Leprosy Flashcards
Chronic infection of nerves with skin manifestation
Leprosy
also known as Hansen’s disease
According to WHO, the following groups are considered to have cases of leprosy
Persons having one or more of the following:
Hypopigmented or reddish skin lesions with loss of sensation
Involvement of peripheral nerves
Skin smear positive for acid fast bacilli
Incubation Period of hansen’s disease
5 years (6 months to 20 years)
has a subclinical stage where immunity must weaken before any lesion
Mode of transmission for Leprosy:
Droplet transmission
Susceptibility in Leprosy
Most people are actually only mildly susceptible
Factors:
Genetic
Repeated exposure
Etiology of Hansen’s disease
Mycobacterium leprae
Mycobacterium leprae
slow-growing
Doubling time of 2 weeks
Does not grow in culture media
Prefers cooler temp (27-35)
The clinical immunologic Spectrum Leprosy
Cell mediated Immunity
Antibody response
Cell Mediated Immunity
In the first phase; T cells and macrophages are the ones that respond to the bacteria
The T cells and macrophages are what we need to kill and contain bacteria
The T cells and a granulomatous reaction in the body if the cell-mediated immunity isn;t enough
Antibody Response
T cell response weakens and becomes an antibody-dominant response
strong AB response but useless
These AB cannot kill the bacteria therefore, this phase leads to more extreme cases of leprosy
Indeterminate Leprosy
some cases may resolve, while some may progress to full term
Patches may have loss sensation and when biopsied may have granulomatous infiltrates
Ill defined patch
Single or few, assymetrical, well defined hyppigmented, erythematous or copper colored patches with raised borders
no satellite lesion
Tuberculoid leprosy
Few, asymetrical, well demarcated, dry plaques. May be annular with clearly defined outer borders. Surface may be scaly
Bordeline TL
More numerous lesions than TL (>3 and <10 lesions)
Asymmetrical, less well demarcated, shiny plaques, often annular with sharply-marginated inner and outer borders
Mid borderline Leprosy
Numerous (>5) smaller,, rougly symmetrical, shiny, macules, papules, nodules, and plaques with sloping edges
Annular punched out lesions
Bordeline Lepromatous Leprosy
Very numerous, symmetrically distributed, erythematous or sopper colored, shiny macules
Presents with a lot of infiltration on the skin
LL
Classifies cases of leprosy bases on clinical features
Ridley Jopling classification
WHO classification of leprosy
Multibacillary
Paucibacillary
Multibacillary Leprosy
> 5 skin lesions
+ AFB
1 nerve trunk involves
Paucibacillary Leprosy
<5 skin lesions
NO AFB in skin smears
0-1 Nerve trunks involved
MB - Ripley-jolling
Lepromatous
BL
BT
PB- Ripley jopling
BT
T
Indertimate
“Leprary reactions”
Cured persons with late reactions
Cured persons with residual disabilities
2 nervess usually examined in Leprosy
Ulnar and common peroneal
Diagnostic test of leprosy
Slit skin smear
Skin biopsy
MDT of Lprosy
Rifampicin
Clofazimine
Dapsone
A leprosy patient becomes non-infectious after taking MDT for _______ month
1 month
Treatment for PB leprosy (Indeterminate, TT, BT)
Rifampicin 600mg once a month for 6 months
+
Dapsone 100 mg daily for 6 months
Treatment for MB Leprosy( BT, BB, BL, LL)
Rifampicin 600 mg and Clofazimin 300 mg once a month
+
Dapsone 100mg and clofazimine 50 mg for 12 months or until skin smears show no more solid staining Bacilli
Side effects for treatment of Leprosy
Rifampicin: Reddish urine
Clofazimine: Dark brown skin discoloration
Dapsone: Hemolytic anemia
Medical Management of lepra Reactions
High Risk: MB + nerve impairment
Clinical indications
Nerve pain
Loss of sensation
Loss of function
management of Mild Lepra reactions (Type 1 and 2)
Features: Mildly swollen skin lesion, Mild fever
Mild analgesics
Continue MDT
Do nerve function assessment every 2 weeks
Advise Bed rest
Management of Severe Lepra reactions
Prednisolone x 12 weeks
and.or clofazzimine x 3months + continue MDT
Nerve Fx assessment every 2 weeks
Alagesics
Refer persistent, non responding reactions
Severity grading for Lepra reaction
Mild - only the skin
Severe - skin, nerve and systemic
Characteristics of Lepra reactions
Type I - reversal reaction
Type II -erythema nodosum leprosum
Type 1 (Reversal Reaction)
Mostly borderline
Associated wih alteration in CMI due to sudden increase inCMI
Type 2 (ENL)
Mostly lepromatous
Immune-complex syndrome due to precipitation of antigen and antibody complexes in tissues spaces, blood, lymphatics
Peripheral nerve inflammation manifests into 2 ways in Leprosy
- Enlarged and/or very painful
2. Silent neuritis
Impairment, disability and deformity
Claw hand
Foot ulcer - posterior tibial nerve
Foot drop - Peroneal nerve damage
Ocular complications - Facial or trigeminal nerve damage
