LEPROSY Flashcards
__ a chronic granulomatous disease affecting mainly the skin and nerves caused by the obligate intracellular pathogen __
LEPROSY
Mycobacterium leprae
Leprosy primarily involves the ____
skin and nerves
Leprosy diagnosis:
Based on clinical signs and symptoms, hallmarks
include:
1.
2.
3.
loss of sensation within skin lesions,
nerve swelling or pain, or
demonstration of acid-fast bacilli in skin smears or biopsies
More than 80% of all new cases are detected in only 3 countries __
India, Brazil, and Indonesia
I B I
a chronic granulomatous infection caused by
Mycobacterium leprae.
Leprosy
It infects mucous cutaneous tissues and peripheral
nerves, leading to loss of sensation on the skin—with or
without dermatologic lesions—and the development of
incapacities during the progression of the disease
Lerosy
one of the oldest diseases known to afflict
mankind.
Leprosy
A Norwegian physician, first to describe M. leprae
GERHARD ARMAUER HANSEN
Leprosy is a.k.a
Hansen disease.
Single nucleotide polymorphisms (SNPs) 4 types and 16 subtypes:
o SNP Type 1: in Southeast Asia
▪ 4 Subtypes: A to D
o SNP Type 2: in East Africa
▪ 4 Subtypes: E to H
o SNP Type 3: in European/North African region
▪ 5 Subtypes: I to M
o SNP Type 4: in West Africa
▪ 3 Subtypes: N to P
For decades, treatment of leprosy was done continuously with __
dapsone alone (monotherapy)
Causative agent of lepros
MYCOBACTERIUM LEPRAE
incubation period of
3-7 years
host genes:
o Toll-like receptors (TLR)
o Nucleotide-binding oligomerization domain
containing 2 (NOD2)
o Mannose receptor C-type 1 lectin (MRC1) →
modulate autophagy.
GENETIC RISK FACTORS
Human leukocyte antigen (HLA) complex genes (class I & II))
Shared genetic background between leprosy and a number
of inflammatory diseases including:
o Crohn disease (NOD2)
o MI (lymphotoxin α)
o Type 1 diabetes and psoriasis (vit D receptor)
o Parkinson disease (E3 ubiquitin-protein ligase
[PARK2])
may last for months or years before moving to spontaneous
cure or toward one of the poles or borderline forms of the clinical spectrum
INDETERMINATE LEPROSY
• better cell-mediated immunity.
• With well-defined plaques
POLAR TUBERCULOID LEPROSY
A special self-healing type of tuberculoid leprosy.
INFANTILE NODULAR LEPROSY
POLAR LEPROMATOUS LEPROSY
gives the appearance of a lion’s face, known
as leonine facies
complete lack of cell-mediated immunity.
POLAR LEPROMATOUS LEPROSY
main skin manifestation is infiltration
LUCIO LEPROSY
3 BORDERLINE FORMS
- Borderline-tuberculoid
- Borderline-borderline
- Borderline-lepromatous
presents a clear infiltrative band around the periphery of the lesions
BORDERLINE-TUBERCULOID
has classical foveolar lesions
BORDERLINE-BORDERLINE
Foveolar and nodular infiltrated lesions
BORDERLINE-LEPROMATOUS
dryness of the skin and
alopecia restricted to the territory of the lesions.
Tuberculoid leprosy
frequent symptom associated with leprosy
cases
Paresthesia
Triple Lewis response
o Within 5 to 10 seconds → erythema will result from the
direct action of histamine on the capillaries, causing
vasodilation in both areas, normal and lesional.
o After 2 minutes → a secondary erythema caused by
capillary dilation will occur only on normal skin.
o Last phase → exudation of liquid to the dermis,
resulting in wheal formation in both areas.
IODINE-STARCH OR ALIZARIN RED:
Findings:
o Normal skin →
o Leprosy lesions →
Findings:
o Normal skin → bluish or dark brown (iodine-starch) or violet (alizarin red)
o Leprosy lesions → no reaction (anhidrosis) or irregular sweating (hypohidrosis).
Loss of sensation via Semmes-Weinstein monofilaments
indicators:
__ → indicates diminished sensation of light touch
(0.16-0.4 g),
___ → indicates diminished protective sensation
(0.6-2 g), and
____ → indicates more profound loss of protective
sensation (4-300 g).
Loss of sensation via Semmes-Weinstein monofilaments
indicators:
o Blue → indicates diminished sensation of light touch
(0.16-0.4 g),
o Purple → indicates diminished protective sensation
(0.6-2 g), and
o Red → indicates more profound loss of protective
sensation (4-300 g).
divides the disease into 5 forms based on the number of acid-
fast bacilli and the degree of lymphocytic infiltration and organization
RIDLEY-JOPLING CLASSIFICATION SYSTEM
