Enterobacterales Part 2

*Question: Which carbapenemase is found in Klebsiella, Enterobacter, and now Serratia marcescens?
A) VIM
B) IMP
C) KPC
D) NDM-1

*Answer: C) KPC

*Question: What does KPC stand for?
A) Klebsiella Pneumoniae Capsule
B) Klebsiella Pneumoniae Carbapenemase
C) Kinetic Protein Complex
D) Kidney Protein Carrier

*Answer: B) Klebsiella Pneumoniae Carbapenemase

*Question: What diagnostic tool uses real-time multiplex PCR to detect five carbapenemase genes?
A) VITEK system
B) Xpert Carba-R Assay
C) MALDI-TOF MS
D) Etest

*Answer: B) Xpert Carba-R Assay

*Question: Which three are metallo-β-lactamases of global concern?
A) KPC, OXA, CTX-M
B) VIM, IMP, NDM-1
C) TEM, SHV, CMY
D) AmpC, OXA, PER

*Answer: B) VIM, IMP, NDM-1

*Question: What is the primary marker used for fecal contamination in water quality testing?
A) Enterococcus
B) Salmonella
C) Escherichia coli
D) Klebsiella

*Answer: C) Escherichia coli

*Question: Which E. coli adhesin has affinity for the Dr blood group system?
A) P fimbriae
B) Type 1 pili
C) Afa/Dr adhesins
D) Bundle-forming pili

*Answer: C) Afa/Dr adhesins

*Question: Which E. coli adhesin attaches to P blood group antigens?
A) Type 1 pili
B) P fimbriae
C) Type IV pili
D) Curli

*Answer: B) P fimbriae

*Question: What is UPEC?
A) Uropathogenic E. coli with type 1 pili
B) Urease-Producing E. coli
C) Ultra-Pathogenic E. coli
D) Urea-Positive E. coli

*Answer: A) Uropathogenic E. coli with type 1 pili

*Question: What is NMEC?
A) Non-Motile E. coli
B) Neonatal Meningitis E. coli (E. coli K1)
C) Non-Mucoid E. coli
D) Necrotizing Meningeal E. coli

*Answer: B) Neonatal Meningitis E. coli (E. coli K1)

*Question: What is the adherence pattern of EAEC on intestinal cells?
A) Diffuse adherence
B) Localized adherence
C) Aggregative adherence ("stacked brick")
D) No adherence

*Answer: C) Aggregative adherence ("stacked brick")

*Question: Which E. coli pathotype is associated with persistent/chronic pediatric diarrhea?
A) ETEC
B) EPEC
C) EAEC
D) EIEC

*Answer: C) EAEC

*Question: Which E. coli pathotype causes dysentery-like illness similar to Shigella?
A) ETEC
B) EPEC
C) EIEC
D) DAEC

*Answer: C) EIEC

*Question: What does DAEC stand for?
A) Diarrhea-Associated E. coli
B) Diffusely Adherent E. coli
C) Drug-Adapted E. coli
D) Disease-Activated E. coli

*Answer: B) Diffusely Adherent E. coli

*Question: Which E. coli pathotype can cause both diarrhea and UTIs?
A) ETEC
B) EPEC
C) DAEC
D) EHEC

*Answer: C) DAEC

*Question: What is AIEC associated with?
A) Neonatal meningitis
B) Crohn's disease and inflammatory bowel disease
C) Traveler's diarrhea
D) Hemolytic uremic syndrome

*Answer: B) Crohn's disease and inflammatory bowel disease

*Question: What type of toxins does ETEC produce?
A) Shiga toxins
B) Heat-labile (LT) and heat-stable (ST) enterotoxins
C) Hemolysins
D) Cytotoxins

*Answer: B) Heat-labile (LT) and heat-stable (ST) enterotoxins

*Question: What does the locus of enterocyte effacement (LEE) encode in EPEC?
A) Toxin production
B) Attaching and effacing lesions
C) Capsule formation
D) Antibiotic resistance

*Answer: B) Attaching and effacing lesions

*Question: What is Tir in EPEC pathogenesis?
A) A toxin that kills epithelial cells
B) A protein that interacts with intestinal cells to cause actin polymerization
C) An adhesin that binds to receptors
D) An enzyme that degrades mucin

*Answer: B) A protein that interacts with intestinal cells to cause actin polymerization

*Question: What is the alternative name for EHEC?
A) EPEC
B) STEC (Shiga toxin-producing E. coli) or VTEC
C) ETEC
D) EIEC

