Micro Exam

How would this gram stained smear be described? GPB GNB GPC GNC

GNB

Which one of the following organisms is sensitive to bacitracin? Group A Strep Group B Strep Group D Strep Staph

Group A Strep

The susceptibility of a bacterium to each drug on a sensitivity plate using antibiotic disks is demonstrated by the diameter of the zone of:

Inhibition

What bacteria is responsible for the bubonic plague? Mycobacterium tuberculosis Y. pestis Vibrio cholerae Corynebacterium diptheriae

Yersinia pestis

The image to the right is a GS of a positive blood culture. The bacterial genus most likely to grow out in culture is: Staph Strep listeria corynebacterium

Staph

Which of the following conditions is caused by Trypanosoma cruzi? Malaria Chagas disease Tapeworms Sleeping sickness

Chagas disease

Which organism is classified as an obligate anaerobe? Mycobacteria S. aureus Neisseria species Clostridium novyi

Clostridium novyi

Which of the following organisms produces a double zone of hemolysis on blood agar? Clostridium septicum Clostridium perfringens Clostridium difficile Clostridium tetani

Clostridium perfringens

Which of the following fungal infections is endemic in the SW US desert regions? Histoplasmosis Blastomycosis Coccidiodomycosis Sporotrichosis

Coccidiodomycosis

Which of the following organisms has been isolated from nasal secretions and causes atrophic rhinitis, a tissue destructive disorder in the nose? Cronobacter sakazakii Klebsiella pneumoniae subsp. ozaenae Y. pseudotuberculosis Morganella morganii

Klebsiella pneumoniae subsp. ozaenae

GPC isolated from a catheterized urine culture on a 76 yr old male gave the following rxns: BA - creamy, white, opaque colonies NH Cat - POS Slide coag - neg Tube coag - neg Novobiocin - Sus Next action an MLT should take is: REport as coag neg staph Report as Staph epidermidis Report as Staph saphrophyticus Perform further testing

Report as coag neg staph

An alpha hemolytic slightly concave isolate from a respiratory specimen gave a zone of inhibition of 18mm around the optochin disk. What should the next step be? Report the isolate as optochin sensitive Report this organism as Strep pneumoniae Report this organism as Viridans Streptococci Repeat the optochin susceptibility test

Report this organism as Strep pneumoniae

The purulent exudate and intracellular bacteria was observed in a direct sputum GS of a 70yr old w/ chronic obstructive pulmonary disease. Which bacterial species most likely grew out in culture? Moraxella catarrhalis Neisseria gonorrhoeae Neisseria meningitidis Acinetobacter lwoffi

Moraxella catarrhalis

All of the following are included in a standard O&P exam EXCEPT: Visual exam Direct wet mount Permanent stained smear Parasite culture

Parasite culture

Which term describes the cellular morphology of bacteria with a pointed end? Cocci Coccobacilli Fusiform Bacilli

Fusiform

Select the virus that is transmitted from birds to humans through a mosquito vector: Hepatitis A Rotavirus West Nile CMV

West Nile

All of the following are common causes of infective endocarditis EXCEPT? Strep. mutans Cardiobacterium hominis Staph. epidermidis Corynebacterium jeikeium

Corynebacterium jeikeium

Which of the following is used to standardized bacterial inoculum used in a disk diffusion test? (Kirby-Bauer) 0.1 McFarland standard 0.5 McFarland standard 1.0 McFarland standard 2.0 McFarland standard

0.5 McFarland standard

If mycobacterium sp. infection is suspected on a bone marrow or body fliud, what stain should be used to detect these bacteria? Wright's stain Methylene blue stain Hematoxylin and Esoin stain Acid fast stain

Acid fast stain

Pseudomonas aeruginosa is often used as a bacterial species for the QC of Kligler Iron Agar, The expected rxn is: Acid slant/acid deep Alkaline slant/acid deep Alkaline slant/acid deep/H2S Alkaline slant/alkaline deep

Alkaline slant/alkaline deep

Based on the structures observed in this image, the most probable identity of the fungus recovered from a sputum is: Fusarium spp. Penicillium spp. Aspergillus spp. Syncephalastrum spp.

Aspergillus spp.

