ELECTIVE III - A MEDICAL MICROBIOLOGY – II

Mrs. T. DHANALAKSHMI

III UG MICROBIOLOGY

.UNIT- I Mycology: superficial infections- Dermatophytes- Microsporum – Trichophyton,Epidermophyton- Madura mycosis- Opportunistic fungal infections- Candida albicans, Aspergillus, Mucor.

Section A

  1. Which of the following fungi is most likely to be found within reticuloendothelial cells.
    a. Histoplasma Capsulatum
    b. Sporothrix Schenckii
    c. Cryptococcus neoformans
    d. Candida albicans
  2. Aspergillosis is recognized in tissue by the presence of
    a. Metachromatic granules
    b. Psuedohyphae
    c. Septate hyphae
    d. Budding cells
  3. Fungi often colonize lesions due to other causes. Which of the following is least likely to be present as colonizer
    a. Candida
    b. Sporothrix
    c. Mucor
    d. Aspergillus
  4. A girl who pricked her finger while pruning some rose bushes develops a local pustule that progresses to an ulcer. Several nodules then develop along the local lymphatic drainage. The most likely agent is
    a. Aspergillus fumigatus
    b. Sporothrix schenckii
    c. Cryptococcus neoformans
    d. Candida albicans
  5. Immunocompromised persons are suffered from several fungal diseases. Which of the following is the least frequently associated
    a. Cryptococcus neoformans
    b. Aspergillus fumigatus
    c. Malassezia furfur
    d. Mucor species
  6. Each of the following statements concerning Cryptococcus neoformans are correct EXCEPT
    a. Its natural habitat is the soil, especially associated with pigeon feces
    b. Budding yeasts are found in the lesions
    c. The initial site of infection is usually the lung
    d. Pathogenesis is related primarily to the production of exotoxin A.
  7. Fungal cells that reproduce by budding are seen in the infected tissues of patients with
    a. Candidiasis, cryptococcosis, and sporotrichosis
    b. Mycetoma, candidiasis and mucormycosis
    c. Tinea corporis, tinea unguium, and tinea versicolor
    d. Sporotrichosis, mycetoma and aspergillosis
  8. Which of the following is not the characteristics of histoplasmosis
    a. Person to person transmission
    b. Specific geographic distribution
    c. Yeasts in tissue
    d. mycelial phase in the soil
  9. Infection with dermatophyte is most often associated with
    a. intravenous drug abuse
    b. inhalation of the organism from contaminated bird feces
    c. adherence of the organism to perspiration moist skin
    d. Fecal-oral transmission
  10. Each of the following statements concerning Candida albicans is correct except
    a. C. albicans is a budding yeast that forms psuedohyphae when it invades tissue
    b. C. albicans causes thrush
    c. C. albicans is transmitted primarily by respiratory aerosol
    d. Impaired cell mediated immunity is an important predisposing factor to disease
  11. Saprophytic fungi
  12. engulf their food in order to break it down
  13. secure their food from dead organic materials
  14. Both
  15. None
  1. The fruiting body of a mushroom is called
  2. Sorocarps b. Basidiocarps c. Ascocarps d. all
  1. The amount of phagocytosis done by the Plasmodium
  2. is greater than by the water mold mycelium
  3. is lesser than by the water mold mycelium
  4. is equal to by the water mold mycelium
  5. None
  6. Water molds belong to which division?
  7. Ascomycota b. Oomycota c. Basidiomycota d. None
  1. ______produce basidiospores
  2. Slime molds b. Dimorphic fungi c. Club fungi d. all
  1. Which fungus causes mycoses of the hair, skin, and nails?
  2. Cryptococcus b. Sporothrix c. Aspergillis d. All dermatophytes
  1. A true fungal pathogen must exhibit what characteristic?
  2. Produce spores b. Produce mycelia c.Thermal dimorphism d. Be distributed worldwide
  3. What are the most prevalent of all fungal infections?
  4. Dermatophytoses b. Histoplasmosis c. Candidiasis d. all
  1. Where do Aspergillus infections usually occur?
  2. Skin b. Nail c. Lungs d. Hair
  3. What is the reservoir for Cryptococcus neoformans?
  4. Pigs b. Human c. Birds d. None

Section B

  1. Briefly discuss pathogenesis of Aspergillosis.
  2. List out the ringworm disease caused by dermatophytes.
  3. Explain about the superficial infection of fungi.