*Answer: B) STEC (Shiga toxin-producing E. coli) or VTEC

*Question: What does VTEC stand for?
A) Virulent Toxin E. coli
B) Verotoxin-producing E. coli
C) Visceral Tract E. coli
D) Variable Toxin E. coli

*Answer: B) Verotoxin-producing E. coli

*Question: Why is EHEC called verotoxin-producing E. coli?
A) The toxin is green like verdigris
B) The toxin kills monkey kidney (Vero) cells in tissue culture
C) The toxin is produced in large amounts
D) The toxin causes vomiting

*Answer: B) The toxin kills monkey kidney (Vero) cells in tissue culture

*Question: What is the most common EHEC serotype?
A) O26:H11
B) O111:H8
C) O157:H7
D) O145:H28

*Answer: C) O157:H7

*Question: What does the MUG test detect?
A) Mannitol utilization
B) Methylumbelliferyl-β-D-Glucuronide activity
C) Mucoid colonies
D) Motility

*Answer: B) Methylumbelliferyl-β-D-Glucuronide activity

*Question: What is the MUG test result for EHEC?
A) Always positive
B) Rarely produces MUG
C) Always negative
D) Variable

*Answer: B) Rarely produces MUG

*Question: How does EIEC spread from cell to cell?
A) Via flagella
B) Via actin tails to lyse phagolysosome and move between cells
C) Through blood vessels
D) By producing toxins

*Answer: B) Via actin tails to lyse phagolysosome and move between cells

*Question: What are the other two E. coli species mentioned besides E. coli?
A) E. hermanii and E. vulneris
B) E. fergusonii and E. albertii
C) E. blattae and E. marmotae
D) E. coli and E. tarda

*Answer: B) E. fergusonii and E. albertii

*Question: Which E. coli species resembles HUS?
A) E. fergusonii
B) E. albertii
C) Both
D) Neither

*Answer: B) E. albertii

*Question: What type of colonies does Klebsiella produce on MacConkey agar due to capsule?
A) Dry colonies
B) Swarming colonies
C) Mucoid colonies
D) Pigmented colonies

*Answer: C) Mucoid colonies

*Question: Which Klebsiella-associated infection is common in ventilated patients?
A) Urinary tract infection
B) Ventilator-associated pneumonia
C) Wound infection
D) Meningitis

*Answer: B) Ventilator-associated pneumonia

*Question: What are siderophores?
A) Toxins that lyse cells
B) Iron acquisition systems
C) Capsular components
D) Flagellar proteins

*Answer: B) Iron acquisition systems

*Question: Which gene confers plasmid-mediated colistin resistance?
A) bla-KPC
B) mcr-1
C) NDM-1
D) VIM

*Answer: B) mcr-1

*Question: Which Raoultella species converts histidine to histamine?
A) R. planticola
B) R. terrigena
C) R. ornithinolytica
D) All Raoultella species

*Answer: C) R. ornithinolytica

*Question: Which Raoultella species converts melamine to cyanuric acid causing kidney damage?
A) R. planticola
B) R. terrigena
C) R. ornithinolytica
D) R. aquatilis

*Answer: B) R. terrigena

*Question: What is the indole reaction for K. pneumoniae subsp. pneumoniae?
A) Positive
B) Negative
C) Variable
D) Delayed positive

*Answer: B) Negative

*Question: What is the indole reaction for K. pneumoniae subsp. ozaenae?
A) Negative
B) Positive
C) Variable
D) Weakly positive

*Answer: B) Positive

*Question: Which test is positive for K. pneumoniae subsp. ozaenae but not for K. pneumoniae subsp. pneumoniae?
A) Urease
B) Ornithine decarboxylase
C) Citrate
D) VP

*Answer: B) Ornithine decarboxylase

*Question: Which Klebsiella species is the only indole-positive one commonly mentioned?
A) K. pneumoniae
B) K. oxytoca
C) K. aerogenes
D) K. variicola

*Answer: B) K. oxytoca

*Question: What is the IMVIC pattern for Klebsiella species?
A) ++--
B) --++
C) +-+-
D) -+--

*Answer: B) --++

*Question: What biochemical test pattern differentiates Enterobacter from Klebsiella?
A) Lactose fermentation
B) Motility (Enterobacter is motile)
C) VP test
D) Citrate utilization

*Answer: B) Motility (Enterobacter is motile)

*Question: How many species are in the Enterobacter genus?
A) At least 10 species
B) At least 15 species
C) At least 22 species
D) At least 30 species

