Day 2: Things I Forget

Question 1

What are the five possible enterobacters?

Answer 1

Citrobacter freundi

Enterobacter cloacae

Escherichia Coli

Klebsiella pneumoniae

Proteus mirabilis

Question 2

How can you identify citrobacter freundi from the biochemical tests?

Answer 2

Its a lactose fermenter where by all the bijous (everything excluding citrate) is negative bar for methyl red

i.e. a lactose fermenter whereby all reactions bar methyl red and citrate are negative

Question 3

How can you identify enterobacter cloacae?

Answer 3

Its a lactose fermenter where by all the bijous are negative bar for voges-proskouer

i.e. a lactose fermenter whereby all reactions bar vogues proskouer and citrate are negative

Question 4

How can you identify escherichia coli

Answer 4

Only organism whereby indole is positive

Only organism whereby citrate is negative

Question 5

How can you identify klebsiella pneumonia

Answer 5

The only lactose fermenter where urease is positive

Question 6

How can you identify proteus mirabilis

Answer 6

Its the only non lactose fermenter studied

Its a non lactose fermenter with a positive vogues proskouer

Question 7

What are the substrates involved in the VP reaction colour production?

Answer 7

Acetoin and 2,3-butanediol react with a-naphthol to produce a mahogany red colour

Question 8

What is a positive phenylalanine test

Answer 8

Blue-green colour complex formation

Question 9

What is a negative phenylalanine test

Answer 9

Straw colour

Question 10

List the eight organisms examined with the MID8 Mastring test

Answer 10

B. fragilis
B. oralis
B. ureolyticus
F. mortiferum
Pr. melaninogenica
F. necrophorum
GPC
GNC

Question 11

What antibiotics are used in the calvulanic acid ESBL combination disc test?

Answer 11

Cefotaxime
Ceftazidime

+ clavulanic acid discs