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415 Cards in this Set
- Front
- Back
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Types of fungal infections include...
(3 answers) |
-superficial
- subcutaneous
- systemic |
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The KOH test is... |
less sensitive than the Calcofluor White test |
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Molds form filamentous colonies of various colors and textures. The filamentous growth is called the... |
Mycelium |
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One reason to perform susceptibility testing on a fungal isolate is... |
the patient has failed therapy |
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An organism from a lung biopsy grew was a mold at room temperature and yeast at 37 degrees Celsius. What is the most appropriate way to interpret these? |
A dimorphic fungus is present |
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Most fungal cultures are incubated... |
at 30 degrees Celsius for 4-6 weeks |
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A 10% potassium hydroxide (KOH) preparation is used when specimens of skin or tissue are to be examined for fungal elements. The KOH _________ the host cellular material, allowing fungal elements to be more easily seen. |
digests |
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The formation of germ tubes presumptively identifies... |
Candida albicans |
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A sputum specimen from a patient with a known Klebsiella pneumonia infection is received in the laboratory for fungus culture. The proper procedure for handling this specimen is to... |
include media that have cycloheximide and chloramphenicol added to inhibit bacterial organisms and saprophytic fungi |
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What is an example of a rapid yeast identification method?
(3 answers) |
-Uni-Yeast Tek
- API-20C
- CHROMager |
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Dermatophytes are most often seen in specimens from hair, ______, and _______. |
skin and nails |
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What colors are seen in yeast colonies?
(4 answers) |
- cream
- tan
- pink
- coral |
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Yeast isolated from an oral lesion in a one-month-old infant was inoculated into calf serum for a germ tube test. After several hours incubation, the presence of straight-sided, elongated structures were evident from the ends of the yeast cells. There was no constriction at the junction of the yeast cell. How would interpret these results? |
germ tube positive |
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The India Ink prep is used to detect... |
the capsule of Cryptococcus neoformans |
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What best describes the Zygomycetes? |
Fungus with broad, ribbon hyphae |
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Lab workers should always work under a biological safety hood when working with cultures of... |
Coccidiodes immitis |
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What is a stain for fungus?
(3 answers) |
- PAS
- KOH
- Calcoflour |
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Most years form visible colonies within _______ days on standard agar |
2-3 |
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The wet mount can be used to determine if an isolate is _______ or ________ |
yeast, bacteria |
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What is a stool concentration method for parasites?
(2 answers) |
- sedimentation
- flotation |
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Specimens for stool parasitology must be placed in preservatives if not received in the laboratory within... |
30 minutes |
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When collecting a specimen for Enerobius vermicularis (Pinworm), the specimen is collected... |
using a cellophane tape preparation |
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Parasites are organisms that...
(3 answers) |
- live on or within another organism
- live at the expense of another organism
- are usually restricted to specialized environments inside and outside their hosts |
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What personal protective equipment must be worn when the technician is working with specimens that may contain parasites? |
Gloves and a lab coat |
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When collecting specimens for stool parasitology... |
3 specimens are collected on different days |
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What lives close to the human scalp to maintain their body temperature? |
head lice |
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What is the best stain for blood parasites? |
Giemsa stain |
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What stain technique requires the use of 70%, 95%, and 100% ethanol? |
Trichrome stain |
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The Modified Acid-Fast staining procedure is used to detect what organisms from stool specimens?
(3 answers) |
- Cryptosporidium
- Isospora
- Cyclospora |
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Which stool specimens are given a direct visual evaluation prior to processing for parasites?
(3 answers) |
- Presence of blood/or mucous
- Presence of parasitic structures
- Consistency |
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Which parasite can be acquired from oocytes present in cat feces? |
Toxoplasma gondii |
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Common anthropoids sent to the parasitology laboratory for identification include...
(3 answers) |
- lice
- fleas
- ticks |
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When preparing slides for blood parasite staining, _____ slides (___________) should always be prepared |
- 2
- think and thin) |
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When venous blood is used to prepare blood smears for parasitology examination, a delay in preparation of the slide from the blood specimen can result in changes in… |
Parasite morphology and staining characteristics |
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Whenever possible, specimens for blood parasitology should be... |
collected before treatment is initiated |
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The advantage of thick blood smears for malarial parasites is to... |
improve detection of the organisms |
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Which parasites must be reported to the Arizona state health department? |
Entamoeba histolytica |
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Which eggs from a common parasite of children has one side slightly flattened? |
Enterobius vermicularis |
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A patient is having amebic dysentery. Upon microscopic examination of a trichrome smear for ova and parasites, the following data were obtained: 1. A trophozoite of 25m, 2. Evenly distributed peripheral chromatin around a single nucleus, 3. Finely granular cytoplasm. This information most probably indicates... |
Entamoeba histolytica/ E. dispar |
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Which parasite can be found in sputum and fecal specimens and has large, thick-walled eggs with mamilations? |
Ascaris lumbricoides |
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Fasciolopsis buski is... |
the largest trematode to infect humans |
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What is the only ciliated protozoan known to infect humans? |
Balantidium coli |
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Cyclospora cayetanensis oocysts are... |
larger than Cryptosporidium parvum oocysts |
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Charcot-Leyden crystals... |
are the breakdown products of eosinophils |
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In parasitology, what instrument is used to give an accurate measurement of objects under the microscope? |
Ocular micrometer |
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When protozoan cysts with 7-8 nuclei are seen in an ova and parasite exam, the most likely identification is... |
Entamoeba coli |
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Large glycogen vacuoles are associated with what protozoan amoeba? |
Iodamoeba butschlii |
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A trichrome stain of a stool specimen demonstrated the presence of organisms that averaged 6-10um. The organisms were oval to round and contained 4 large nuclei with no peripheral chromatin. What is the most likely identification? |
Endolimax nana |
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What intestinal parasites must be quantified when it is reported? |
Blastocystis hominis |
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This tapeworm is acquired by eating undercooked fish. Its eggs have an operculum and an abopercular knob. |
Diphyllobothrium latum |
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Which coccidian parasites are positive with the acid-fast stain?
