Deck 24: Chlamydia, Rickettsia, and Similar Organisms

Question 1

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

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

Answer 1

D

Question 2

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.

Answer 2

B

Question 3

What organisms are considered obligate intracellular parasites?

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

Answer 3

A

Question 4

What organism causes human monocytic ehrlichiosis (HME) 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 5

What organism causes endemic typhus?

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

Question 6

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 reveals greater than 25 white blood cells/high-power field, 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 pneumoniae
B) Epididymitis, Moraxella
C) Nongonococcal urethritis, Neisseria meningitidis
D) Nongonococcal urethritis, Chlamydia trachomatis

Question 7

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

A) PID
B) salpingitis
C) bacterial vaginosis
D) endometritis

Question 8

An invasive genital disease associated with buboes in the groin describes an infection caused by

A) Rickettsia conorii.
B) Rickettsia rickettsii.
C) Chlamydophila psittaci.
D) Chlamydia trachomatis.

Question 9

What method is used to confirm a positive Chlamydia trachomatis EIA?

A) Cytologic methods
B) Direct fluorescent antibody (DFA)
C) Cell culture
D) NAAT

Question 10

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 11

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 12

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

A) DFA
B) Microimmunofluorescence
C) Complement fixation
D) Latex agglutination

Question 13

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) RB
C) EB
D) Intracellular parasites

Question 14

What organism causes epidemic louseborne typhus?

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

Question 15

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

Question 16

What organism's unique life cycle contains an elementary body (EB) and a reticulate body (RB)?

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

Question 17

What is the preferred technique to rapidly detect Chlamydia trachomatis in clinical specimens?

A) Enzyme immunoassay (EIA)
B) Nucleic acid amplification test (NAAT)
C) Cell culture
D) Cytologic methods

Question 18

What organism causes Rocky Mountain spotted fever?

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

Question 19

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 20

What disease does Chlamydophila psittaci cause in humans?

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

Question 21

What is the name of the test used to detect rickettsial agents?

A) Levy-Jennings
B) Mueller-Hinton
C) Weil-Felix
D) Watson-Crick

Question 22

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

A) undulant fever.
B) urethritis.
C) conjunctivitis.
D) LGV.

Question 23

Diseases caused by rickettsial organisms are typically transmitted to humans by

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

Question 24

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

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