Lesson
Rickettsia. Biological properties. Laboratory diagnostics of rickettsiosis. Serological diagnostics of the epidemic and endemic (murine) typhus, Q-fever.
1. Rocky Mountain Spotted Fever is caused by...
a. *rickettsia rickettsia
b. rickettsia prowazekii
c. coxiella burnetii
d. rickettsia typhi
2. Epidemic typhus is caused by(louse borne)
a. rickettsia typhi
b. salmonella typhi
c.* rickettsia prowazekii
d. shigella sp.
3. Each of the following statements concerningneisseriae is correct EXCEPT:
- *Gram-positive bacilli that are obligate intracellular parasites of eukaryotic cells
- Rickettsiaceae genus consists of two antigenically defined groups: spotted fever group and typhus group
- Bacteria found in ticks, lice, fleas, mites, chiggers, and mammals.
- These zoonotic pathogens cause infections that disseminate in the blood to many organs.
4. Determine the INCORRECT route of transmission for Rickettsia-infection:
- Fecal – oral route by ingestion
- Sexual intercourse
- Parenteral
- *By the bite of infected ticks or mites or by the feces of infected lice or fleas
Lesson
Pathogenic cocci. Staphylococci and streptococci. Morphology and biological properties. Laboratory diagnostics of suppurative and non-suppurative lesions caused by them.
1. Yourpatient has subacute bacterial endocarditis caused by a member of the viridans group ofstreptococci. Which one of the following sites is MOST likely to be the source of the organism?
(A)Skin
(B)Colon
(C)*Oropharynx
(D)Urethra
2. A culture of skin lesions from a patient with pyoderma (impetigo) shows numerous colonies surrounded by a zone of beta hemolysis on a blood agar plate. A Gram-stained smear shows gram-positive cocci. If you found the catalase test to be negative, which one of the following organisms would you MOST probably have isolated?
(A)Streptococcus pyogenes
(B)Staphylococcus aureus
(C)*Staphylococcus epidermidis
(D)Streptococcus pneumoniae
3. The coagulase test, in which the bacteria cause plasma to clot, is used to distinguish
(A)Streptococcus pyogenes from Enterococcus faecalis
(B)Streptococcus pyogenes from Staphylococcus aureus
(C)*Staphylococcus aureus from Staphylococcus epidermidis
(D)Staphylococcus epidermidis from Neisseria meningitides
4. Which one of the following is considered a virulence factor for Staphylococcus aureus?
(A)A heat-labile toxin that inhibits glycine release at the internuncial neuron
(B)An oxygen-labile hemolysin
(C)Resistance to novobiocin
(D)*Protein A that binds to the Fc portion of IgG
5. The MOST important contribution of the capsule of Streptococcus pneumoniae to virulence is
(A)To prevent dehydration of the organisms on mucosal surfaces
(B)*To retard phagocytosis by polymorphonuclear leukocytes
(C)To inhibit polymorphonuclear leukocyte chemo taxis
(D)To accelerate tissue invasion by its collage-nase-like activity
6. The MOST important way the host circumvents the function of the pneumococcal polysaccharide capsule is via
(A)T lymphocytes sensitized to polysaccharide antigens
(B)Polysaccharide-degrading enzymes
(C)*Anticapsular antibody
(D)Activated macrophages
7. Which one of the following is NOT a characteristic of the staphylococcus associated with toxic shock syndrome?
(A)Elaboration of enterotoxin F
(B)Coagulase production
(C)Appearance of the organism in grapelike clusters on Gram-stained smear
(D)*Catalase-negative reaction
8. Which one of the following is NOT an important characteristic of Streptococcus pyogenes?
(A)*Protein A
(B)M protein
(C)Beta-hemolysin
(D)Polysaccharide group-specific substance
9. Of the organisms listed below, which one is the MOST frequent bacterial cause of pharyngitis?
(A)Staphylococcus aureus
(B)Streptococcus pneumoniae
(C)*Streptococcus pyogenes
(D)Neisseria meningitides
10. Over 50 children at an elementary school became violently ill several hours after eating lunch. All of the affected children ate sweet rolls. They developed severe nausea and vomiting, and some additionally developed abdominal cramps and non-bloody diarrhea. All of the students felt much better by the following morning. Gram’s stain of a smear taken from the presumed source of the food poisoning shows abundant gram-positive cocci in grape-like clusters. Which of the following is the most likely causative agent?
