Term
| What reagent is used to detect the presence of phenylalanine deaminase? |
|
Definition
|
|
Term
Voges-Proskauer = No color change
Phenylalanine = No color change
TSI = A/A, H2S; Citrate = Blue
Lysine = Yellow (Control tube - yellow)
Indole = No color change;
ONPG = Yellow
Urea = Yellow;
Motility = Positive
What is the identification? |
|
Definition
|
|
Term
| Which organism can cause "traveler's diarrhea" in developing countries? |
|
Definition
|
|
Term
| Which organism is typically MUG positive and what does a positive reaction look like? |
|
Definition
| E. coli (not E. coli 0157); fluorescence |
|
|
Term
| Which organism causes most urinary tract infections? |
|
Definition
|
|
Term
Voges-Proskauer = Pink; Phenylalanine = No color change
KIA = A/A; Citrate = Blue
Lysine = Purple (Control tube - yellow)
Indole = No color change; ONPG = Yellow
Urea = Pink; Motility = Positive
DNAse = No clearing
What is the identification? |
|
Definition
|
|
Term
Voges-Proskauer = No color change
Phenylalanine = No color change
Kligler iron agar = Yellow/yellow; Citrate = Green
Lysine = Purple (Control tube - yellow); Indole = Red
ONPG = Yellow; Urea = Yellow; Motility = Positive
What is the identification? |
|
Definition
|
|
Term
| Which of the Haemophilus species are NOT normal flora? |
|
Definition
| H. ducreyi & H. aegyptius |
|
|
Term
| Which two Haemophilus species require X and V factors for growth? |
|
Definition
| H. haemolyticus (hemolytic) & H. influenzae (nonhemolytic) |
|
|
Term
| Which two Haemophilus species require V factor for growth? |
|
Definition
| H. parahinfluenzae (nonhemolytic) & H. parahaemolyticus (hemolytic) |
|
|
Term
| Which two Haemophilus species are porphyrin test positive (fluorescence)? |
|
Definition
| H. parainfluenzae (no hemolysis present) & H. parahaemolyticus (hemolysis) |
|
|
Term
| Which organism causes pinkeye? |
|
Definition
|
|
Term
| Which organism is transmitted sexually and causes a chancroid or soft chancre? |
|
Definition
|
|
Term
| Which gram negative bacilli satellite around staphylococci on sheep blood agar? What nutrient is supplied by the staphylococci? |
|
Definition
| Haemophilus; V factor (NAD) |
|
|
Term
| Which two enteric organisms are nonmotile? |
|
Definition
|
|
Term
| Name some enterics organisms that are VP positive. |
|
Definition
| Klebsiella species, Enterobacter species & Serratia marcescens |
|
|
Term
Voges-Proskauer = Pink; Phenylalanine = No color change
TSI = A/A; Citrate = Blue
Lysine = Purple (Control tube - yellow)
Indole = No color change; ONPG = Yellow
Urea = Pink; Motility = Negative
What is the identification? |
|
Definition
|
|
Term
The technologist isolated gram negative diplococci from a sputum specimen. The following results are obtained:
CHO utilization: glucose =, maltose =, lactose =, sucrose =, nitrate +, DNAse +
What is the identification of the isolate? |
|
Definition
|
|
Term
Chromogenic substrate tests were performed on a respiratory isolate. The following results were obtained:
Hydroxyprolylaminopeptidase =
Gamma-glutamylaminopeptidase =
Beta-glactosidase =
Butyrate esterase +
What is the identification of the organism? |
|
Definition
|
|
Term
Voges-Proskauer = No color change; Phenylalanine = Green
TSI = K/A; Citrate = Green
Lysine = Yellow (Control tube - yellow); Indole = Red
ONPG = No color change; Urea = Pink; Motility = Positive
What is the identification? |
|
Definition
|
|
Term
| Which of the Neisseria species are NOT normal flora? |
|
Definition
|
|
Term
The technologist isolated gram negative diplococci from a vaginal specimen. The following results were obtained:
CHO utilization: glucose +, maltose =, lactose =, sucrose =, nitrate =, & DNAse =
