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2.2 microbiology > Denise - Enterobacterales > Flashcards

Denise - Enterobacterales Flashcards

1
Q

Write about the enterobacterales species

A

Gram negative bacilli
Facultatively anaerobic
Ferment glucose
Reduce nitrate to nitirite
Oxidase negative
Weak catalase positive
Most motile
Some capsulated

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2
Q

List the eight enterobacterales

A

Lactose fermenters:
Escherichia
Citrobacter
Enterobacter
Klebsiella

Non lactose fermenters
Shigella
Proteus
Salmonella
Yersenia

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3
Q

Write about the four factors of enterobacter pathogenesis

A

Enteropathogens in the GIT

Uropathogens in the UTI

Opportunistice infections

HCAIs

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4
Q

Give some examples of opportunistic infections caused by enterobactet

A

Central nervous system infection (Escherichia)

Lower respiratory tract infection

Blood stream infection

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5
Q

What enterobacters can cause a lower respiratory tract infection

A

Klebsiella
Enterobacter
Escherichia

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6
Q

What enterobacters can cause bloodstream infections

A

Escherichia
Klebsiella
Enterobacter

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7
Q

What enterobacters can infect the GIT

A

Salmonella
Shigella
Escherichia
Yersinia

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8
Q

What HCAIs are caused by enterobacter

A

Blood stream infections
Catheter associated UTIs
Ventilator associated pneumonia
Antimicrobial resistance

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9
Q

What infections does Escherichia, Salmonella and Yersinia cause

A

infection within the GT and outside the GIT

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10
Q

What infections does Shigella cause

A

Primarily gastrointestinal

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11
Q

What infections does Klebsiella, Enteobacter and Citrobacter cause

A

Primarily extraintesitinal

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12
Q

what are sources of enterobacterales
(3)

A

Faeces from humans/animals containing pathogens/toxins

This is then ingested through food or liquid (milk or water) or on your fingers

Ingestion of organism and/or toxins

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13
Q

what happens upon ingestion of organisms and/or toxins

A

Organisms multiply and toxins produced but infection remains localised -> diarrhoea -> pathogen in faeces

Organisms invade or toxins are absorbed -> dissemination -> symptoms of systemic infection fever

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14
Q

How are faecal specimens processed in the lab

A

Evaluate specimens macroscopically based on appearance

Direct molecular detection is carried out - if positive then further testing is carried out

Enrichment broths and sub culturing onto selective plates

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15
Q

What investigation must be done for cryptosporidium/giardia faecal specimens

A

Smear microscopy

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16
Q

What treatment shous clostridium diff/perfringens and B. cereus feaces undergo?

A

Pretreatment
Alcohol shock
Toxin detection

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17
Q

Explain the conventional micro process of laboratory investigation of faeces

A

Faeces -> broth for 24 hours -> selective agar for 24 hours -> biochemical ID -> serotyping

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18
Q

Explain the contemporary micro process of laboratory investigation of faeces

A

Direct detection via Real Time PCR or EntericBio

Same day detection of target gene

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19
Q

Write about E. Coli

A

Common constituent of mammalian digestive tracts
Predominant facultative anaerobe
Essential for our well being:
- improves digesiton
- produces essential vitamins
- competitive exclusion

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20
Q

Write about the diversity of E. Coli: Seroty[es

A

Tradition classification made on the basis of presence of three antigens O, K and H antigens

A combination of O and H antigens have been identified and used to serotype E. Coli

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21
Q

Give some examples of E. Coli serotypes

A

O157:H7
O104:H4
O26
O103
O111

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22
Q

How does E. Coli acquire virulence genes

A

Horizontal gene transfer

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23
Q

What are the three steps of horizontal gene transfer

A

Transfer of virulence genes via plasmids
- Conjugation
- Transduction
- Transformation

Or transfer of virulence genes via bacteriophages

Change of vell to virulence

Virulence genes bringing about:
- adherence
- enterotoxins
- invasiveness
- cytotoxicity

Due to intestinal disease

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24
Q

Describe intestinal pathogenic E. Coli, what are the different strains causing intestinal infection
(6)

A

Enterotocigenic (ETEC)
Enteropathogenic (EPEC)
Enteroaggregative (EAEC)
Enteroinvasive (EIEC)/Shigella
Diffuse adhering (DAEC)
Shiga toxin producin (STEC) and other enterohemorrhagic (EHEC)