(A)Bacillus cereus
(B)Escherichia coli
(C)*Staphylococcus aureus
(D)Streptococcus pneumoniae
(E)Streptococcus pyogenes
11. A 32-year-old female presents with high fever (390C), shortness of breath and cough productive of pink sputum. She reports that she was well the previous night but awoke with a shaking chill which lasted 20 minutes. A gram stain of this patient’s sputum has demonstrated lancet-shaped gram-positive diplococci, surrounded by capsule. The most likely causative agent is
(A)Staphylococcus aureus
(B)Streptococcus pyogenes
(C)*Streptococcus pneumoniae
(D)Klebsiella pneumoniae
(E)Yersinia pestis
12. Laboratory assistant isolated from pus spherical bacteria arranged in grape-like clusters in the smear. What group do these microorganisms belong to?
A – micrococci; B – streptococci;
C- *staphylococci;D- sarcina;
E- tetracocci;F- diplococci
13. Laboratory assistant isolated from nasopharyngeal mucus spherical bacteria arranged in chains in the smear. What group do these microorganisms belong to?
A – micrococci; B – *streptococci;
C- staphylococci;D- sarcina;
E- tetracocci;F- diplococci
14. Some bacteria can cause generalized infection due to ability to split host tissue and spread from the site of entry. Choose from the list invasion factors of pathogenic cocci:
(A)Endotoxins
(B)*Virulent enzymes
(C)Adhesins
(D)Exotoxins
(E)Antiphagocytic factors
15. Which virulent factor of pathogenic cocci from following capable of splitting connective tissue of a host?
(A)Plasmocoagulase
(B)*Hyaluronidase
(C)IgA protease
(D)Fibrinolysine
(E)Hemolysine
16. Which medium should be used to isolate and distinguish streptococci with hemolytic properties?
(A)Meat-peptone gelatin
(B)*Blood agar
(C)Hiss media
(D)Meat-peptone broth
(E)Serum agar
17. Which nutrient medium is the most convenient to isolate pure culture staphylococci from the clinical sample?
(A)Semisolid medium
(B)*Solid medium
(C)Liquid medium
(D)Minimal medium
The bank of Krok-1 tests
1.Furuncle pus smear showed spherical microbes arranged in grape-like clusters. Name these microorganisms.
A.*Staphilococci.
B.Diplococci.
C.Micrococci.
D.Streptococci.
E.Tetracocci.
2.A child with the diagnosis of staphylococcal sepsis was admitted to a hospital. What nutrient medium should be used for patient's blood inoculation to isolate the causative agent of this disease?
A.Ploskirev's medium.
B.Meat peptone broth.
C.*Glucose peptone broth.
D.Buchin's medium.
E. Yolk-salt agar.
3.Feces of a child with enteritis are resuspended in isotonic solution of sodium chloride, and a suspension drop is applied onto selective medium: 10 % milk-salt or yolk-salt agar. What microorganisms are supposed to be isolated?
A.E. coli.
B.*Staphylococci.
C.Streptococci.
D.Klebsiella.
E. Enterococci.
4.A 55-year-old patient is hospitalized to a surgical department with suspicion of sepsis. Choose the specimen which should be obtained for examination.
A.Liquor.
B.*Blood.
C.Urine.
D.Pus.
E. Lymph node punctate.
5.Microbiology examinations are carried out in the neonatal department of a maternity hospital because of the suspicion of a hospital infection. S. aureus from several children and some things was isolated. What properties of isolated cultures should be examined to determine the source of infection?
A.Biochemical activity.
B.Chrornogenesis.
C.Antigenic structure.
D.*Phage type.
E.Antibiotic sensitivity.
6.Cases of suppurative postoperative complications caused by staphylococcus have increased in a surgical unit. Which test should be used to determine the source of infection?