A 70 yr old man who 3 days prev. had incurred a cerebral vascular accident was semi-comatose and having difficulty breathing. He developed sudden fever overnight and was found to have pneumonia. The gram stain showin was obtained from purulent material obtained through the intubation tube. What is the most likely type of pneumonia? Lobar pneumonia Aspiration pneumonia Community acquired pneumonia Bronchitis secondary to Moraxella catarrhalis

Aspiration pneumonia Clues: Mixed flora (GPC/GNR), cluster of neutrophils, GPC most consistent w/ S. pneumonia

This organism is found endemically on the New England seacoast. When seen in peripheral blood smears, it resembles a prarasite of the genus Plasmodium. When an organism resembling malarial parasites is found in the peripheral blood, it is most probably: Leishmania donovani Trypanosoma cruzi Babesia Loa loa

Babesia

Which of the following parasites have a life cycle that resembles that of the Plasmodium species? Dracunculus medinensis Blastocystis hominis Babesia microti Toxocara canis

Babesia microti

Which of the following organisms would give the GS microscopic results seen in this image? Bacillus anthracis Corynebacterium diptheriae Listeria monocytogenes Erysipelothrix rhysiopathiae

Bacillus anthracis

Which of the following is a presumtive test for the ID of Lancefield group A strep? Bacitracin susceptibility Positive coagulase Hippurate hydrolsis GS

Bacitracin susceptibility

Which of the following tests should be incubated at 37 in a 5-10% Co2 atmosphere? CAMP Bile solubility Optochin disk test Novobiocin disk

Bile solubility

The India ink preparation is used for presumptive ID of which organism? Aspergillus niger in blood Cryptococcus neoformans in CSF Histoplasma capsulatum in CSF Candida albicans in BF

Cryptococcus neoformans in CSF

A D-test is performed on GPC to determine inducible resistance to clindamycin when the isolate is sensitive to clindamycin and resistant to which antibiotic? Methicillin Vancomycin Cefoxitin Erythromycin

Erythromycin

Which of the following is a common cause of UTIs? Shigella spp. E. coli Mycobacterium tuberculosis Lactobacillus spp.

E. Coli

Which of the following is the most common etiologic agent identified in prosthetic valve endocarditis? Staph. epidermidis Staph. aureus Strep. sanguis Strep. mutans

Staph. epidermidis

A small GNR isolated from an eye grows on chocolate agar and it produces satellite growth around staphylococci colonies on sheep BA. the organism requires: X and V factor X only V only Neither

X and V factor

The beta hemolysis seen around the opaque,flat, spreading colonies of a 5% BA is helpful in differentiating Bacillus cereus from Bacillus anthracis (NH). Each of the following is helpful in differentiating the two EXCEPT: Motility Hydrolysis of gelatin Lecithinase production Fermentation of salicin

Lecithinase production

A combination of nontreponemal testing (VDRL or RPR) and treponemal testing (TP-PA or EIA) is used to confirm: chlamydia herpes syphilis gonorrhea

syphilis

In order to speciate a swarming Proteus organism found on an eosin methylene blue agar plate, the BEST approach would be to: B. determine motility and lysine decarboxylase activity C. determine Indole production and ornithine decarboxylase D. determine deamination of phenylalanine E. determine urease activity

C. determine Indole production and ornithine decarboxylase

Infections with all of the following viruses could cause malignant disease, except: HPV EBV HHV-8 (human herpes virus 8) CMV

CMV

This organism is very similar to Serratia marcescens, except it is DNA'se negative. Kluvera ascorbata Rahnella aquatilis Cedecea davisae Ewingella americana

Cedecea davisae

For an isolate of E. coli, Klebsiella or Proteus species, testing positive for ESBL, all of the following antibiotics report as resistant except: Aztreonam Cefazolin Cefoxitin Ceftriaxone

Cefoxitin

What is the best method of detection of Chlamydia trachomatis in cases of STD? Non-culture EIA Cervical tissue culture Culture of Thayer-Martin agar DNA amplification techniques

DNA amplification techniques

What is the purpose of using alcohol-acetone or acetone in the Gram stain procedure? Fixes all GP organisms Decolorizes all GP organisms Decolorizes all GN organisms Fixes all GN Organisms

Decolorizes all GN organisms

Which organisms are the appropriate stock cultures for QC testing of oxidase production? E. Coli/Kleb. pneumoniae Salmonella typhimurium/E. coli E. coli/ Psudomonas aeruginosa Proteus mirabilis/E. coli

E. coli/ Psudomonas aeruginosa

Protozoa measuring 25 um found in stool. Which does it represent? Iodamoeba buschlii Entamoeba coli Endolimax nana Entamoeba histolica

Entamoeba coli

Which of the following organisms is considered to be pathogenic? Entamoeba histolytica E. Coli Chilomastix mesnili Trichomonas hominis

Entamoeba histolytica

Which of the following organisms is most likely GPC in clusters? Staph. aureus Strep. pneumoniae Corynebacterium spp. Micrococus spp.

