Genus Chlamydia: C. trachomatis, C. psittaci, C. pneumoniae

• What is the morphology of Chlamydia bacteria?

  Small, round-ovoid bacteria
• What is absent in the cell wall of Chlamydia?

  Muramic acid
• What can be seen on a Giemsa stain of Chlamydia?

  Cytoplasmic inclusion bodies
• What type of medium does Chlamydia require for culture?

  Tissue medium
• Why are Chlamydia bacteria classified as obligate intracellular bacteria?

  They are unable to produce ATP
• What are the two stages of the Chlamydia life cycle?

  1. Elementary Stage - infectious form
  2. Reticular Body - active dividing form
• What are the three main strains of Chlamydia?

  Chlamydia Trachomatis, Psittaci, Pneumoniae
• What is the reservoir for Chlamydia Trachomatis?

  Genitourinary Tract
• Which birds are reservoirs for Chlamydia Psittaci?

  Parrots and other birds
• What is the reservoir for Chlamydia Pneumoniae?

  Humans
• How is Chlamydia Trachomatis transmitted?

  • Sexual contact
  • Vaginal birth
  • Hand-to-eye
  • Flies
• How is Chlamydia Psittaci transmitted?

  • Inhalation of contaminated dust
  • Respiratory secretions or faeces of infected birds
• How is Chlamydia Pneumoniae transmitted?

  • Aerosol transmission
• What are the virulence factors of Chlamydia?

  • Major Outer Membrane Protein (MOMP)
  • Polymorphic Outer Membrane Protein (PMP)
  • Cytotoxin
  • Lipopolysaccharide (LPS)
• What is the function of Major Outer Membrane Protein (MOMP)?

  Protective surface antigens
• What does Polymorphic Outer Membrane Protein (PMP) elicit?

  Proinflammatory cytokine responses
• What does the cytotoxin of Chlamydia cause?

  Actin reorganization
• What is Lipopolysaccharide (LPS) composed of?

  O antigen and lipid A
• What does LPS trigger in the immune response?

  Macrophage, complement, and tissue factor activations
• What are the methods for microbiological diagnosis of Chlamydia?

  • Microscopy with Giemsa stain
  • NAAT (Nucleic-Acid Amplification Test)
• What is the microscopy method used for Chlamydia diagnosis?

  Giemsa stain
• What is observed under the microscope using Giemsa stain?

  Cytoplasmic inclusions within cells
• What are the treatments for Chlamydia infections?

  Doxycycline or Macrolides
• What is the prevention method for conjunctivitis caused by Chlamydia?

  Erythromycin eye drops