test

• What is the shape of Mycobacteria?


  Unicellular and branched rods
• What type of bacteria are Mycobacteria classified as?


  Gram positive
• What is unique about the cell wall of Mycobacteria?


  It contains sugars, proteins, and a lot of lipid
• What staining method is used for Mycobacteria?


  Acid fast staining - Ziehl-Neelsen stain
• What is the primary stain used in the Ziehl-Neelsen method?


  Carbol fuchsin
• What is the purpose of destaining in the Ziehl-Neelsen method?


  To remove excess stain from non-acid fast bacteria
• What color do Mycobacteria appear after the Ziehl-Neelsen staining process?


  Red
• What color do non-Mycobacteria appear after the Ziehl-Neelsen staining process?


  Blue
• How are Mycobacteria grouped?


  • Fast growers: 1-2 days on plates (e.g., *M. phlei*, *M. smegmatis*)
  • Slow growers: several weeks
  • Most are saprophytes; major pathogens are slow growers
• Which Mycobacterium is closely related to tuberculosis?


  *M. bovis*
• What is the *M. avium-intracellulare* complex associated with?


  Animal pathogens and opportunists, common with HIV
• What type of pathogen is *M. paratuberculosis*?


  Ruminant pathogen
• What disease is caused by *M. ulcerans*?


  Buruli ulcer
• What is the causative agent of leprosy?

  *Mycobacterium leprae*
• What disease does *M. marinum* cause?


  Disease of fish, frogs, and humans
• Why is tuberculosis considered a global emergency?


  30,000 die every week and 2 billion people are infected
• What is a significant risk factor for tuberculosis infection?


  High incidence in HIV infected individuals
• What are the general clinical manifestations of tuberculosis?


  • Fever
  • Weight loss
  • Weakness
  • Persistent cough
  • Result from inflammatory response
• What type of infection is tuberculosis primarily classified as?


  A pulmonary infection
• How can tuberculosis spread beyond the lungs?


  It may spread to the central nervous system, lymphatic system, genitourinary systems, bones, and joints
• What is the term for the spread of tuberculosis throughout the body?

  Disseminated (miliary TB)
• How does tuberculosis typically enter the body?


  Through aerosol that travels to the alveoli of the lungs
• What happens to *M. tuberculosis* once it reaches the alveoli?


  It is engulfed by alveolar macrophages
• What can happen if the immune response is activated against *M. tuberculosis*?


  The host may clear the bacteria or at least contain the infection
• What occurs if the immune response is inactivated?


  The bacteria survive and replicate in macrophages
• What is formed as a result of the immune response to *M. tuberculosis*?


  A granulomatous tubercle
• What can happen to a granuloma over time?


  It may remain walled off for years to decades, then allow release of viable bacteria
• What is required for the clinical syndrome of tuberculosis to manifest?


  An intact immune response
• How does the inflammatory response correlate with tuberculosis?


  It correlates with the degree of cavitation
• How does late-stage HIV affect the infectivity of pulmonary tuberculosis (PTB)?


  It decreases the infectivity
• What effect do steroids have on sputum clearance in tuberculosis patients?


  They increase the rate of sputum clearance
• What is required for the transmission of tuberculosis?


  The immune response
• What are the methods for diagnosing tuberculosis?

  • Radiology
  • Microscopy of sputum for acid fast rods
  • Culture of sputum samples on specific media
  • PCR
  • Immunological tests for T cell response
• What are the control measures for tuberculosis?


  • Preventative vaccination
  • Immunization prior to exposure
  • Antibiotic treatment for active or latent TB
• What is the name of the vaccine used for tuberculosis?

  Bacille Calmette-Guerin (BCG)
• What is the origin of the BCG vaccine?


  Derived from *M. bovis* by serial passage
• What are the characteristics of the BCG vaccine?


  It is avirulent, effective in experimental models, safe, and inexpensive
• How many doses of BCG are given per year globally?


  100 million doses
• What is the treatment regimen for tuberculosis?


  • Multi-drug treatment required due to resistance
  • First line oral anti-TB drugs for 6 months:
  • Isoniazid
  • Rifampicin
  • Ethambutol
  • Pyrazinamide
• What does MDR-TB stand for?


  Multi-drug resistant tuberculosis