Staph. aureus

All of the following organisms stain with an acid fast stain, or one of its variants except? Mycobacterium Cryptosporidium actinomyces Nocardia

actinomyces

What color would the agar be around a colony of Staph. epidermidis growing on Manitol salt agar? Yellow Red Brown Clear

Red

curved, GN rod

campylobacter jejuni

Parasites that belong to the category Sporozoa are also known as: flukes digenea hemoglagellates coccidia

coccidia

Which of the following Mycobacterium species is closely associated w/ infections in HIV positive patients? M. ulcerans M. avium-intracellulare complex M. simiae M. bovis

M. avium-intracellulare complex

This micrograph is most consistent with the cell morphology of: Bacillus cereus Rothia dentocariosa Corynebacterium diptheriae Actinomyces meyeri

Corynebacterium diptheriae

Readings from left to right: ONPG:neg Arginine: pos lysine: pos ornithine decarboxylase: pos citrate: pos H2S: pos remaining rxns neg Which is it? Citrobacter Salmonella Proteus Edwardsiella

Salmonella

The bacterial species that produces these rxns is: Staph. aureus Strep. bovis Enterococcus faecalis Listeria monocytogenes

Enterococcus faecalis (positive for exculin, growth in 6.5% NaCl)

The pathogenicity of staphylococcus aureus, as well as frequency with which this organism produces infections, can be attributed to all of the following EXCEPT: Exfoliative toxin and enterotixins A porous cell wall Natural colonization/resevoir for infection Hyaluronidase

Exfoliative toxin and enterotixins

Which of the following conditions is associated with a typical Bacillus cereus infection? Foot rot Subcutaneous mycetoma Food borne enteritis Alkaline encrusted cystitis

Food borne enteritis

Based on the image to the right, the issued gram stain report should read, "Many WBC with...." GPC GPC in pairs GPR GNC

GPC in pairs

Procedures that may enhance the recovery of Streptococcus pyogenes from throat cultures include: Extraction of streptococcal grouping antigen Incorporation of sulfamethoxazole and trimethoprim in the culture media Incubation at 42C Use of culture media with increase concentrations of glucose

Incorporation of sulfamethoxazole and trimethoprim in the culture media

Which one of teh following statements about Campylobacter jejuni is false? It can occur in domestic animals, raw milk, and undercooked poultry. It does not require special incubation conditions to grow in culture. It is associated with neutrophils in the stool. It is a curved GN rod.

It does not require special incubation conditions to grow in culture.

A sputum specimen submitted for culture is brick red in color. The organism causing this color also has a distinct polysaccharide capsule and is nonmotile. Which organism can be associated with this sputum? Yersiinia Pasteurella Salmonella Klebsiella

Klebsiella

GN intracellular diplococci seen on GS from an 18 yr old woman with a swollen knee joint. She also had cervical discharge that was cultured. Her infection would grow best on: Modified Thayer-Martin agar @ 35 d.C w/ CO2 LIM broth with refrigerated temperature BA @ 42d.C. with microaerophilic conditions V human blood agar @ 35 d.C w CO2

Modified Thayer-Martin agar @ 35 d.C w/ CO2

Each of the following characteristics is prerequisite for bacterial species to be classified within the family Enterobacteriaeceae except: GN organism bacilli shaped Motility via peritrichous flagellae Fermentation of glucose

Motility via peritrichous flagellae

Which of the following is most likely identification of an acid fast bacilli recovered from a sputum? Slow growth @ 37 d.C. Niacin: Neg Nitrate: Pos Cat: Pos Mycobacterium tuberculosis Mycobacterium kansasii Mycobacterium simiae Mycobacterium chelonei