A.Drugs susceptibility test.
B.Serotyping test.
C.Aggression enzymes determination.
D.Toxin production.
E. *Phage typing.
7.Cholecystic infection was caused by microorganisms of spherical oblong form situated in pairs or short chains. On the basis of biological properties the bacteria were referred to group D streptococci. What is their name?
A.β-hemolytic streptococci.
B.α-hemolytic streptococci.
C.Pyogenic streptococci.
D.*Enterococci.
E. Pneumococci.
8.Gram-positive diplococci were revealed during the examination of a patient's sputum. Which microorganism is the most likely to cause the disease?
A.Legionella pneumophila.
B.Neisseria meningitidis.
C.Klebsiella pneumoniae.
D.Mycoplasma pneumoniae.
E.*Streptococcus pneumoniae.
9.Microscopy of the sputum of a patient with croupous pneumonia revealed numerous Gram-positive lanceolate diplococci surrounded by a capsule. Name the most likely causative agent.
A.Chlamidia pneumoniae.
B.Klebsiella pneumoniae.
C.*Streptococcus pneumoniae.
D.Staphylococcus aureus.
E.Escherichia coli.
10.A 12-year-old boy after angina has rheumatic damage of heart. Every successive streptococcal infection worsens the condition of the patient. What preparation is expedient to use for the prevention of complications?
A.Streptococcic toxoid.
B.*Benzylpenicillin sodium salt.
C.Streptococcic bacteriophage.
D.Donor γ-globulin.
E.Autovaccine.
11.A doctor has suspected scarlet fever of a 2-year-old child with catarrh and skin rash. A small quantity of serum against streptococci erythrogenic toxin has been injected intracutaneously. In the place of injection the rash disappeared. What do reaction results indicate?
A.The whole doze of serum can be injected intravenously.
B.The child is hypersensitive to erythrogenic toxin.
C.The disease has been caused by a nonhemolytic streptococcus.
D.*The clinical diagnosis has proved to be true.
E. Immune system of the child is considerably impaired.
Lesson
Pathogenic Gram-negative cocci. Gonococci and meningococci. Biological characteristics and laboratory diagnostics of diseases.
1. Laboratory assistant isolated from spinal fluid samples Neisseria meningitidis (oval cocci arranged in pairs with adjacent sides concave in the smear). What morphological group do these microorganisms belong to?
A – micrococci; B – streptococci;
C- staphylococci;D- sarcina;
E- tetracocci;F- *diplococci
2. A 19-year-old male presents with dribble and painful urination (strangury), purulent discharge from urethra and subfebrile temperature. Two days ago he had sexual intercourse with his girlfriend without condom. Venereologist took discharge for microscopy. Which microscopic picture from following confirms diagnosis “gonorrhea”?
- Gram-negative rods and leucocytes in the smear
- Gram-positive cocci located within leucocytes and outside
- *Gram-negative bean-shaped diplococci located free and within leucocytes
- Spiral gram-negative bacteria
- Gram-negative ovoid small rod located into epithelial cells
3. Which one of the following is NOT an important characteristic of either Neisseria gonorrhoeaeor Neisseria meningitidis?
- *Polysaccharide capsule
- gA protease
- M protein
- Pili
4. Which nutrient medium is the most convenient to isolate pure culture Neisseria meningitidis from the clinical sample?
- Meat-peptone agar
- McConcy agar
- Hiss media
- Meat-peptone broth
- *Serum agar
5. Laboratory assistant isolated from cervical samples Neisseria gonorrhoeae(oval cocci arranged in pairs with adjacent sides concave in the smear). What morphological group do these microorganisms belong to?
