Leprosy

• Leprosy - Also known as Hansen's desease or Ketong
• Mycobacterium leprae - Causes a chronic disease called leprosy.
• Gerhard Armaeur Hanses

  • Discovered M. leprae in norway in 1873.
• Mycobacterium leprae

  • Obligate cellular
  • acid-fast, rod-shaped, slow growing
  • best in cool temperature
• Mode of transmission

  • Droplets
  • Prolonged close contact
• Pathogenesis of Leprosy

  1. Entry of Mycobacteium leprae inside Host body.
  2. Binds with the Schwann cell of PNS.
  3. Immune Response through cytokines by APS.
  4. Inhalation of Phagocytosis.
  5. Damage of Schwann Cells
• Skin Lesions

  • May appear as hypopigmented (light-colored) patches, erythematous (red) areas, or nodules on the skin.
• Peripheral Nerve Involvement

  • Leprosy affects peripheral nerves, leading to various neurological symptoms. 
  • This includes sensory loss, muscle weakness, and paralysis. 
  • Nerve damage can result in deformities of the hands, feet, and face, as well as loss of eyebrows and eyelashes.
• Ocular Manifestation

  • Corneal ulcer, staphyloma, blindness, and other eye complications can also occur if facial nerves are affected by the infection.
• Paucibacillary Case

  • A case of leprosy with 1 to 5 skin lesions, without demonstrated presence of bacilli in a skin smear.
• Multibacillary Case

  •  A case of leprosy with more than five skin lesions; or with nerve involvement (pure neuritis, or any number of skin lesions and neuritis); or with the demonstrated presence of bacilli in a slit-skin smear, irrespective of the number of skin lesions.
• Diagnosis of Leprosy

  • is confirmed by skin or nerve biopsy and acid-fast staining.
• Collection of specimen in leprosy

  • Skin smears
  • Skin biopsy
  • Nerve biospy
• Skin and Nerve Biopsy

  • It involves collecting small tissue samples from affected skin areas or nerves and looking for the presence of foam cells and characteristic histopathological changes associated with leprosy such as granulomas and inflammatory infiltrates.
• Acid Fast Staining

  • The Ziehl-Neelson method using 5% sulphuric acid as a decolorizing agent is used.
  • The presence of acid-fast bacilli confirms the diagnosis of Hansen’s disease.
• Duration of Treatment:

  • Paucibacillar (PB) Cases: 6 months.
  • Multibacillary (MB) Cases: 12 months.
• Contact Tracing

  • Identifying and locating individuals who have had close contact with a person diagnosed with leprosy.
• Preventive Chemotherapy

  • Administering a single-dose of rifampicin as a preventive chemotherapy to contacts of leprosy patients.