What is the identification of the isolate? |
|
Definition
|
|
Term
Chromogenic substrate tests were performed on a genital isolate. The following results were obtained:
Hydroxyprolylaminopeptidase +
Gamma-glutamylaminopeptidase =
Beta-glactosidase =
Butyrate esterase =
What is the identification of the organism? |
|
Definition
|
|
Term
| Which organism causes PID (pelvic inflammatory disease)? |
|
Definition
|
|
Term
The technologist isolated gram negative diplococci from a throat specimen. The following results are obtained:
CHO utilization: glucose +, maltose +, lactose +, sucrose =, nitrate =, DNAse =
What is the identification of the isolate? |
|
Definition
|
|
Term
Chromogenic substrate tests were performed on a respiratory isolate. The following results were obtained:
Hydroxyprolylaminopeptidase +
Gamma-glutamylaminopeptidase =
Beta-glactosidase +
Butyrate esterase =
What is the identification of the organism? |
|
Definition
|
|
Term
The technologist isolated gram negative diplococci from a spinal fluid. The following results were obtained:
CHO utilization: glucose +, maltose +, lactose =, sucrose =, nitrate =, DNAse =
What is the identification of the isolate? |
|
Definition
|
|
Term
Chromogenic substrate tests were performed on a CSF isolate. The following results were obtained:
Hydroxyprolylaminopeptidase =
Gamma-glutamylaminopeptidase +
Beta-glactosidase =
Butyrate esterase =
What is the identification of the organism? |
|
Definition
|
|
Term
| Name an organism that gives a positive oxidase reaction and describe a positive reaction. |
|
Definition
| Neisseria species & M. catarrhallis are positive; dark BLUE is positive |
|
|
Term
Voges-Proskauer = No color change; Phenylalanine = Green
Triple sugar iron agar = Red/black; Citrate = Green
Lysine = Yellow (Control tube - yellow)
Indole = No color change; ONPG = No color change
Urea = Pink; Motility = Positive
What is the identification? |
|
Definition
|
|
Term
| Name three enteric organisms that are indole positive and describe a positive reaction. |
|
Definition
| Proteus vulgaris, E. coli, Klebsiella oxytoca; positive reaction is RED |
|
|
Term
Voges-Proskauer = No color change; Phenylalanine = Green
TSI = A/A, H2S; Citrate = Blue
Lysine = Yellow (Control tube - yellow); Indole = Red
ONPG = No color change; Urea = Pink; Motility = Positive
What is the identification? |
|
Definition
|
|
Term
| Name some enteric organisms that are phenylalanine deaminase positive and describe a positive reaction. |
|
Definition
| Proteus species, Providencia species, & Morganella morganii; GREEN is positive |
|
|
Term
Voges-Proskauer = No color change; Phenylalanine = Green
TSI = Red/yellow; Citrate = Blue
Lysine = Yellow (Control tube - yellow); Indole = Red
ONPG = No color change; Urea = Pink; Motility = Positive
What is the identification? |
|
Definition
|
|
Term
| What three organisms give different reactions on the TSI & KIA? |
|
Definition
| S. marcescens, Y. enterocolitica & P. vulgaris |
|
|
Term
| Which enteric pathogens isolated from stool are urea negative? |
|
Definition
| Salmonella & Shigella (Edwardsiella is rarely isolated) |
|
|
Term
| Which two enteric pathogens produce lactose negative colonies on EMB and what is the expected appearance of the organisms? |
|
Definition
| Salmonella & Shigella are lactose negative & produce colorless colonies |
|
|
Term
| Name three enteric organisms that are citrate positive and describe a positive reaction. (There are more that three enterics that are citrate + but the citrate reaction is a key identifying reaction for three of the organisms.) |
|
Definition
| Salmonella, Citrobacter & Providencia; BLUE is positive |
|
|
Term
Which organisms produce the following KIA reaction?
