Tests Flashcards
BAP Agar
Blood
alpha hemolysis - green and partially hydrolysed
beta hemolysis - clear/yellow and comple hydrolysis
gamma hemolysis - none
MSA Agar
Mannitol salt (10%) inhibits all except staph spp. Mannitol - fermented by staph, color change red to yellow
MacConkey
Selective and Differential: dyes inhibit gram pos, contains lactose so fermented changes to purple
Hektoen Agar
Contains lactose, thiosulfate, ferrous sulfate and green dye
If bact prod H2S, non lactose = green with black center
Salmonella spp.
ENT Agar
Contains bile (inhibs gram pos staph) and sodium azide (inhibs gram pos). Contains esculin and peptone as nutrients and ferric citrate as indicator.
Colonies are dark and spread
Enterococcus faecalis
MYC and SAB
Selective for fungi, acidic and anti-bact
Catalase
Tests if organism can detox some immune chems. (H202 to water)
Coagulase
interacts with prothrombin to clot
Staph aureus
Oxidase test
measures cytochrome oxidase presence. Pos = purple
Pseudomonas aeruginosa
Bile solubility test
if sensitive - clear liquid
strep pneumonia - sensitive
strep mitis - insensitive
Urease test
pink/red = pos; yellow = neg
Proteus spp and H. Pylori
Indole Test
Pos = red (dipstick=blue)
E. Coli
Sensitivity test
Optochin - strep pneu
Novobiocin - staph sapr
Bacitrian - strep pyogenes
PYR Test
Activity of pyrolidonyl arylamidase detected
Pos=pink
Group A strep (pyogenic), Group D Enterococci (Enterococcus spp), coag neg staph spp