Mycobacterium tuberculosis

Which of the following organisms is an obligate intracellular parasite? Proteus Escherichia Klebsiella Rickettsia

Rickettsia

While many of the isolates of this organism remain susceptible to penicillin, resistance is increasing in some areas due to the organism's altered penicillin binding proteins. IN such cases, the recommended treatment is erythromycin or chloramphenicol. Which of the following organisms does this describe? Enterococcus faecium Staph. aureus Kleb. pneumoniae Strep. pneumoniae

Strep. pneumoniae

With the widespread use of the pneumococcal vaccine, there has been a decline in the incidence of community-acquired pneumonia by which of the following organisms? M. pneumoniae H. influenzae Strep. pneumoniae Chlamydia pneumonia

Strep. pneumoniae

Which of the following statements is true regarding the gram-stained smear that is represented by this image? The smear is underdecolorized and shows precipitated and crystallized stain Many long, needle shaped bacteria are present The smear is appropriate for reading Many GPC are present

The smear is underdecolorized and shows precipitated and crystallized stain

The red ring at the top of the media in this tube indicates Positive indole rxn. the precursor substance in the medium from which the indole is prduced is: Tryptophan p-dimethylaminobenzaldehyde Pyruvic Acid Peptone

Tryptophan

This member of the Enterbacteriaceae was isolated from a stool specimen and gave the following biochemical rxns: TSI: K/A, no gas, no H2S Citrate: Pos Lysine decarboxylate: Neg Ornithine decarboxylase: Pos Indole: Neg This org. agglutinated in Group D Shigella antiserum All of the above are consistent with EXCEPT: TSI Citrate Lysine Indole

Citrate Shigella sp. are citrate negative. Otherwise they are all consistent with Shigella sonnei

Which bacterial species listed is a select agent, which is capable of producing an extremely potent, lethal neurotoxin? Aggregatibacter aphrophilus Moraxella catarrhalis Clostridium botulinum Corynebacterium striatum

Clostridium botulinum

The serum medium and methylene blue stain originally described by Loeffler are both helpful in the identification of: Bordetella pertussis Corynebacterium diptheriae Streptobacillus moniliformis Gardenerella vaginalis

Corynebacterium diptheriae

An unidentified colony was inoculated to the surface of a filter paper strip impregnanted with cytochrome oxidase reagent. (POS). The family of bacteria ruled out by the rxn seen is: Pasteurellae Neisseriaceae Enterbacteriacae Pseudomonadaceae

Enterbacteriacae

Which of the following is most commonly used as a routine staining technique in the clinical micro lab? Wrights Gram Giemsa Wrights/Giemsa

Gram

The following is the best test to differentiate between Aeromonas hydrophila and E. coli from a wound culture: GS Oxidase Glucose Fermenter Lactose Fermenter

Oxidase

All of the following bacterial species produce a yellow pigmented colony when growing on a 5% sheep blood agar EXCEPT: Cronobacter sakasakii Serratia rubidaea Pantoea agglomerans Micrococus luteus

Serratia rubidaea

A pt presents w/ severe diarrhea and dehydration marked with rice water stool. The patient has travel history to India. A stool culture was obtained and grew comma-shaped, GN bacilli. What is the most likely diagnosis? cholera plague Campylobacter Typhoid fever

cholera

Which of the following terms is used to describe the appearance of rod shaped bacteria? budding septate filamentous lancet

filamentous

Helicobacter pylori could not be recovered from gastric biopsies but was seen in the tissue sections. Protocol is to switch from Campy BAP selective medium to Skirrow's BA b/c? Free of cephalothin Incorporates lysed horse instead of sheep blood Free of amphotericin B Has reduced concentrations of vancomycin and trimpthoprim

Free of cephalothin

The image of the GS is from a positive blood culture. Which is the most appropriate report that the tech should provide? GPC GPC in chains GPC consistent with Strep spp. GPC consistent with Enterococcus

GPC in chains

The biochemicla testing results of an alpha-hemolytic strep show that the isolate is bile escolin positive, but does not grow in 6.5% NaCl. The most probable identity is: Group B strep Group D strep, enterococcus Group D strep, non-enterococcus Viridans strep

Group D strep, non-enterococcus

Acute obstructive epiglottis, both in adults and children, is most commonly cuased by a specific bacterial species that can be recovered on chocolate agar and requires both hematin and NAD. Most likely ID is: H. parainfluenzae H. influenzae H. aphrophilus H. haemolyticus