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25
Q

What strain of E. Coli causes extraintestinal infection

A

ExPEC
- uropathogenic
- strains associated with neonatal meningitis

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26
Q

What infections does enterotoxigenic (ETEC) cause

A

Watery diarrheae

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27
Q

What infections does enteropathogenic (EPEC) cause

A

Watery diarrhear of lung duration
Mostly in infants, often in developing countries

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28
Q

What infections does Enterohaemorrhagic E. Coli cause

A

EHEC

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29
Q

What infections does Enterohaemorrhagic E. Coli (EHEC) cause

A

Bloody diarrhea
Haemorrhagic colitis and haemolytic uremic syndrome (HUS)

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30
Q

What does infection enteronvasive (EIEC) cause

A

Blood diarrhea

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31
Q

What infection does enteroadherant E. Coli (EAEC) cause

A

Persistent watery diarrhea in children and patients infected with HIV

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32
Q

Write about enteropathogenic E. Coli

A

Induces the formation of pedestals on the host cell surface

Causes infantile diarrhoea mostly in the tropics

Caused by poor hygiene

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33
Q

Explain the pathogenesis of Enteropathogenic E. Coli

A

Induces the formation of pedestals on the host cell surface

Causes infantile diarrhoea mostly in the tropics

Caused by poor hygiene

Non invasive

Does not produce toxins

Adherence to intestinal mucosa

Small intestine effacement

Plasma encoded protein

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34
Q

What does enteropathogenic E. Coli secrete

A

Intimin and TIR

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35
Q

What does secretion of intimin and TIR by EPEC do

A

Destroys microvilli

Loss of absorbtive surface

Leads to diarrhoeae

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36
Q

Write about EnteroInvasive E. Coli (EIEC)

A

Inflammatory dysentry
Bloody diarrhoea
Large intestine
Intracellular pathogen
fever

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37
Q

Explain the pathogenesis of EIECs

A

Invades the basolateral surface
- invasion plasmid antigen
- Ipa gene
Lateral spread
Food, water and person-to- person transmission

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38
Q

Write about enterotoxigenic E. Coli

A

Non inflammatory
Diarrhoae in children in developing countries
Travellers Diarrhoea

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39
Q

Write about the pathogenicity of ETEC

A

Colonisation factor antigen
LT heat-labile toxin activates adenylate cyclase-increases production of cAMP
ST heat-stable toxin activates guanylate cyclase- increased production of cGMP
Increased fluid secretion = diarrhoae

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40
Q

Write about EHEC

A

E. Coli 0157
Shiga toxin production
Hemolysin
LEE

Mobile genetic elemets:
- phages
- genomic islands
- plasmid

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41
Q

What infections does E. Coli 0157:H7 cause

A

Intestinal
- asymptomatic
- watery diarrhoea
- haemorrhagic colitis

Systemic
- haemlytic uremic syndrom HUS

Causes:
- Thrombotic thrombocytopenic purpura (TTP)
- kidney failure
- haemolytic anaemia

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42
Q

What does infection of 0157:H7 cause

A
  • Thrombotic thrombocytopenic purpura (TTP)
  • kidney failure
  • haemolytic anaemia
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43
Q

What is E. Coli 0157 called

A

EHEC
STEC
VTEC

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44
Q

Write about the epedemiology of STEC/VTEC infections

A

Ireland had the highest annual incidence of VTEC between 2009 and 2018 with the exception of 2011

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45
Q

Write about the day 1 investigation of E. Coli

A

Clinical sample = faeces

Direct detection of shiga toxin genes by entericBio real time PCR

Selective culture on day 1 is positive

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46
Q

What selective media should E. Coli be put up on

A

MacConkey for all E. Coli

STEC
- STEC chromagar
- CTSMAC (Cefixime Tellurite sorbitol MacConkey)

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47
Q

Explain the use of Enteric Bio real time PCR for detection of VTEC/EHEC

A

Real-time detection of pathogens directly from faeces

Without pre-enrichment DNA

DNA extraction amplification and detection

Rapid result 3 hours Day 1

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48
Q

Write about Enteric Bio Panels for Bacteria, what can we test for

A

Shiga toxin (1)
Shiga toxin 2
Salmonella/Shigella/Campylobacter
Yersinia
Vibrio
Clostridium difficile

