Name:………………………………………………………………Group 1

17.04.2007.

1. The main factor responsible for lesions in diphtheria involves:

a) exotoxin

b) endotoxin

c) intracellular growth of bacteria

d) all of the above

2. In treatment of diphtheria it is most important to administer:

a) antitoxin

b) anatoxin

c) antibiotics

d) sulphonamides

3. Anti-diphtheria vaccine contains:

a) anatoxin

b) antitoxin

c) atenuated bacteria

d) inactivated bacteria

4. The main factor responsible for virulence of L.monocytogenes involves:

a) listeriolysin

b) protein A

c) enterotoxin

d) presence of cilia

5. Legionella pneumophila rods can be cultured on:

a) agar medium enriched with yeast extract and cystein

b) medium containing 10% sheep blood

c) Mueller-Hinton medium

d) only in tissue cultures

6. Ziehl-Neelsen technique is used to stain:

a) Mycobacterium avium complex

b) Mycobacterium bovis

c) Mycobacterium tuberculosis

d) all of the above

7. Mycobacterium tuberculosis induces:

a) tuberculosis of intestines

b) pulmonary tuberculosis

c) tuberculosis of bones

d) all of the above

8. Positive tuberculin test depends on:

a) cell mediated immunity against Mycobacterium tuberculosis

b) humoral immunity

c) both types of the immune response

d) none of the above

9. Lövenstein-Jensen medium permits to culture:

a) Mycobacterium leprae

b) Mycobacterium tuberculosis

c) both of the above

d) none of the above

10. Mycobacterium leprae induces:

a) skin tuberculosis

b) leprosy

c) pulmonary tuberculosis

d) intestinal tuberculosis

1. Mycobacterium spp. belong to:

a) rapidly growing bacteria

b) slowly growing bacteria

c) microaerophilic bacteria

d) anaerobic bacteria

2. Diphtheria prevention includes:

a) use of vaccines

b) administration of antibiotics

c) treatment of the carriers

d) all of the above

3. Infection with diphtheria occurs via:

a) respiratory route

b) alimentary route

c) urinary tract

d) venereal route

4. Infections with L.monocytogenes may develop as:

a) gastric ulcers

b) alimentary infections

c) venereal diseases

d) all of the above

5. Listeria monocytogenes are:

a) ciliated G+ rods

b) G+ rods with no cilia

c) ciliated G- rods

d) G- rods with no cilia

6. Development of clinical signs/symptoms of L.pneumophila induced disease is promoted by:

a) generalised immune deficit

b) decreased local immunity in lungs due to, e.g., smoking of cigarettes

c) both of the above

d) none of the above

7. Test with tuberculin establishes diagnosis of infection with:

a) Mycobacterium tuberculosis

b) Mycobacterium leprae

c) Mycobacterium avium

d) all of the above

8. Test with lepromin establishes diagnosis of infection with:

a) Mycobacterium avium

b) Mycobacterium tuberculosis

c) Mycobacterium bovis

d) Mycobacterium leprae

9. Positive niacin test is diagnostic of:

a) Mycobacterium avium

b) Mycobacterium leprae

c) Mycobacterium bovis

d) Mycobacterium tuberculosis

10. In humans, tuberculosis is induced by:

a) Mycobacterium avium

b) Mycobacterium microti

c) Mycobacterium tuberculosis

d) Mycobacterium leprae

1. How is L. pneumophila transmitted?

1. respiratory droplets

2. foodborne

3. aerosols from contaminated air-conditioning

4. human to human transmission

2. Due to cold growth some fairly common animal fecal bacteria potentially contaminate some deli meats and soft cheeses; therefore, renal transplant patients should only have hot deli sandwiches. What is this causative agent of meningitis in transplant patients ?

1. S.pneumoniae

2. L.pneumophila

3. L.monocytogenes

4. N.gonorrhoeae

3. What causative agent is most likely responsible for patient with sore throat with pseudomembrane, “bull neck”, potential respiratory obstruction :

1. C.pseudodiphtheriae

2. H.influenzae

3. L.micdadei

4. C.diphtheriae

4. When comparing pertussis and diphtheria, true statements include which of the following ?

1. both pertussis and diphtheria are caused by bacteria that must adhere to respiratory tract cells

2. diphtheria symtoms are caused by an exotoxin, but no symptoms of pertussis result from an exotoxin

3. the bacteria responsible for diphtheria and pertussis both produce endotoxin

4. pertussis is caused by an intracellular pathogen, but diphtheria is caused by an extracellular pathogen

5. A 2-year-old child was admitted to the hospital with acute meningitis. The gram-positive, short rods, and the mother indicated that the child had received “all” of the meningitis vaccinations. What is the most likely cause of the disease?

a) H.influenzae

b) L.monocytogenes

c) Neisseria meningitides

d) Corynebacterium diphtheriae

6. What is the difference between Diphtheroids and C.diphtheriae ?

1. Morphological properties

2. Biochemical properties

3. Inability to produce exotoxin

4. None of them

7. The Microbiology laboratory has chosen to culture all sputum samples received for Legionellae. Which medium is more likely to recover the organisms ?

1. cysteine - tellurite agar

2. buffered charcoal yeast extract agar

3. brucella agar

4. potato dextrose agar

9. What organism is most likely responsible for bacterial meningitis in neonates:

1. S.aureus

2. L.monocytogenes

3. C.diphtheriae

4. Lactobacillus sp.

10. How must diphtheria be treated?

1. antitoxin, antibiotics

2. toxoid, antibiotics

3. antibiotics

4. none of the above

1. Which of the following genetic mechanisms is responsible for the conversion of non-virulent strains of C. diphtheriae to virulent strains?

