Leprosy

Filename: Leprosy.ppt

Outline

• Organism

• Clinical findings

• Diagnosis

• Treatment

• Epidemiology

• Prevention and control

Mycobacterium leprae

• Unable to cultivate

• Smears & scrapings
  • Acid fast rod
  • Single, parallel bundles, masses

• Intracellular
  • endothelial cells of blood vessels
  • nerves
  • mononuclear cells

Endothelial cells

• Grows in the endothelial cells of the blood vessels

Intracellular Growth in Superficial Nerves

Nerve

Experimental models

• Mice
  • Foot pads
  • local granulomatous lesion
  • limited multiplication

• Armadillo
  • quadruplets

Lepromin Skin Test

• Analogue of tuberculin test

• Extract of macular lesions

• Inject subdermally

Clinical findings

• Cooler tissues of body
  • skin, superficial, nerves, noses, larynx eyes and testicles

Types of Leprosy

• Lepromatous

• Tuberculoid

Lepromatous Leprosy

• Progressive but slow

• malign

• nodular skin lesion

• Symmetric nerve involvement

• many acid fast bacilli

• Positive lepromin test

Tuberculoid Leprosy

• Non progressive

• Benign

• Macular skin lesions

• Asymmetric nerve involvement

• Few acid fast bacilli

• Lepromin negative

Eye Involvement

Skin Lesions

• Pale

• Macular lesion 1-10 cm

• anaesthetic

Neurological involvement

• Nerve infiltration & thickening
  • anaesthesia
  • neuritis

• Causes
  • Trophic ulcers
  • Bone Reabsorption
  • shortening of Digits

Trophic ulcers

Bone Reabsorption

Shortening of Digits

Diagnosis

• Clinical findings

• Scrapings Acid fast bacilli

• Biopsy
  • Nerve involvement

• Lepromin test

Tests for syphilis false positive

Treatment

• Special sulfones
  • Dapsone (diaminodiphenylsufone)

• Rifampin

• Long term treatment
  • Months- years

Epidemiology

• Mode of transmission ???

• Children most susceptible
  • Contracted from close family members

• Very long term incubation period

• Onset as adults

Prevention & Control

• Separate patients & young children in family

• Chemotherapy of patients & family

• BCG vaccination

The End

Performance Objectives

Key terms, concepts

short answers

Key Terms

Key Terms

Key Organisms

Key Concepts

Epidemiology of ???

• Disease/bacterial factors

• Transmission

• Who is at risk

• Geography/ season

• Incidence

• Modes of control

Short Answers

• Construct a table of the virulence factors associated with ??? and the biological activity of each

• Describe the clinical manifestations of ???

• Construct a table listing the common ??? species and the associated human diseases.