(3 answers) |
- Cryptosporidium parvum
- Cyclospora cayetenensis
- Isospora belli |
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Parasitic life cycles are _________ to diagnosis in the patient. |
imparitive |
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Which two parasites have NO known cyst stage? |
Dientamoeba fragilis and Blastocystis hominis |
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This photo is of what schistosome? |
Schistosoma haematobium |
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This photo is of what most common protozoan parasite found in the US? |
Giardia lamblia |
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Which is the agent for African sleeping sickness? |
Trypanosoma brucei |
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Which organism is known to infect eyes? |
Acanthoamoeba spp. |
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Leishmaniasis is a cutaneous parasitic disease caused by... |
a transmition by a sand fly |
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Naegleria fowleri |
is a free-living amoeba with lobed pseudopodia |
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Which protozoan has the typical "Maltese Cross" form seen in the RBC's of an infected patient? |
Babesia spp. |
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Which species of malarial parasite produces the characteristic crescent-shaped gametocytes? |
Plasmodium falciparum |
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Band-shaped trophozoites forms are characteristic of which malarial species? |
Plasmodium malariae |
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Thin blood film examination for malaria is... |
considered a STAT procedure |
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What blood component may mimic malarial parasites when seen on top of a red blood cell in a thin smear? |
platelet |
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The organism fluoresces with the Calcofluor white stain |
Acanthamoeba spp. |
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Which Plasmodium species are amoeboid trophozoites seen most often? |
Plasmodium vivax |
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Plasmodium species are transmitted by... |
mosquitoes |
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Trichinella spiralis is typically found in what undercooked meat? |
pork |
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Ticks transmit... |
Babesia species to humans |
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What is a sheathed microfilaria?
(3 answers) |
- Wuchereria bancrofti
- Brugia malayi
- Loa Loa |
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This picture is an example of... |
Trypanosoma spp. |
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The fimbrianated ends of the RBCs in the picture are typical of what Plasmodium species? |
Plasmodium ovale |
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This photo shows strippling associated with Plasmodium vivax. What is the name of these dots when they are seen in infected RBCs? |
Schuffner's dots |
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This photo is of what malarial form? |
Trophozoites |
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A cell contains food (nutrients) from the environment to produce ____________ for metabolism and other activities |
energy |
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The prokaryotes, once thought to be a single domain, are now... |
divided into 2 domains, the Bacteria and the Archaea |
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All bacteria...
(3 answers) |
- lack the membrane-bound nuclei of eukaryotes
- contain plasmids, or small loops of DNA, that can be transmitted from one cell to another
- have a peptidoglycan layer in their cell wall when they have a cell wall |
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The nucleus of a eukaryotic cell contains... |
the cell's DNA |
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Microorganisms capable of causing damage to the host through infectious diseases are termed... |
pathogens |
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Virulence factors include...
(5 answers) |
- attachment - invasion - survival against inflammation - survival against the immune system - microbial toxins |
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The spread of pathogens through direct contact with an infected person happens via...
(3 answers) |
- droplet infection
- smear infection (fecal-oral transmission)
- sexual contact |
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Viruses...
(2 answers) |
- depend on the energy and metabolism of the host cell in order to reproduce
- are obligate, intracellular parasites of cellular organisms |
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Up to ________ species of microorganisms live on or in the body of a normal, healthy individual |
100 |
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The function of the Clinical Microbiology Laboratory is to...
(2 answers) |
- analyze and manage specimens
- communicate effectively with the healthcare professionals |
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What is aseptic technique? |
it is a way of performing work to prevent contamination of microbiological cultures and personnel |
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Is it acceptable to apply lip balm in the microbiology lab? |
No |
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Scalpel blades are disposed of in __________ containers |
sharps |
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Where should culture plates with potential air-borne organisms be opened? |
in a biosafety hood or biological safety cabinet |
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What solution should be used to clean biological spills? |
10% bleach |
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When you are finished using your microscope, what steps do you take before leaving the bench?
(4 answers) |
- remove slide from stage - clean all lenses with lens paper and lens cleaner - place lowest power objective under the body tube - center the mechanical stage, and turn off the lamp |
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Why do we clean benches in the microbiology laboratory before and after use? |
because we assume the laboratory areas are contaminated when we enter the lab and after working at the bench |
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Pagers and cell phones must be turned ________ while in the microbiology laboratory |
off |
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Sandals and open-toed shoes are... |
not allowed in the microbiology laboratory |
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What is the most important part of the hand washing process? |
the mechanical action of rubbing the hands together and soaping under the fingernails |
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What are the container(s) used when collecting a blood culture?
(3 answers) |
- an aerobic bottle
- an anaerobic bottle
- vacutainer tubes with SPS |
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Specimens should be collected... |
prior to the administration of antibiotics |
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When a specimen is properly labeled, it is, at a minimum, labeled with the ________ and ______ |
patient name, ID#, and specimen source |
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What should the patient be instructed to do prior to collection of a sputum for culture? |
Rinse their mouth with water and gargle prior to collection |
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How many stools specimens per day are typically collected for culture? |
one per day |
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Any result the laboratory generate is limited by...
(2 answers) |
- the quality of the specimen collected
- the condition of the specimen when it arrives |
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The purpose(s) of transport media is/are...
(4 answers) |
- prevent drying of the specimen
- maintain the appropriate pH level
- preserve the viability of the pathogen
- prevent overgrowth by contaminants or usual flora |
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Reasons for specimen rejection is/are...
(4 answers) |
- improper specimen labeling
- improper transport temperature
- specimen is leaking
- specimen transport time is excessive |
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Terms used to describe colony size...
(3 answers) |
- pinpoint
- large
- small |
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MacConkey agar is a _________ media |
selective |
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Which are the 2 main organisms that are not able to grow on sheep blood agar plates but can grow on chocolate agar plates? |
Heamophilus species and Neisseria gonorrhoeae |
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What is the appearance of colonies growing on Hektoen agar when the organism growing reduces sulfur to hydrogen sulfide? |
black |
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What does selective media contain that is generally used to enhance the growth of bacterial pathogens? |
contains antibiotics to enhance the growth of certain bacterial pathogens |
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What does Enrichment media contain that is generally used to enhance the growth of bacterial pathogens? |
Contains supplements that enhance the growth of a specific bacterial pathogen |
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In beta hemolysis, a ______ zone is seen around the bacterial growth on a blood agar plate |
clear |
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Give two examples of Nutritive (supportive) media |
- Chocolate agar
- Blood agar |
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Streptolysins, the hemolysins produced by streptococci, perform better in _______ environment |
anaerobic |
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The fermentation of lactose by organisms growing on MacConkey agar produces an __________ environment causing the neutral red indicator to turn red |
acidic |
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Hektoen Enteric Agar (HE) is a selective and differential medium containing bile salts and dyes designed to allow the growth of ________ and ________ while slowing the growth of most non-pathogenic Gram negative bacilli found in the gastrointestinal (GI) tract as well as most Gram positive organisms |
Salmonella and Shigella |
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Most bacteria pathogens multiply best at temperatures similar to those of internal human host tissue and organs. For this reason, microbiological incubators are kept at what temperature? |
35C to 37C |
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In which type of hemolysis are red blood cells partially broken down leaving a greenish discoloration of blood agar plates? |
alpha hemolysis |
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What points is/are used in the evaluation of positive cultures?
