognized as an important respiratory pathogen.It is known to be the cause of acute respiratory disease, pneumonia, and pharyngitis.It also has been isolated from patients with otitis media with effusion, pneumonia with pleural effusion, and aseptic pharyngitis.Infection with C.pneumoniae has been established as a risk factor for Guillain-Barré syndrome, an immunologically mediated neurologic disease.

Question 4

Guidelines for testing and reporting the results of Chlamydia trachomatis testing on patients include all the following except:

A)testing specifically using profiles.
B)reporting which tests were and were not performed.
C)reporting unusual observations.
D)performing a routine culture in addition to all the tests for Chlamydia.

Question 5

What is the most commonly used test technique to detect Chlamydia trachomatis infection?

A)Enzyme immunoassay (EIA)
B)Nucleic acid probes
C)Cell culture
D)Cytologic methods

Question 6

What organism causes epidemic louse-borne typhus?

A)Rickettsia typhi
B)R.canada
C)R.rickettsii
D)R.prowazekii

Question 7

A 4-day-old infant shows symptoms of conjunctivitis.A Giemsa stain of the conjunctival scraping shows perinuclear cytoplasmic inclusions.This organism is most likely:

A)C.trachomatis serovars A, B, Ba, C.
B)C.trachomatis serovars D-K.
C)C.trachomatis serovars L1, L2, L3.
D)C.pneumoniae.

Question 8

Why are antibody detection methods for Chlamydia trachomatis infection severely limited in the knowledge they provide the physician?

A)Because C.trachomatis is an intracellular parasite, the body does not produce antibodies against it.
B)Only IgE antibodies are produced against C.trachomatis.
C)Many people have antibodies from previous infections, and local infections do not cause great increases in antibody levels.
D)All of the above.

Question 9

What method is used to confirm a positive Chlamydia trachomatis enzyme immunoassay (EIA)?

A)Cytologic methods
B)Direct fluorescent antibody (DFA)
C)Cell culture
D)Nucleic acid probes

Question 10

What organism causes Rocky Mountain spotted fever?

A)Rickettsia prowazekii
B)R.typhi
C)R.canada
D)R.rickettsii

Question 11

What testing method is the method of choice for detecting antibodies to Chlamydophila pneumoniae?

A)Direct fluorescent antibody (DFA)
B)Serologic tests
C)Cell culture
D)Enzyme immunoassay (EIA)

Question 12

Infants can contract all the following chlamydial infections when passing through the birth canal except:

A)conjunctivitis.
B)nasopharyngeal infections.
C)pneumonia.
D)endocarditis.

Question 13

What organisms are considered obligate intracellular parasites?

A)Chlamydia
B)Mycoplasma
C)Ureaplasma
D)Haemophilus

Question 14

What disease, caused by Chlamydia trachomatis, is considered a sexually transmitted disease where the organisms enter the lymph nodes near the genital tract, resulting in bubo formation and ultimately rupturing the lymph node?

A)Lymphogranuloma venereum (LGV)
B)Trachoma
C)Pelvic inflammatory disease (PID)
D)Conjunctivitis

Question 15

Chlamydia trachomatis produces all the following conditions in adult women except:

A)pelvic inflammatory disease (PID).
B)salpingitis.
C)bacterial vaginosis.
D)endometritis.

Question 16

All of the following are urogenital infections in men, produced by Chlamydia trachomatis except:

A)epididymitis.
B)orchitis.
C)prostatitis.
D)nongonococcal urethritis (NGU).

Question 17

A young man goes to his physician complaining of a discharge from his penis.The physician collects a slide for Gram stain and a swab for culture and sends them to the laboratory.The Gram stain is prepared and read: greater than 25 wbc/hpf, no bacteria seen.The culture results after 48 hours show no growth.What is the most probable diagnosis and the organism responsible?

A)Urethritis, Streptococcus pneumonia
B)Epididymitis, Moraxella
C)Nongonococcal urethritis, Neisseria meningitidis
D)Nongonococcal urethritis, Chlamydia trachomatis

Question 18

What disease does Chlamydophila psittaci cause in humans?

A)Conjunctivitis
B)Endocarditis
C)Parrot fever
D)Bird flu

Question 19

What has an outer membrane similar to that of many gram-negative bacteria, with the most prominent feature being the major outer membrane protein?

A)Haemophilus
B)Reticulate body
C)Elementary body (EB)
D)Intracellular parasites

Question 20

Chlamydia trachomatis is the infectious agent in all the following conditions in humans except:

A)trachoma.
B)urogenital infections.
C)lymphogranuloma venereum (LGV).
D)pharyngitis.

Question 21

All of the following diseases are associated with Chlamydia trachomatis except:

A)Undulant fever.
B)Urethritis.
C)Conjunctivitis.
D)Lymphogranuloma venereum.

Question 22

Diseases caused by rickettsial organisms are typically transmitted to man by:

A)ingestion of contaminated food.
B)an arthropod vector.
C)animal bites.
D)inhalation of aerosols.

Question 23

What organism causes human monocytic ehrlichiosis and uses the lone star tick (Amblyomma americanum) as its primary vector?

A)Neorickettsia sennetsu
B)Ehrlichia chaffeensis
C)Anaplasma phagocytophilum
D)Leptotrombidium deliensis

Question 24

Fifty years after his release from a concentration camp, a man develop signs and symptoms of typhus.He has no known contacts or source of disease exposure at this time; however, he may have had it in 1945.What is the most likely current diagnosis?

A)Oroya fever
B)Q fever
C)Rocky Mountain spotted fever
D)Brill Zinsser syndrome