MICROBIOLOGY BLOCK V

BA- blood agarCA- chocolate agarCAMP- Christie, Atkins, Munch-PetersenEMB- eosin methylene blue agarBIOCHEM- biockemical tests such as TSI, indole, methyl red, voges-proskauer, citrate, urease, SIM, etc.CHO- sugar fermentation testsSIM- sulfite indole motilityLJ- lowenstein-jensen mediumUBT- urea breath testMAC- mac conkey agarTCBS- thiosulfate citrate bile salt sucrose agarTSI- triple sugar ironBGA- brilliant green agarSSA- salmonella- shigella agarHEA- hektoen- enteric agar

1. Streptococcus pneumoniae (BA, CA) gram- positive diplococci which is lancet or bullet-shaped - hemolytic optochin test positive: > 14 mm inhibition means that optochin (ethylhydrocupreine hydrochloride)

selectively inhibited the growth of the organism bile solubility test positive: sodium deoxycholate and sodium taurocholate are able to lyse S.

pneumoniae neufeld reaction: a.k.a. Quellung or capsular swelling seen when equal amounts of the body fluid

with the organism is mixed with S. pneumoniae- specific capsular antisera and this makes the capsule swell

2. Streptococcus agalactiae (BA, CA, CAMP) gram- positive streptococci - hemolytic BA: pinpoint, clear colonies CAMP: with arrowhead hemolysis when grown with Staphylococcus aureus

3. Klebsiella pneumoniae (EMB, BIOCHEM, CHO) gram- negative coccobacilli usually occurring in pairs capsulated and non-motile a.k.a. Friedlander’s bacillus EMB: large, purple, mucoid colonies BIOCHEM:

TSI H2S I M Vi C UREASE SIMSLAN

TBUT

TA AG - - - + + + -

CHO:

GLUCOSE

LACTOSE

MALTOSE

MANNITE

SUCROSE

RHAMNOSE

SALICIN XYLOSE INOSITE DULCITE

AG AG AG AG AG A AG A AG V

4. Haemophilus influenzae (BA, CA) gram- negative, non-motile coccobacilli has the type B capsule a.k.a. Peiffer’s bacillus requires X and V factors for growth

o X factor: protoporphyrin IX which is a precursor of hemin; heat stableo V factor: NAD or nicotinamide adenine dinucleotide; heat labile

needs 10% CO2 that is why the agar plate is placed in a candle jar BA may not support its growth if RBC is intact

5. Listeria monocytogenes (BA, SIM) aerobic, non-sporeforming gram-positive bacilli BA: small, smooth, translucent, gray with a narrow zone of - hemolysis SIM: umbrella-shaped pattern after overnight incubation at room temperature cold enrichment can increase the recovery: place the specimen at 4C before subculturing

6. Mycobacterium tuberculosis (LJ, SIM) slender, slow-growing, aerobic gram-positive diplobacilli acid- fast bacilli LJ medium: non-pigmented, rough, buff colonies

7. Helicobacter pylori (UBT) microaerophilic gram-negative spiral urea breath test positive

8. Escherichia coli (EMB, MAC, BIOCHEM, CHO) gram- negative coccobacilli with variable motility either capsulated or motile EMB: deep purple colonies with greenish metallic sheen

MAC: pink colonies BIOCHEM:

TSI H2S I M Vi C UREASE SIMSLAN

TBUT

TA AG - + + - - - -/+

CHO:GLUCOSE

LACTOSE

MALTOSE

MANNITE

SUCROSE

RHAMNOSE

SALICIN XYLOSE INOSITE DULCITE

AG AG AG AG V AG V AG - V

9. Vibrio cholerae (TCBS, TSI) gram- negative bacilli, comma- shaped and motile by means of a thick polar flagellum

(monotrichous) oxidase positive culture media of choice: TCBS TCBS: flat yellow colored colonies with an opaque center and transparent periphery

10. Salmonella paratyphi A (BGA, BIOCHEM, CHO) gram- negative motile bacilli culture medium of choice: BGA BGA: pink-white colonies on an intense red background

BIOCHEM:TSI H2S I M Vi C UREASE SIM

SLANT

BUTT

Alk AG - - + - - - +

CHO:GLUCOSE

LACTOSE

MALTOSE

MANNITE

SUCROSE

RHAMNOSE

SALICIN XYLOSE INOSITE DULCITE

AG - AG AG - V - - - V

11. Shigella flexneri (SSA, HEA, BIOCHEM, CHO) gram- negative, non-motile bacilli best specimen for culture is a rectal swab of an ulcer taken by sigmoidoscopy culture medium of choice: SSA SSA: colorless colonies

HEA: blue-green to green colonies

BIOCHEM:TSI H2S I M Vi C UREASE SIM

SLANT

BUTT

Alk A - -/+ + - - - -

CHO:GLUCOSE

LACTOSE

MALTOSE

MANNITE

SUCROSE

RHAMNOSE

SALICIN XYLOSE INOSITE DULCITE

A - V A V - - - - -