Non-Fermentative Bacilli: Characteristics and Pathogenesis

Non-Fermentative Bacilli

Pseudomonas aeruginosa Characteristics

• Gram-negative, aerobic, rod-shaped bacterium
• Found in soil, water, and human gut
• Opportunistic pathogen, causing infections in immunocompromised individuals
• Produces blue-green pigment pyocyanin, which has antimicrobial properties
• Can form biofilms, making it resistant to antibiotics and host immune system

Stenotrophomonas maltophilia Pathogenesis

• Opportunistic pathogen, often affecting immunocompromised individuals
• Causes a range of infections, including pneumonia, bacteremia, and urinary tract infections
• Produces a variety of enzymes, including proteases, lipases, and DNases, which contribute to its pathogenesis
• Can form biofilms, making it resistant to antibiotics and host immune system

Acinetobacter baumannii Drug Resistance

• Multidrug-resistant, with high levels of resistance to antibiotics, including carbapenems and aminoglycosides
• Resistance mechanisms include:
  • Production of beta-lactamases, which break down antibiotics
  • Alterations in porin proteins, reducing antibiotic uptake
  • Activation of efflux pumps, which remove antibiotics from the cell
• High mortality rates associated with A. baumannii infections, particularly in intensive care units

Non-Fermentative Gram-Negative Bacilli

• Group of bacteria that do not ferment glucose, including Pseudomonas, Stenotrophomonas, and Acinetobacter
• Characterized by their ability to oxidize glucose, rather than fermenting it
• Often associated with nosocomial infections, particularly in immunocompromised individuals

Hospital-Acquired Infections

• Non-fermentative bacilli are common causes of hospital-acquired infections, including:
  • Pneumonia
  • Urinary tract infections
  • Bacteremia
  • Wound infections
• Often associated with the use of medical devices, such as ventilators and catheters
• Can be difficult to treat due to high levels of antibiotic resistance

Burkholderia cepacia

• Gram-negative, aerobic bacterium
• Found in soil and water, and can colonize human respiratory tract
• Can cause chronic infections, particularly in individuals with cystic fibrosis
• Produces a variety of enzymes, including proteases and lipases, which contribute to its pathogenesis
• Can be resistant to multiple antibiotics, making treatment challenging