Nonfermenting Gram Negative Bacilli

Non-fermenters are usually oxidase (+/-).

+

What 2 non-fermenters are oxidase -?

1. Stenotrophomonas maltophilia

2. Acinetobacter baumanii

Many non-fermenters are:

• obligate aerobes

• obligate anaerobes

• facultative aerobes

• capnophiles

obligate aerobes (need O2)

O/F media contains low concentrations of ________ with glucose to determine if an organism can use the carbohydrate oxidatively, fermentatively, or not at all.

peptones

What is the pH indicator in O/F media?

bromthymol blue

The tubes on the left contain a:

• oxidizer

• fermenter

• non-oxidizer

fermenter

The tubes in the middle contain a:

• oxidizer

• fermenter

• non-oxidizer

oxidizer

The tubes on the right contain a:

• oxidizer

• fermenter

• non-oxidizer

non-oxidizer

What 5 non-fermenters are oxidizers in O/F media?

(Penguins Slide Across Blue Ice)

1. Pseudomonas aeruginosa

2. Stenotrophomonas maltophilia

3. Acinetobacter baumanii

4. Burkholderia cepacia

5. Elizabethkingia meningoseptica

The most common non-fermenting GNR isolated in the lab will be what highly resistant organism?

Pseudomonas aeruginosa

Flo and Tech agar is used to differentiate the non-fermenter: __________________. Flo agar is used to detect _________, producing a fluorescent yellow-green pigment black light. Tech agar is used to detect _________, producing a blue-green pigment.

Pseudomonas aeruginosa, pyoverdin, pyocyanin

Besides pyoverdin and pyocyanin, Pseudomonas aeruginosa can produce __________, giving off a rust-red pigment and _________, giving off a brown pigment.

pyorubin, pyomelanin

What non-fermenter appears metallic on SBA and has a unique green pigment on MAC?

Pseudomonas aeruginosa

What non-fermenter grows between 20-42C and gives off a grape-like odor?

Pseudomonas aeruginosa

The most important virulence/invasiveness factor for Pseudomonas aeruginosa is that it produces:

exotoxin A

What non-fermenter causes keratitis (destruction eye infection), Swimmer’s ear, and chronic lung infections?

Pseudomonas aeruginosa

What non-fermenter has a lavender/green color on SBA and gives off an ammonia-like odor?

Stenotrophomonas maltophilia

What non-fermenter has increased incidences of infection in immunocompromised patients and following antibiotic therapy?

Stenotrophomonas matlophilia

What non-fermenter has grayish-white sticky colonies on SBA and colorless or pinkish-blue colonies on MAC?

Acinetobacter baumanii

What coccobacillus non-fermenter is often in pairs when Gram stained and has a fishy odor?

Acinetobacter baumanii

What non-fermenter causes nosocomial pneumonia following respiratory therapy?

Acinetobacter baumanii

What non-fermenter produces yellow colonies on SBA and is weakly oxidase positive?

Burkholderia cepacia

What non-fermenter causes lung abscesses and can indicate a poor prognosis in cystic fibrosis patients?

Burkholderia cepacia

What non-fermenter produces lavender-green colonies on SBA with no distinct odor?

Elizabethkingia meningoseptica

What non-fermenter causes meningitis in neonates?

Elizabethkingia meningoseptica

What 3 non-fermenters are non-oxidizers in O/F media?

(Meerkats Explore Africa)

1. Moraxella species

2. Eikenella corrodens

3. Alcaligenes faecalis

What non-fermenter grows tiny colonies that can indent on SBA and has no distinct odor?

Moraxella species

What non-fermenter is part of our respiratory and GU tracts’ normal flora and causes conjunctivitis?

Moraxella species

What non-fermenter grows tiny colonies that can indent and corrode the SBA and has bleach-like odor?

Eikenella corrodens

What non-fermenter that is part of our normal oral flora causes infections through human bite wounds and facial neck abscesses?

Eikenella corrodens

What non-fermenter produces feathered edge colonies on SBA and gives off a fruit/apple-like odor?

Alcaligenes faecalis

What non-fermenter causes otitis media and ear discharge?

Alcaligenes faecalis