Section C

  1. Comprehensive the pathogenesis, laboratory diagnosis and etiology of Candida albicans
  2. Explain about the Mucor.

UNIT -II

Parasitic diseases- Entamoeba histolytica, Giardia, Taenia solium, Ascaris, Enterobius, Trichuris trichura, Plasmodium vivax, Wuchereria bancrofti

Section A

  1. Which of the following agent is used to prevent Malaria
    a. Mebendazole
    b. Chloroquine
    c. Inactivated vaccine
    d. Zinc table
  2. Each of the following statements concerning Ascaris lumbricoides is correct except:
    a. Ascaris lumbricoides is one of the largest nematode
    b. Ascaris lumbricoides can cause pneumonia
    c. Both dogs and cats are intermediate host of Ascaris lumbricoides
    d. A lumbricoides is transmitted by ingestion of eggs
  3. Each of the following statements concerning kala-azar is correct except:
    a. Kala-azar is caused by leishmania donovani
    b. kala-azar is transmitted by the bite of sandflies
    c. Kala-azar occurs primarily in rural latin America
    d. Kala-azar can be diagnosed by finding amastigotes in bone marrow
  4. Each of the following statements concerning hookworm infection is correct except:
    a. Hookworm infection can cause pneumonia
    b. Hookworm infection is acquired by humans when filariform larvae penetrate the skin
    c. Hookworm infection is caused by Necatar americanus
    d. Hookworm infection can be diagnosed by finding the trophozoite in the stool
  5. Each of the following statements concerning Trichomonas vaginalis is correct except:
    a. T. vaginalis is transmitted sexually
    b. T. vaginalis can be diagnosed by visualizing the trophozoite
    c. T. vaginalis can be treated effectively with metronidazole
    d. T. vaginalis causes bloody diarrhea
  6. Each of the following statements concerning Giardia lamblia is correct except:
    a. G. lamblia has both a trophozoite and cyst stage in its life cycle
    b. G. lamblia is transmitted by the fecal oral route from both human and animal sources
    c. G. lamblia causes hemolytic anemia
    d. G. lamblia can be diagnosed by the string test
  7. Each of the following statements concerning Malaria is correct except
    a. The female anopheles mosquito is the vector
    b. Early infection, sporozoites enter hepatocytes
    c. Release of merozoites from red blood cells cause fever and chills
    d. The principal site of gametocyte formation is the human gastrointestinal tract.
  8. Each of the following parasite is transmitted by mosquitoes except:
    a. Leishmania donovani
    b. Wuchereria bancrofti
    c. Plasmodium vivax
    d. Plasmodium falciparum
  9. Pigs or dogs are the source of human infection by each of the following parasites except:
    a. Echinococcus granulosus
    b. Taenia solium
    c. Ascaris lumbricoides
    d. Trichinella spiralis
  10. In malaria, the form of plasmodia that is transmitted from mosquito to human is the
    a. Sporozoite
    b. Gametocyte
    c. Merozoite
    d. Hypnozoite
  11. All protozoan pathogens have a ……………… phase.
    a. cyst b. sexual c. trophozoite d. blood

12. Which species of Trypanosoma is not a human pathogen?
a.T.cruzi b. T.rangeli c. T.gambiense d. T. Rhidesiense

13. A malarial infected person by blood transfusion does not have ………… in his body.
a. hypnosoite b. trophozoite c. schizont d. gametocyte