K/A, H2S |
|
Definition
| Salmonella, Proteus, & Citrobacter |
|
|
Term
| Which organisms cause diarrhea? |
|
Definition
| Salmonella, Shigella, Yersinia enterocolitica, & Edwardsiella |
|
|
Term
Voges-Proskauer = No color change
Phenylalanine = No color change
TSI = Red/black; Citrate = Blue
Lysine = Purple (Control tube - yellow)
Indole = No color change; ONPG = No color change
Urea = Yellow; Motility = Positive
What is the identification? |
|
Definition
|
|
Term
| Which organism and disease are associated with "rose spots"? What are "rose spots"? |
|
Definition
| Salmonella Typhi; typhoid fever; red lesions on the abdomen |
|
|
Term
Voges-Proskauer = Pink; Phenylalanine = No color change
KIA = Red/yellow; Citrate = Blue
Lysine = Purple (Control tube - yellow); Indole = No color change
ONPG = Yellow; Urea = Yellow
DNAse = Clearing; Motility = Positive
What is the identification? |
|
Definition
|
|
Term
| Which enteric organism is DNAse positive & what does a positive reaction look like? |
|
Definition
| Serratia marcescens; clearing of medium |
|
|
Term
| Which organism is unable to decarboxylate or deaminate lysine & what is the expected LIA result? |
|
Definition
| Shigella = K/A (purple/yellow) |
|
|
Term
Voges-Proskauer = No color change
Phenylalanine = No color change
Kligler iron agar = K/A; Citrate = Green
Lysine = Yellow (Control tube - yellow)
Indole = No color change; ONPG = No color change
Urea = Yellow; Motility = Negative
What is the identification? |
|
Definition
|
|
Term
| Which organism is spread by 4 Fs and what are the 4 Fs? |
|
Definition
| Shigella; food, feces, fingers, & flies |
|
|
Term
| Which organism causes plague? |
|
Definition
|
|
Term
| Which organisms decarboxylate lysine & what are the expected LIA results? |
|
Definition
| E. coli = K/K (purple/purple) & Salmonella = K/K, H2S (purple/purple, H2S) |
|
|
Term
| Which organisms can causes hemolytic uremic syndrome (HUS) and hemorrhagic colitis? |
|
Definition
| Enterohemorrhagic E. coli strains, including E. coli 0157:H7 |
|
|
Term
| Which organism deaminates lysine & what is the expected LIA result? |
|
Definition
|
|
Term
| Which organism can cause a disease that mimics appendicitis? |
|
Definition
|
|
Term
| How are enterohemorrhagic E. coli strains detected? |
|
Definition
| By detecting Shiga-toxins using PCR, EIA, or cytotoxicity assay |
|
|
Term
| What is the correct atmosphere for incubating Neisseria gonorrhoeae and Neisseria meningitidis. |
|
Definition
|
|
Term
True or False:
All lactose negative organisms on enteric plate media such as EMB will give a negative reaction on the ONPG test. |
|
Definition
| False; some lactose negative organisms are slow lactose fermenters |
|
|
Term
| Which tube media detects H2S? |
|
Definition
|
|
Term
| Shigella spp. may belong to one of four serogroups. What are they? |
|
Definition
| A (S. dysenteriae), B (S. flexneri), C (S. boydii), & D (S. sonnei)) |
|
|
Term
| What does the VP test detect? |
|
Definition
|
|
Term
| When reading the lysine decarboxylase test at 12 hours both the test and control tubes are yellow. How should these results be interpreted? |
|
Definition
| Acid is produced when the MO uses glucose; reincubate for at least 6 more hours |
|
|
Term
| What reagents are used for the Voges-Proskauer test? |
|
Definition
|
|
Term
| What endproduct is produced when urease breaks down urea? |
|
Definition
|
|
Term
| Which culture media supports the growth of Neisseria meningitidis? |
|
Definition
| BAP, CHOC, & selective media (MTM, ML, NYC, GLC) |
|
|
Term
| Which enzyme breaks down lactose into glucose & galactose? |
|
Definition
|
|
Term
| The substrate in the MUG test is broken down by _____________ to form 4-methylumbelliferone. |
|
Definition
|
|
Term
| What media should be set-up for GC request on joint fluid culture? |
|
Definition
| Blood agar & chocolate agar |
