Enterics and NF Flashcards
Non-fermenters reservoirs
soil, water
human mucous membranes
Non-fermenters cause disease by
gaining access to sterile body sites of immunocompromised or debilitated
Suspect a Non-fermenting GNR/GNCB if
distinctive colony morphology (not always)
grows NLF on MAC or doesn’t grow at all
oxidase +
AK/NC on KIA or TSI
oxidase test
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
BBL DrySlide oxidase test
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
Embden-Meyerhof pathway
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)
Entner-Douderoff pathway
most non-fermenters use
end prod. is weak acids
glucose==pyruvic acid==Krebs cycle
Hexose Monophosphate pathway
Warburg-Dickins hexose monophosphate pthwy
glucose==pyruvic acid==either goes to krebs cycle or is end prod. of mixed acids
Hugh Leifson OF media
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
Pseudomonas aeruginosa morph
most common non fermenter prod. pyocyanin (greenish blue sheen) grape juice/tortilla chip odor beta hemolytic feathered, frosted glass apperance GNR fluorescent
Pseudomonas aeruginosa key tests
oxidase + catalase + motile grows @ 42*C grows on BA and MAC as NLF LAO =/+/= OF/O + OF/F = some gelatinase + nitrate + citrate +
Pseudomonas aeruginosa pathology
exopolysaccharide capsule
noscomial infect (catheter, IV, pneumoniae)
opportunistic (Cystic Fibrosis, burns, cancer)
very resistant- always perform AST (antimicrobial susceptibility testing)
swimmers ear
Fluorescent pseudomonads
oxidase + prod. pyoverdine but not pyocyanin not grow @ 42*C gelantinase + (fluorescens)/ = (putida) septicemia in blood bank
Pseudomonas stutzeri tests
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
Pseudomonas stutzeri
disease in immuno.
otitis media, conjunctivitis, endocarditis, meningitis, wounds
Acintobacter baumannii/calcoaceticus tests
2nd most common NF grows MAC faint pink colony lactose + oxidase = GNCB catalast + oxidizes glucose, xylose, lactose LAO =/=/= nitrate = non-motile
Acinetobacter lwoffi
nonsacchrolytic (not react)
oxidase =
LAO =/=/=
non motile
Acintobacter baumannii/calcoaceticus reservoir
environment
Acinetobacter baumannii/calcoaceticus pathology
pneumonia, bronchitis, septicemia, endocarditis, wounds, UTI
A. lwoffi pathology
septecemia, gastritis
Strenotrophomonas maltophilia morph.
3rd most common NF BAP- lavendar-green colonies smells like ammonia MAC pinpoint colonies GNR
Stenotrophomonas maltophilia tests
oxidase = ONPG + oxidizes glucose and maltose catalase + DNase + Geletinase + hydrolyzes esculin motile LAO +/=/=
Stenotrophomonas maltophilia pathology
nosocomial infec. wound endocarditis bacteremia rare UTI
Alcaligenes faecalis morph.
normal BA (wt @ 48 hrs, green discoloration)/ MAC green apple odor GNR tiny