1. genetic transformation

2. lysogenic phage conversion

3. conjugation

4. genetic recombination

3. The best treatment for a patient with “Legionnaire's disease” is:

1. penicillin

2. cephalosporins

3. erythromycin

4. vancomycin

5. A 2-week-year old newborn developed meningitis. Short, gram-positive rods were isolated and identified as Listeria organisms. The mother had eaten unpasteurized cheese from Mexico during the pregnancy and recalled having a flulike illness. Listeria monocytogenes causes a variety of diseases, including food poisoning. Which of the following best describes these microorganism?

1. flagella are produced both at room temperature and at 37ºC

2. Listeria are facultative intracellular pathogens

3. Once infected, the immune system cannot destroy Listeria

4. Listeria cannot be cultivated on artificial media

6. The primary virulence mechanism of L.pneumophila is its:

1. potent cytotoxin that inhibits motility of respiratory cilia

2. proteases that inflict damage to host tissue

3. antiphagocytic capsule

4. ability to induce phagocytosis and survive in the phagosome

7. The most important virulence factor of L.monocytogenes is:

1. liseriolysin O

2. exotoxin

3. pyrogenic toxin

4. pertussis toxin

8. When comparing pertussis and diphtheria, true statements include which of the following?

1. both pertussis and diphtheria are caused by bacteria that must adhere to respiratory tract cells

2. diphtheria symtoms are caused by an exotoxin, but no symptoms of pertussis result from an exotoxin

3. the bacteria responsible for diphtheria and pertussis both produce endotoxin

4. pertussis is caused by an intracellular pathogen, but diphtheria is caused by an extracellular pathogen

9. How can diphtheria be prevented?

1. DTaP vaccine

2. antitoxin

3. antibiotics

4. sulphonamides

1. Pneumonia in an older male heavy smoker and drinker. Two of his bar buddies have the same acute onset of pneumonia with severe headache, mental confusion, and diarrhea but no sputum. What is the causative agent is?

1. L.monocytogenes

2. L. pneumophila

3. Enterococcus spp.

4. all of the above

2. C.diphtheriae causes diphtheria disease. C.diphtheriae is best characterized by which of the following statements?

1. it produces at least one protein toxin consisting of two subunits, A and B, that cause severe spasmodic cough, usually in children

2. it requires cysteine for growth

3. it produces a toxin that blocks protein synthesis in an infected cell and carriers a bacteriophage that produces the genetic information for toxin production

4. it secretes an exotoxin that has been called “verotoxin”, infection is mediated by specific attachment to mucosal membrane

3. Among the four presented bacterial species, which one respond to following description: gram-positive rod with β-hemolysis on blood agar and motility, which causes foodborn disease?

1. Corynebacterium diphtheriae

2. Lactobacillus

3. Legionella pneumophila

4. Listeria monocytogenes

4. A major step in the pathogenesis of listeriosis is:

1. the release of hyaluronidase by L.monocytogenes, which contributes to its dissemination from local sites

2. the antiphagocytic activity of the L.monocytogenes capsule

3. the ability of polymorphonuclear leucocytes to phagocytize and destroy L.monocytogenes early in the course of the disease

4. the survival and multiplication of L.monocytogenes within mononuclear phagocytes and host epithelial cells

5. A diagnosis of diphtheria is confirmed by:

1. microscopic appearance of organisms stained with methylene blue

2. isolation of a typical colony on Tinsdale's agar

3. demonstration of toxin production by a suspicious isolate

4. isolation of typical organisms from materials such as blood, showing invasiveness

6. Which statement is true for L.monocytogenes ?

1. limits the concentration of potentially harmful germs in the digestive tract

2. produces an extracellular toxin which lyses membrane-bound vacuoles of epithelial cells and monocytes

3. positively affects the immune response by improving the intestinal microbial balance

4. none of the above

7. Which of the following tests is heterogeneous immunoassay? Its detection system is based on enzymatic activity.

a. Latex agglutination (LA)

b. Enzyme-linked immunosorbent assay (ELISA)

c. Enzyme multiplied immunoassay test (EMIT)

d. Counterimmunoelectrophoresis (CIE)

e. Coagglutination (COA)

8. Which of the following tests is used extensively to detect microbial antigens rapidly (5 min or less)? Inert particles are sensitized with either antigen or antibody.

a. Latex agglutination (LA)

b. Enzyme-linked immunosorbent assay (ELISA)

c. Enzyme multiplied immunoassay test (EMIT)

d. Counterimmunoelectrophoresis (CIE)

e. Coagglutination (COA)

1. The enzyme conjugate in an indirect ELISA is:

a. an anti-antibody

b. an antibody

c. an antigen

d. an anti-antigen

2. Which of the following type of ELISA method is present on the picture:

a. direct test

b. sandwich method

c. capture method

d. competitive test

3. Which of the following type of ELISA method is present on the picture:

a. direct test

b. sandwich method

c. capture method

d. competitive test

4. Which of the following type of ELISA method is present on the picture:

a. direct test

b. sandwich method

c. capture method

d. competitive test

5. Which of the following type of ELISA method is present on the picture:

a. direct test

b. sandwich method

c. capture method

d. competitive test

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