Deck 28: Clinical Microbiology and Epidemiology

Question 1

A person who begins to exhibit symptoms of bronchitis and bacterial pneumonia after recovering from the flu would be exhibiting:

A) drug resistance
B) antiviral susceptibility
C) underlying immunodeficiency
D) biological meltdown
E) disease sequelae

Answer 1

E

Question 2

Of the following body sites, which could contain microbes in a healthy individual?

A) blood
B) urine
C) cerebrospinal fluid
D) nasopharynx
E) bladder

Answer 2

D

Question 3

Which of the following genera of bacteria would NOT change the color of N,N,N',N'-tetramethyl-p-phenylenediamine to purple/black upon exposure?

A) Salmonella
B) Brucella
C) Pseudomonas
D) Bordetella
E) Campylobacter

Answer 3

A

Question 4

The Lancefield groupings are for __________ bacteria and based on __________.

A) Streptococcus; carbohydrate peptidoglycans
B) Escherichia; lipopolysaccharides
C) Staphylococcus; peptidoglycan amino acids
D) Neisseria; hopanoids
E) Pseudomonas; optochin sensitivity

Question 5

Low glucose and high protein levels found in the cerebrospinal fluid of a hospitalized patient most likely point to what kind of infection?

A) viral infection
B) bacterial infection
C) protist infection
D) prion infection
E) any of the above

Question 6

The cause of the infection that a patient is suffering from is best known as the:

A) clinical agent
B) etiological agent
C) pathogenic culprit
D) epidemiological agent
E) antibiotic menace

Question 7

Penicillinase-producing Neisseria gonorrhoeae (PPNG) experienced a significant increase in the United States during the 1970s because of the:

A) start of the HIV epidemic and IV drug use
B) feminist movement and increased sexual activity
C) overuse of antibiotics during and after the Vietnam War
D) doctors overprescribing quinolones for malaria
E) concurrent swine flu epidemic in the mid-1970s

Question 8

Collection of a sample from a patient suspected to have malaria would be performed by:

A) blood draw
B) sputum expectorate
C) tissue needle aspirate
D) lumbar puncture
E) clean-catch sampling

Question 9

A bacterial diagnosis of Mycobacterium avium in a sputum sample from an AIDS patient would be best determined by which method?

A) blood agar culture
B) acid-fast (Ziehl-Neelsen) staining
C) MacConkey agar culture
D) Gram staining
E) bacitracin susceptibility

Question 10

A Gram-negative diplococcus result on laboratory testing would rule out all of the following bacteria EXCEPT:

A) Neisseria gonorrhoeae
B) Listeria monocytogenes
C) Staphylococcus epidermidis
D) Haemophilus influenzae
E) Escherichia coli

Question 11

Collection of specimen samples from places on or in the body that contain normal flora usually requires:

A) initial plating on nonselective media
B) direct Gram staining
C) initial plating on selective media
D) direct PCR identification
E) immunofluorescent staining

Question 12

Catalase-positive organisms such as __________ produce __________ as end products when exposed to hydrogen peroxide.

A) Streptomyces; KCl and CO₂
B) Streptococcus; H₂O₂ and H₂O
C) Lactobacillales; CO₂ and O₂
D) Stachybotrys; HOCl and H₂O
E) Staphylococcus; H₂O and O₂

Question 13

An abscess caused by the anaerobic species Clostridium perfringens would best be collected and transported by:

A) aspiration into an oxygen-filled tube
B) swabbed onto blood agar media
C) aspiration into a nitrogen-filled tube
D) draining with a catheter
E) draining into a syringe

Question 14

A person exhibiting glomerular nephritis and rheumatic fever must have had what type of previous infection?

A) Shigella sonnei
B) Escherichia coli
C) Streptococcus pyogenes
D) Treponema pallidum
E) Mycobacterium tuberculosis

Question 15

Chocolate agar is considered __________ in comparison to blood agar.

