leprosy (hansen’s disease). causative organism- mycobacterium leprae affects mainly cooler parts...
TRANSCRIPT
LEPROSY (Hansen’s Disease)
• Causative Organism- Mycobacterium
leprae
• Affects mainly cooler parts of the body
• Skin, mouth, Respiratory Tract, eyes,
Peripheral nerves, Testis, etc
• Earliest --------Skin & Nerves
PATHOGENESIS Acid fast, obligate intracellular organism
Poor growth in culture, but grows in
armadillo, foot pad of mice
Virulence– cell wall properties
Cell mediated immunity– Lepromin Test
DIAGNOSIS
Split skin smears & nasal smears
AFB ( Ziehl – Neelson) stain
Fite Faraco Stain
Silver stain
• Bacteriological Index
• Morphological Index
Solid staining – Live
Fragmented / Beaded - Dead
• Paucibacillary – No Bacilli
• Multibacillary – Some or many Bacilli
TRANSMISSION
• ? Inhalation
• Direct Contact
• Maternofetal transmission
Classification
2 Main types ( polar forms);
a) Lepromatous – Low Immunity
b) Tuberculoid – High Immunity
Modified Ridley Jopling’s Classification• Indeterminate
• TT – Tuberculoid
• BT – Borderline Tuberculoid
• BB – Mid Borderline
• BL – Borderline Lepromatous
• LL -- Lepromatous
FEATURES TT LL
Skin Lesions Asymmetrical Symmetrical (Leonine Facies)
Nerve Involvement +, Sensory disturbance ++
Sensory disturbance
Foam Cells, ‘Grenz Zone’ +
Microscopy Tubercle, ‘Grenz Zone’ -ve
Bacilli load ‘Globi’ / cigarette pack
Few are seen
Immunity High Low
Lepromin Test + -
Tuberculoid Leprosy:• Skin lesions
• Nerve lesionsAnaesthesia, Skin & muscle atrophy, Trophic ulcers, Contractures,etc
• MC – Ulnar, Radial, Common peroneal
• VII Cranial nerve Keratitis, Corneal ulcer
Lepromatous Leprosy:
• Widespread invasion of shwann cells, neural macrophages
• GlobiAggregates of foam cells filled with masses of AFB
• Macules, Papules,Nodules Leonine Facies
• Testes- Extensive destructionSterility
REACTIONS IN LEPROSY
Type I ( Reversal Reaction)• Upgrading Reaction• Downgrading Reaction
Type II ( Erythema Nodosum Leprosum)• Usually after chemotherapy• Occurs in LL• Tender nodules, Iridocyclitis, Lymph node involvement• Infiltration of neutrophils, Vasculitis• Responds to Treatment