Pseudomonas

• What is Pseudomonas aeruginosa commonly found in?

  Soil and water
• Why is Pseudomonas aeruginosa recognized as an emerging opportunistic pathogen?

  It has increasing antibiotic resistance and is a nosocomial pathogen
• What is the taxonomic classification of Pseudomonas aeruginosa?

  Domain: Bacteria, Phylum: Proteobacteria, Class: Gamma proteobacteria
• What pigments does Pseudomonas aeruginosa produce?

  Pyocyanin (blue) and pyoverdin (green)
• Where is Pseudomonas aeruginosa commonly detected in inanimate environments?

  Water-reservoirs, sewage, and sinks
• What is the gastrointestinal carriage rate of Pseudomonas aeruginosa in hospitalized patients?

  20% within 72 hours of admission
• How does Pseudomonas aeruginosa spread in a hospital environment?

  Through contaminated hands, direct contact, and ingestion of contaminated food and water
• What demographic is primarily affected by Pseudomonas aeruginosa endocarditis in IV drug users?

  Young black males
• What is the male-to-female ratio for Pseudomonas aeruginosa endocarditis cases?

  1. 4:1
• In which patients is pseudomonal pneumonia most commonly observed?

  Patients with cystic fibrosis
• What are the general characteristics of Pseudomonas aeruginosa?

  Aerobic, non-spore forming, Gram-negative rod
• What is the optimum temperature for the growth of Pseudomonas aeruginosa?

  37 degrees Celsius
• What are the virulence factors of Pseudomonas aeruginosa?

  Flagella, pili, exopolysaccharide alginate, and exotoxins
• What role does exopolysaccharide alginate play in Pseudomonas aeruginosa's virulence?

  It impairs antibiotic action
• What is the effect of exotoxin A produced by Pseudomonas aeruginosa?

  It causes tissue necrosis and disrupts protein synthesis
• What is the primary mechanism of colonization by Pseudomonas aeruginosa?

  Adherence to epithelial cells via pili and proteases
• How do elastase and alkaline protease contribute to Pseudomonas aeruginosa's virulence?

  They cleave collagen and disrupt respiratory epithelium
• What is a common ocular infection caused by Pseudomonas aeruginosa?

  Bacterial keratitis
• What predisposing conditions can lead to Pseudomonas aeruginosa infections in the eye?

  Trauma, contact lens use, and exposure to ICU environments
• What is the primary cause of otitis externa associated with Pseudomonas aeruginosa?

  Injury, inflammation, or wet conditions
• What are the symptoms of malignant otitis externa?

  Persistent pain, edema, and purulent discharge
• What is green nail syndrome associated with?

  Paronychial infection in individuals with wet hands
• What are the gastrointestinal effects of Pseudomonas aeruginosa in immunocompromised patients?

  Severe necrotizing enterocolitis and pseudomonal diarrhea
• How does Pseudomonas aeruginosa cause bacteremia and septicemia?

  Primarily in immunocompromised patients, often acquired in hospitals
• What is a common respiratory infection caused by Pseudomonas aeruginosa?

  Pneumonia in patients with chronic lung disease
• What is the role of mucoid strains of Pseudomonas aeruginosa in cystic fibrosis patients?

  They cause lower respiratory tract colonization
• What are the key characteristics of Pseudomonas aeruginosa?

  • Free-living bacterium
  • Ubiquitous in soil and water
  • Opportunistic pathogen
  • Increasing antibiotic resistance
  • Aerobic, non-spore forming, Gram-negative rod
  • Produces pigments like pyocyanin and pyoverdin
• What are the stages of pathogenesis for Pseudomonas aeruginosa?

  1. Attachment and colonization
  2. Local infection
  3. Bloodstream dissemination and systemic disease
• What are the common clinical infections caused by Pseudomonas aeruginosa?

  • Bacterial keratitis
  • Otitis externa
  • Pseudomonal pneumonia
  • Endocarditis
  • Gastrointestinal infections
• What are the common laboratory identification methods for Pseudomonas aeruginosa?

  • Culture on selective media
  • Oxidase test
  • Identification of characteristic pigments
  • Biochemical tests for metabolic properties
• What are the treatment options for Pseudomonas aeruginosa infections?

  • Antibiotic therapy (e.g., piperacillin, ceftazidime)
  • Combination therapy for resistant strains
  • Supportive care for severe infections
• What are the prevention and control measures for Pseudomonas aeruginosa infections?

  • Strict hygiene practices in healthcare settings
  • Proper disinfection of medical equipment
  • Monitoring and controlling water sources
• What are the implications of Pseudomonas aeruginosa in immunocompromised patients?

  • Increased risk of severe infections
  • Higher rates of morbidity and mortality
  • Need for aggressive treatment and monitoring
• What are the possible symptoms of Pseudomonal diarrhoea?

  Irritability, vomiting, diarrhea, and dehydration
• What condition can occur in patients with neutropenia due to acute leukemia?

  Typhilitis with sudden onset of fever, abdominal distension, and worsening abdominal pain
• What percentage of hospital-acquired Gram-negative bacteremias is accounted for by Pseudomonas infections?

  About 25%
• How does Pseudomonas aeruginosa invade the central nervous system?

  From a contiguous structure, head trauma, surgery, or distant site infection
• What type of patients are primarily affected by endocarditis caused by Pseudomonas aeruginosa?

  IV drug users and patients with prosthetic heart valves
• In which patients does primary pneumonia caused by Pseudomonas aeruginosa commonly occur?

  Patients with chronic lung disease and congestive heart failure
• What is a common complication of cystic fibrosis related to Pseudomonas aeruginosa?

  Lower respiratory tract colonization by mucoid strains