A – micrococci; B – streptococci;
C- staphylococci;D- sarcina;
E- tetracocci;F- *diplococci
6. Which nutrient medium is the most convenient to isolate pure culture Neisseria gonorrhoeae from the clinical sample?
- Meat-peptone agar
- McConcy agar
- Hiss media
- Meat-peptone broth
- *Serum or ascitic agar
7.Each of the following statements concerningneisseriae is correct EXCEPT:
(A)They are gram-negative diplococci
(B)They produce IgA protease as a virulence factor
(C)They are oxidase-positive
(D)*They grow best under anaerobic conditions
8. Each of the following statements concerningNeisseria meningitidis is correct EXCEPT:
(A)It is an oxidase-positive, gram-negative diplococcus
(B)It contains endotoxin in its cell wall
(C)*It produces an exotoxin that stimulates adenylate cyclase
(D)It has a polysaccharide capsule that is antiphagocytic
9. A 19-year-old male presents with dribble and painful urination (strangury), purulent discharge from urethra and subfebrile temperature. Two days ago he had sexual intercourse with his girlfriend without condom. Venereologist took discharge for microscopy. Which microscopic picture from following confirms diagnosis “gonorrhea”?
- Gram-negative rods and leucocytes in the smear
- Gram-positive cocci located within leucocytes and outside
- *Gram-negative bean-shaped diplococci located free and within leucocytes
- Spiral gram-negative bacteria
- Gram-negative ovoid small rod located into epithelial cells
The bank of Krok-1 tests
1.Pure culture of cocci-like microorganisms of urethral discharge was isolated from a patient with chronic urethritis. The culture fermented only glucose to acid in the standard Hiss' medium. Name the species of these microorganisms.
A.*Neisseria gonorrheae.
B.Neisseria meningitidis.
C.Staphylococcus aureus.
D.Streptococcus pyogenes.
E.Enterococcus faecalis.
2.Bacteriological examination of pus urethral discharge revealed Gram-negative bacteria of coffee beans shape, which fermented glucose to acid and were found in leukocytes. To what disease causative agents can they be referred?
A.Syphilis.
B.*Gonorrhea.
C.Venereal lymphogranulomatosis.
D.Soft chancre.
E. Leptospirosis.
3.Pus from urethra was inoculated onto special nutrient medium. Tender bluish colonies grew. Microscopical examination revealed Gram-negative bean-shaped diplococci. What disease do they cause?
A.Syphilis.
B.Chlamidiosis.
C.*Gonorrhea.
D.Tularemia.
E.Myeloidosis.
4.An ophthalmologist has suspected blennorrhea (gonococcal conjunctivitis) of a sick child with purulent keratoconjunctivitis. What methods of laboratory diagnostics should be used for the confirmation of the diagnosis?
A.Microscopic and serologic.
B.Serologic and allergic.
C.Biological and phage typing.
D.Biological and allergic.
E.*Microscopic and bacteriological.
5.During bacterioscopic examination of the purulent discharge from the uterus there were revealed Gram-negative bean-like diplococci situated in leukocytes and out of them. Which microorganism is the causative agent of the purulent inflammation of the uterus?
A.Chlamidia trachomatis.
B.*Neisseria gonorrhoeae.
C.Haemophilus vaginalis.
D.Trichomonas vaginalis.
E. Calymmatobacterium granulo-matis.
6.A sick woman has gonorrhea diagnosed on the basis of clinical symptoms. Which method is the most rational for confirmation of the diagnosis?
A.Precipitation test.
B.Infection of laboratory animals.
C.Test with bacteriophage.
D.Hemagglutination test.
E.*Microscopy of pathological material.
7.Urethral purulent discharge is inoculated onto special nutrient medium. There have grown tender bluish colonies. Microscopy has shown Gram-negative bean-shaped diplococci. What disease do they cause?
A.Chlamidiosis.
B.*Gonorrhea.
C.Syphilis.
D.Tularemia.
E.Toxoplasmosis.
8.A bacteriologist using a bacterioscopic test of nasopharynx mucus hasrevealed Gram-negative cocci that resemble coffee beans and are located in pairs or tetrads. Which microorganism was isolated by the bacteriologist?
A.Acinetobacter calcoaceticus.
B.Hemophilus ifluenzae.
C.Streptococcus pneumoniae.
D.Moraxella lacunata.
E. *Neisseria meningitidis.
9.A doctor has diagnosed meningococcal nasopharyngitis of a child with nasopharyngitis. What method of laboratory diagnostics is the most rational for diagnosis confirmation?
A.Serologic.
B.Biological.
