Things to Do Today• Observe Unknown gm (-) results• Start Urinalysis• Start gm (+) ID

– Check for hemolysis

– Catalase test

– Coagulase test

– Direct stain colonies

• Observe Throat cultures– Check for hemolysis

– Catalase test

– Gm stain “isolated colonies”

Oxidase Test

Negative Positive

Urease Test

Negative Positive

Methyl Red Test

Negative Positive

KIA Slants

uninoculated

KIA Slants

uninoculated

Citrate test

Negative positive

The Enterotube Multitest System

The API System: Various species of Enteobacteriaceae are shown here with differences in reactions that enable them to be identified

Things to Do Today• Observe Unknown gm (-) results

– Perform oxidase test with culture from KIA slant

– Observe Urease tubes– Perform MR test by adding 6-8 drops MR

reagent to the culture– Observe KIA slants for the various reactions

Three species of Candida can be differentiated in mixed culture when grown on CHROMagar Candida plates

Identification of urinary tract pathogens with

differential media (CHROMagar)

EMB with E. coli

Used with permission

EMB

Pseudomonas auginosa

Enterobacter aerogenes

Fig. 15-22

Relative Frequencies of Nosocomial Infections I

John Wiley

Fig. 15-19

Relative Frequencies of Nosocomial Infections II

John Wiley

Things to Do Today• Start Urinalysis

– Do a 4 quadrant streak with the urine sample using a metal loop onto the EMB plate

– Perform the “$” streak with the urine sample using the plastic loop onto the BAP plate

A tale of two Staphs

BAP Hemolytic Reactions

Used with permission

Throat Swab

Used with permission

Catalase test

Positive negative

Coagulase test• Place a drop of the red latix suspension on

the card.

• Mix a tiny portion of the colony into the mix.

Things to Do Today

• Start gm (+) ID1. Direct stain with Crystal Violet

2. Check for hemolysis

3. Catalase test

4. Coagulase test

• Observe Throat cultures (Do in this order)1. Check for hemolysis

2. Catalase test and find cat (-) colony

3. Gm stain “isolated colonies” on slide with throat swab

BAP Hemolytic Reactions

Alpha hemolysis

Beta hemolysisgamma

Types of hemolysis:

A: Alpha or partial hemolysis of red blood cells results in a greenish zone

B: B-hemolysins, which produce complete breakdown of hemoglobin, causing clear zones to form around colonies on blood agar

A B