(4 answers) |
- correlate clinical diagnosis and specimen source - correlate direct gram stain results and culture results - correlate growth on various media - differentiate Normal flora versus potentially significant isolates |
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What word describes organisms that prefer to grow in higher carbon dioxide environments? |
Capnophiles |
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What are examples of bacterial colony shape or surface appearance?
(5 answers) |
- mucoid - glistening - transparent - dull - raised |
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What color colonies are seen on MacConkey agar when the organism growing is unable to ferment lactose? |
colorless |
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Media inoculation of microbiological specimens is... |
performed using a biological safety cabinet or laminar flow hood |
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Which media is the least inhibitory and is inoculated first to minimize carryover of inhibitory substances? |
Chocolate agar |
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The Acridine Orange stain is what type of stain? |
Flourescent |
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Common artifacts you may see in wet prep exams are... |
cotton strands from the swab, hair, air bubbles, and occasionally, crystals |
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You are testing Gram's stain reagent for quality control and you get the following results...
Escherichia coli blue bacilli Staphylococcus aureus blue cocci
The best interpretation of these results is... |
no decolorizer was added |
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The organism Staphylococcus aureus is BEST described by which Gram stain reactions? |
Gram positive cocci |
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A clinical laboratory technician wishes to examine a Gram-stained smear for bacteria and yeast. Which types of microscopes would be the best to use in this scenario? |
Brightfield |
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Trichomonas vaginalis exhibits...
(4 answers) |
- twitching motility
- four anterior flagella
- a short undulating membrane
- oval trophozoites |
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In the differential staining technique (Gram's stain technique) for bacteria, the counterstain is... |
safranin |
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What stain is most likely to demonstrate the presence of encapsulated yeast in a cerebrospinal fluid specimen? |
India Ink |
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A clinical laboratory technician performs a Gram's stain on a cervical sample collected from a healthy 35 year old female. When examined under the microscope, all the bacteria on the slide were colored pink. What is the most appropriate course of action? |
repeat stain and make sure iodine is added |
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Using the endospore stain, a few bacteria such as ___________ and _________ are found to be positive for forming endospores |
Bacillus and Clostridium |
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A beta hemolytic colony on sheep blood is stained and found to be Gram positive cocci. The catalase test is positive and the coagulase test is positive. The organism is most likely...
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Staphylococcus aureus
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An optochin disk test was performed on an unknown gram positive cocci. There was a zone of inhibition greater than 16mm around the disk. The organism also tested positive on the bile solubility test. The most likely identification is...
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Streptococcus pneumoniae
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What organism group forms as "string" in the KOH string test when using the bile solubility reagent?
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Escherichia species
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An organism that exhibits the satellite phenomenon around colonies of staphylococci is...
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Haemophilus influenzae
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In a positive PYR test, the addition of a cinnamaldehyde reagent causes a ________color to be produced
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red
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The oxidase test is most often used to differentiate...
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gram negative bacteria
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The ONPG test allows organisms to be classified as lactose fermenters by testing what?
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beta-galactosidase
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The urease test is used to determine the ability of an organism to split urea by the action of an enzyme urease forming 2 molecules of ammonia. Ammonia increases the pH and its presence is detected...
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using a pH indicator which turns bright pink
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A positive bile esculin reaction is __________
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dark brown to black
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The most common bacteria isolated as a cause of urinary tract infections is Escherichia coli. What is the reaction of E. coli if subjected to the indole test?
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the test would be positive
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An organism that grows as a small, clear beta-hemolytic colony on sheep blood agar, stains as a gram-positive cocci, and is catalase negative is MOST likely to be which of the following?
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Streptococcus pyogenes
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Which staphylococcal species is the most virulent encountered in the clinical laboratory?
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S. aureus
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Staphylococcus aureus produces toxin-mediated diseases ___________ and ___________
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scalded skin syndrome and toxic shock syndrome
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Which is the key to virulence in Streptococcus pneumoniae?
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capsule
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Streptococcus agalactiae is...
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a Group B beta-hemolytic streptococci
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In which type of hemolysis seen in streptococci are the red blood cells in the blood agar only partially lysed resulting in a greenish discoloration of the agar?
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alpha
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The viridans streptococci are typically _______ or ________ hemolytic
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alpha or gamma
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Which 2 tests are always positive for Enterococcus species usually isolated from humans?
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PYR and LAP
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The optochin disk test is used to...
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identify Streptococcus pneumoniae
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Novoviocin is used to differentiate ___________ from ____________
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Staphylococcus saprophyticus from Staphylococcus epidermidis
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Staphylococcus epidermidis is...
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the most commonly encountered coagulase negative staphylococci and is an opportunistic pathogen
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An organism that grows as a small, grey, glistening, alpha-hemolytic colony on sheep blood agar that dips down in the center like a doughnut is MOST likely...
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Streptococcus pneumoniae
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Many enterococci have acquired resistance to vancomycin. The potential for transfer of this gene to what organism genus represents a serious public health threat?
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Staphylococcus
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The viridans streptococci can be differentiated from Streptococcus pneumoniae by...
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bile solubility
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What is the most common bacterial cause of acute pharyngitis?
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Streptococcus pyogenes
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Staphylococcus aureus can be differentiated from Staphylococcus saprophytic us by which test?
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coagulase test
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Which is known as the "flesh eating" bacteria?
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S. pyogenes
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Morphologically, in gram stain, S. pneumoniae exhibits...
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lancet-shaped cocci in pairs
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What is a pigment seen in Micrococcus species colonies?
(3 answers) |
- white
-yellow - orange |
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Abiotrophia species (nutritionally variant streptococci)…
(3 answers) |
- will not grow on blood agar unless vitamin B6 is supplied
- grows when blood culture media is cross-streaked with Staphylococcus aureus - resemble viridans streptococci |
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Which feature distinguishes Erysipelothrix rhusiopathiae from other clinically significant non-spore forming, gram-positive bacilli?
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H2S production
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Corynebacterium diphtheriae is spread by...
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person-to-person contact or may be transferred by exposure to contaminated objects
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What is an anaerobic gram-positive cocci?
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Peptostreptococcus anaerobius
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Corynebacterium does not produce...
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spores
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The potentially lethal intoxication type of food poisoning associated with improperly canned food is caused by...
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Clostridium botulinum
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Bacillus cereus is ___________________ that has been shown to cause food poisoning
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an endospore-forming Gram-positive rod
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Clostridium difficile is associated with...
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pseudomembraneous colitis
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which has "molar tooth" colony formation on plated media?
