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First Aid: Gram-Negatives
Gram-; oxidase+; "comma-shaped;" growth at 42degC
Campylobacter jejuni ("It's hot at summer Camp"). Oxidase+ = Campylobacter, Vibrio cholerae, pseudomonas
Gram-; oxidase+; "comma-shaped;" grows in alkaline media
V cholerae. Oxidase+ = Campylobacter, Vibrio cholerae, pseudomonas
Gram- coccus; ferments maltose (and glucose)
N meningitidis ("MeninGitidis ferments Maltose and Glucose")
Gram- coccus; ferments glucose only
N gonorrhoeae ("Gonorrhoeae ferments only Glucose")
Gram- cocco-bacillus; requires factor V & X for growth on chocolate agar
H influenzae (epiglottitis, meningitis, otitis media, pneumonia in children). Growth w/staph aureus ==> increased b/c S aureus produces NAD+ (factor V) and hematin (factor X) during hemolysis
Gram- cocco-bacillus; infections result from dog/cat bites
Pasteurella ("when the dog bites you, it's time to put it out to pasture")
Gram- cocco-bacillus; cause of whooping cough
Gram- rod; rapid fermenter of lactose
Klebsiella (aspiration pneumonia in diabetics/alcoholics; "red currant jelly sputum") OR E coli (multiple varieties)
Gram- rod; slow fermenter of lactose
Serratia (serratia marascens = maraschino cherries), Citrobacter, etc. (not important)
Gram- rod; lactose non-fermenter; oxidase-; non-motile; H2S- on TSI agar
Shigella (highly virulent). No flagella. Fecal-oral transmission. Invades intestinal mucosa ==> bloody diarrhea. Only 10^1 organisms required for infection.
Gram- rod; lactose non-fermenter; oxidase-; motile; H2S+ on TSI agar
Salmonella spp. Flagellated, can disseminate hematogenously. Invades intestinal mucosa ==> bloody diarrhea.
Gram- rod; lactose non-fermenter; oxidase+
Poorly-staining GNR that visualizes better w/silver stain; grows on charcoal yeast extract w/iron and cysteine