*Answer: C) At least 22 species

*Question: Which complex includes E. asburiae, E. cloacae, E. ludwigii, and E. hormaechei?
A) E. aerogenes complex
B) E. cloacae complex
C) E. sakazakii complex
D) E. agglomerans complex

*Answer: B) E. cloacae complex

*Question: What property allows Cronobacter to survive in powdered formula?
A) Heat resistance
B) Xerotolerance (survival in dry conditions)
C) Cold tolerance
D) Acid resistance

*Answer: B) Xerotolerance (survival in dry conditions)

*Question: How many Cronobacter species are now recognized?
A) Three
B) Five
C) Seven
D) Ten

*Answer: C) Seven

*Question: What genes require DNA sequencing for accurate Cronobacter identification?
A) 16S rRNA and gyrB
B) fusA and rpoB
C) recA and gyrA
D) ompA and groEL

*Answer: B) fusA and rpoB

*Question: What is the typical pigment color of Cronobacter sakazakii?
A) Red
B) Yellow
C) Green
D) Blue

*Answer: B) Yellow

*Question: Which Citrobacter species is most commonly implicated in infections?
A) C. amalonaticus and C. youngae
B) C. freundii and C. koseri
C) C. farmeri and C. braakii
D) C. sedlakii and C. werkmanii

*Answer: B) C. freundii and C. koseri

*Question: What type of infection is C. koseri specifically linked to in neonates?
A) Urinary tract infections
B) Brain abscesses and neuroinvasive infections
C) Pneumonia
D) Septic arthritis

*Answer: B) Brain abscesses and neuroinvasive infections

*Question: How do Citrobacter species ferment lactose?
A) Rapid lactose fermentation
B) No lactose fermentation
C) Variable/late lactose fermentation
D) Only at low temperatures

*Answer: C) Variable/late lactose fermentation

*Question: Which organism may Citrobacter resemble on laboratory tests?
A) E. coli and Proteus
B) Salmonella and E. coli
C) Shigella and Klebsiella
D) Yersinia and Serratia

*Answer: B) Salmonella and E. coli

*Question: Which is the most prominent Kluyvera species?
A) K. cryocrescens
B) K. ascorbata
C) K. georgiana
D) K. intermedia

*Answer: B) K. ascorbata

*Question: What is the key difference between K. ascorbata and K. cryocrescens?
A) Indole production
B) Glucose fermentation at 5°C (K. cryocrescens positive)
C) Urease activity
D) Motility

*Answer: B) Glucose fermentation at 5°C (K. cryocrescens positive)

*Question: What does "cryo" mean in K. cryocrescens?
A) Capsule
B) Cold (grows at cold temperatures)
C) Crystalline
D) Curved

*Answer: B) Cold (grows at cold temperatures)

*Question: What appearance do Kluyvera colonies have on MacConkey agar?
A) Mucoid appearance
B) Resemble E. coli with bile salt precipitation
C) Green metallic sheen
D) Black colonies

*Answer: B) Resemble E. coli with bile salt precipitation

*Question: What type of flagella does Plesiomonas have?
A) Peritrichous flagella
B) Lateral flagella
C) Polar flagella
D) No flagella

*Answer: C) Polar flagella

*Question: What is the glucose fermentation pattern of Plesiomonas?
A) Ferments with gas production
B) Ferments without gas production
C) Does not ferment glucose
D) Ferments only at low temperatures

*Answer: B) Ferments without gas production

*Question: What is the O/129 susceptibility pattern of Plesiomonas?
A) Resistant
B) Susceptible
C) Variable
D) Intermediate

*Answer: B) Susceptible

*Question: Which organism is O/129 resistant?
A) Vibrio
B) Plesiomonas
C) Aeromonas
D) Yersinia

*Answer: C) Aeromonas

*Question: What agar is used to differentiate Vibrio, Aeromonas, Plesiomonas, and Yersinia?
A) MacConkey agar
B) Blood agar
C) CIN agar
D) Chocolate agar

*Answer: C) CIN agar

*Question: What is the appearance of Plesiomonas on CIN agar?
A) Bull's eye colonies
B) Opaque colonies without a pink center
C) Pink colonies
D) Black colonies

*Answer: B) Opaque colonies without a pink center

*Question: What is Plesiomonas sensitive to that Vibrio is not?
A) Low pH
B) High salt (NaCl)
C) High temperature
D) Oxygen

