Enterics and NF Flashcards

1
Q

Non-fermenters reservoirs

A

soil, water

human mucous membranes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Non-fermenters cause disease by

A

gaining access to sterile body sites of immunocompromised or debilitated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Suspect a Non-fermenting GNR/GNCB if

A

distinctive colony morphology (not always)
grows NLF on MAC or doesn’t grow at all
oxidase +
AK/NC on KIA or TSI

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

oxidase test

A

determines if isolate prod. enzyme indophenol oxidase
oxidized enzyme prod. color change from yellow===purple
indophenol oxidase oxidizes phenylenediamine oxidase to form indophenol (purple cmpd)
1. add few drops of reagent to strip of filter paper placed on slide
2. streak loopful of organism of reagent saturated paper
3. positive turns purple w/in 30 sec

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

BBL DrySlide oxidase test

A

nnnn-tetramethyl-p- phenylenediamine dihydrochloride (aromatic amine)
if organism prod. cytochrome oxidase it will oxidize cytochrome c which oxidizes reagent to form purple cmpd
1. smear organism onto rxn area of BBL DrySlide Oxidase in area of 3-4 mm
2. examine for drk purple color w/in 20 sec

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Embden-Meyerhof pathway

A

classical metabolic pthwy used by enteric GNR
generates lactic acid and mixed acids
end prod. (strong acids) drops pH and prod. gas
pyruvic acid==other acids (lactic, propionic, formic, acetic, butyric, etc)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Entner-Douderoff pathway

A

most non-fermenters use
end prod. is weak acids
glucose==pyruvic acid==Krebs cycle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Hexose Monophosphate pathway

A

Warburg-Dickins hexose monophosphate pthwy

glucose==pyruvic acid==either goes to krebs cycle or is end prod. of mixed acids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Hugh Leifson OF media

A

detection of weak acid end products (used instead of KIA for NF)
low peptones, high carbohydrates
tube 1 overlay w/ oil, tube 2 no oil
tube 1 green no glucose fermented, tube 2 yellow glucose oxidized=== non fermenter and oxidizer or glucose
tube 1 green, tube 2 green non oxidizer of glucose===non fermenter and non oxidizer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Pseudomonas aeruginosa morph

A
most common non fermenter
prod. pyocyanin (greenish blue sheen)
grape juice/tortilla chip odor
beta hemolytic
feathered, frosted glass apperance
GNR 
fluorescent
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Pseudomonas aeruginosa key tests

A
oxidase +
catalase +
motile
grows @ 42*C
grows on BA and MAC as NLF
LAO =/+/=
OF/O +
OF/F =
some gelatinase +
nitrate +
citrate +
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Pseudomonas aeruginosa pathology

A

exopolysaccharide capsule
noscomial infect (catheter, IV, pneumoniae)
opportunistic (Cystic Fibrosis, burns, cancer)
very resistant- always perform AST (antimicrobial susceptibility testing)
swimmers ear

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Fluorescent pseudomonads

A
oxidase +
prod. pyoverdine but not pyocyanin 
not grow @ 42*C
gelantinase + (fluorescens)/ = (putida)
septicemia in blood bank
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Pseudomonas stutzeri tests

A
yellow wrinkled colonies on BA
NLF on MAC
GNR
oxidase +
motile
grows @ 42*C
LAO =/=/=
oxidizes glucose, lactose (+/=), maltose (+/=), fructose
reduces nitrate to nitrogen gas
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Pseudomonas stutzeri

A

disease in immuno.

otitis media, conjunctivitis, endocarditis, meningitis, wounds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Acintobacter baumannii/calcoaceticus tests

A
2nd most common NF
grows MAC faint pink colony 
lactose +
oxidase =
GNCB
catalast +
oxidizes glucose, xylose, lactose
LAO =/=/=
nitrate =
non-motile
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Acinetobacter lwoffi

A

nonsacchrolytic (not react)
oxidase =
LAO =/=/=
non motile

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Acintobacter baumannii/calcoaceticus reservoir

A

environment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Acinetobacter baumannii/calcoaceticus pathology

A

pneumonia, bronchitis, septicemia, endocarditis, wounds, UTI

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

A. lwoffi pathology

A

septecemia, gastritis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Strenotrophomonas maltophilia morph.

A
3rd most common NF
BAP- lavendar-green colonies
smells like ammonia
MAC pinpoint colonies
GNR
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Stenotrophomonas maltophilia tests

A
oxidase =
ONPG +
oxidizes glucose and maltose
catalase +
DNase +
Geletinase +
hydrolyzes esculin
motile
LAO +/=/=
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Stenotrophomonas maltophilia pathology

A
nosocomial infec.
wound
endocarditis
bacteremia
rare UTI
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Alcaligenes faecalis morph.