14. Rosette in RBC is a specific shape of ………… .
a. P.vivax b. P.falciparum c. P.ovale d. P.malariae

15.. ……………….. enzymes may be destroyed in infected persons by Giardia lamblia.
a. Lipase b. Cytolysin c. Collagenase d. Phosphatase acid

16. What is the pathogenic agent responsible for chiclero ulcer?
a. L.tropica b. L.major c. L.mexicana d. L.braziliensis

17. Which disease is related to Winterbottom’s sign?
a. Sleeping sickness b. Chagas disease c. Kalaazar d. Toxoplasmosis

18. Which of the following items is more important for differentiation between Entamoeba histolytica and Entamoeba dispar?
a. Genomic methods b. Inoculation to specific culture media
c. Electron microscopic examination d. All items are correct

19. What is the result of exflagellation of Plasmodium?
a. Microgamet b. Micrgametocyte
c. Macrogamet d.Macrogametocyte

20. Which one is not zoonosis?
a. Cryptosporidium parvum b. Entamoeba histolytica
c. Balantidium coli d. Toxoplasma gondii

21. Which parasite is related to Oriental sore?
a. L.aethiopica b. L.infantum c. L.tropica d. L.donovani

22. Which parasitic form is related to congenital toxoplasmosis?
a. Tachyzoite b. Trophozoite c. Oocyst d. Tissue cyst

23. Flask shaped ulcers in human intestine are related to ………………….. .
a. Giardiasis b. Cryptosporidiosis c. Cyclosporidiasis d. Amoebiasis

24. Trophozoites of Toxoplasma gondii multiply by ……………….. .
a. Endodyogeny b. Schizogoni c. Binary fission d. Sporogony

25.Which form of leishmania is injected to animal model for lishmanization?
a. Epimastigote b. Trypomastigote c. Promastigote d. Amastigote

Section B

  1. Explain about the Entamoeba histolytica life cycle and pathogensis.
  2. Describe the etiology of Giardia.
  3. Write about the life cycle of Wuchereia bancrofti.
  4. What is the pathogenesis of Trichuris trichura.

Section C

  1. Explain about the Ascaris.
  2. Explain about the Taenia solium life cycle, pathogesis and diagnosis.
  3. Write about the enterobius and plasmodium vivax.

UNIT -III

Etiology and laboratory diagnosis of Urinary tract infection- Meningitis, Diarrhea, Respiratory tract infections.

1. The most frequent bacterial cause to be considered is______.

S. pyogenes. Corynebacterium diphtheriae,

2. What is Diagnosis?
(a) Identification of Diseases (b)Treatment for Diseases (c) Investigation with patients

Ans :a

2.Which one of the following will contaminate the specimen?
(a) Microorganism in Soil (b) Normal micro flora (c) Microorganism in an equipment

Ans :b

3. Whose role should be clearly defined in a written format in medical laboratory?
(a) Clinicians (b) Investigator/Physician(c) Patient

6.Which organism can cause Meningitis?
(a) Staphylococcus spp (b) Neisseria spp(c) None

Ans :b

7. Which of the following bacteria is not associated with Urinary Tract Infections?
(a) E.coli (b) Shigella sp (c) Lactobacilli sp

Ans :c

8. Which is the most specimen/sample collected for Streptococcal infection?
(a) Throat swab (b) Nose swab (3) pus

9. Which of the following represents a molecular method of testing?
(a) Microscopy (b) Selective media (c)DNA probe testing

Ans :c

10. The clinical microbiologist identifies agents and organisms based on which of the following?
(a) Microbiological examination (b) Sero diagnosis (c) Both

Ans :c

11.Which of the following would be used to collect urine specimens?
(a) Clean catheter (b) Clean beaker (c)None of the above

Ans :a

12. Which is the most common specimen collected in suspected cases of lower respiratory infections?

(a) Saliva (b) Sputum (c) Throat swab

Ans :b

13.Each of the following agents is a recognized cause of diarrhea except
(a) Clostridium perfringens (b)Enterococcus faecalis (c) Vibrio cholerae (d) Escherichia coli