*Answer: B) High salt (NaCl)

*Question: What is the temperature sensitivity of Plesiomonas?
A) Sensitive to temperatures below 4°C
B) Sensitive to temperatures above 8°C
C) Tolerates all temperatures
D) Only grows at 37°C

*Answer: B) Sensitive to temperatures above 8°C

*Question: What type of diarrhea does Plesiomonas cause?
A) Always bloody diarrhea
B) Watery diarrhea, sometimes dysenteric form
C) No diarrhea
D) Only in neonates

*Answer: B) Watery diarrhea, sometimes dysenteric form

*Question: What patient population has increased Plesiomonas infections?
A) Pregnant women
B) HIV+ patients
C) Diabetic patients
D) Elderly patients

*Answer: B) HIV+ patients

*Question: What antibiotics is Plesiomonas sensitive to?
A) Penicillin and ampicillin
B) Trimethoprim-sulfamethoxazole, aminoglycosides, third-generation cephalosporins, carbapenems
C) Only fluoroquinolones
D) Vancomycin and linezolid

*Answer: B) Trimethoprim-sulfamethoxazole, aminoglycosides, third-generation cephalosporins, carbapenems

*Question: What is the LOA pattern for Pantoea agglomerans?
A) All positive
B) Lysine positive only
C) Triple negative (lysine, ornithine, arginine all negative)
D) Ornithine positive only

*Answer: C) Triple negative (lysine, ornithine, arginine all negative)

*Question: What outbreak was caused by Pantoea agglomerans?
A) Contaminated blood products
B) Contaminated IV fluids causing septicemia
C) Contaminated surgical instruments
D) Contaminated food

*Answer: B) Contaminated IV fluids causing septicemia

*Question: What color pigment do Pantoea species produce?
A) Red
B) Green
C) Yellow
D) Blue

*Answer: C) Yellow

*Question: What is the characteristic colony appearance of Proteus?
A) Mucoid colonies
B) "Burnt chocolate" swarming colonies with concentric rings
C) Pigmented colonies
D) Smooth, shiny colonies

*Answer: B) "Burnt chocolate" swarming colonies with concentric rings

*Question: What type of cells does Proteus produce during swarming?
A) Capsulated cells
B) Elongated, hyperflagellated swarmer cells
C) Spore-forming cells
D) Biofilm cells

*Answer: B) Elongated, hyperflagellated swarmer cells

*Question: What type of kidney stones does P. mirabilis cause?
A) Calcium oxalate stones
B) Uric acid stones
C) Struvite stones (infection stones)
D) Cystine stones

*Answer: C) Struvite stones (infection stones)

*Question: What is the ornithine decarboxylase result for P. mirabilis?
A) Negative
B) Positive
C) Variable
D) Weakly positive

*Answer: B) Positive

*Question: What is the ornithine decarboxylase result for P. vulgaris?
A) Positive
B) Negative
C) Variable
D) Delayed positive

*Answer: B) Negative

*Question: What is the TSI reaction typically seen with P. mirabilis?
A) A/A (yellow/yellow)
B) K/A (red/yellow), often with H2S
C) K/K (red/red)
D) A/K (yellow/red)

*Answer: B) K/A (red/yellow), often with H2S

*Question: Does P. vulgaris ferment sucrose?
A) No
B) Yes, ferments sucrose
C) Only at low temperatures
D) Requires additional carbon source

*Answer: B) Yes, ferments sucrose

*Question: What is the typical TSI pattern for P. vulgaris?
A) K/A
B) A/A (ferments sucrose), with H2S
C) K/K
D) No fermentation

*Answer: B) A/A (ferments sucrose), with H2S

*Question: Which Morganella subspecies ferments trehalose?
A) M. morganii subsp. morganii
B) M. morganii subsp. sibonii
C) Both
D) Neither

*Answer: B) M. morganii subsp. sibonii

*Question: What is the IMU pattern for Morganella morganii?
A) All negative
B) All positive (Indole, Methyl red, Urease)
C) Indole positive only
D) Urease positive only

*Answer: B) All positive (Indole, Methyl red, Urease)

*Question: Is Morganella motile?
A) Non-motile
B) Motile but does not swarm
C) Motile with swarming
D) Only motile at low temperatures

*Answer: B) Motile but does not swarm

*Question: Which Providencia species is specifically mentioned as a UTI pathogen?
A) P. alcalifaciens
B) P. rettgeri
C) P. stuartii
D) P. rustigianii

*Answer: B) P. rettger