What are examples of Gram-negative bacilli?

From the Guidelines

Gram-negative bacilli are a group of rod-shaped bacteria that include Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Salmonella species, Haemophilus influenzae, Proteus species, Enterobacter, Serratia, Acinetobacter, and Legionella pneumophila, which are clinically important due to their ability to cause various infections and possess intrinsic resistance to multiple antibiotics. These bacteria are characterized by their thin peptidoglycan layer and outer lipopolysaccharide membrane, which makes them resistant to certain antibiotics. According to the most recent study 1, the extensive spread of carbapenem-resistant Gram-negative bacilli has become a global public health issue, with carbapenem-resistant Enterobacteriales, carbapenem-resistant Acinetobacter baumannii, and carbapenem-resistant Pseudomonas aeruginosa being identified as pathogens of critical threat.

Some key points to consider when dealing with gram-negative bacilli include:

• Their ability to develop resistance to commonly used antibiotics, making treatment challenging 1
• The importance of considering local resistance patterns when selecting antibiotics for treatment 1
• The need for specific antibiotics, such as carbapenems, aminoglycosides, or newer agents, depending on susceptibility testing 1
• The potential for these bacteria to produce enzymes like beta-lactamases that inactivate many common antibiotics 1
• The clinical significance of these bacteria in causing various infections, including urinary tract infections, pneumonia, and meningitis 1
• The importance of proper infection control measures to prevent the spread of these bacteria in healthcare settings 1

From the FDA Drug Label

Aerobic gram-negative microorganisms Campylobacter jejuni Proteus mirabilis Citrobacter diversus Proteus vulgaris Citrobacter freundii Providencia rettgeri Enterobacter cloacae Providencia stuartii Escherichia coli Pseudomonas aeruginosa Haemophilus influenzae Salmonella typhi Haemophilus parainfluenzae Serratia marcescens Klebsiella pneumoniae Shigella boydii Moraxella catarrhalis Shigella dysenteriae Morganella morganii Shigella flexneri Neisseria gonorrhoeae Shigella sonnei

Examples of gram-negative bacilli include:

• Enterobacteriaceae:
  • Escherichia coli
  • Klebsiella pneumoniae
  • Enterobacter cloacae
  • Citrobacter freundii
  • Proteus mirabilis
  • Proteus vulgaris
• Pseudomonadaceae:
  • Pseudomonas aeruginosa
• Neisseriaceae:
  • Neisseria gonorrhoeae
• Other gram-negative bacilli:
  • Haemophilus influenzae
  • Haemophilus parainfluenzae
  • Moraxella catarrhalis
  • Campylobacter jejuni
  • Salmonella typhi
  • Serratia marcescens
  • Shigella boydii
  • Shigella dysenteriae
  • Shigella flexneri
  • Shigella sonnei 2

From the Research

Examples of Gram-Negative Bacilli

• Escherichia coli (E. coli) 3, 4, 5, 6
• Klebsiella pneumoniae 3, 7, 4, 5, 6
• Pseudomonas aeruginosa 3, 7, 4, 5, 6
• Acinetobacter baumannii 3, 7, 5
• Enterobacter spp. 3, 4, 5, 6

Characteristics of Gram-Negative Bacilli

• Often exhibit antibiotic resistance 3, 7, 6
• Can cause a range of infections, including bacteremia, pneumonia, and urinary tract infections 4, 5, 6
• Can be associated with high mortality rates, particularly in hospitalized patients 7, 6