Ans :b

14. For liquifying Sputum sample _____ has been used.
(a) N acetyl (b) Saline (c) Both (d) None

Ans :a

15.The identification of bacteria by serologic tests is based on the presence of specific antigens. Which of the following bacterial components is least likely to contain useful antigens?
a. Ribosomes
b. Cell wall
c. Capsule
d. Flagella

16 .Each of the following statements concerning the Gram stain is correct except:
a. Escherichia coli stains pink because it has a thin peptidoglycan layer
b. Streptococcus pyogens stains blue because it has a thick peptidoglycan layer
c Mycoplasma pneumoniae is not visible in the Gram’s stain because it does not have a cell wall
d. Mycobacterium tuberculosis stains blue because it has a thick lipid layer

17. An outbreak of sepsis caused by Staphylococcus aureus has occurred in the newborn nursery. You are called upon to investigate. According to your knowledge of the normal flora, what is the most likely source of the organism?
a. Nose
b. Colon
c. Vagina
d. Throat

18. Each of the following organisms is an important cause of urinary tract infections except:
a. Klebsiella pneumoniae
b. Escherichia coli
c. Bacteriodes fragilis
d. Proteus mirabilis

19.A 30 year old woman has non bloody diarrhea for the past 14 hours. Which one of the to following organisms is least likely to cause this illness?
a. Streptococcus pyogens
b. Clostridium difficile
c. Shigella dysenteriae
d. Salmonella enteritidis

20.Each of the following agents is a recognized cause of diarrhea except
a. Clostridium perfringens
b. Vibrio cholerae
c. Enterococcus faecalis
d. Escherichia coli

Section B

  1. Give general discuss on the UTI.
  2. Explain about the Upper RTI and causes diseases.
  3. Write about the lower RTI.

Section C

  1. Give detail an account on etiology and laboratory diagnosis of UTI to causes Meningitis and Diarrhea.

UNIT -IV

Pyogenic infections- Staphylococcus and Pseudomonas: Sexually Transmitted Diseases Bacteria), Nosocomial infections - definition, sources and detection; phage typing, Bacteriocin typing.

Section A

1. Each of the following statements about the classification of streptococci is correct except
a. Pneumococci (Streptococcus pneumoniae) are alpha-hemolytic and can be serotyped on the basis of their polysaccharide capsule
b. Enterococci are group D streptococci and can be classified by their ability to grow 6.5% sodium chloride
c. Viridans streptococci are identified by Lancefield grouping, which is based on the C carbohydrate in the cell wall
d. Although pneumococci and the viridans streptococci are alpha-hemolytic, they can be differentiated by the bile solubility test and their susceptibility to optochin

2. Which of the following bacteria has the lowest 50% infective dose (ID50)?
a. Campylobacter jejuni
b. Salmonella typhi
c. Vibrio cholerae
d. Shigella sonnei

3. Which of the following disease is best diagnosed by serologic means?
a. Pulmonary tuberculosis
b. Gonorrhea
c. Actinomycosis
d. Q Fever

4. The cogulase test is used to differentiate
a. Staphylococcus epidermidis from Neisseria meningitidis
b. Staphylococcus aureus from Staphylococcus epidermidis
c. Streptococcus pyogens from Staphylococcus aureus
d. Streptococcus pyogens from Enterococcus faecalis

5. Burn patients often develop nosocomial infection caused by?
(a) Corynebacterium spp (b)Staphylococcus aureus (c) Candida albicans.