C.*Bacteriological.
D.Microscopic.
E.Allergic.
10.From a child with cerebrospinal meningitis there was obtained muddy spinal fluid with numerous leukocytes. Which test should be used for express-diagnostics of the disease?
A. Complement fixation test.
B.Agglutination.
C.*Immunofluorescence test.
D.Hemagglutination.
E.Neutralization.
11.In a kindergarten children and personnel were examined with the purpose of detecting meningococcal carriers. What method of microbiological research should be used?
A.Allergic.
B.*Bacteriological.
C.Bacterioscopic.
D.Biological.
E.Serologic.
Lesson
Enterobacteria. Biological characteristics and classification of family. Characteristics of genera Escherichia, Shigella. Pathogenesis, laboratory diagnostics of coli-enteritis and bacterial dysentery.
1. Within a two-day period, a pediatrician in a rural community sees sixteen children between the ages of 2 and 6 with gastroenteritis. The illness began with a fever and abdominal pain. The diarrhea was initially watery, but in some patients, subsequently became mucoid and bloody. Three days before the onset of illness, all of the children had attended a picnic at a city park where they played in a wading pool later found to have an inadequate level of chlorination. Feces cultures performed on these children showed a nonmotile Gram negative rod that did not split lactose. Which of the following organisms is the most likely cause of the illness?
- Enterohemorrhagic E.coli
- Vibrio cholerae
- *Shigella flexneri
- Salmonella enteritidis
- Yersinia enterocolitica
2. Five days after eating rare hamburgers at a cookout, a 46-year old man presents to his primary care physician with abdominal pains, nausea, and diarrhea. Stool culture grows translucent colonies of motile gram-negative bacteria on MacConkey agar which fermented glucose, maltose and mannitol with acid and gas formation. Which of the following organisms is the most likely cause of the illness?
- *Enteropathogenic E.coli
- Shigella sonnae
- Salmonella enteritidis
- Salmonella typhi
- Proteus vulgaris
3. The pathogenesis of which one of the following organisms is MOST likely to involve invasion of the intestinal mucosa?
(A)Vibrio cholerae
(B)*Shigella sonnei
(C)Enterotoxigenic Escherichia coli
(D)Clostridium botulinum
4. Five hours after eating fried rice at a restaurant, a 24-year-old woman and her husband both developed nausea, vomiting, and diarrhea. Which one of the following organisms is the MOST likely to be involved?
(A)Clostridium perfringens
(B)*Enterotoxigenic Escherichia coli
(C)Bacillus cereus
(D)Salmonella typhi
5. Which medium should be used to isolate and distinguish bacteria based on their ability to split lactose?
a)Meat-peptone agar
b)Meat-peptone broth
c)Blood agar
d)Serum agar
e)*Endo agar or Ploskirev one
The bank of Krok-1 tests
1.A 7-year-old boy has been diagnosed a cholera-like disease (vomiting,profuse diarrhea). The feces of the patient were inoculated onto Endo medium, and homotypic crimson colonies with metallic sheen have grown. Which microorganism is the most likely to be the causative agent of the disease?
A.Shigella sonnei.
B.Salmonella enteritidis.
C.Yersinia enterocolitica.
D.*Escherichia coli, enterotoxigenic type.
E. Vibrio holera.
2.A patient complained of nausea, liquid blood-streaked stool with mucus, fever, general weakness. He was hospitalized to the infectious department of a hospital. A doctor suspected shigellosis. What method of laboratory diagnostics should be administered to confirm this diagnosis?
A.*Bacteriological.
B.Serologic.
C.Mycological.
D.Microscopic.
E.Test on laboratory animals.
3.Pure culture of bacteria isolated from a patient with symptoms of colitis was identified as Shigella genus according to morphological, cultural, and biochemical properties. Which test should be used for serological identification of this culture?
A.Inhibition of hemagglutination.
B.Complement fixation test.
C.Indirect hemagglutination.
D.Precipitation.
E.*Agglutination with diagnostic serums.
4.Stool culture revealed S. zonnei. What additional researches should be carried out to determine the source of infection?
A.Drugs susceptibility test.