Species of protozoan parasite
Leishmania tropica
is a
flagellate
parasite
and the cause of
anthroponotic
[
dubious
–
discuss
]
cutaneous leishmaniasis
in
humans
.
[2]
This parasite is restricted to
Afro-Eurasia
and is a common cause of infection in
Afghanistan
,
Iran
,
Syria
,
Yemen
,
Algeria
,
Morocco
, and northern
India
.
[3]
History
[
edit
]
The first description of
Leishmania tropica
was done in 1903 by
James Homer Wright
, an American
pathologist
. In 1914, it was suggested that
L. tropica
should be divided into two
subspecies
, namely
L. tropica minor
and
L. tropica major
, based on the size of the parasites found in skin
lesions
.
[3]
Later, these two subspecies turned out to be
epidemiologically
different and were correlated to different types of lesions.
L. tropica minor
causes dry
nodular
lesions in urban environments, while
L. tropica major
causes wet
ulcerating
lesions in rural regions.
[4]
Bray et al. therefore proposed in 1973 that the subspecies should be considered as two separate species,
L. tropica major
became
L. major
, and
L. tropica minor
became
L. tropica
,
[4]
which is the naming that is still being used.
[3]
Biology
[
edit
]
The parasite has an interesting biology since it is very
heterogeneous
biochemically,
serologically
, and genetically compared to other
Leishmania
species.
[5]
The different
strains
have been shown to cause different patterns of
pathogenicity
and
humoral immune responses
in
BALB/c mice models
.
[3]
Fusion and hybridization of different
L. tropica
strains can be efficiently induced
in vitro
by exposure of
promastigotes
(a stage of the life cycle) to
DNA damage
stress.
[6]
Life cycle
[
edit
]
Leishmania
species alternate between two main life forms: intracellular
amastigotes
in the
sandfly
? the
vector
? and extracellular motile
promastigotes
in the
mammal
? the
host
.
[8]
In the mammalian host, promastigotes are introduced into the skin by the bite of a sandfly. After being taken up by
phagocytes
, they transform into intracellular amastigotes and stay in this form during the remaining life cycle in the mammalian host.
[8]
Through simple
division
, they can multiply and proceed to infect other phagocytotic cells. Later, depending partly on the
immunity
of the host, the infection can become symptomatic and result in leishmaniasis.
[7]
Sand flies become infected by ingesting phagocytes with
Leishmania
from a mammalian host. Then, in the sandfly stage, the process differs between
Leishmania
species. In the life cycle of
L. tropica
, it develops back into the promastigote stage inside the
midgut
of the sandfly vector and migrates to the
proboscis
of the sandfly, whereafter the life cycle can repeat itself.
[7]
Hosts and vectors
[
edit
]
Humans are the main reservoir hosts of
L. tropica
.
[9]
Rock hyraxes
(
Procavia capensis
)
[9]
are a possible reservoir in
Israel
.
[10]
Natural infection by
L. tropica
has also been demonstrated in
domestic dogs
,
[10]
red foxes
,
golden jackals
,
gundis
, and other species of wild
rodents
.
[3]
The main sandfly
[10]
vector for
L. tropica
is
Phlebotomus
sergenti
. Other reported vector species are
P. arabicus
,
P. guggisbergi
,
P. chabaudi
,
P. rossi
, and
P. saevus
.
[3]
Clinical manifestations
[
edit
]
L. tropica
causes a broad spectrum of leishmaniasis forms in humans. Most common is a variant called dry-type
cutaneous leishmaniasis
. After an
incubation period
lasting more than 2 months, a small brownish
nodular
lesion will appear with a slowly extending plaque reaching a size of 1?2 centimetres (0.39?0.79 in) after 6 months. This will heal after about 1 year but leaves a scar.
[11]
Other forms of the disease, which occur more rarely in humans, include
visceral leishmaniasis
,
post-kala-azar dermal leishmaniasis
(a variant of visceral leishmaniasis),
viscerotropic leishmaniasis
, and
leishmaniasis recidivans
(a variant of cutaneous leishmaniasis).
