Lecture 15. Nonfermenting and Miscellaneous Gram-Negative Bacilli

Pseudomonas aeruginosa has a distincive:

• Blue-green pigmentation due to pyocyanin production (oil slick sheen)

• Fruity odor (grapes)

Pseudomonas aeruginosa is commonly associated with:

• Respiratory infections (Especially cystic fibrosis patients)

• Burn infections

• Bloodstream infections

What are the general characteristics in Acinetobacter species?

• Gram-negative

• Coccobacillus-shaped

• Non-motile

Which genus is resistant to decolorization during Gram staining, causing confusion in identification?

Acinetobacter

What are the general characteristics of Stenotrophomonas maltophilia?

• Gram-negative

• Rod-shaped

• Obligate aerobe

Stenotrophomonas maltophilia produces a distinct:

Ammonia-like odor

Stenotrophomonas maltophilia is capable of metabolizing:

Maltose

Stenotrophomonas maltophilia is resistant to:

Disinfectants

Genetically distinct but closely related species within the Burkholderia genus; difficult to distinguish without molecular testing

Burkholderia cepacia complex

Burkholderia cepacia complex is commonly seen in patients with:

Cystic fibrosis,w/ rapid deterioration, necrotizing pneumonia & septicemia. This condition is known as “cepacia syndrome”

Burkholderia pseudomallei causes:

Meliodosis - serious infectious disease endemic to SE Asia & Northern Australia

Burkholderia mallei causes:

“Glanders”, disease primarily affecting horses but can infect humans

What is the primary pathogenic species of Moraxella?

Moraxella catarrhalis

What are the general characteristics of Moraxella genus?

• Gram-negative

• Diplococcus-shaped

• Normal flora in the upper respiratory tract

Causes otitis media in children and exacerbation of COPD

Moraxella

Known for environmental resilience; can survive disinfectants & saline solutions:

Alcaligenes faecalis