A
normal BA (wt @ 48 hrs, green discoloration)/ MAC
green apple odor
GNR tiny
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Alcaligenes faecalis tests
``` nonsaccharolytic oxidase + catalase+ motile reduces nitrite but not nitrate to nitrogen gas LAO =/=/= ```
26
Alcaligenes faecalis pathology
noscomial from water source
27
Achromobacter xylosoxidans morph.
grows on BA and MAC green discoloration of agar GNR
28
Achromobacer xylosoxidans tests
``` oxidase + catalase + motile oxidizes glucose/ xylose nitrate + LAO =/=/= ```
29
Achromobacter xylosoxidans pathology
rarely isolated from blood, CSF, resp., urine, wounds
30
Burkholderia pseudomallei morph.
wrinkled, yellow-brown colonies on BA NLF on MAC (turns pink w/ age due to lactose oxidation) oxidizes xylose, mannitol, maltose GNR may have bipolar staining
31
Burkholderia pseudomallei tests
``` oxidase + motile nitrate + LAO =/+/= grow @ 42*C R to polymixin ```
32
Burkholderia pseudomallei reservoir
water/ soil southeast Asia, N. Australia, Mexico
33
Burkholderia pseudomallei pathology
melioidosis from inhalation/ cut- disseminated abscess formation with skin pustules, septic arthritis, osteomyelitis, spleen, liver, kidneys, and prostate known as Vietnam time bomb considered potential bioterrorist agent
34
Burkholderia cepaia morph.
BA: yellow pigment (or yellow-green) mucoid in cystic fibrosis sweet earthy odor tiny colonies @ 24hr
35
Burkholderia cepacia tests
``` oxidase + (weak and slow) motile glucose and lactose oxidizer LAO +/=/= ONPG + ```
36
Burkholderia cepacia pathology
opportunistic of lungs in cystic fibrosis patients or with chronic granulomatous disease (CGD) [phagocytes not prod. bactericidal anions so get B. cepacia]
37
Elizabethkingia meningosepticum morph.
yellow colony w/ green/lavendar discoloration on BA grows on MAC fruity odor
38
Elizabethkingia meningosepticum tests
``` oxidase + catalase + LAO =/=/= indole + DNase + esculin+ H2S + ONPG + ```
39
Elizabethkingia meningosepticum pathology
newborns: meningitis or septicemia adults: pneumonia, endocarditis, bacteremia, meningitis
40
Chryseomonas and Flovimonas characteristics
``` rarely cause path. oxidase = motile yellow coloines dry wrinkled grow on MAC Chryseomonas- yellow, deep yellow, orange Pseudomonas (Flavimonas) oryzihabitans ```
41
Moraxella spp.
``` rarely cause path. GNCB pinpoint colonies on BA poor to no growth on MAC oxidase + catalase + non motile not oxidize glucose: asaccharolytic (incapable of breaking down carbs for E) Id not performed ```
42
Oligella
``` from urinary tract O. ureolytic: urea +, motile, nitrate + O. urethralis: urea =, non motile, nitrate = but nitrite + no oxidize glucose (asacchrolytic) oxidase + catalast = PDA + ```
43
Shewanella (Pseudomonas) putrefaciens
``` yellow-brown-orange color oxidase+ motile H2S+ on TSI/KIA nitrate + LAO =/=/+ GNR big rods ```
44
Chromobacterium violaceum reservoir
fresh water/ soil in tropics/subtropics SE USA trans. by ingest contam. water/ thru broken skin in immuno.
45
Chromobacerium violaceum charact.
``` grow BA, CHOC, MAC violet pigment (violacein) @ room temp ammonium cyanide odor (almonds) pigment iterfere w/ testing grow anaerobically no pigment oxidase - (v) no grow in high NaCl ```
46
Nitrate test
determine if bacteria reduce nitrate nitrate a (0.8% sulfanilic acid in 5N acetic acid) and nitrate b (0.6% nn-dimethyl-alpha-naphthylamine in 5N acetic acid) reagents 1. innoculate broth incubate 18-24 & 42-48hrs 35-37*C 2. examine for growth and gas 3.if gas nitrate was reduced to nitrogen gas. if growth take 2mL of broth into new tube. Add 5 drops nitrate a and 5 drops nitrate b and mix. If pink/red w/in 2 mins. = + 4. if negative add zinc dust. if pink/red color w/in 2 mins nitrate is present & wasn't reduced so = negative result. If no color change w/in 2 mins. nitrate reduced beyond nitrite and test= positive