Ans :b

6.. Clinical microbiology laboratory should contains how many sections?
(a) Seven (b) Eight (c) Ten

Ans :a

7.Which of the following bacteria is not a most common bacterial pathogen causing diarrhea?
a. Shigella spp b. Salmonella spp c. Enterococcus faecalis d. Campylobacter

8.Which of the following bacteria is rarely associated with Urinary Tract Infections?
a. E.coli b. Enterobacter spp c. Proteus spp d. Shigella spp

9. Which of the following statement regarding Campylobacter jejuni is not correct?
a. It is commonly cultured in antibiotic containing media
b. Incubation temperature is 42 Oc
c. It is cultured in an atmosphere containing 5% O2 and 10% CO2 d. It is a normal floraof intestine.

10.Which of the following bacteria is not most important causes of acute bacterial meningitis?
a. Neisseria menigitidis
b. Streptococcus pneumoniae
c. Haemophilus influenzae
d. Streptococcus pyogens

11.Which of the following Gram negative rod is not a blood borne bacterial pathogen?
a. Shigella spp
b. Escherichia Coli
c. Klebsiella pneumoniae
d. Pseudomonas aeruginosa

12.Throat culture is not useful to diagnose
a. Streptococcal sore throat
b. Diphtheria
c. Thrush
d. Pneumonia

13.Stool culture is primarily recommended when the complaint is
a. Bloody diarrhea (dysentery, enterocolitis)
b. Watery diarrhea
c. for both bloody and watery diarrhea
d. an indication of anaerobic infection

14.Which of the following bacteria causing sexually transmitted disease can not be grown on artificial media?
a. Neisseria gonorrhoeae
b. Chlamydia trachomatis
c. Treponema pallidum
d. Both Treponema pallidum and Chlamydia trachomatis

15.Cold agglutinin test is useful for the diagnosis of
a. Mycoplasma pneumoniae
b. H. influenzae
c. N. menigitidis
d. Cryptococcus neoformans

16.Which of the following test is not recommended for the diagnosis of Syphilis?
a. VDRL test
b. Culture
c. FTA-ABS test
d. MHA-TP test

17. Toxic shock syndrome” is caused by the toxin of

1) Staphylococcus aureus (2) Streptococcus pyogenes(3) Vibrio cholerae (4) Candida

18.Causative agent of syphilis

  1. T. pallidum (2) T. pertenue (3) T. carateum (4) T. endemicum

19. Specific test for syphilis is
(1) VDRL (2) ELISA (3) FTA (4) None of these

  1. Pathogenic Staphylococci produces an enzyme_____
    (1) Coagulase (2) Catalase (3) Amylase (4) None of these

Section B

  1. Explain about the phage typing.
  2. Explain about the pyogenic infection of Staphylococcus
  3. Give detail an account on bacteriocin.

Section C

  1. Explain about the pyogenic infection of Pseudomonas
  2. Discuss on the sexually transmitted diseases by bacteria.
  3. Define nosocomial infection , sources and detection.

UNIT –V

Antibiotics and chemotherapeutic agents- Mechanism of actions – Drug resistance – Antimicrobial susceptibility testing- Disc diffusion- Kirby Bauer method

Section A

1. Sensitivity test can be done to check whether the infectious organism is sensitive to ______or not?
(a) Antimicrobial agents (b)Environment (c) Temperature

Ans :a

2.. Susceptibility of microbes to antimicrobial agents is determined by ______
(a) Resistance of microbes to antibiotics(b) Sensitivity to antibiotics (c) Both (d)None

Ans :c

3. All of the following antibiotics bind to the 50S subunit of the ribosome thereby inhibiting proteinsynthesis EXCEPT

a.Chloramphenicol

b.Erythromycin

c.Linezolid

d.Doxycycline

2.Pharmacokinetics of doxycycline

a.20% bound by serum proteins

b.60-70% absorption after oral administration

c.Absorption is impaired by divalent cations, Al3+, and antacids

d.Widely distributed especially into the CSF

3.Which of the following inhibits DNA gyrase?

