Mycobacteria

• What is the shape of Mycobacteria?

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

  Gram positive
• What is a key feature of the Mycobacteria cell wall?

  It contains sugars, proteins, and a lot of lipid

  
• What staining method is used for Mycobacteria?

  Acid fast staining using Ziehl Neelson stain

  
• What color do Mycobacteria appear after acid fast staining?

  Red

  
• What is the purpose of counterstaining with methylene blue in acid fast staining?

  To differentiate Mycobacteria from other cells

  
• How are Mycobacteria grouped based on their growth rates?

  • FAST growers: 1-2 days on plates (e.g., M.phlei, Msmegmatis)
  • SLOW growers: several weeks (e.g., M.tuberculosis)

  
• Which Mycobacterium is closely related to tuberculosis?

  1. bovis
• What is the common name for M.ulcerans?

  Buruli ulcer
• What is the global impact of tuberculosis in terms of mortality?

  30,000 die every week
• How many people are infected with tuberculosis globally?

  2 billion people
• Why is tuberculosis considered a disease of poverty?

  It has a high incidence in HIV infected individuals
• What are the general clinical manifestations of tuberculosis?

  • Fever
  • Weight loss
  • Weakness
  • Persistent cough
• What is the primary infection site for tuberculosis?

  The lungs
• What happens when M. tuberculosis is engulfed by alveolar macrophages?

  It can either be cleared or replicate depending on the immune response
• What is a granulomatous tubercle?

  A structure formed when bacteria attract more immune cells and damage tissue
• What can happen to a tubercle over time?

  It can remain silent or allow reactivation of bacteria

  
• What is the effect of steroids on sputum clearance in tuberculosis patients?

  They increase the rate of sputum clearance
• What are the methods for diagnosing tuberculosis?

  • Radiology
  • Microscopy of sputum for acid fast rods
  • Culture of sputum samples
  • PCR

  
• What is the purpose of preventive vaccination against tuberculosis?

  To prevent establishment of infection and disease development

  
• What is the name of the vaccine used for tuberculosis?

  Bacille Calmette-Guérin (BCG)
• What is the efficacy of BCG vaccine in humans?

  It protects against disseminated disease in children
• What are the first-line oral anti-TB drugs?

  Isoniazid, Rifampicin, Ethambutol, Pyrazinamide

  
• What is the treatment regimen for multi-drug resistant tuberculosis (MDR-TB)?

  At least 4 potentially active drugs

  
• What is the causative agent of leprosy?

  Mycobacterium leprae
• Why is the transmission of leprosy still a mystery?

  Most people who contact leprosy patients do not get infected
• What are the two clinical manifestations of leprosy?

  • Tuberculoid: mild disease with few bacilli and strong immune response
  • Lepromatous: severe disease with many bacilli and poor immune response
• What is the most used antibiotic for leprosy treatment?

  Dapsone
• What is the challenge with Dapsone in leprosy treatment?

  Resistance to Dapsone is becoming increasingly common
• What is the recommended treatment for leprosy?

  • Multidrug therapy: Dapsone, Clofazamine, Rifampicin
• What are the key points about tuberculosis treatment regimens?

  • Multi-drug treatment required due to resistance
  • WHO updates recommendations yearly