47
MAC
selective & differential ID GN bacilli bile salts & crystal violet select for gram negative inhibit gram positive lactose sole carbo. (differential) pH indicator neutral red LF prod acid and turn pH red so prod red/pink colonies peptones, beef extract energy source for NLF
48
Normal enteric flora Enterobacteriacea
``` cause infec. in other areas of body, especially sterile sites Salmonella Shigella Yersinia entercolitica E. coli O157:H7 Plesiomonas ```
49
normal enteric flora (non-Enterobacteriacea)
Campylobacter spp. Aeromonas Vibrios
50
Antigenic serotype Salmonella/Shigella
O: somatic antigen H: flagellar antigen K: capsular antigen Vi: in virulent strains of Salmonella
51
E. coli types
O157:H7 enterotoxigenic E. coli enteropathogenic E. coli enteroaggregative E. coli
52
Escherichia coli morph.
GNR med. grey colony on BA can be beta hemolytic LF on MAC
53
Escherichia coli tests
``` motile indole + ornithine decarboxylase+ MIO +/+/+ O157:H7 sorbitol negative ```
54
decarboxylase test (arginine, lysine, ornithine)
ID GN enteric, NF, oxidase+, GNR, based on prod. of arginine dihydrolase and lysine and ornithine decarboxylase peptones/yeast extract supply nitrogenous nutrients pyridoxal enzyme for aa decarboxylase dextrose is fermentable carbo. bromcresol purple and cresol red pH indicators arginine, lysine, ornithine are added 10g/L to detect enzyme for these- if ferment dextrose lower pH change color, purple to yellow, acidic cond. stimulates decarboxylase- if ferment appropriate enzyme aa degraded yielding an amine (A= citrulline, L= cadaverine, O= putrescine,) elevates pH changing color back to purple, if not stays yellow must add oil
55
Shigella spp.
``` cause severe GI sympotoms Shigella A (dysenteriae) DIRTY Shigella B (flexneri) FINGERS Shigella C (boydii) BRINGS Shigella D (sonnei) SHIGELLA ```
56
Shigella spp. morph.
``` GNR on GS med. grey on BA NLF on MAC non-reactive non-motile sonnei late lactose fermenter ONPG + ```
57
ONPG test
O-nitrophenyl-beta-D- galactopyranoside tests directly for beta galactosidase positive in late lactose fermenters- turns yellow for + bacteria not have permease (LF do have) which allows lactose to enter bact. cell wall where it is broken down into glucose & galactose by beta galactosidase to be metabolized
58
Edwardsiella tarda
``` carride by turtles/reptiles causes diarrhea, wound infec., bacteremia NLF lysine+ H2S + indole + motile urea = citrate = MIO +/+/+ ```
59
Indole test
indole (benzyle pyrrole) metab. degradation prod. of aa tryptophan bact. w/ tryptophanase hydrolyze and deaminiate tryptophan into indole, pyruvic acid, and ammonia. red color cmplx when indole rcts w/ p-dimethylaminobenzaldehyde Kovac's reagent (HCl, p-dimethylaminobenzaldehyde, amyl alcohol) 1.innoculate tube (w/ 18-24hr culture) incubate 35*C for 24-48hrs 2.remvoe 2mL to new tube. add .5mL or 10drops Kovacs reagent. shake. apperance of red ring on surface w/in 30 sec is postive for indole prod.
60
spot indole test
indole combines w/ p-deimethylaminocinnamaldehyde (DMACA) @ acidic pH to prod. blue/ blue-green color 1. saturate filter paper w/ 2 drops indole spot reagent (DMACA) or drop on cotton swab 2. smear w/ 18-24hr culture on BA. observe for blue/blue-green color w/in 1-3 mins
61
Salmonella spp.
``` acute gastroenteritis and typhoid fever (S. typhi) GNR motile H2S + lysine + NLF indole = VP= PDA= urease= API for speciation ```
62
famous Salmonella carrier
typhoid Mary cooked at hospital NY
63
Citrobactereae
``` related to Salmonella C.freundii H2S + looks like Salmonella C.koseri H2S = citrate+ MR+ LF sometimes NLF VP= ONPG+ can mimic Salmonella on Hektoen agar ```
64
Klebsiellae spp.
Klebsiella pneumoniae Klebsiella oxytoca Klebsiella aerogenes
65
Klebsielleae morph