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49
Q

What parasites can we detect with enteric bio

A

Cryptosporidium/Giardia
Entamoeba

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50
Q

What viruses can be detected with Enteric Bio

A

Norovirus, Rotavirus, Adenovirus

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51
Q

Where is the reference lab for VTEC/EHEC

A

Cherry Orchard

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52
Q

Write about VTEC isolation on CT SMAC agar

A

Sorbitol fermenters = pink e.g. non 0157H7

Non sorbitol fermenter = colourless e.g. O157H7

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53
Q

Write about STEC Chromagar

A

Detects most common Shiga-toxin E. Coli serotypes -> mauve colonies

Other enterobacterales are coulerless, blue or inhibited

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54
Q

Write about the day 2 investigation of E. Coli

A

GNBs
Oxidase negative
Weak catalase positive

Biochemical screen: IMVic Test

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55
Q

What is meant by the IMVic test

A

I: indole
M: methyl red
V: Voges-Proskauer
iC: citrate

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56
Q

What are the biochemical IMVic results for E. Coli

A

I: produces indole
M: methyl red positive
V: negative
iC: negative

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57
Q

Write about the indole test

A

 decompose the amino acid tryptophan to indole
 accumulates in the medium
 Inoculate a peptone water
 Incubate 24 hrs @ 37
 When indole is combined with Kovac’s Reagent
 yellow to cherry red
 an oily layer at the top of the broth.

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58
Q

Write about the methyl red test

A

 Methyl Red Test
 detection of end products from the
metabolism of glucose.
 Inoculate a buffered glucose
 the fermentation of glucose.
 MR Positive: When the culture medium turns red
after addition of methyl red
 pH at or below 4.4

59
Q

Write about Voges-Proskauer test

A

 Voges-Proskauer Test
 detection of end products from
the metabolism of glucose.
 produce acetoin as the chief end
product of glucose metabolism
 Heavy inoculum
 Add 40% KoH and alpha Napthol
 Shake vigorously
 Colour development within 15 mins
 Voges-Proskauer negative

60
Q

Write about Simmons Citrate

A

 Simmons Citrate Test
 use citrate as sole carbon source

Growth usually results in the bromothymol blue
indicator, turning from green to blue.

The alkaline carbonates and bicarbonates produced as by-products of citrate catabolism raise the pH of the medium to above 7.6

61
Q

Write about all of the biochemical test results for E. Coli

A

 produces indole
 methyl red positive
 Voges-Proskauer negative
 cannot use citrate as sole carbon source
 Lactose Fermenter
 produces lysine decarboxylase
 ferments sorbitol except E. coli O157 H7
 produce β-glucuronidase except E. coli O157 H7

62
Q

What two methods of automated identification can be used for E. Coli

A

Vitek
MaldiTOF

63
Q

Write about use of Vitek for E. Coli

A

ID and sensitivity
ID 64 individual substrate tests
Colourmetric

64
Q

Write about use of MaldiTOF for E. COli

A

Cannot differentiate between E. Coli and Shigella
93% of their genes are common

65
Q

What are the four species of shigella studied

A

Shigella dysenteriae - serogroup A
Shigella flexneri - serogroup B
Shigella boydii - serogroup C
Shigella sonnei - serogroup D

66
Q

Which is the most serious shigella species

A

Shigella flexneri
Shigella boydii

Shigella sonnei is the most severe

67
Q

Write about shigella species

A

Reservoir is humans

Food = chicken, tuna and potato salad

Spread via faecal-oral route through food, faeces, fingers, flies and fomites

Fragile in human faeces

Incubation time of 24-50 hours

68
Q

What are the symptoms of shigella

A

Diarrhoeae
Abdominal pain
Fever

Might become invasive

69
Q

Write about shigella infection

A

Toxin mediated infection
Shiga toxin (AB toxin)
Bloody diarrhoea
Infective does < 200 cells

70
Q

Write about shigella epidemiology

A

8 shigellosis outbreaks in 2018
Large outbreak of shigellosis in 2017 in HSE

71
Q

Write about the day 1 laboratory investigation of shigella

A

Faeces sample

Direct Detection

Selective culture

72
Q

How is direct detection of shigella carried out

A

Real Time PCR
EntericBio
BD Max
Syndromic Testing
BioFire GI panel

Shigella Ipa gene DNA detected on Day 1

73
Q

What selective culture is used for shigella

A

XLD
DCA

74
Q

What is the day 2,3 investigation of shigella

A

Day 2 = reading XLD and DCA agar

Day 3 = biochemical ID, serotyping

75
Q

Write about deoxycholate citrate agar

A

Selective factors include sodium deoxycholate and sodium citrate

Differential factors are lactose and sodium ferric chloride

Lactose fermenters = commensals = pink
Shigella = NLF = pale
Salmonella = NLF = pale with H2S positive black centre