[3]
Dogs are known to rarely suffer from
visceral
,
skin
, and
mucosal
infection with this species.
[10]
In cats
asymptomatic
infection is thought to be common.
[10]
Skin and/or mucosal infection is the most common form, with or without visceral infection.
[10]
Feline visceral infection may occur alone.
[10]
Leishmaniasis recidivans
[
edit
]
This rare variant of cutaneous leishmaniasis is caused solely by
L. tropica
in the
Old World
and by
L. braziliensis
in the
New World
. It causes a slowly progressing
lesion
, usually on the face, and is characterized by the development of
papules
or
nodules
which form mostly around or in the site of primary healed lesions. Lesions of
leishmaniasis recidivans
stay many years and rarely respond to treatment, thus causing
disfigurement
and becoming destructive with the years.
[12]
References
[
edit
]
- ^
Aoun, K.; Bouratbine, A. (2014).
"Cutaneous Leishmaniasis in North Africa: a review"
.
Parasite
.
21
.
EDP Sciences
: 14.
doi
:
10.1051/parasite/2014014
.
PMC
3952656
.
PMID
24626301
.
- ^
Karimi, Taiebeh; Sharifi, Iraj; Aflatoonian, Mohammad Reza; Aflatoonian, Behnaz; Mohammadi, Mohammad Ali; Salarkia, Ehsan; Babaei, Zahra; Zarinkar, Farzaneh; Sharifi, Fatemeh; Hatami, Nima; Khosravi, Ahmad; Eskandari, Arsalan; Solimani, Elyas; Shafiee, Mehdi; Mozaffari, Masoumeh (2021).
"A long-lasting emerging epidemic of anthroponotic cutaneous leishmaniasis in southeastern Iran: population movement and peri-urban settlements as a major risk factor"
.
Parasites & Vectors
.
14
(1): 122.
doi
:
10.1186/s13071-021-04619-3
.
ISSN
1756-3305
.
PMC
7903377
.
PMID
33627184
.
S2CID
232036410
.
- ^
a
b
c
d
e
f
g
Rostamian, Mosayeb; Niknam, Hamid M. (2019).
"
Leishmania tropica
: What we know from its experimental models"
.
Advances in Parasitology
.
104
: 6?7 – via
Elsevier Science Direct
.
- ^
a
b
Bray, R.S.; Ashford, R.W.; Bray, M.A. (1973).
"The parasite causing cutaneous leishmaniasis in Ethiopia"
.
Transactions of the Royal Society of Tropical Medicine and Hygiene
.
67
(3): 345?348.
doi
:
10.1016/0035-9203(73)90111-9
.
PMID
4778189
– via Elsevier Science Direct.
- ^
Magill, Alan J (2013-01-01).
"99 - Leishmaniasis"
. In Magill, Alan J.; Hill, David R; Solomon, Tom; Ryan, Edward T (eds.).
Hunter's Tropical Medicine and Emerging Infectious Disease
(Ninth ed.).
London
: W.B. Saunders. pp. 739?760.
doi
:
10.1016/b978-1-4160-4390-4.00099-0
.
ISBN
978-1-4160-4390-4
. Retrieved
2022-12-15
.
- ^
Louradour, I; Ferreira, TR; Duge, E; Karunaweera, N; Paun, A; Sacks, D (2022-01-07).
"Stress conditions promote
Leishmania
hybridization in vitro marked by expression of the ancestral gamete fusogen HAP2 as revealed by single-cell RNA-seq"
.
eLife
.
11
.
doi
:
10.7554/eLife.73488
.
PMC
8794473
.
PMID
34994687
.
S2CID
245835348
. e73488.
- ^
a
b
c
CDC -
Centers for Disease Control and Prevention
(2020-02-18).
"CDC - Leishmaniasis - Biology"
. CDC
. Retrieved
2022-12-15
.
- ^
a
b
Gossage, Sharon M; Rogers, Matthew E; Bates, Paul A (2003).
"Two separate growth phases during the development of Leishmania in sand flies: implications for understanding the life cycle"
.