fat shorter GNR muccoid (capsule) LF
66
Klebsiella tests
non motile except K.aerogenes (part of SKY grp) LF VP + (part of KES grp) urea+ K.pneumoniae MIO =/=/=, VP+, bulls eye LF K.oxytoca MIO =/+/=, VP+ K.aerogenes MIO +/=/+, VP + urea =
67
Enterobacter (in Klebsielleae tribe)
``` LF Enterobacter cloacae Enterobacter sakazakii mucoid citrate + MR= VP + motile MIO +/=/+ ```
68
Serratia marcescens (in Klebsielleae tribe)
``` NLF pigmented (pink-orange-red) [false LF+ don't misread] motile VP+ gelatin + arabinose = ```
69
Hafnia alvei (Klebsielleae tribe)
only in immuno. ID w/ automation NLF
70
Proteeae tribe
Proteus Providencia Morganella morganii
71
Proteus spp.
``` swarm Proteus mirabilis: indole =, ornithinine + Proteus vulgaris: indole +, ornithine = can be Salmonella mimic on Hektoen agar H2S+ PDA+ ```
72
Providencia spp.
Providencia retferii Providencia stuartii PDA +
73
Morganella morganii tests
MIO +/+/+ | PDA +
74
Yersinia enterocolitica
``` non motile 37*C motile 25*C ornithine + ONPG + urea + causes GI tract infection rxns similar to S.sonnei ```
75
Yersinia pestis
``` very non reactive MIO =/=/= urea = ONPG + causes plague from rodents/prairie dogs ```
76
CIN agar
differential & selective isolate Yersinia entercolitica GN & GP inhibited by crystal violet, Na deoxycholate and antimicrobials: Cefsuldoin, Irgasan, and Novobiocin incubate @ room temp colonies w/ dark red center surrounded by transparent border are possible Y. entercolitica
77
KIA test
1:10 glucose;lactose H2S ferrous sulfate and Na thiosulfate peptones AK/AK (RED/RED): no fermentation AK/A (RED/YELLOW): only glucose fermented A/A (YELLOW/YELLOW): both glucose & lactose fermented BLACK DEEP: H2S prod. (requires acid environment) black deep w/ red (Salmonella) black deep w/ yellow (Citrobacter)
78
Methyl Red/ Voges Proskauer
positive for one or the other MR: prod. strong acids thru acid fermentation; pH - red color VP: detects acetoin, end prod. of butylene glycol pthwy; add 40% KOH, alpha naphthol - red color
79
Citrate test
detects ability to use citrate as a sole source of energy bromothymol blue in presence of alkaline metabolic prod. green===blue +
80
Urease test
use Christensen's agar Urea, dextrose, phenol red urea breakdown==ammonia===pink+ for fungus too
81
Phenylalanine Deaminase (PDA)
prod. phenyl-pyruvic acid and ammonia | add FeCl3 === green color +
82
Lysine iron agar tube (LIA)
deter. if can decarboxylate lysine and form H2S charac. of Salmonella Ferric ammonium citrate and Na thiosulfate for H2S prod. bromocresol purple pH indicator glucose (dextrose); no lactose lysine to detect decarboxylating lysine LYSINE DECARBOXYLATION DETECT. IN BUTT: purple slant/ purple butt: positive [or black butt] purple slant/ yellow butt: negative fermentation of glucose only LYSINE DEAMINATION DETCT. ON SLANT: positive: red slant negative: slant purple H2S PROD.: postivie: black ppt negative: no black color gas: bubbles/cracks in medium
83
Hugh Leifson OF medium
peptone decreased to reduce formation of alkaline amines that neutralize small amounts of weak acids formed carbo increased to increase amount of acid that forms agar [ ] decreased making it semi solid to permit acid that form on surface to penetrate thru media making pH change easier to see bromothymol blue pH indicator (yellow-acid blue-alkaline) open tube to see if oxidizer
84
Triple Sugar Agar
``` 1% lactose 1% sucrose 0.1% glucose Peptones Ferrous sulfate Screens for Salmonella and Shigella Sucorse for other enterics not Sal & Shig Ak/A Shigella Ak/A H2S Salmonella ```
85
MIO
Low level agar Pancreatic digest of casein, gelatin, yeast extract, bromocresol purple Glucose ferm but no aa decarboxylated yellow Aa decarboxylated purple Ferment glucose==yellow==aa decarboxylated==purple Overlay w/oil Add indole reagent if positive red ring around top