Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
154 Cards in this Set
- Front
- Back
|
Staphylococcus aureus causes what diseases?
|
food poisoning, pneumonia, osteomyelitis, endocarditis, wound infections, scalded skin syndrome, toxic shock syndrome
|
|
|
Staphylococcus aureus is usually _____ hemolytic on SBA
|
beta
|
|
|
The S. aureus latex agglutination test detects what on the surface of the bacterium?
|
clumping factor and protein A
|
|
|
S. aureus is PYR ______ and ornithine ______.
|
PYR negative, ornithine negative
|
|
|
(T/F) Staphylococci can tolerate the high salt concentration (7.5%) of mannitol salt agar.
|
True
|
|
|
S. aureus produces what color colonies on mannitol salt agar?
|
Yellow, it can ferment mannitol
|
|
|
Staphylococci other than S. aureus are what color on MSA?
|
Red, they cannot ferment mannitol
|
|
|
(T/F) S. aureus is typically resistant to penicillin
|
True, it forms beta-lactamase
|
|
|
(T/F) Coagulase negative staphylococci are very common skin flora
|
True, they are usually nonpathogenic except in immunosuppressed and neutropenic patients
|
|
|
Staphylococcus epidermidis is novobiocin _________.
|
susceptible
|
|
|
S. saprophyticus is novobiocin ___________.
|
resistant
|
|
|
Micrococcus appears as _______ on gram stains
|
gram positive tetrads
|
|
|
Group A streptococci typically cause what infections?
|
strep throat, impetigo, scarlet fever, pneumonia, otitis media, necrotizing fasciitis
|
|
|
What are two sequelae caused by S. pyogenes?
|
glomerulonephritis, rheumatic fever
|
|
|
S. pyogenes is sensitive to ________.
|
bacitracin
|
|
|
S. pyogenes is PYR _______.
|
positive
|
|
|
S. pyogenes appear how on SBA?
|
pinpoint colonies with large zones of beta hemolysis
|
|
|
Micrococci are bacitracin ____ while staphylococci are bacitracin ______.
|
Micrococci are bacitracin sensitive, staphylococci are bacitracin resistant
|
|
|
________ causes the rash seen in scarlet fever.
|
Streptococcal pyrogenic exotoxin (erythrogenic toxin) of S. pyogenes
|
|
|
Streptolysin O and Streptolysin S do what?
|
lyse erythrocytes, platelets and neutrophils
|
|
|
Group B Streptococcus/S. agalactiae usually causes what infection?
|
Early onset neonatal sepsis and meningitis. Can also cause postpartum fever, osteomyelitis, and wound infections.
|
|
|
Group B Streptococcus/S. agalactiae is _______ hemolytic
|
beta
|
|
|
Group B Streptococcus/S. agalactiae is CAMP __________.
|
positive
|
|
|
Group B Streptococcus/S. agalactiae is hippurate _______ and PYR ________.
|
hippurate positive, PYR negative
|
|
|
Group B Streptococcus/S. agalactiae is _______ to bacitracin and ________ to SXT.
|
resistant to bacitracin, resistant to SXT
|
|
|
Group D streptococci are _____ hemolytic
|
beta or gamma
|
|
|
Group D streptococci are bile esculin ______, PYR _______ and ______ for growth in 6.5% NaCl.
|
bile esculin positive, PYR negative, negative for growth in 6.5% NaCl
|
|
|
Viridans streptococci cause what type of infections?
|
endocarditis, wound infections and brain abcesses
|
|
|
Viridans streptococci are _____ hemolytic
|
alpha
|
|
|
Viridans streptococci are bile _______ and optochin _______.
|
bile insoluble, optochin resistant
|
|
|
S. pneumoniae is normal flora in ______.
|
the upper respiratory tract
|
|
|
S. pneumoniae causes what types of infection?
|
Lobar pneumonia in elderly and alcoholics (community acquired), otitis media in infants and children, meningitis in children
|
|
|
S. pneumoniae appears how in gram stain?
|
gram positive lancet or bullet shaped diplococci
|
|
|
S. pneumonia is ____ hemolytic
|
alpha
|
|
|
Colony morphology of S. pneumoniae
|
Mucoid, umbilicated/depressed centers
|
|
|
S. pneumoniae is optochin _______ and bile _______.
|
optochin sensitive, bile soluble
|
|
|
Enterococcus is bile-esculin _______, PYR _______ and _______ for growth in 6.5% NaCl.