|
|
Term
| What media should be set-up for GC request on genital culture? |
|
Definition
| Blood agar & selective GC agar |
|
|
Term
| Name two plate media used to isolate Salmonella only. |
|
Definition
| Brilliant green agar & bismuth sulfite agar |
|
|
Term
| How are mixed acids detected in the MR test? |
|
Definition
| By pH indicator, methyl red |
|
|
Term
| Lysine decarboxylase degrades lysine to form ___________. |
|
Definition
|
|
Term
| Which culture media supports the growth of Neisseria gonorrhoeae? |
|
Definition
| CHOC, & selective media (MTM, ML, NYC, or GLC) |
|
|
Term
| What medium is used to isolate Yersinia enterocolitica, at what temperature is the plate incubated, and what do the colonies look like? |
|
Definition
| CIN; incubate at room temperature, bull's eyes (red center & clear edges) |
|
|
Term
| What is the correct atmosphere for incubating TSA or MH agar inoculated with suspected Haemophilus with X & V strips? |
|
Definition
|
|
Term
| An organism produces blue-green colonies w/ black centers on HE agar. What is the expected appearance of this organism on MAC agar? |
|
Definition
|
|
Term
| An organism produces red colonies on XLD agar. What is the expected appearance of this organism on EMB agar? |
|
Definition
|
|
Term
| Gram negative diplococci was isolated from a genital culture of a 11 year old girl. Using carbohydrate utilization tests the organism was identified as N. gonorrhoeae. The technologist should: |
|
Definition
| Confirm the identication using another test method other than molecular tests. |
|
|
Term
| When reading the lysine decarboxylase test at 18 hours the test tube is purple and control tube is yellow. How should these results be interpreted? |
|
Definition
| Control result correct; MO decarboxylates lysine |
|
|
Term
| What is the purpose of using the LIA? |
|
Definition
| Detect Salmonella from stool specimens |
|
|
Term
| What is the principle of the citrate test? |
|
Definition
| Detemines if MOs can use citrate as carbon source |
|
|
Term
| What processes are detected by the LIA? |
|
Definition
| Determines whether MO decarboxylates or deaminates lysine, H2S production |
|
|
Term
| What do aerogenic enterics produce? |
|
Definition
| GAS; anaerogenic enterics don't produce gas in KIA, TSI, & LIA |
|
|
Term
What sugars are being fermented in the following KIA reaction and which organisms produce this result?
A/A (acid/acid; yellow/yellow) |
|
Definition
| Glucose & lactose are fermented; E. coli, Klebsiella & Enterobacter |
|
|
Term
What sugars are being fermented in the following KIA reaction and which organisms produce the following result?
KIA = K/A (alkaline/acid; red/yellow) |
|
Definition
| Glucose is fermented; Shigella, Providencia & Morganella |
|
|
Term
| What is the appearance of H. ducreyi on Gram stain? |
|
Definition
| Gram negative bacilli in "school of fish" morphology |
|
|
Term
| How is hemolysis detected for Haemophilus species? |
|
Definition
| Growth on horse or rabbit blood or satellite test on sheep blood agar |
|
|
Term
| What three tests are detected by SIM medium? |
|
Definition
| H2S production; indole; & motility |
|
|
Term
| What endproduct is produced when tryphanase breaks down tryptophan? |
|
Definition
|
|
Term
| What test is used to separate Klebsiella pneumoniae from K. oxytoca? |
|
Definition
|
|
Term
| Should chocolate agar be used to detect X & V growth requirements for Haemophilus isolates? Why or why not. |
|
Definition
| It isn't used because it contains both X & V factors. |
|
|
Term
| How do the KIA & TSI tests differ? |
|
Definition
| KIA detects glucose & lactose fermentation; in addition TSI detects sucrose |
|
|
Term
| Which tests must be read at 18-24 hours? |
|
Definition
| KIA, TSI, LIA, & lysine decarboxylase |
|
|
Term
| What is used to detect porphobilinogen in the porphyrin test? |
|
Definition