International Journal for Parasitology
.
33
(10): 1027?1034.
doi
:
10.1016/S0020-7519(03)00142-5
.
PMC
2839921
.
PMID
13129524
.
- ^
a
b
Ashford, Richard W. (1996).
"Leishmaniasis reservoirs and their significance in control"
.
Clinics in Dermatology
.
14
(5): 523?532.
doi
:
10.1016/0738-081X(96)00041-7
.
PMID
8889331
.
- ^
a
b
c
d
e
f
g
Iowa State University
;
Institute for Cooperation in Animal Biologics
;
Iowa State University College of Veterinary Medicine
;
World Organisation for Animal Health
/OIE Collaborating Centre for Diagnosis of Animal Disease and Vaccine Evaluation in the Americas; OIE Collaborating Centre for Day-One Veterinary Competencies and Continuing Education;
United States Department of Agriculture
(2017).
"Leishmaniasis"
(PDF)
.
- ^
Meymandi, Simin; Dabiri, Shahriar; Dabiri, Darya; Crawford, Richard I.; Kharazmi, Arsalan (2004).
"A quantitative study of epidermal Langerhans cells in cutaneous leishmaniasis caused by
Leishmania tropica
"
.
International Journal of Dermatology
.
43
(11): 819?823.
doi
:
10.1111/j.1365-4632.2004.02359.x
.
ISSN
0011-9059
.
PMID
15533064
.
S2CID
22132211
.
- ^
Sharifi, Iraj; Fekri, Ali Reza; Aflatoonian, Mohammad Reza; Khamesipour, Ali; Mahboudi, Fereidoun; Dowlati, Yahya; Nadim, Abolhassan; Modabber, Farrokh (2010).
"Leishmaniasis recidivans among school children in Bam, South-east Iran, 1994-2006"
.
International Journal of Dermatology
.
49
(5): 557?561.
doi
:
10.1111/j.1365-4632.2010.04419.x
.
ISSN
1365-4632
.
PMID
20534092
.
S2CID
8747858
.
Further reading
[
edit
]
- Saroufim, Maya; Charafeddine, Khalil; Issa, Grace (October 2014).
"Ongoing Epidemic of Cutaneous Leishmaniasis among Syrian Refugees, Lebanon"
.
Emerging Infectious Diseases
.
20
(10): 1712?1715.
doi
:
10.3201/eid2010.140288
.
PMC
4193275
.
PMID
25279543
.
- Solomon, Michal; Schwartz, Eli; Pavlotsky, Felix (Aug 2014). "
Leishmania tropica
in children: A retrospective study".
Journal of the American Academy of Dermatology
.
71
(2): 271?7.
doi
:
10.1016/j.jaad.2013.12.047
.
PMID
24775403
.
- Krayter, Lena; Alam, Mohammad Zahangir; Rhajaoui, Mohamed; Schnur, Lionel F. (December 2014).
"Multilocus Microsatellite Typing reveals intra-focal genetic diversity among strains of
Leishmania tropica
in Chichaoua Province, Morocco"
.
Infection, Genetics and Evolution
.
28
: 233?239.
doi
:
10.1016/j.meegid.2014.09.037
.
PMID
25308380
.
- Hammoudeh, Nour; Kweider, Mahmoud; Abbady, Abdul-Qader; Soukkarieh, Chadi (Oct 2014).
"Sequencing and Gene Expression Analysis of
Leishmania tropica
LACK Gene"
(PDF)
.
Iranian Journal of Parasitology
.
9
(4): 574?583.
PMC
4345098
.
PMID
25759740
. Retrieved
9 February
2015
.
- Mahmoudzadeh-Niknam H, Kiaei SS, Iravani D (2007).
"
Leishmania tropica
infection, in comparison to
Leishmania major
, induces lower delayed type hypersensitivity in BALB/c mice"
.
Korean Journal Parasitology
.
45
(2): 103?9.
doi
:
10.3347/kjp.2007.45.2.103
.
PMC
2526302
.
PMID
17570972
.
External links
[
edit
]