Name:………………………………………..……Group 1

16.11.2007

1. H.influenzae capsule type b consists of:

a) lipopolysaccharides (LPS)

b) polyribose - ribitol phosphate (PRP)

c) outer membrane protein (OMP)

d) lipooligosaccharide (LOS)

2. Which of the following bacteria induce lesions to ciliated epithelial cells:

a) H.influenzae

b) P.aeruginosa

c) B.pertussi

d) S.aureus

3. A patient presented to the eye casualty with a painful eye. Coneal scrappino showed the Gram negative bacilli. What is the most common predisposing factor for this infection?

a) S. aureus

b) P. aeruginosa

c) H. influenzae typ b

d) N. gonorrhoeae

4. Bordetella pertussis, called whooping cough, can best be detected by which of the following procedures?

a) Culture of respiratory secretions in HeLa cells after centrifugation of the inoculated tubes

b) Culture of respiratory secretions on Regan-Lowe agar

c) Direct microscopy of sputum by Gram stain

d) Fluorescent antibody detection of the organism in sputum

5. Which of the following is a preferred third - generation cephalosporin with good activity against childhood meningitis?

a) Ceftazidine

b) Ceftriaxone

c) Penicillin

d) Streptomycin

6. There are variety of unusual bacteria that infect humans. While rare disease caused by these microorganisms is serious and occasionally difficult to identify. Which of the following statements best characterizes Moraxella catarrhalis?

a) A gram-negative, pleomorhic rod that can cause endocarditis

b) A gram-negative rod, fusiform-shaped, that is associated with periodontal disease but may cause sepsis.

c) The causative agent of sinusitis, bronchitis, and pneumonia

d) The causative agent of rat-bite fever

7. The virulence factors N.memingitidis responible for or thought to faciliate adherence to the nospharyngeal mucosa are:

a) fagella and spores

b) exotoxins and enterotoxins

c) pili and IgA 1 protease

d) outer membrane proteins (OMP)

8. Meningococcal vaccins:

a) are prepared from the cell wall of N. menigitidis

b) are serogroup - specific, capsular poysaccharides

c) are particilarly effective in the prevention of disease due to serogroup B

d) rarely prevent dissemination of organisms from the primary site

9. Several days after an unprotected sexual encounter, a healthy 21-years old male develops pain and pus on urination. A Gram stain reveals gram-negative diplococci. Which of the following structures is most responsible for adherence of the offending microbe to the urethral mucosa?

a) capsule

b) fimbriae

c) flagella

d) the F pili

10. Several Neisseria species are a part of the normal flora (commensals) of the human upper respiratory tract. Which of the following statements accurately describes the significance of these bacteria?

a) As a part of the normal flora, Neisseriae provide a natural immunity in local host defense.

b) As a part of the respiratory flora, they are the most common cause of acute bronchitis and pneumonia

c) Commensal bacteria stimulate a cell-mediated immunity (CMI)

d) Normal flora such as nonpathogenic Neisseriae provide effective nonspecific B-cell-mediated humoral immunity.

Name:………………………………………..……Group 2

16.11.2007

1. Etiologic agent of meningitis in infants and children aged 2 months to 5 years:

a) Haemophilus influenzae type b

b) Streptococcus pneumoniae

c) Neisseria meningitidis

d) All of the above

2. Acellular B.pertussis vaccine contains:

a) LPS

b) polysaccharide capsule

c) tracheal cytotoxin

d) FHA, pertactin, pertussis toxoid

3. What is the treatment for pertussis?

a) Vancomycin

b) Penicillin

c) Ceftazidine

d) Erythromycin

4. A hyperemic edema of the larynx and epiglottis that rapidly leads to respiratory obstruction in young children is most likely to be caused by which of the following organisms?

a) Haemophilus hemolyticus

b) H. influenzae

c) K. pneumoniae

d) Neisseria meningitides

5. A sputum sample was brought to the laboratory for analysis. Gram stain revealed the following: rare epithelial cells, 8 to 10 polymorphonuclear leukocytes per high-power field, and pleomorphic gram-negative rods. As a laboratory consultant, which of the following interpretations should you make?