76
Q

Write about XLD media

A

Selective factor is sodium deoxycholate
Differential factors are Xylose, lysine, H2S

Lactose fermenters = commensals = yellow
Shigella = xylose lysine = red
Salmonella = red with black centre

77
Q

Write about shigella on chrom GTI

A

Teal coloured colonies
Non-H2S producing salmonellas will look the same

78
Q

What are the basic characteristics of Shigella

A

GNBs
Oxidase negative
Weak catalase positive

Non motile
Late lactose fermenter

79
Q

Write about biochemical results for shigella

A

Indole negative
Methyl red positive
Vogues negative
Citrate negative
urease negative
Lysine decarboxylase negative

80
Q

Where is the shigella reference lab

A

University Hospital Galway

Salmonella and Shigella Listeria Reference Lab

81
Q

What are the main reservoirs for salmonella

A

Foodborne - eggs
Zoonotic - lizards
Human - typhoid mary

82
Q

What are the main species of salmonella studies

A

S. Typhimurium
S. Enteritidis
S. Typhi
S. Paratyphi
S. cholerae suis

83
Q

What infection does S. cholerae suis cause

A

Septicaemia

84
Q

What infection does S. enteriditis and S. typhimurium cause

A

Gastroenteritis

85
Q

What infection does S, paratyphi and S, typhi cause

A

Parathyphoid fever or thyphoid fever

Leads to enteric fever

86
Q

What are the virulence factors of Salmonella

A

Peptidoglycan
Fimbrae/Pilli
Salmonella Pathogenicity islands
Type 3 secretion system
Flagellin

Vi antigen of S, typhi

87
Q

What is special about S. typhi

A

Vi antigen

88
Q

How does S. enteritidis and S, typhimurium cause gastroenteritis

A

Invasion of M cell of intestine
Passes into tissue
Uptake by Neutrophils, dendritic cells and macrophages
Limited dissemination i.e. they can’t spread out of intestine

89
Q

How does S. typhi and S. paratyphi cause typhoid fever

A

Invasion through M cells
Macrophage uptake
Intramacrophage replication
System dissemination i.e. spread to other organs such as the gallbladder

90
Q

How does S. typhi cause enteric fever

A

Uptake through small intestine

Spread to other organs such as gallbladder and lymph nodes

Gallbladder infection leads to cholecystitis and a carrier states

Infection of small intestine caused inflammation and ulceration of intestinal which causes diarrheae and hemorrhage or performation

91
Q

Explain what happens when S. typhi infects the lymphatic system
(5)

A

S, typhi passes from small intestine into lymph

Travels to lymph nodes

Enters circulation via thoracic duct (bacteremia) + fever + malasie

Infection of liver, spleen ,kidney, bone marrow etc (secondary bacteremia)

Causes fever, slow pulse, enlarged liver and spleen ,rose spots and low WBC count

92
Q

Write about Salmonella epidemiology

A

11 cases of S, Typhi many associated with travel
5 cases of S, paratyphi associated with India

93
Q

Write about day 1 investigation of salmonella

A

Direct detection of Salmonella Inv gene

Selective enrichment on selenite broth

94
Q

How is direct detection of salmonella carried out

A

Real Time PCR
EntericBio
Syndromic testing
BioFire GI panel

Inv gene DNA detected

95
Q

What selective agar is used for Salmonella

A

Selenite broth

96
Q

What is the day 3 investigation for salmonella

A

XLS
DCA
Chromagar

97
Q

What is the day 4 investigation of salmonella

A

Biochemical ID
Serotyping

98
Q

Write about samples for Salmonella

A

Cat 3 facilities required

Enteric fever:
- blood culture
- faeces
- urine
- bone marrow aspirate

Gastroenteritis
- faeces

99
Q

Write about selenite broth for Salmonella

A

Selenite broth
Enhances culture yield by reducing growth of faecal coliforms and faecal streptococci.
Take sub-cultures of broth from the upper third of the broth column should be at least 5 cm in depth.
Better for enrichment of Salmonella Typhi
37 not exceeding 18 hours