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Actinomyces israelii
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What is known as an anaerobic diphtheroid?
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Propionibacterium species
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Which Bacillus species is most likely to be used as a weapon of mass destruction?
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Bacillus anthracis
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Which agent typically causes an infection as a result of animal exposure?
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Erysipelothrix rhusiopathiae
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Lactobacillus is...
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a necessary bacterium for a healthy balance in the female vaginal tract
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Colonies of Lactobacillus are...
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alpha hemolytic
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On Gram stain, Actinomyces species...
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can be beaded or branching Gram-positive rods
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Pediococcus and Leuconostoc are...
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resistant to vancomycin
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A gram-positive bacilli with a narrow zone of hemolysis is isolated from a blood culture. A motility test is preformed and an umbrella-shaped motility is seen in semi-solid media. The organism is MOST likely...
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Listeria monocytogenes
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Clostridium botulinum and Clostridium tetani produce_______ endospores
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subterminal
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Clostridium perfringens is known for __________ and _______
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large boxcar-shaped rods and a double-zone of hemolysis
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Definitive identification of Corynebacterium diphtheria requires...
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demonstration of toxin production in the isolate in question
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The Enterobacteriacae shows which reactions? (3 answers) |
- oxidase negative - glucose fermenting - reduce nitrate |
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What plate should the organism be taken from when performing an oxidase test on Gram-negative rods? |
blood agar |
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Most Escherichia coli are __________ on MacConkey agar and _________ on EMB agar |
- pink -black |
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Colonies of Klebsiella pneumonia can be quite mucoid because... |
the organism of the capsule production |
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Colonies of ___________ are black on Hektoen enteric (HE) agar due to H2S production |
Salmonella species |
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A small, opaque, non-hemolytic colony is isolated from an animal bite. The organism had the following characteristics: Gram-negative rods, oxidase positive, and non-motile. The organism can tentatively be identified as... |
Pasturella sp. |
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The bacterium most often responsible for "pinkeye" is… |
Haemophilus sp. |
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A uretheral sample is positive for kidney bean-shaped Gram-negative diplococci by direct Gram stain. The colony did not grow on MAC but grew well on CHOC. What is the MOST likely identification? |
Neisseria gonorrhoeae |
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A thin, anearobic, Gram-negative bacillus with tapered ends is isolated that does not grow on KVLB agar. Colonies were described as "speckled" or resembling "bread crumbs". The most probable identification of the isolate is... |
Fusobacterium nucleatum |
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What is a typical characteristic of Campylobacter jejuni? |
it is motile |
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A TSI tube inoculated with an organism gave the following reactions: Alkaline slant, Acid butt, no H2S, no Gas This organism is most likely... |
Shigella dysenteriae |
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A patient who has a ventilator has developed a severe respiratory infection. Sputum culture shows heavy growth of mucoid, green, beta-hemolytic colonies on blood agar. The organism grows well on MacConkey agar. What is the MOST likely agent? |
Pseudomonoas aeruginosa |
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The most common anaerobic gram-negative bacilli isolated from clinical specimens are... |
the Bacteriodes fragilis group |
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A sputum culture form an alcoholic in the ER shows gray, mucoid stringy colonies on BAP. Isolate grows readily on MAC and forms mucoid, dark pink colonies. The colonies yield the following test results: ONPG positive, indole negative, Glucose positive, Oxidase negative, Citrate positive, VP positive The organism is most likely... |
Klebsiella pneumoniae |
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What 3 organisms are members of the HACEK group? |
- Kingella kingae - Eikenella corrodens - Haemophilus aphrophilus |
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While swimming in a lake near his home, a young boy cut his foot as he stepped on a piece of glass from a broken bottle. An infection developed and the site was cultured. A non-fastidious Gram-negative, oxidase-positive, beta-hemolytic, motile bacillus was recovered. The organism was most probably identified as... |
Aeromonas hydrophilia |
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A non-fermenting, aerobic Gram-negative bacillus is isolated from a wound. The oxidase is strongly positive. The organism produces a shiny blue-green pigment with a metallic sheen on sheep blood agar. The organism is a species of... |
Pseudomonas |
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A small gram-negative rod is isolated form an eye culture. It grows only on chocolate agar and is oxidase-negative. The MOST likely organism is... |
Haemophilus influenzae |
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A motile Gram-negative bacilli that is responsible of 80% of community urinary tract infections is... |
Escherichia coli |
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Which set of organism would be BEST for positive and negative controls for the Citrate Utilization Test? |
Klebsiella pneumonia and Escherichia coli |
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Which of the small Gram-negative rods is a non-lactose fermenting organism that is oxidase-negative and does not reduce nitrate? It has been known to have resistant variants that cause opportunistic infections in hospitalized patients |
Acinetobacter baumanii |
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The organism Escherichia coli is BEST described by which gram stain reaction? |
Gram negative rod |
|
|
The urease test is used to determine the ability of an organism to split urea by the action of an enzyme urease forming 2 molecules of ammonia. Ammonia increases the pH and its presence is detected... |
using a pH indicator which turns bright pink |
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|
Inoculation is performed with a straight needle by stabbing to the base of the butt (within 3-5mm) form the bottom) and then streaking the slant when the needle is removed. This is a description of what test? |