A) more nutrient-rich (capable of growing a greater variety of bacteria)
B) less nutrient-rich (capable of growing fewer variety of bacteria)
C) equally nutrient-rich (since they both contain red blood cells)
D) a chemically defined media (whereas blood agar is not)
E) better for determining hemolytic bacterial reactions

Question 16

Catheterization would be an appropriate method of microbial collection for:

A) Streptococcus pneumoniae-lung infection
B) Escherichia coli-UTI infection
C) Shigella dysenteriae-GI infection
D) Propionibacterium acnes-skin infection
E) Helicobacter pylori-stomach infection

Question 17

Hektoen agar will grow all of the following microorganisms EXCEPT:

A) Klebsiella pneumoniae
B) Escherichia coli
C) Salmonella enteritidis
D) Shigella sonnei
E) Streptococcus pneumoniae

Question 18

Laboratory analysis of a patient suspected to have bacterial meningitis would be performed with which type of sample?

A) urine sample
B) blood draw
C) throat swab
D) sputum sampling
E) lumbar puncture

Question 19

Haemophilius influenzae requires __________ and __________ for confirmatory growth of an organism in vitro.

A) catalase; oxidase (N disk)
B) Eosin-Methylene Blue (EMB) agar; MacConkey agar
C) citrate; bile salts
D) hemin (X factor); NAD (V factor)
E) phenylalanine; ortho-Nitrophenyl- $\beta$ -galactoside (ONPG)

Question 20

Shigella sonnei is the cause of an infection commonly seen in infant day-care facilities due to:

A) a high prevalence of the microbe in young children
B) its ability to contaminate and grow on plastic toys
C) its inherent antimicrobial nature (it is bleach and cleaning-product resistant)
D) diaper changes and hands not being properly washed
E) Gram-positive cell wall structure making the bacteria environmentally resistant

Question 21

Point-of-care diagnostics are advantageous for all of the following reasons EXCEPT:

A) culturing is not required
B) therapy can begin sooner
C) patient compliance is improved
D) antibiotics can be prescribed more effectively
E) lower risk of spreading infection

Question 22

Bordetella pertussis is classified as a biosafety risk group II organism. What does this mean?

A) little to no pathogenic potential and standard sterile techniques are sufficient
B) pathogenic potential but generally not via respiratory transmission
C) pathogenic potential and respiratory transmission possible
D) pathogenic potential and containment in pressurized labs
E) extremely dangerous pathogens and rigorous containment in pressurized suits and labs

Question 23

PCR-based detection of a person thought to have HIV would require all of the following EXCEPT:

A) primers specific for HIV genes
B) thermocycler
C) HIV agar media
D) gel electrophoresis
E) HIV genome isolation/extraction

Question 24

In real-time quantitative PCR, light emission will result or will become visible in a person who has a hepatitis C infection when:

A) primers bind to viral hepatitis RNA
B) probe oligonucleotide is degraded during PCR
C) cDNA copies are formed
D) fragments are run on a gel and radiolabeled
E) Taq polymerase bind to the cDNA

Question 25

Which of the following organisms falls within risk group category II?

A) Ebola virus
B) SARS
C) Mycobacterium tuberculosis
D) Escherichia coli strain K-12
E) Campylobacter jejuni

Question 26

A defining commonality between biosafety risk group II handling techniques and a biosafety IV facility would be the need for:

A) a personal positive-pressure suit
B) an isolation facility
C) a negative-pressurized lab space
D) directional air flow in room
E) the use of aseptic techniques

Question 27

Symptoms of headache, fever, stiff neck, and confusion in combination with mosquito bites can indicate which viral infection?

A) Ebola
B) West Nile
C) influenza
D) rabies
E) HIV

Question 28

Eukaryotic parasites, such as Giardia lamblia, are usually diagnosed by:

A) immunofluorescence
B) PCR
C) RFLP
D) biochemical testing
E) direct microscopy

Question 29

The use of a laminar flow hood when studying the organism Francisella tularensis is an example of:

A) level 0 biological safety
B) level I biological safety
C) level II biological safety
D) level III biological safety
E) level IV biological safety

Question 30

Lowenstein-Jensen agar is used to culture which of the following clinical specimens?