100
Q

Write about XLD agar for Salmonella

A

 Lactose Fermenters Commensals yellow
 Shigella xylose Lysiene red
 Salmonella red with black centres

101
Q

Write about DCA agar for Salmonella

A

 Lactose Fermenters Commensals pink
 Non-lactose fermenters are colourless pale
 Shigella NLF pale
 Salmonella NLF pale
 Many Salmonella spp H2 S pos

102
Q

Write about Bismith Sulphite agar for Samonella

A

 S Typhi and Paratyphi
 BS and Brilliant Green
Selective

103
Q

Write about Salmonella on Chromagar

A

Teal coloured colonies with black centres

104
Q

What are the basic characterisations for Salmonella

A

Motile
Non Lactose Fermenter
Oxidase Negative
Weak Catalase Positive
GNB

105
Q

Write about the biochemical results for Salmonella

A

 I : negative
 M: positive
 V: negative
 iC: positive
 urease negative
 lysine decarboxylase positive

106
Q

What are the components of the lysine decarboxylase test

A

Glucose
Lysine
Bromocresol Purple

107
Q

Write about the Kauffman-White Classification of Salmonella

A

 Differentiates isolates based on surface antigens
 First “O” antigen type is determined- associated with LPS of outer membrane
 Then the “H” antigen is determined- associated with flagella
 Salmonella exist in two phases; a motile (specific) phase and a non-motile (nonspecific phase
 Different “H” antigens are produced depending on the phase in which the salmonella is found

108
Q

What are the three main Salmonella antigens

A

O-somatic cell wall antigens
H-flagellar antigens
Vi-antigens (enteric fever strains)

109
Q

What do we do with a confirmed salmonella case

A

Whole genome sequencing
Antimicrobial resistance

110
Q

Write about whole genome sequencing for salmonella

A

Done for:
- serology
- antimicrobial susceptibility
- epidemiological typing
- outbreak investigation

111
Q

Write about the antimicrobial resistance in Salmonella

A

 21% MDR
 3 or more antimicrobials
 1/3 profile of resistance
to ampicillin, sulphonamide and tetracycline (ASuT) were mainly monophasic S. Typhimurium
 1 ESBL
 S.Brandenburg

112
Q

What are the three most important yersinia species

A

Yersinia pestis
Yersinia enterocolitica (foodborne)
Yersinia pseudotuberculosis

113
Q

Write about yersinia pestis infection

A

Plague - caused by yersinia pestis

Bubonic plague

114
Q

Write about bubonic plague

A

Swollen and painfil axillary (arm pit) and inguinal (groin) lymph nodes (buboes)

Transmitted from mammalian reservoirs by flea bites or contact with contaminated animal tissues

If infection spread to lung from lymph it caused pneumonic plague
Person-to person spread

115
Q

Write about yersinia enterocolitica infection

A

Enterocolitis
Causes enterocolitis with diarrhoeae fever abdominal pain
Invasion of the ileum
Necrosis of the Peyers Patches
Inflammation of the mesenteric lymph nodes
1/4 of children develop blood diarrhoea
Appendicitis type syndrome in children
BSI in elderly

6 cases in 2018

116
Q

Write about yersinia spread

A

Reservoir: animals, rats, pets, soil, lakes
Food: milk, PORK, poultyr, shellfish, vegetables
Psychotrophic growth at 4 degrees
Cold chain food products hazards
Enteric zoonosis
Incubation time 24-36 hours

117
Q

What are symptoms of Enteric zoonosis

A

Diarrhoea
Vomiting
Fever
Headache
Pseudoappendicitis

118
Q

Write about day 1 yersinia investigation

A

Direct detection via:
- rela time PCR
- BD max
- Syndromic testing
- BioFire GI panel

Yersenia gene DNA detected

Selective culture on CIN agar

119
Q

What are the basic characteristics of yersinia

A

GNBs
Oxidase negative
Weak catalase positive
Motile at 25 not 37
Non lactose fermenter

120
Q

What is CIN agar

A

Selective for yersinia

Cefsulodin, irgasan, novobiocin agar

121
Q

What are the biochemical results for Yersinia

A

Indole positive
Methyl red negative
Vogues positive
Citrate negative
Urease positive
Lysine negative
Ornithine decarboxylase positive