a.Penicillin

b.Trimethoprim

c.Chloramphenicol

d.Ciprofloxacin

4.Resistance to Penicillin and other  lactams is due to

a.Modification of target PBPs

b.Presence of an efflux pump

c.Inactivation of antibiotics by  lactamase

d.All of the above

5.All of the following are recognised adverse effects of isoniazid EXCEPT

a.Hepatitis

b.Peripheral neuropathy

c.Retrobulbar neuritis

d. Phenytoin metabolism   Phenytoin blood levels and toxicity

6..Regarding fluoroquinolones

a.Ciprofloxacin is ineffective in the treatment of gonococcus

b.Norfloxacin and Ciprofloxacin are predominantly faecally excreted

c.Norfloxacin and Ciprofloxacin have long half lives (12 hours)

d.May damage growing cartilage in children less than 18 years of age

7.Vancomycin

a.Is never orally administered as it is poorly absorbed from the GIT

b.Binds to the 30S unit on the ribosome and inhibits protein synthesis

c.60% of vancomycin is excreted by glomerular filtration

d.Adverse reactions to vancomycin are encountered in about 10% of patients

8.Regarding the “azole” group of antifungals

a.Fluconazole has low water solubility

b.Ketoconazole may be given IV/PO

c.Itraconazole undergoes renal elimination

d.they work by reduction of ergosterol synthesis by inhibition of fungal cytochrome P450 enzymes

9.The fluoroquinolones

a.May be administered to patients with severe campylobacter infection

b.Work by inhibiting dihydrofolate reductase

c.Have little effect against gram positive organisms

d.Are heavily metabolised in the liver

10.Clindamycin

a.Inhibits bacterial cell wall synthesis

b.Is often used for prophylaxis of endocarditis in patients with Valvular disease who are undergoing dental procedures

c.Penetrates through BBB into CSF well

d.Works well against enterococci and gram negative aerobic organisms

11.Which of the following is a second generation cephalosporin?

a.Ceftazidime

b.Cephalothin

c.Cefotaxime

d.Cefaclor

12.The cephalosporin with the highest activity against gram positive cocci is

a.Cefaclor

b.Cephalothin

c.Cefuroxime

d.Cefepime

13.Regarding the penicillins

a.Penicillin ix excreted into breast milk to levels 3-15% of those present in the serum

b.Absorption of amoxyl is impaired by food

c.Benzathine penicillin is given PO

d.Penicillins are 90% excreted by glomerular filtration

14.Rifampicin

a.Inhibits hepatic microsomal enzymes

b.Inhibits DNA synthesis

c.Is bactericidal for mycobacteria

d.Is not appreciably protein bound

15.Regarding resistance to antibiotics

a.Penicillinases cannot inactivate cephalosporins

b.Macrolides can be inactivated by transferases

c.Mutation of aminoglycoside binding site is its main mechanism of resistance

d.Tetracycline resistance is a marker for multidrug resistance

16.Concerning toxicity of antibiotics

a.Enamel dysplasia is common with aminoglycosides

b.Grey Baby Syndrome occurs with rifampicin use

c.A disulfiram like reaction can occur with macrolides

d.Haemolytic anaemias can occur with sulphonamide use

17.Which of the following is considered to be bacteriostatic?

a.Penicillin

b.Chloramphenicol

c.Ciprofloxacin

d.Cefoxitin

18.Half life of amphotericin B is

a.2 seconds

b.20 minutes

c.2 hours

d.2 weeks

19.Regarding antiseptic agents – all of the following are true EXCEPT

a.Sodium hypochlorite is an effective antiseptic for intact skin

b.Potassium permanganase is an effective bactericidal agent

c.Formaldehyde may be used to disinfect instruments

d.Chlorhexidine is active against gram positive cocci

20.Ciprofloxacin

a.Is a defluorinated analogue of nalidixic acid

b.Inhibits tropoisomerases 2 and 3

c.Has no gram positive cover

d.Has bioavailability of 30%

21.Flucloxacillin

a.Is ineffective against streptococci

b.Is active against enterococci and anaerobes