Leprosy

clinical picture

• manifests in skin and peripheral nerves
• papule, macule, plaque, hypopigmentation, nodule
• loss of sensation, paralysis, amyotrophy
• incubation months to >30 years

Ridley-Jopling classification

• TT - tuberculoid
• BT - borderline tuberculoid
• BB - borderline borderline
• BL - borderline lepromatous
• LL - lepromatous

• TT direction - abnormal or significant immune response (granulomatous) against few M. leprae bacilli
  • PB in WHO classification
  • infiltrated plaque
  • well-defined, sharp border
  • single skin lesion
  • localized, asymmetrical
  • loss of sensation at skin lesion
    • in histopathology nerves are surrounded by granuloma
• LL direction - least cellular immunity or allergic reaction against much amount of M. leprae bacilli
  • MB in WHO classification
  • macule, papule, nodule
  • multiple skin lesion
  • widespread, symmetrical
  • loss of sensation at ...
    • in histopathology diffuse infiltrate of foamy histiocytes (macrophages) in dermis
    • Leonine facies: madarosis, saddle nose

diagnosis

• WHO criteria: one or more cardinal signs

1. skin lesion consistent with leprosy with definite sensory loss
2. thickened nerve, peripheral neuropathy
3. skin smear...

treatment

• MB >5 lesions
• PB 1-5 lesions

leprosy reaction

• can develop at anytime on clinical course
  • either before or after commencement of treatment
  • even after completion of treatment
• incidence 20-60% in multiple studies

• Type 1 reversal reaction
  • cell-mediated delayed hypersensitivity
  • reddish, swollen, warm, painful, tender
  • systemic condition fair
• Type 2 erythema nodosum leprosum (ENL)
  • antigen-antibody immune complex reaction
  • multiple, distributed bilaterally and symmetrically
  • with high grade fever and malaise

treatment of leprosy reaction

• antipyretics, NSAIDs
• steroid
• immunosuppressant