|
bile-escullin positive, PYR positive, positive for growth in 6.5% NaCl
|
|
|
Enterococcus exhibits what lancefield group antigen?
|
D
|
|
|
What type of hemolysis does a group D streptococcus exhibit?
|
Can be gamma or beta. Usually gamma.
|
|
|
Listeria monocytogenes typically causes infection in what population?
|
Pregnant women, neonates, immunosuppressed patients
|
|
|
What is the most common infection associated with L. monocytogenes?
|
Meningitis
|
|
|
L. monocytogenes is typically transmitted in what product?
|
unpasteurized dairy
|
|
|
L. monocytogenes exhibits a ____ zone of ____ hemolysis on SBA.
|
narrow, beta
|
|
|
L. monocytogenes exhibits what type of motility in semisolid media?
|
umbrella
|
|
|
L. monocytogenes exhibits what type of motility in wet mount?
|
tumbling
|
|
|
L. monocytogenes is hippurate _____, CAMP ______, esculin ______ and catalase ______.
|
positive for all
|
|
|
Corynebacterium diptheriae causes what disease? What symptom is characteristic of this disease?
|
Diptheria, pseudomembrane at the back of the throat (dead cells/exudate)
|
|
|
Describe the appearance of C. diphtheriae on gram stain
|
pleomorphic with picket fence or Chinese letter formations
|
|
|
Staining C. diphtheriae with methylene blue will reveal what feature?
|
Metachromatic granules which are red to purple intracellular granules
|
|
|
C. diphtheriae is urease ______, nitrate _____, motility _____ and catalase ______.
|
urease negative, nitrate positive, motility negative, catalase positive
|
|
|
What test is used to determine toxin production by C. diphtheriae?
|
The Elek test uses antitoxin to detect toxin production
|
|
|
What media are used for C. diphtheriae?
|
Cystine-tellurite, Tinsdale's agar, Loeffler agar
|
|
|
Appearance of C. diphtheriae on cystine-tellurite
|
black colonies due to hydrolysis of tellurite
|
|
|
Appearance of C. diphtheriae on Tinsdale's agar
|
brown to black colonies with halos from hydrolysis of tellurite
|
|
|
Appearance of C. diphtheriae on Loeffler agar
|
small white to gray colonies, enhances pleomorphism and formation of metachromatic granules for methylene blue stain
|
|
|
Corynebacterium urealyticum causes what type of infection?
|
UTI
|
|
|
C. urealyticum is urease _____.
|
positive
|
|
|
Erysipelothrix rhusiopathiae typically causes infection after contact with what?
|
animals (usually occupational exposure)
|
|
|
Nocardia asteroides is generally found in what type of patient?
|
Immunocompromised patients with chronic pulmonary disorders
|
|
|
Nocardia asteroides is catalase ____ and ____ for motility
|
catalase positive, negative for motility
|
|
|
Nocardia asteroides appears how on staining?
|
partially acid fast, pleomorphic, branching, gram positive bacillus, beading arrangement
|
|
|
The exudate of a Nocardia asteroides infection contains what?
|
masses of filamentous organisms with pus that resemble sulfur granules
|
|
|
How does an individual contract pulmonary anthrax?
|
Inhalation of spores from sheep's wool, known as "wool sorter's disease"
|
|
|
Describe the appearance of B. anthracis colonies
|
Medusa-head colonies, nonhemolytic with filamentous projections
|
|
|
B. cereus typically causes what in healthy individuals?
|
Food poisoning and occasionally wound infection
|
|
|
Describe the colony morphology of B. cereus
|
Large, flat, beta-hemolytic colonies with irregular edges
|
|
|
(T/F) B. cereus is motile
|
True
|
|
|
B. cereus is ____ to penicillin
|
resistant
|
|
|
(T/F). N. gonorrhoeae will grow on SBA
|
False, it is fastidious and requires enriched media such as chocolate agar.