A) all Gram-negative bacteria
B) beta lactase-producing bacteria
C) mycolic acid-containing bacteria
D) all Gram-positive bacteria
E) toxin-producing enteric bacteria

Question 31

A proper course of action for a patient presenting with Ebola would be:

A) quarantine and laboratory determination of Ebola IgG antibodies
B) vaccination and laboratory growth of Ebola in culture
C) course of antibiotics and laboratory determination of Ebola antigen
D) antiviral therapy followed by a course of antibiotics
E) in-home supportive therapy and laboratory PCR detection

Question 32

Most point-of-care diagnostics rely on:

A) immunochromatographic assays
B) Qt-polymerase chain reaction
C) ELISA kits
D) immunofluorescence
E) API platforms

Question 33

A serum antibody ELISA would be looking for which of the following in a person who is presumed to have a necrotizing fasciitis infection?

A) anti-group A streptococcal antibodies
B) antimeningococcal antibodies
C) group A streptococcal-specific antigens
D) enzyme-linked antibody
E) anti-group B streptococcal antibodies

Question 34

A disease geographically spread by the movement of migrating birds is:

A) hantavirus
B) Ebola
C) Lyme
D) West Nile
E) influenza

Question 35

Humans are an incidental (dead-end) host in which clinical disease?

A) West Nile virus
B) Mycobacterium tuberculosis
C) Streptococcus pyogenes
D) Staphylococcus aureas
E) picornavirus

Question 36

A hemolysis reaction (on a blood agar plate) with an unidentified colony that results in a green zone due to oxidized iron in nonlysed red blood cells would be called:

A) beta-hemolytic
B) nonhemolytic
C) gamma-hemolytic
D) alpha-hemolytic
E) epsilon-hemolytic

Question 37

An antigen-capture ELISA could be looking for all of the following in a person who is presumed to have a severe acute lung infection EXCEPT:

A) mycobacterium antigens
B) SARS antigens
C) Haemophilus sp. antigens
D) pneumococcal antigens
E) anti-influenza antibodies

Question 38

Fluorescent antibody staining works well for clinical diagnosis on what types of antigens?

A) ribosomal
B) cytoplasmic
C) nuclear
D) capsular
E) plasmid

Question 39

Direct fluorescent staining of infected tissue samples taken from a patient allows for rapid identification under what circumstances?

A) hard-to-culture organisms
B) protist infections
C) Gram-negative organisms
D) intracellular infections
E) metabolically active organisms

Question 40

Real-time PCR on a clinical sample from a suspected hantavirus patient can determine both:

A) antibodies to hantavirus and viral resistance
B) viral resistance and viral load
C) presence of hantavirus and viral load
D) antibodies to hantavirus and strength of immune response
E) hanta serotype and strength of immune response

Question 41

Molecular screening is now being used to detect individuals with early stages of TB because:

A) skin testing is unreliable and needs refrigeration that many countries may not have
B) vaccination with Bacille Calmette-Guérin does not protect against multidrug resistance
C) many countries do not have disposable needles for skin testing
D) it can detect infection earlier than chest X-ray and sputum sampling
E) it can be used more safely on children with the disease

Question 42

John Snow, the "father of epidemiology," is known for deducing the source of which etiologic agent in the 1854 London outbreak?

A) Shigella dysenterie
B) Vibrio cholerae
C) Haemophilius influenzae
D) Giardia lamblia
E) Yersinia pestis

Question 43

Looking at the laboratory results presented here, what three interpretations can you make?

Question 44

Which of the following is the correct definition of bioweapon?

A) any agent categorized as a biosafety level IV organism
B) any infectious disease spread person to person with a low mortality rate
C) any agent causing widespread psychological trauma, with few casualties
D) any microbial agent or pieces of microbes that can be loaded into bombs
E) any infectious agent or toxin that has a high virulence and/or mortality rate

Question 45

Collaborations necessary to solve and control a human epidemic include:

A) epidemiologists
B) ecologists
C) veterinarians
D) scientists
E) all of the above

Question 46

In determining the bacterial etiology of a patient with an infection, the first laboratory test should be what, and why? What type of testing would then follow?

Question 47

Which infectious disease is on the CDC bioterrorism list due to the general population NOT being vaccinated for this disease since the 1970s?

