Leprosy - Penn State York
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Transcript Leprosy - Penn State York
Nadine Chase & Priyanka Patel
Genus: Mycobacterium
Family: Mycobacteriaceae
Mycobacterium Leprae
Acid-fast Bacillus
Gram Positive
Bacillus shape
Single arrangement
Aerobic
Optimum growth
temperature is 30°
Trivia
Can not be grown in
culture
http://asylumeclectica.com/asylum/malady/archives/leprosy/leprosy4.jpg
Sehgal, Alfica. Leprosy, Deadly Diseases and Epidemics. Philadelphia, PA, 2006.
Sehgal, Alfica. Leprosy, Deadly Diseases and Epidemics. Philadelphia, PA, 2006.
Tuberculoid
Leprosy
Pauci-bacillary (PB) Leprosy
Well defined skin lesions that are
numb
1-5 skin lesions
Lepromatous Leprosy
Multi-bacillary (MB) Leprosy
Chronically stuffy nose
Many skin lesions and nodules
>5 skin lesions
Skin
tissue
Peripheral nerves
Mucus membranes
Bacteria prefers outer cooler parts of the
body
Sehgal, Alfica. Leprosy, Deadly Diseases and Epidemics. Philadelphia, PA, 2006.
Widespread
organism
living in water and food
sources
Obligate Parasites (cannot
live independently)
Fish
Insects
Not
very contagious
Air born disease
Droplets discharged from the
respiratory tract
Nasal secretions
Prolonged contact with excretions
from lesions
Slow replication time
Long incubation period
Affinity for macrophages
and Schwann cells
In Schwann cell
Mycobacterium binds to
the G domain of alpha
chain of laminin 2 in
the basal lamina
Stimulates cell
mediated immune
response which causes
swelling, chronic
inflammatory response
Ultimately leads to
axonal (nerve) death
http://www.med.nyu.edu/news_and_views/images/leprosy.jpg
Normal Nerve Cell
Nerve Cell enlargement
Arnold, Harry. Modern Concepts of Leprosy. Springfield, IL, 1953.
Avoid
contact
with infected
persons
99% of the
population
have natural
immunity
http://www.ruggedelegantliving.com/journal/images/2003/05/01/sars.mask.jpg
Long incubation
period
Skin lesions with
decreased sensitivity
Numbness
Muscle weakness
Cosmetic
Disfiguration
Death is usually
caused by a
secondary
opportunistic disease
http://www.wrongdiagnosis.com/l/leprosy/deaths.htm
Leprosy
Skin Test
Inactive Leprosycausing bacteria
injected into skin
Body will react to the
Leprosy antigens
Check injection 3
days and 28 days later
Positive skin reaction
is seen in Tuberculoid
Leprosy only
Normal result: little
to no skin irritation
around injection site
http://www.nlm.nih.gov/medlineplus/ency/article/003383.htm
Shave
Biopsy
Least invasive
Superficial layers
of lesion scraped
off
No stitches
required
Bacteria can be
identified on a
slide
http://www.nlm.nih.gov/medlineplus/ency/article/003383.htm
Punch
Biopsy
Small cylinder
of skin
removed
Sizes vary
depending on
size of lesion
May require
stitches
http://www.nlm.nih.gov/medlineplus/ency/article/003383.htm
Excisional
Biopsy
Local
anesthetic
applied
Entire lesion is
removed
Stitches are
usually needed
http://www.nlm.nih.gov/medlineplus/ency/article/003383.htm
Methacholine sweat testing
An intradermal injection of methacholine
demonstrates the absence of sweating in
leprous lesions.
Helpful to identify diagnosis when lesions are
not visible on dark skin individuals
Arnold, Harry. Modern Concepts of Leprosy. Springfield, IL, 1953.
Multi-drug
therapy
PB
Leprosy
Two Drugs:
Rifampicin and
Dapsone for 6
months
MB Leprosy
Three Drugs:
Rifampicin,
Dapsone,
Clofazimine for
12 months
http://www.nlm.nih.gov/medlineplus/ency/article/003383.htm
Sehgal, Alfica. Leprosy, Deadly Diseases and Epidemics. Philadelphia, PA, 2006.
Special
Footwear to prevent foot ulcers
Grunberg, E., Babger, LF, et al. Leprosy. New York, 1951.
Age
Children
are more susceptible
Bimodal age distribution with peaks
at ages 10-14 and 35-44 with higher
susceptibilities in younger years
Sex
Higher infection rate in males
compare to females
Ratio of infection is 2:1
Race
African
blacks are highly
susceptible to the tuberculoid form
of leprosy
Caucasians and Chinese are more
susceptible to the lepromatous
type of Leprosy
Its more rural than urban disease in
Asia and Pacific Basin
http://tmcr.usuhs.mil/tmcr/chapter34/large34/34-01.jpg
2002 Data
1,000 deaths in North and South America
96 cases in the U.S
3,000 deaths in South East Asia
1,000 death in Eastern Mediterranean
1,000 deaths Western Pacific
2005 Data
166 new cases were reported in U.S.
60% of these cases occurred in:
California
Louisiana
Massachusetts
New York
Texas
HANSEN DISEASE (LEPROSY)
Number of reported cases, by year
United States, 1973-2003
www.cdc.gov/epo/dphsi/annsum/2003/slides/hansgraf.ppt
Attempt
to identify new drugs that can
stop the neural damage caused by the
bacteria
Bacteria needs to recognize certain type
glycoprotein on the cell surface to bind
with and subsequently enter the cell
If these glycoprotein can be identified
and a drug can interfere with the binding
between the bacterium and the protein,
this could potentially prevent entry of the
bacteria and stop neural damage
Leprosy
has been found to NOT be
hereditary
If twin siblings become infected, the
disease is passed from one to the other
solely because of the proximity in which
they live
Twin A acquired the disease at age 15
Twin B at age 19
The disease effects the twins differently
Twin A
Twin B
Chakravartti, M.R. and Vogel, F. A Twin Study on Leprosy. Germany, 1973.
Arnold, Harry. Modern Concepts of Leprosy. Springfield, IL, 1953.
Chakravartti, M.R. and Vogel, F. A Twin Study on Leprosy. Germany, 1973.
Grunberg, E., Babger, LF, et al. Leprosy. New York, 1951.
http://www.cdc.gov/ncidod/dbmd/diseaseinfo/hansens_t.htm
http://www.nlm.nih.gov/medlineplus/ency/article/003383.htm
http://tmcr.usuhs.mil/tmcr/chapter34/large34/34-01.jpg
http://www.wrongdiagnosis.com/l/leprosy/deaths.htm
“Leprosy. “eMedicine from webmed.
http://www.sunysccc.edu/academic/mst/microbes/16mlepr.htm 21 July 2007.
“Leprosy, The Disease” World Health Organization; Regional Office for Southeast
Asia.www.searo.who.int/En/Section10/section20/section57_8963.htm. 22 December
Sehgal, Alfica. Leprosy, Deadly Diseases and Epidemics. Philadelphia, PA, 2006.
2006.