Triple Sugar Iron Agar Test |
|
|
What organism group forms a "string" in the KOH string test? |
Vibrio species |
|
|
In the nitrate reduction test, a red color indicates... |
reduction of nitrite to nitrate |
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An organism gives the following reactions: TSI alkaline slant over an acid butt, H2S positive, ferments glucose. Based on these reactions, what is the most likely identification of the organism? |
Proteus mirabilis |
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Characteristic identification criteria for Moraxella catarrhis include... |
butyrate disk positive |
|
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An organism that exhibits the satellite phenomenon around colonies of hemolytic staphylococci is... |
Haemophilus influenzae |
|
|
Escherichia coli could be used as the positive control organism for which 2 tests? |
-indole -motility |
|
|
The organism Neisseria gonorrhoeae would BEST be described by what gram stain reaction? |
gram negative cocci |
|
|
In the TSI test, production os hydrogen sulfide requires... |
an acidic environment and is manifested by the blackening of the media |
|
|
The oxidase test is most often used to differentiate... |
gram negative bacteria |
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|
Methyl Red (MR) and Voges Proskauer (VP) test are often run together. A positive MR reaction indicates mixed acid fermentation while a positive VP reaction indicates acetoin production. Both positive MR and VP reactions are indicated by a __________ color reaction in the tube |
red |
|
|
What organism is positive in the butyrate disk test? |
Moraxella catarrhalis |
|
|
The ONPG test allows organism to be classified as lactose fermenters by testing for... |
beta-galactosidase |
|
|
Helicobacter pylori is known for its association with... |
Gastritis and peptic ulcers |
|
|
One should always look at both the Blood agar and MAC or EMB agar plates and compare growth when looking at... |
gram negative rods |
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Standardization of the conditions of susceptibility testing serves to maintain __________ and __________ of results so that the same organism will produce the same resistance profile, regardless of which microbiology lab performs the test |
consistency and reproducibility |
|
|
CLSI guidelines are utilized in the clinical laboratory to... |
direct antimicrobial susceptibility patient testing and quality control |
|
|
Most Kirby-Bauer susceptibility tests are... |
incubated in ambient air (CO2) |
|
|
When preparing an organism suspension for susceptibility testing, the suspension is compared to a MacFarland Standard to make certain the suspension has the correct ___________ |
tubidity |
|
|
The term "in vivo" refers to... |
conditions within the body |
|
|
In agar disk susceptibility testing, what are 3 items for which Mueller-Hinton agar is standardized? |
- depth - cation content - pH |
|
|
What is the primary goal of antimicrobial susceptibility testing? |
Determine if the patient is going to respond to therapy with the antimicrobial agents that are available to treat their infection |
|
|
In agar disk susceptibility testing, as an antimicrobial agent diffuses away from the disk, the concentration gradient is... |
decreased |
|
|
The pattern of inoculation of a Kirby-Bauer plate includes streaking the organism suspension in ______ planes |
3 |
|
|
When discussing disk diffusion interpretations in antimicrobial susceptibility testing it must be clearly understood that the interpretations of "susceptible", "intermediate", and "resistant" are based on ____________ levels of the antibiotic which are achieved with the usually recommended dosage. |
Blood or serum |
|
|
In the clindamycin induction test, a flattening of the zone in the area between the erythromycin and clindamycin disks indicate that… (2 answers) |
- the organism has inducible clindamycin resistance - the patient may fail therapy if treated with clindamycin |
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|
Thickness of the Kirby-Bauer agar plates is a crucial component of drug distribution in the agar medium. How thick should the agar be for appropriate results? |
5mm |
|
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In the Disk Diffusion susceptibility test, the reason there is a circular zone of inhibition in which the amount of antibiotic exceeds inhibitory concentration is because growth of the organism and diffusion of the antibiotic commence... |
simultaneously |
|
|
When an organism is not inhibited by concentrations of the antimicrobial that can be achieved in serum even with increased dosage, it is considered _______ to the antibiotic |
resistant |
|
|
Antimicrobial resistance that results from the normal, genetic, structural, or physiologic state of the microorganism is known as... |
intrinsic resistance |
|
|
Group A Streptococci are ____________ when tested against the bacitracin disk |
susceptible |
|
|
When an organism is inhibited by concentrations of the antimicrobial that can be achieved in serum with routine dosage, it is considered ____________ to the antibiotic |
Susceptible |
|
|
When reading inhibition zone sizes with a ruler form a disk diffusion susceptibility test, use _____________ and ____________ to get an accurate measurement |
a dark background and reflected light |
|
|
Beta lactamases are enzymes produced by bacteria that break the beta-lactam ring of certain antibodies. When performing beta-lactamase testing using the chromogenic cephalosporin test, a positive result is indicated by... |
A deep pink color |
|
|
A disk diffusion susceptibility test is considered accurate only when... |
the purity of the organism is not in question |
|
|
The MIC will tell us... |
at what concentration visible growth of the organism in question is completely inhibited |
|
|
Microdilution antimicrobial susceptibility testing requires ____________ space than macro dilution and ________ time |
less space and less time |
|
|
If there is no ellipse present on an E-test strip and growth is up past the highest doubling dilution present on the strip, the result is read as... |
resistant |
|
|
The suspension used to inoculate a micro dilution panel must be made from a pure culture of the test organism that has been incubating... |
18-24 hours |
|
|
What are 3 things that automated antimicrobial test systems provide? |
- standardized antimicrobial concentrations - facilitation of work flow - computer-based data management systems |
|
|
What is the oxacillin agar screen test used to detect? |
Staphlyococcal resistance |
|
|
The antibiotic solution in commercially prepared micro dilution trays/panels is ___________ prior to shipment to the laboratory (3 answers) |
- frozen - freeze-dried - lyophilized |
|
|
What group determines the interpretive categories of susceptible, intermediate, or resistant for serum levels of most drug/bug combinations? |
CLSI |
|
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If the effect of combined antimicrobials is greater than the sum of the effects observed with two drugs independently, the condition is described as... |
synergism |
|
|
What does MIC stand for? |
Minimum Inhibitory Concentration |
|
|
E-test strips are best stored… |
frozen |
|
|
Which method of antimicrobial susceptibility testing uses disk diffusion methodology combined with the ability to generate MIC data? |
Epsilometer (E-Test) |
|
|
The growth and sterility wells on a broth micro dilution panel should be the _________ wells read to determine if the panel is growing appropriately prior to reviewing and recording the results of the dilutions of antimicrobial agents |
first |
|
|
What are 3 examples of beta-lactam antibiotics? |
- Penicillin - Cephalosporin - Imipenen |