A) bubonic plague
B) rabies
C) smallpox
D) tuberculosis
E) Machupo virus

Question 48

How does a multiplex PCR reaction differ from a traditional PCR detection method? In addition, describe an example of how multiplex can be used in diagnostics.

Question 49

Describe the general protocol you would use to diagnose a patient with a Salmonella Typhimurium infection (from collection to testing).

Question 50

Bubonic plague is endemic in many countries in Africa and in the former Soviet Union. This means that:

A) plague was once a huge problem and has now evolved to not cause infection
B) plague has been eradicated from these areas
C) large numbers of people are infected in these areas and it is spreading
D) the disease is always present in the population at a low frequency
E) plague is transferred by human-to-human contact

Question 51

Looking at the laboratory results presented here, what three interpretations can you make?

Question 52

In using the PANTHER sensor for quick detection of pathogens, how does the PANTHER detect Francisella tularensis, the causative agent of tularemia?

A) It detects Francisella tularensis antibodies within a given sample.
B) It detects Francisella tularensis DNA using RFLP technology.
C) It detects Francisella tularensis antigen using antigen-specific B cells.
D) It detects Francisella tularensis endotoxins using enzyme-conjugated antibodies.
E) It detects Francisella tularensis antigen using antigen-specific T cells.

Question 53

How can reverse transcriptase PCR (RT-PCR) be used to determine the presence and viral load of HIV infection?

Question 54

The clinical microbiology laboratory just received a sputum (deep-lung) sample that so far has been very slow-growing in nonselective agar, as well as not Gram-stainable. What tests would you suggest next, and why?

Question 55

Which of the following is a reportable, biosafety level III organism that causes low-grade fever, chills, headache, and malaise followed by a dry cough, shortness of breath, and chest heaviness?

A) methicillin-resistant Staphylococcus aureas
B) Plasmodium falciparum
C) West Nile virus
D) Bacillus anthracis
E) Yersinia pestis

Question 56

Tuberculosis has become a reemerging pathogen today in large part due to:

A) increased incidence of HIV infection
B) airline travel reducing geographical distances
C) surge in reservoir animal populations carrying the disease to humans
D) strict compliance with drug regimens
E) concurrent increases in hepatitis C infection

Question 57

How would a serum antibody ELISA work in the detection of Lyme disease?

Question 58

Compare and contrast the dichotomous key approach to bacterial determination with the seven-digit-number approach when using the API strip system.

Question 59

Haemophilus parasuis is a nonpathogenic bacteria frequently found in the upper respiratory tracts of pigs. Pathogenic strains of this bacteria form the etiological agent of Glässer's disease in pigs. Describe how genetic screening could be used to determine if a pig had a pathogenic strain or a commensal strain.

Question 60

Gaëtan Dugas is frequently referred to as the individual who began the spread of HIV within the gay male community in North America in the 1970s. In epidemiology he is known as the:

A) first patient
B) superspreader
C) patient 1
D) index case
E) first data point

Question 61

Compare and contrast the use of point-of-care rapid tests as diagnostic methods in doctors' offices.

Question 62

Compare and contrast the use of the serum antibody ELISA with the antigen-capture ELISA in the detection of Ebola.

Question 63

Describe the chain of command that is followed when a patient sees their doctor and is diagnosed with a reportable disease such as listeriosis.

Question 64

How were Koch's postulates modified in the discovery of Tropheryma whipplei, the causative agent of Whipple's disease?

Question 65

Why are clinical viral diseases more challenging to diagnose than are clinical bacterial diseases?

Question 66

Describe what the One Health Initiative is and the role it played in the 2006 outbreak of food-borne O157:H7 in spinach.

Question 67

How have changes within our human culture caused new diseases to emerge? Explain your answer using a specific example that supports your statements.

Question 68

As a disease detective investigating an outbreak in the cafeteria of your college, what would be some of the first steps you would need to take to begin your investigation, other than laboratory testing?

Question 69

Compare and contrast the epidemiological terms endemic, epidemic, and pandemic. Give an example of each to support your answer.

Question 70

Compare and contrast the handling of rabies (a category III organism) with Lassa fever (a category IV organism).