H. influenzae

If CSF tubes numbered #1, #2, and #2 CANNOT be analyzed within one hour, the correct procedure for the microbiology sample tubes is to: Refrigerate it Freeze it Leave it at room temp Incubate it in a 56 degree water bath

Leave it at room temperature

Buffered charcoal yeast extract agar is the nonselective solid culture medium used for the primary recovery of: Treponema pallidium Mycoplasma pneumoniae Legionella pneumophila Spirillum minus

Legionella pneumophila

The colonies growing on the surface of a thiosulfate citrate bile sucrose agar plate (green indicates lack of sucrose fermentation) were identified as Vibrio vulnificus. The serious complication of infections with this bacterial species is: Life-threatening septicemia Cholera-like diarrhea Severe electrolyte imbalance Progressive cellulitis and gas gangrene

Life-threatening septicemia

Which organism matches the rxns below? Motility agar: POS Esculin Hydrolysis: POS Voges-Proskauer: POS Erysipelothrix rhusiopathiae Arcanobacterium haemolyticum Corynebacterium spp. Listeria monocytogenes

Listeria monocytogenes

Which of the following substances produced by Group A Streptococci is responsible for producing type specific immunity? Streptolysin O Streptolysin S M antigen T antigen

M antigen

Each of the following parasites, whose common names are listed, is associated w/ intestinal infections except: Whipworm Dwarf tapeworm Malayan filarial worm Pinworm

Malayan filarial worm

The upper photomicrograph illustrates a GS of a sputum obtained from a 55 yr old man w/ symptoms of bacterial pneumonia. The lower photograph represents the growth of an inoculum from the specimen on 5% BA on which optophin and a 1ug oxacillin disk were placed. AFter 18 hrs incubation @ 37 d.C. in 5% CO2, the zone around teh optochin disk is 18mm and the OX disk is 8mm. The interpretation is most likely: Normal flora, not cause of pneumonia Viridans group strep, penicillin sensitive Pneumococcus, penicilin resistant Pneumococcus, penicillin sensitive

Pneumococcus, penicilin resistant

Each of the following lab findings will confirm the presumptive diagnosis of C. diff associated colitis EXCEPT: Recovery of c. diff in the stool Detection of cytotoxin B of C. diff + latex agglutination of glutamate dehydrogenase of C. diff + EIA for C. diff enterotoxin

Recovery of c. diff in the stool (have to prove the strain is toxin producing)

Which of the following is a key benefit that molecular methods can offer over culture methods? Reduced cost per test Reduced TAT Decreased sensitivity of detection Increased TAT

Reduced TAT

The appearance of the bacterial colonies growing on the surface of a HE plate would be yellow for all of the following EXCEPT: Serratia marcensens Shigella sonnei Klebsiella oxytoca Enterbacter sakasakii

Shigella sonnei

This member of the enterbacteriaceae is shown on TSI, Lysine agar, urea, citrate, phenylalanine deaminase, and motility indole. E. coli Salmonella sp. Shigella sonnei Providencia spp.

Shigella sonnei Sucrose/Lacrose NF H2S neg Lysine neg urea neg citrate neg phenylalanine neg ornithine pos indole neg non-motile

Which of the following Staphylococcus species will produce yellow colonies on mannitol salt agar? Staph. aureus Staph. saphrophyticus Staph. epidermidis Staph. haemolyticus

Staph. aureus

Which of the following corresponds to a way to prevent infection with Sporothrix schenckii? Avoid caves Avoid areas of roosting birds Wear gloves when gardening Wear shoes when showering in a public shower

Wear gloves when gardening

A pt seen in the ED has symptoms consistent w/cellulitis. A GS from the pt's BC revealed GPC in pairs and short chains. BC grew and organism that was susceptible to a 0.04 unit disk of bacitracin. Other characteristics include: beta hemolysis, Neg catalase, Neg CAMP, growth 6.5% salt beta hemolysis, Neg catalase, POS CAMP, neg 6.5% salt beta hemolysis, Neg catalase, Neg CAMP, neg 6.5% salt beta hemolysis, POS catalase, POS CAMP, neg 6.5% salt

beta hemolysis, Neg catalase, Neg CAMP, neg 6.5% salt