Leprosy Flashcards
Reservoir of leprosy
Humans
Armadillo
Risk factors for leprosy
Low level of education
Poor hygiene
Food shortages
Most important risk factor
Intimacy and duration of contact with leprosy patients
Morphologic index
A measure of uniformly stained solid bacilli on slit-skin smear examination.
Calculated as percentage of viable bacilli among the total number of bacilli counted under oil-immersion microscopy
Bacteriologic Index
A logarithmic-scaled measure of the density of bacilli of all forms found in the dermis upon slit-skin smear examination
Approach to diagnosis of
leprosy
Clinical diagnosis - 2 out of 3:
- Hypopigmented or erythematous skin lesion/s with definite loss or impairment of sensation
- Involvement of peripheral nerves demonstrated by definite thickening with sensory impairment
- Positive AFB
- positive AFB in slit-skin smears
-presence of AFB in a skin smear or biopsy sample
-Positive result in biopsy PCR
WHO Classification of leprosy
Modes of transmission
- Shed in large members from the mouth and nose of patients with untreated multibacillary leprosy (droplet infection)
- From damaged skin
- Human-to-human transmission
- Zoonotic transmission through wild armadillos
- Enters the body through the respiratory tract or through skin (wounds or tattoos)
Various spectrum of leprosy based on clinical , bacteriologic, pathologic, and immunologic parameters
Tuberculoid leprosy
Lepromatous leprosy
Comprise several common immunologically mediated inflammatory states that cause considerable morbidity
Lepra reactions
occur in almost half of patients with borderline forms of leprosy but not in patients with pure lepromatous disease
Type 1 Lepra reactions
Classic signs of Type 1 Lepra Reactions
Inflammation within previously involved macules, papules and plaques, and on occasion, the appearance of new skin lesions, neuritis, and fever
Nerve trunk most frequently involved in Type 1 lepra reaction
ulnar nerve at the elbow