|
|
The range of concentrations of antimicrobials used in MIC testing are a series of _________ dilutions |
doubling |
|
|
When combined antimicrobial drugs are clearly less effective than the most active drug alone, this condition is described as... |
antagonism |
|
|
When reading an E-Test strip result, the MIC value is read at what end of the elliptical zone? |
The narrow end where the bacteria is growing up to the strip |
|
|
Vancomycin is an agent used mainly for infections with... |
Gram-positive organisms |
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|
You are reading a micro dilution susceptibility test for E. coli. The dilutions in the ceftriaxone wells are 0.5, 1, 2, 4, 8, 16, and 32. The well with the 16 dilution has growth and the well with the 32 dilution has no growth. What is the MIC? |
32 |
|
|
You are reading an E-Test susceptibility for S. pneumoniae. The ellipse of inhibition of bacterial growth meets the penicillin gradient strip at 128g/mL. The zone interpretation ranges are: <=0.12g/mL is Susceptible 0.25-2.0g/mL is Intermediate >=4g/mL is Resistant What is the interpretation category used when reporting this susceptibility? |
Resistant |
|
|
You are reading a micro dilution susceptibility test for E. coli. The dilutions in the ceftriaxone wells are 0.5, 1, 2, 4, 8, 16, and 32. None of the wells of ceftriaxone have growth but the growth control well is growing while the sterility control well is not. What is the MIC? |
<0.5 |
|
|
You are reading an E-Test susceptibility for Streptococcus bovis. The ellipse of inhibition of bacterial growth meets the gradient strip at 1g/mL. The zone interpretation ranges are: <=1.0g/mL is Susceptible 2.0g/mL is Intermediate >=4g/mL is Resistant What interpretation category should be used when reporting susceptibility? |
Susceptible |
|
|
You are reading a Kirby-Bauer susceptibility for E.coli. The zone size around the amoxicillin/clavulanate disk is 26mm. The zone interpretation ranges are: <= 11mm is Resistant 12-15mm is Intermediate >= 16mm is Susceptible What interpretation category should be used when reporting susceptibility? |
Susceptible |
|
|
You are reading a micro dilution susceptibility test for S. aureus. The dilutions for gentamycin wells are 0.25, 0.5, 1, 2, 4, 8, and 16. The well with the 0.5 dilution has growth and the well with the 1 dilution has no growth. What is the MIC? |
1 |
|
|
You are reading a Kirby-Bauer susceptibility for S. aureus. The zone size around the erythromycin is 16mm. The zone interpretation ranges are: <= 13mm is Resistant 14-17mm is Intermediate >= 18mm is Susceptible What interpretation category should be used when reporting susceptibility? |
Intermediate |
|
|
You are reading a Kirby-Bauer susceptibility for K. pneumoniae. The zone size around the amoxicillin/clavulanate disk is 10mm. The zone interpretation ranges are: <= 11mm is Resistant 12-15mm is Intermediate >= 16mm is Susceptible What interpretation category should be used when reporting susceptibility? |
Resistant |
|
|
You are reading a Kirby-Bauer susceptibility for S. aureus. The zone size around the erythromycin is 20mm. The zone interpretation ranges are: <= 13mm is Resistant 14-17mm is Intermediate >= 18mm is Susceptible What interpretation category should be used when reporting susceptibility? |
Susceptible |
|
|
You are reading an E-Test susceptibility for Streptococcus intermedius. The ellipse of inhibition of bacterial growth meets the penicillin gradient strip at 0.5g/mL. The zone interpretation ranges are: <=0.12g/mL is Susceptible 0.25-2.0g/mL is Intermediate >=4g/mL is Resistant What is the interpretation category used when reporting this susceptibility? |
Intermediate |
|
|
STDs are caused by what types of organisms? (3 answers) |
-parasites -bacteria -viruses |
|
|
An example of a sexually transmitted parasite is... |
Pubic lice |
|
|
Sexually transmitted diseases caused by viruses _________ be cured |
cannot |
|
|
Examples of 2 viral STDs are... |
- Human Immunodeficiency Virus (HIV) - Herpes Simplex Virus (HSV or genital herpes) |
|
|
The painless, open sores of early syphillis may appear… (5 answers) |
- on the penis - around the vagina - near the mouth - near the anus - on the hands |
|
|
Gonorrhea may cause… (3 answers) |
- pelvic inflammatory disease - increased risk of ectopic pregnancy - infertility in women |
|
|
Brucella species are... |
small, gram-negative coccibacilli that are oxidase positive |
|
|
What are 3 clinical forms of anthrax? |
- cutaneous - inhalational - gastrointestinal |
|
|
Clinical Laboratorians should be vigilant for Bacillus anthraces infection, particularly among... |
mail handlers |
|
|
Bacillus anthraces growth on sheep blood agar is non-hemolytic and... |
non-motile |
|
|
If Bacillus anthraces is suspected, the laboratories should immediately contact… (3 answers) |
- The patient's healthcare provider - The state public health staff - The local public health staff |
|
|
Clinical laboratories which are the first to receive specimens that may be from a suspected case of bioterrorism have a responsibility to "Rule Out and Refer" the agent to the State Department of Health and Human Services. Those clinical laboratories are referred to as... |
A or Sentinel laboratories |
|
|
When working with a suspected Brucella species, all work should be performed in a... |
BioSafety cabinet |
|
|
Francisella tularensis organisms are tiny, pleomorphic Gram-negative rods that do not grow on MAC agar. They are oxidase ___________ and ureas __________ |
negative, negative |
|
|
Humans acquire Yersinia pestis from... |
the bite of an infected flea |
|
|
The serological test for Salmonella typhi is part of the "febrile agglutinins" panel and is individually known as the _________ test |
Widal |
|
|
The toxin of what bacteria causes botulism? |
Clostridium botulinum |
|
|
What is the cause of "Q" fever? |
Coxiella burnetii |
|
|
What is a Gram-stain description of Yersinia pestis? |
Plump, Gram-negative rods |
|
|
In cases of food borne botulism, all specimens should be sent directly to the state department of health services for testing. Those specimens could include… (3 answers) |
- stool - serum - vomit |
|
|
Smallpox disease is caused by a... |
virus |
|
|
The disease tularemia is often associated with... |
wild animals |
|
|
Yersinia pestis is the causative agent of the disease… |
plague, aka The Black Death |
|
|
What do Bacillus anthracis bacteria look like on a Gram stain? |
Large Gram-positive rods |
|
|
A DNA sequence that encodes for a specific product (RNA or protein) is defined as a... |
gene |
|
|
The most widely used target nucleic acid amplification method is the... |
Polymerase Chain Reaction (PCR) |
|
|
By using target nucleic acid amplification, a single copy of a nucleic acid target, often undetectable by standard hybridization methods, is... |
multiplied in a short period to readily detectable levels |
|
|
For all living entities, hereditary information resides or is encoded in nucleic acids. The 2 major classes include... |
DNA and RNA |
|
|
Genetic change in bacteria is accomplished by… (3 answers) |
- mutation - genetic recombination - gene exchange |
|
|
What are 2 specific examples of PCR meted derivations? |
- Multiplex PCR - Nested PCR |
|
|
__________ and _________ are 2 of the 4 criteria used by laboratories when choosing a molecular method to establish relatedness (strain typing) among the pathogens isolated during an outbreak of an infectious disease inside or outside of a hospital |
Reproducibility and Practicality |
|
|
In counterimmunoelectrophoresis, the application of an electrical current _________ migration of an antigen and antibody |
speeds up |
|
|
Latex agglutination is a ______________ procedure |
particle agglutination |
|
|