a) The appearance of the sputum is suggestive of H. influenzae

b) The patient has pneumococcal pneumonia

c) The sputum specimen is too contaminated by saliva to be useful

d) There is no evidence of an inflammatory response

6. Gonorrhoea is acquired via:

a) gastrointestinal tract

b) genital tract

c) nasal tract

d) skin

7. N. gonorrhoeae is fastidious pathogen found in sites often contaminated with normal flora. What is the best medium for isolation.

a) Loffler's medium

b) Sheep blood agar

c) Thayer-Martin agar

d) Thisulfate citrate bile salts sucrose medium

8. Primary gonococcal disease:

a) never initiates in the pharynx or rectum

b) occur only as acute male or female urethritis

c) is usually treated with penicillin

d) results in acute inflammatory response characterized by polymorphonuclear leukocytes attracted to the primary site by LOS and host complements.

9. Pelvic inflamatory disease (PID) is caused by:

a) S. aureus

b) S. pyogenes

c) N. meningitidis

d) N. gonorrhoeae

10. N. gonorrhoeae attaches to mucosal cells of the:

a) oral - pharyngel area

b) genitals

c) eyes

d) all of the above

Name:………………………………………..……Group 3

16.11.2007

1. Signs of H.ducreyi (chancroid or soft chancre) include:

a) vomiting

b) stiff neck

c) diarrhea

d) painful, friable ulcer on the genitals

2. How is pertussis prevented?

a) IPV vaccine

b) DTaP vaccine

c) H i b vaccine

d) Hep B vaccine

3. Which of the following is the causative agent of swimmer's ear?

a) H. influenzae

b) P. aeruginosa

c) N. meningitidis

d) H. parainfluenzae

4. A 2-year-old child has a high fever and is irritable. He has a stiff neck. Gram stain smear of spinal fluid reveals gram-negative, small pleomorphic coccobacillary organisms. What is the most appropriate procedure to follow in order to reach an etiological diagnosis?

a) Culture the spinal fluid in chocolate agar and identify the organism by growth factors

b) Culture the spinal fluid in mannitol-salt agar

c) Perform a catalase test of the isolated organism

d) Perform a latex agglutination test to detect the specific antibody in the spinal fluid

5. Bordetella pertussis is a Gram-negative rod that causes severe respiratory disease. Which one of the following statements best characterizes this microorganism?

a) It produces at least one protein toxin consisting of two subunits, A and B, that cause severe spasmodic cough, usually in children

b) It produces a toxin that blocks protein synthesis in an infected cell and carries a lytic bacteriophage that produces the genetic information for toxin production

c) It secretes an erythrogenic toxin that causes the characteristic signs of scarlet fever

d) It secretes an exotoxin that has been called “verotoxin” and “Shiga-like toxin”; infection is mediated by specific attachment to mucosal membranes

6. N. meningitidis causes meningitis in all age groups. Which of the following is a characteristic physiological trait?

a) It causes spontaneous abortion and has tropism for placental tissue due to the presence of the erythritol in allantoic and amniotic fluid.

b) It has a capsule of polyglutamic acid, which is toxic when injected into rabbits.

c) It possesses N-acetylneuraminic acid capsule and adheres to specific tissue by pili found on the bacterial cell surface.

d) It secretes two toxins, A and B, in the large bowel during antibiotic therapy.

7. Most gonococcal strains that produce disseminated disease:

a) are sensitive to killing by normal human serum

b) are A-H-U-auxotrophs

c) do not contain LOS

d) are relatively resistance to penicillin

8. Measures to prevent and control gonorrheae do not include:

a) vaccination

b) the use of condoms

c) treatment of case contact

d) test for cure following therapy

9. Young men (20 years old) with a yellow purulent discharge and dysuria following an incubation period 7 to 14 days. Which of the following is the etiologic agents.

a) H. ducreyi

b) N. gonorrhoeae

c) S. aureus

d) Ps. aeruginosa

10. First day of life, watery exudet from the eyes and hyperemia. What is causative agent:

a) N. gonorrhoeea

b) no infected agent - silver nitrate susceptibility

c) S. epidermidis

d) B. pertussis

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