122
Q

What three things caus urinary tract infections

A

UroPathogens
Escherichia
Proteus

123
Q

Give an example of a urpathogen

A

E. Coli UPEC

124
Q

Write about EPEC

A

80% of UTIs
Endogenous infection

125
Q

How can EPEC cause an infection

A

Contamination of urethral with EPEC from gut
Colonisation of urethra with migration towards bladder
Colonisation and invasion of bladder mediated by pili and adhesion
Inflammatory response in bladder and fibrinogen accumulation in the catheter
Neutrophil infiltration
Bacterial multiplication and immune system subverison
Biofilm formation
Epithelial damage by bacterial toxins and proteases
Ascension to the kidneys
Colonisation of the kidneys
Host tissue damage by bacterial toxins
Bacteraemia

126
Q

Write about Chromagar

A

E. coli - dark pink to red
Enterococcus - turquoise blue
Klebsiella, Enterobacter, Citrobacter - metallic blue
Proteus - brown hali

Pseudomonas - cream/translucent
S. aureus -> golden/opaque
S. saprophyticus -> pink small

127
Q

Write about UPEC biochemical tests

A

Indole positive
Methyl red positive
Vogees negative
Citrate negative
urease negative
Lysine dacarb positive
Dulcitol positive
Lactose positive

128
Q

Write about proteus

A

Second most common cause of UTI
Proteus mirabilis
Sample = mid stream urine

129
Q

Write about isolation of proteus

A

Not fastidious
Highly motile-form ‘swarm’
No swarm on macConkey (NLF)
Chromogenic UTI medium brown

130
Q

Write about the biochemical results for proteus mirabilis

A

Indole negative
MR positive
VP negative
Citrate positive
Urease positive
Lysine decarboxylase -
Dulcitol -
Lactose -
Phenylalanine postiive

131
Q

Write about extra intestinal E. Coli

A

Neonatal meningitis
- 30% caused by E. Coli not HCAI

Bloodsteam infection
- progression from UTI

132
Q

What are the two main enterobacters involved in HCAI

A

Klebsiella pneumonia
Enterobacter species

133
Q

How do you remember the HCAIs

A

ESKAPE

Enterococcus faecium
S. aureus
K. pneumoniae
Acinetobacter baumannii
P. aeruginosa
Enterobacter species

134
Q

What are the four main HCAIs

A

Central line associated blood stream infections
Catheter associated UTI
Ventilator associated pneumonia
Antimicrobial resistance

135
Q

Write about Klebsiella species

A

Commensal but frequently an opportunistic pathogen causing BSI, HCAI UTI, VAP pneumoniae

Specimens: blood, urine, sputum

Screen for carriage -> rectal swabs and faeces

136
Q

Write about Klebsiella antimicrobial resistance

A

Carbapenemase producing enterobacterales CPE

137
Q

What are the basic characteristics of Klebsiella

A

Not fastidious
Mucoid colonies
Basic characterisation (GNBs Ox negative weak cat positive)

138
Q

Write about the Klebsiella Biochemical tests

A

Indole negative
MR negative
VP positive
Citrate postiive
Urease V positive (K. pneumo)
Lysine decarboxylase +
Dulcitol +

139
Q

Write about enterobacter species

A

 Opportunistic Infections
 Health Care Acquired Infection
 Antimicrobial Treatment
 Catheters
 Invasive Procedures
 Burns/ wounds
 Pneumonia
 UT

140
Q

Write about Enterobacter ID

A

LF on MacConkey
Non fastidious
GNB
Oxidase negative
Weak catalase postiive

API or Vitek can be used

141
Q

What are the biochemical results for enterobacter

A

Indole negative
MR negative
VP positive
Citrate postiive
Urease negative
Lysine decarboxylase negative
Dulcitol negative

142
Q

Write about citrobacter species

A

 Inhabitant of soil and water and found in GIT
 Citrobacter freundii- main pathogen
 Healthcare-associated infection, UTI, bacteraemia

143
Q

What are the biochemical results for citrobacter species

A

I : produces indole -
 M: methyl red positive +
 V: Voges-Proskauer negative -
 iC: cannot use citrate as sole carbon source +
 Urease -
 Lysine Decarboxylase -
 Dulcitol –
 Lactose + LF

144
Q

Look at slide 100 to learn biochemical tests

A

Look at slide 100 to learn biochemical tests

2.2 microbiology (60 decks)

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