|
|
|
Selective media for N. gonorrhoeae
|
Thayer-Martin, Martin-Lewis, NYC and GC-Lect agars
|
|
|
What type of atmosphere does N. gonorrhoeae require
|
increased CO2 with humidified atmosphere
|
|
|
N. gonorrhoeae colonies appear ________ on chocolate agar
|
Flat, smooth, glistening, gray or tan
|
|
|
N. gonorrhoeae is catalase ____, oxidase _____,and DNase _______.
|
catalase positive, oxidase positive, DNase negative
|
|
|
N. gonorrhoeae is nitrate ______.
|
negative
|
|
|
N. gonorrhoeae utilizes what sugars?
|
Glucose only. (not maltose, lactose or sucrose)
|
|
|
N. meningitidis causes what?
|
Meningitis, septicemia, DIC, Waterhouse-Friderichsen syndrome
|
|
|
N. meningitidis is catalase ____, oxidase ____, DNase ____ and nitrate _____.
|
catalase positive, oxidase positive, DNase negative, nitrate negative
|
|
|
N. meningitis utilizes what sugars?
|
Glucose and maltose only (not lactose or sucrose)
|
|
|
N. meningitidis will produce what type of colonies on SBA in increased CO2?
|
bluish-gray colonies
|
|
|
Moraxella catarrhalis causes what types of infection?
|
otitis media, sinusitis
|
|
|
Moraxella is catalase ______, oxidase ______, DNase ______ and nitrate _____.
|
positive for all
|
|
|
Moraxella uses what sugars?
|
None, it is asaccharolytic
|
|
|
Main characteristics of Enterobacteriaceae
|
Facultative anaerobes, ferment glucose, nitrate reducers, catalase positive, oxidase negative, usually motile (except Shigella, Klebsiella)
|
|
|
Describe the appearance of Salmonella and Shigella on Salmonella-Shigella agar
|
Lactose fermenters produce red colonies; Salmonella colonies are colorless with black centers, Shigella colonies are colorless
|
|
|
E. coli appearance in TSI
|
A/A, H2S negative
|
|
|
Describe the appearance of E. coli on MAC
|
pink/red colonies
|
|
|
E. coli is usually _____ hemolytic on SBA
|
beta
|
|
|
IMViC results for E. coli
|
++--
|
|
|
ONPG result for E. coli
|
positive
|
|
|
(T/F) E. coli is motile
|
True
|
|
|
Urease result for E. coli
|
negative
|
|
|
Appearance of E. coli O157:H7 on sorbitol-MacConkey
|
Colonies appear colorless because this strain does not ferment sorbitol; other strains of E. coli will appear pink due to sorbitol fermentation
|
|
|
ETEC causes what?
|
Enterotoxigenic E. coli produces severe epidemic diarrhea, mainly from drinking contaminated water
Traveler's diarrhea |
|
|
TSI result for Shigella
|
K/A, no H2S, no gas
|
|
|
Methyl Red result for Shigella
|
positive
|
|
|
Urease result for Shigella
|
negative
|
|
|
Citrate result for Shigella
|
negative
|
|
|
Motility result for Shigella
|
negative
|
|
|
Klebsiella species typically cause what infections?
|
UTIs and pneumonia
|
|
|
TSI result for Klebsiella pneumoniae
|
A/A with gas, no H2S
|
|
|
Appearance of Klebsiella pneumoniae on MAC
|
mucoid and very pink
|
|
|
Motility result for Klebsiella
|
negative
|
|
|
MR result for Klebsiella spp.
|
negative
|
|
|
Indole result for K. oxytoca
|
positive
|
|
|
Indole result for K. pneumoniae
|
negative
|
|
|
Klebsiella is VP _______ and citrate _______.
|
positive for both
|
|
|
(T/F) Klebsiella is a lactose fermenter
|
True
|
|
|
Infections caused by Enterobacter
|
respiratory tract infections, wounds, blood
|
|
|
IMViC results for Enterobacter
|
--++
|
|
|
Serratia typically causes what type of infection?
|
Opportunistic in patients who are immunosuppressed
|
|
|
DNase, gelatinase and lipase are characteristically positive in which enteric species?
|
Serratia marcescens
|
|
|
Serratia marcescens produces a characteristic ____ pigment
|
red
|
|
|
Serratia is VP _______ and citrate ________.
|
positive for both
|
|
|
How is Salmonella transmitted?
|
Animal reservoirs permit transmission through undercooked food (especially chicken) and contaminated water
|
|
|
Salmonella is H2S ______, citrate ______ and indole ______.
|
H2S positive
Citrate positive Indole negative |
|
|
Urease result for Salmonella
|
negative
|
|
|
Is Salmonella a lactose fermenter?
|
No
|
|
|
Appearance of Salmonella on HE agar
|
Green with black centers
|
|
|
H2S result for Proteus
|
positive
|
|
|
Typical colony morphology of Proteus
|
swarming
|
|
|
Urease result for Proteus
|
positive
|
|
|
Proteus is tryptophan deaminase _____ and phenylalanine deaminase _______.