| Kovac's reagent (para-dimethylaminobenzaldehyde) |
|
|
Term
| What sugar is found in all the enteric plate media? |
|
Definition
|
|
Term
| Is K. pneumonia indole positive or negative? |
|
Definition
|
|
Term
| Is K. oxytoca indole positive or negative? |
|
Definition
|
|
Term
| What is the next step in identifying Salmonella or Shigella isolates if serogrouping fails to produce agglutination? |
|
Definition
| Make suspension of isolate, heat to remove capsular AGN, & retest isolate |
|
|
Term
| What does the MR test detect? |
|
Definition
|
|
Term
| Since Salmonella ferments xylose, why isn't it yellow in XLD? |
|
Definition
| MO produces an alkaline enviroment when it metabolizes lysine |
|
|
Term
| The 12 hour result for the LIA test are K/A (purple/yellow). How should these results be interpreted? |
|
Definition
| MO uses glucose & produces acid in butt of tube; reincubated for 6 more hours |
|
|
Term
| A direct gram stain of a urethral discharge showing intracellular gram negative diplococci is diagnostic for Neisseria gonorrhoeae. Would the same be true for endocervical specimens? |
|
Definition
| No - females possess normal genital flora that can mimic GC on gram stain |
|
|
Term
What sugars are being fermented in the following KIA reaction and which organisms produce this result?
K/K or K/NC |
|
Definition
| No sugars are used; MOs use peptones; Pseudomonas & Acinetobacter |
|
|
Term
Is the following lysine decarboxylase test performed correctly:
1) Inoculate test tube and control tube with MO
2) Cover the test tube with sterile mineral oil
3) Read at 18-24 hours |
|
Definition
| NO; both the test and control tubes should overlayed w/ sterile oil |
|
|
Term
| Is XLD typically used to isolate pathogens from specimens such as urine or wounds? |
|
Definition
| NO; EMB or MAC would be used; XLD, SS & HE are used for stools only |
|
|
Term
What produces the red result in the following KIA reaction?
Red/yellow |
|
Definition
| Non-lactose fermentor uses peptones & produces alkaline enviroment |
|
|
Term
| What is the most sensitive method for detecting Neisseria gonorrhoeae from patient specimens? |
|
Definition
| Nucleic acid amplification tests (NAAT) |
|
|
Term
| Identification of Salmonella and Shigella includes biochemical testing and serogrouping procedures. Which antigens are detected and where are they located? |
|
Definition
| O in cell wall; H in flagella; & K & VI in capsule |
|
|
Term
| How long is the expiration date for a newly opened oxidase ampule? |
|
Definition
| One day - new reagent has to be opened daily |
|
|
Term
Can the following specimens be gram stained to detect GC?
Throat swab
Rectal swab
Genital specimens |
|
Definition
| Only the genital specimens can be gram stained to examine for GC |
|
|
Term
| The technologist isolates a gram negative diplococci from a respiratory culture. What test should he/she perform before setting up carbohydrate tests or chromogenic substrate tests? |
|
Definition
|
|
Term
| What three characteristics are common to enterics? |
|
Definition
| Oxidase = (except Plesiomonas), glucose fermented, & nitrate + (almost all) |
|
|
Term
| What reagent is used for the indole test? |
|
Definition
| Para-dimethylaminobenzaldehyde; found in Kovac & Ehrlich reagents |
|
|
Term
| What type of media should be used when performing the oxidase test? |
|
Definition
| Perform test off of BA or CHOC; differential media can give false results |
|
|
Term
| Which enzyme is responsible for transporting lactose into the bacterial cell? |
|
Definition
|
|
Term
| What two enzymes are responsible for utlization of lactose? |
|
Definition
| Permease & ß-galactosidase |
|
|
Term
| The phenylalanine test detects a deaminase that breaks down phenylalanine to form ______________ _____. |
|
Definition
|
|
Term
| An organism produces pink colonies with precipitated bile on MAC agar. What is the expected appearance of this organism on SS? |