Nucleic acid hybridization assays require that one nucleic acid strand (the probe) originates form an organism of known identity and the other strand (the _______) originates from an unknown organism to be detected or identified |
target |
|
|
The latex beads used in latex agglutination and coagglutination tests have ______________ molecules bound to their surface |
antibody |
|
|
What is the bacterial agglutinin test for rickettsiae? |
Weil-Felix test |
|
|
Chromatography has 2 phases, the mobile phase and the stationary phase. The chromatographic procedures are used to separate and characterize substances based on several factors, one of which is their __________ |
size |
|
|
When performing serology testing for the detection of antibodies against an infectious agent, patients with large amounts of antibodies have ________ titers |
high |
|
|
Molecular direct detection methods for detection of microorganisms are most useful when... |
1 or 2 pathogens cause the majority of infections |
|
|
Antigens are foreign substances that elicit the production of other proteins, called antibodies, in a human or animal host. Each antigen is also called a(n)... |
antigenic determinant |
|
|
In the double immunodiffusion method of detecting soluble antigen, we are looking for visible ________ at the zone of equivalence in the agar. This method is used to confirm the presence of systemic fungi in culture by detecting their exoantigens. |
Precipitin bands |
|
|
Tuberculosis is also known as…. |
consumption |
|
|
The function of N-acetyl-L-cysteine required in the NALC-NaOH reagent for acid-fast digestion-decontamination procedures is to... |
liquefy the mucus |
|
|
Photochromogens produce pigment when... |
exposed to light for 1 hour |
|
|
5 Characteristics necessary for the identification of an isolate as Mycobacterium tuberculosis are… |
-rough -buff colony -slow growth at 37 degrees C -niacin production positive -nitrate reduction positive |
|
|
The agent used for processing specimens for mycobacterial culture contaminated with Pseudomonas is... |
Oxalic acid |
|
|
The optimal length of incubation for most mycobacterial isolates is... |
3-6 weeks |
|
|
The largest percentage of mycobacterial infections are... |
Pulmonary infections |
|
|
What specimen(s) require some sort of pretreatment prior to decontamination for AFB culture? (3 answers) |
- Gastric lavage - Urine - Stool |
|
|
For optimal recovery of mycobacteria, what minimum combination of media is required? |
1 solid and 1 liquid medium |
|
|
While examining a Kinyoun smear from a sputum concentrate, the clinical laboratory technician observes at least 4 to 5 red, beaded bacilli per oil immersion field. These results should be reported as positive for... |
Acid-fast bacilli |
|
|
The BEST medium for culture of Mycobacterium tuberculosis is... |
Lowenstein-Jensen |
|
|
Tubercule bacilli (mycobacteria) are specifically stained by... |
Kinyoun carbol fuchsin |
|
|
Mycobacterium leprae causes... |
Hansen's disease |
|
|
Susceptibility testing is required for which Mycobacterium isolate? |
M. tuberculosis |
|
|
Mycobacteria that produce pigment whether grown in the dark or the light are... |
Scotochromogens |
|
|
A bronchial washing is processed for acid-fast bacilli. What precautions should be taken to prevent infection of laboratory personnel? |
Process all specimens in a biological safety hood |
|
|
In concentration methods for acid-fast bacilli, the sputum must be... |
digested then centrifuged |
|
|
Nucleic acid probe methods have been ____________ in rapid identification of mycobacterial isolates |
successful |
|
|
Viruses will only replicate where? |
in a host cell |
|
|
Viral cell cultures must be kept ________ during icubation |
moist |
|
|
3 parts of a complete viral particle or virion |
-capsid -glycoprotein spikes -nucleic acid |
|
|
Viruses are... |
strict intracellular parasites |
|
|
Viruses can be transmitted to humans by… (4 answers) |
-person to person -contaminated needles -infected tissues -arthropod vectors |
|
|
Viruses that remain latent in host tissue can be reactivated and cause disease symptoms when... |
the host becomes immunosuppressed |
|
|
PCR tests amplify the nucleic acid of... |
a virus in question to detectable levels |
|
|
Specimens for the detection of viruses should be collected... |
as early as possible following the onset of disease |
|
|
What does Viral Transport Medium contain that prevents the overgrowth of bacteria and fungi? |
antibiotics |
|
|
Viruses are _________ than bacteria |
smaller |
|
|
The viral genome and capsid together are called... |
the nucleocapsid |
|
|
One of the ways viral serology is used is to... |
detect immune staus |
|
|
Specimens for viral isolation should be transported... |
refrigerated
|
|
|
What is used to describe the areas of dying cells in viral cell cultures which indicate presence of a virus? |
Cytopathic effect |
|
|
Shell vial culture is... |
a rapid method of conventional culture |
|
|
Processing of viral agents requires… (3 answers) |
-gloves -lab coat -BioSafety cabinet |
|
|
Direct Immunofluorescence is best used to detect __________ quantities of virus |
large |
|
|
Routine viral cell cultures are incubated for _______ weeks |
1 to 4 |
|
|
The detection of virus in ___________ is considered significant (4 answers) |
-tissue
-CSF -blood -vesicular fluid |
|
|
Why should antimicrobial susceptibility testing of normal flora isolates or isolates likely to represent contamination or colonization not be performed? |
they may encourage a clinician to treat a normal condition |
|
|
Many times, antimicrobial susceptibility testing includes drugs that are inappropriate for reporting. What should the technician do? |
A drug should not be indiscriminately reported because results may be misleading |
|
|
This is a public heath issue that is uniting scientists from across the world to develop strategies to address the issue |
Antibiotic resistance |
|
|
This is one of the first resistance mechanisms identified and is a successful strategy used by bacteria to survive the action of many classes of antibiotics. What is the resistance mechanism? |
Acquisition of inactivating enzymes |
|
|
What is the mechanism of action of the glycopeptides (vancomycin and teicoplanin)? |
the glycopeptides bind to the substrate of the transpeptidation enzyme and disrupt the cell wall construction |
|
|
What is the most critical step in any susceptibility test? |
Inoculum preparation |
|
|
Why are amino glycosides not effective treatment for meningitis? |
They do not cross the blood-brain barrier |
|
Name this image in a Lactophenol blue stain |
Penicillium spp. |
|
Name this image in a Lactophenol blue stain |
Aspergillus spp. |
|
Name this image in a Lactophenol blue stain |
Alternaria alternate |
|
|
What fluorochrome stain is used to screen for Acid-Fast bacilli? |
-Auramine rhodamine or Auramine O |
|
Name this image in an Iodine concentration 130um |
Schistosoma haemotobium egg |
|
Name this image in a trichrome stain 15um |
Giardia lamblia trophozoites |
|
Name this image in a Lactophenol blue stain |
Coccidioides immitis/posadasii (Valley Fever) |
|
Name this image in Iodine Concentrate 25um |
Enterobius vermicularis eggs |
|
Name this image in Trichrome stain 35um |
Entamoeba coli cysts |
|
|
What testing methods have enhanced the turn-around time for viral screening? (3 answers) |
-Direct Fluorescence Assay (DFA) -Cell Culture -Polymerase Chain Reaction (PCR) |
|
|
What is the role of the sentinel laboratory? |
To rule out or refer suspicious isolates |
|
|
What organism is a common cause of meningitis in neonates and infants up to 3 months of age and can be contracted passing through the birth canal? |
Streptococcus agalactiae |
|
|
What is the main symptom for primary syphillis? |
chancre |
|
|
What is usually the leading cause of death in immunocompromised patients?