|
positive for both
|
|
|
ONPG result for Proteus
|
negative
|
|
|
How do you differentiate P. vulgaris from P. mirabilis?
|
Indole is positive for vulgaris and negative for mirabilis
|
|
|
Yersinia pestis causes what? How is it transmitted?
|
Plague, transmitted by fleas of small rodents, endemic to the U.S. southwest
|
|
|
Yersinia enterocolitica is ONPG _______. It typically appears ______ on MacConkey at 18 hours. TSI result for this organism is _______.
|
positive, colorless, A/A. This is because this organism is a delayed lactose fermenter.
|
|
|
Microscopic appearance of Yersinia
|
small gram-negative coccobacilli
|
|
|
What is CIN agar?
|
Cefsulodin-irgasan-novobiocin medium, it is selective and differential for Yersinia enterocolitica (bullseye apperance). Aeromonas will also grow on this medium.
|
|
|
Yersinia pestis is typically motile. (T/F)
|
False, Yersinia pestis is nonmotile at both 25 and 37 degrees Celsius
|
|
|
Y. pestis is catalase ______, oxidase _____ and urease ______.
|
catalase positive, oxidase negative, urease negative.
|
|
|
Edwardsiella is H2S ______ and ONPG _______.
|
H2S positive, ONPG negative
|
|
|
E. tarda is indole ____ and citrate ______.
|
indole positive
citrate negative |
|
|
Citrobacter freundii resembles E. coli on MAC but can be differentiated because it is H2S ____ and indole ____.
|
H2S positive, indole negative
|
|
|
Morganella is indole _____, VP _____ and citrate _____.
|
indole positive, VP negative, citrate negative
|
|
|
PDA and TDA results for Providencia
|
positive for both
|
|
|
Providencia is indole ______, citrate ______ and VP _____.
|
indole positive
citrate positive VP negative |
|
|
(T/F) HACEK organisms are fastidious
|
True
|
|
|
H. influenzae causes what infections?
|
Meningitis in children, respiratory tract infections, acute sinusitis, chronic bronchitis, pneumonia
|
|
|
(T/F) H. influenzae should be tested for beta-lactamase
|
True, it may be penicillin resistant
|
|
|
Haemophilus ducreyi causes what infections?
|
Genital ulcers, chancroids and buboes
|
|
|
H. influenzae requires what growth factors? What hemolytic pattern does it display?
|
X and V, non-hemolytic
|
|
|
H. ducreyi requires what growth factors? What hemolytic pattern does it display?
|
X factor only, non-hemolytic
|
|
|
H. aphrophilus requires what growth factors? What hemolytic pattern does it display?
|
None, non-hemolytic
|
|
|
H. haemolyticus requires what growth factors? What hemolytic pattern does it display?
|
X and V factor, beta hemolytic
|
|
|
H. parainfluenzae requires what growth factors? What hemolytic pattern does it display?
|
V factor only; non-hemolytic
|
|
|
H. paraphrophilus requires what growth factors? What hemolytic pattern does it display?
|
V only, non-hemolytic
|
|
|
What infections does P. aeruginosa cause?
|
Burn wound infections, eye infections, ear infections, lower respiratory tract infections in CF patients, nosocomial infections in immunosuppressed patients
|
|
|
(T/F) Pseudomonas aeruginosa is a lactose fermenter
|
False, Pseudomonas is a nonfermentative organism
|
|
|
Colony morphology of P. aeruginosa
|
Large, irregular colonies with a grapelike odor and metallic sheen on SBA. Beta-hemolytic. Blue-green color due to pyoverdin and pyocyanin.
|
|
|
Result of P. aeruginosa in the oxidative-fermentative glucose test
|
Yellow (acid) in the open (oxidative) tube.
Green (no change) in the closed (fermentative) tube. |
|
|
Acinetobacter is motility _____, oxidase ______, nitrate ______, and catalase ______. (identifying characteristics)
|
motility negative
oxidase negative nitrate negative catalase positive |
|
|
Preferred agars for Bordetella pertussis
|
Bordet-Gengou (potato infusion), Regan-Lowe (charcoal-hose blood agar)
|
|
|
Bordetella pertussis colonies appear like ______ and are ______ hemolytic.
|
mercury droplets, beta
|
|
|
Bordetella pertussis can be differentiated from other Bordetella species by its negative ____ result. All other species are positive.
|
urease
|