|
Definition
|
|
Term
| Ornithine decarboxylase degrades ornithine to __________. |
|
Definition
|
|
Term
| Two enzymes, dihydrolase & decarboxylase, degrade arginine to _________. |
|
Definition
|
|
Term
| An organism produces colorless colonies w/ black centers on SS agar. What is the expected appearance of this organism on XLD? |
|
Definition
| Red colonies w/ black centers |
|
|
Term
| Describe the positive reactions for VP & MR tests. |
|
Definition
|
|
Term
| What color is a positive urease test? |
|
Definition
|
|
Term
| What is the characteristic pigment of Serratia marcescens on media? |
|
Definition
|
|
Term
| What do lactose positive organisms look like on MAC and SS agar? |
|
Definition
| Red/pink; also pink precipitate (bile) on MAC |
|
|
Term
| Name two enrichment broths used to isolate Salmonella and Shigella. |
|
Definition
| Selenite (primarily for Salmonella) & Gram-negative broth (GN) |
|
|
Term
| What population is at risk for Shigella infections? |
|
Definition
|
|
Term
| What medium is used to isolate E. coli 0157 and what do the colonies look like? |
|
Definition
| Sorbitol-MacConkey (SMAC); colonies are colorless because MO can't use sorbitol |
|
|
Term
| Which enteric plate media detects H2S? |
|
Definition
|
|
Term
| What should be used to transfer colonies to filter paper when performing the oxidase test from agar plates? |
|
Definition
| Sterile stick or platinum loop |
|
|
Term
| What is the characteristic growth of Proteus on blood agar? |
|
Definition
|
|
Term
The technologist performed chromogenic substrate tests on a gram negative diplococci from a genital specimen. It was set-up on MTM & CHOC. The tests were performed from growth on the CHOC and were as follows:
Hydroxyprolylaminopeptidase +
Gamma-glutamylaminopeptidase =
Beta-glactosidase =
Butyrate esterase =
What is the identification of the organism? |
|
Definition
| Tests are invalid. Tests MUST be performed from gonoccoccal selective media. |
|
|
Term
| What reagent is used for the oxidase test? |
|
Definition
| Tetramethyl-para-phenylenediamine |
|
|
Term
| Why does Y. enterocolitica give different results on KIA (K/A) & TSI (A/A)? |
|
Definition
| The MO doesn't ferment lactose in KIA but does ferment sucose in TSI |
|
|
Term
| Which is the most important Haemophilus serotype? |
|
Definition
| Type b; Hib vaccine prevents infections by serotype b |
|
|
Term
| What are the urease and motility tests results for Yersinia enterocolitica? |
|
Definition
| Urease positive; motility positive at 25 C & negative at 35 C |
|
|
Term
| What is the characteristic appearance of Klebsiella on media? |
|
Definition
|
|
Term
| What is used to detect porphyrins in the porphyrin test? |
|
Definition
| Wood's lamp (fluoresce reddish-orange) |
|
|
Term
| What identification tests can be performed on a pleomorphic GNB that only grows on chocolate agar (no growth on blood agar and MAC)? |
|
Definition
| X & V strips/disks or porphyrin test & hemolysis check |
|
|
Term
| What growth factors are required for growth of Haemophilus species? |
|
Definition
|
|
Term
| What components are included in the Quad plate for identification of Haemophilus? |
|
Definition
| X, V, XV, & horse blood for detection of hemolysis |
|
|
Term
| An organism produces metallic green sheen colonies on EMB agar. What is the expected appearance of this organism on HE? |
|
Definition
|
|
Term
Are the following specimens cceptable for isolation of GC?
Throat swab
Rectal swab
Genital specimens |
|
Definition
| Yes, all can be cultured for GC |
|
|
Term
| Which enzyme cleaves lactose into glucose & galactose? |
|
Definition
|
|
Term
| What enzyme is detected when using the ONPG test and what does a positive reaction look like? |
|
Definition
| ß-galactosidase is detected & a positive reaction is YELLOW |
|
|