|
Infections |
|
|
What is the 1st phase of biofilm production? |
Attachment |
|
|
What is the 2nd phase of biofilm production? |
Irreversible binding |
|
|
What is the 3rd phase of biofilm production? |
Thickening |
|
|
What is the 4th phase of biofilm production? |
Layering |
|
|
What is the 5th phase of biofilm production? |
Cell dispersion |
|
|
What is the most common bacterium found on the skin?
|
Coagulase-negative staphylococci |
|
|
What condition is the most likely to occur in patients with neutropenia? |
septicemia |
|
|
_________________ is a condition where there is an overgrowth of anaerobes and a decrease in lactobacilli in the vagina |
Bacterial Vaginosis |
|
|
What is bioterrorism? |
The use of bacteria, viruses, fungi, or toxins to injure people, animals, or crops to cause civil unrest |
|
|
A microbiologist is examining a blood agar plate inoculated from a patient who might have been exposed to a biological agent. It is growing a non-hemolytic, large colony with a ground glass appearance. On gram stain it is a gram positive rod with spores. It most likely may be... |
Bacillus anthracis |
|
|
Virulence factors are... |
factors that contribute to a microorganisms ability to cause harm |
|
|
The ___________ test differentiates staphylococci from streptococci |
Catalase |
|
|
How is Staphylococcus saprophytic us presumptively identified? |
Novobiocin susceptibility |
|
|
______________ is the persistent survival of microorganisms in or on the body |
Colonization |
|
|
Staphylococcus aureus and Staphylococcus progenies can both demonstrate _________ hemolysis |
beta |
|
|
Listeria are gram positive rods that... |
can cause meningitis in newborns |
|
|
_____________ and _____________ are 2 genera that are gram positive and produce spores |
Bacillus and Clostridium |
|
|
We use bacterial metabolism to help identify microorganisms. For instance some gram negative organisms may produce the enzyme urease, What does urease do?
|
catalyzes the hydrolysis of urea |
|
|
the primary reservoir for the staphylococci are...
|
nares |
|
|
What is the most common cause of death among patients with diarrhea? |
dehydration |
|
|
Hos is diarrhea usually contracted? |
contaminated food or water |
|
|
A CSF sample collected from a child yields the following results: turbid and cloudy appearance, high total protein levels, and low glucose levels What would the probable diagnosis be? |
Bacterial meningitis |
|
|
What substances do non-fermenters fail to ferment? |
Carbohydrates |
|
|
What organisms grows best at 42 degrees C and in a reduced oxygen atmosphere (5% to 10%)? |
Campylobacter jejuni |
|
|
Because urine is an excellent supportive medium for bacterial growth, how must urine specimens delayed in arriving to the laboratory be handled? |
Refrigerate and process specimen within 24 hours |
|
|
What organism is the most common cause of urinary tract infections (UTI) in humans? |
Escherichia coli |
|
|
Why can't direct microscopy be used to provide a presumptive identification of the enteric bacteria? |
The microscopic characteristics are indistinguishable from other gram-negative bacteria |
|
|
What organisms growing in a urine culture can typically be considered contaminants? |
Bacillus spp. |
|
Which immunofluorescent assay is illustrated here? |
Direct |
|
|
The physician is suspicious her patient has tuberculosis. She sends a sputum specimen to the laboratory for testing. The microbiologist determines the specimen is positive for the aura mine fluorescent stain. What confirmatory stain is performed next? (2 answers) |
-Zeihl-Neelsen -Kinyoun |
|
|
Serologic detection utilizes which human immunoglobulins to best identify a patient's disease process? |
IgG and IgM |
|
|
Most clinical laboratories use a rapid latex agglutination test to predict coagulase production in what organism? |
Staphylococcus aureus |
|
|
The rapid plasma reagin (RPR) test is considered a...
|
non-specific assay |
|
|
What test enables the presumptive identification of Crytococcus spp. from a spinal fluid specimen? |
India ink |
|
|
In the CAMP test a single streak of a beta-hemolytic streptococcus is placed perpendicular to a streak of beta-lysin-producing S. aureus. After incubation, a zone of increased lysis in the shape of an arrowhead is noted, which indicates presence of... |
Streptococcus agalactiae |
|
|
Clostridium botulinum and Clostridium tetani produce... |
spores |
|
|
A positive reaction in the hippurate hydrolysis test is evidenced by... |
the development of a blue color after addition of the ninhydrin reagent
|
|
|
Group B Streptococcus give a ______________ of hemolysis in the CAMP test |
positive arrow |
|
|
A urine culture grows Gram-positive cocci in clusters. To SPECIATE this organism, the technician should perform a coagulase test and a(n)... |
novobiacin disk test |
|
|
Colonies of Staphylococcus will grow in the presence of salt and ferment mannitol producing colonies surrounded by a ___________ halo on Mannitol Salt Agar |
Yellow |
|
|
The most critical distinction between Staphylococcus aureus and most other staphylococcus is... |
coagulase production |
|
|
The PYR test is used to aid in... |
the identification of catalase negative, Gram positive cocci |
|
|
Int eh differential staining technique (Gram stain) for bacteria, the primary stain is... |
Crystal violet |
|
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The organism Bacillus cereus would BEST be described by what Gram stain reaction? |
Gram positive rod |
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In the carbohydrate utilization test a positive reaction (yellow color) indicates what?
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acid production from the carbohydrate present in the tube |
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The aerotolerance test is used...
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to determine if an isolate thought to be an anaerobic isolate when the initial plate examination is performed is truly anaerobic |
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The gram stain procedure manual calls for acetone-alcholol decolorization for 2 minutes. The best course of action for the newly employed technician would be to...
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Ask a supervisor or trainer if this is indeed the timing to be followed |
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The importance of accurate bacterial identification cannot be overstated because identity is central to diagnostic bacteriology issues including… (4 answers) |
- determining clinical significance of a particular pathogen - guiding physician care of the patient - determining whether lab testing for detection of antimicrobial resistance is warranted - determining appropriate type of antimicrobial therapy |
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Virulence factors are... |
factors that contribute to a microorganisms ability to cause harm |
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How is Staphylococcus saprophyticus presumptively identified? |
Novobiocin susceptibility |
