Parasitology Lecture 10

Question 1

what insects transmits leishmaniasis?

Answer 1

sand flies

Question 2

t or f: leishmania is an obligate intracellular pathogen

Answer 2

true

Question 3

___ out of 30 species of leishmania can infects mammals

Answer 3

21

Question 4

all species of leishmania are morphologically ________

Answer 4

indistinguishable

Question 5

where is leishmania typically found?

Answer 5

in the tropics and subtropics

Question 6

how many cases of leishmania are found worldwide?

Answer 6

12 million

Question 7

t or f: most deaths from leishmania occur in kids

Answer 7

true (70% are kids)

Question 8

what sand fly species is found in Africa & Asia?

Answer 8

phlebotomas

Question 9

what sand fly species is found in Central & South America?

Answer 9

lutzomyia

Question 10

when a sandfly takes a bloodmeal, it injects _______ into the skin, then these promastigotes are phagocytized by _________ and here they lose their ______ and become ________. this multiplication of ______ eventually ruptures the _______. then, a sandfly can come by and take a blood meal where it can ingest ______ that are infected with _______.

Answer 10

promastigotes, macrophages, flagella, amastigotes, amastigotes, macrophage

macrophages, amastigotes

Question 11

in the midgut of the sandfly, the amastigote converts back into the _________ stage, where it divides and migrates to the ______

Answer 11

promastigote

proboscis

Question 12

in leishmania, each parasite has a _____ and _______

Answer 12

nucleus + kinetoplast

Question 13

t or f: in leishmania, both the nucleus and kinetoplast contain DNA, but the kinetoplast is larger

Answer 13

false - kinetoplast is smaller

Question 14

the development of leishmania is thought to be an immune balancing act between the ___ and ___ responses

Answer 14

th1 and th2

Question 15

which response favors worsening disease and increases parasite burden?

Answer 15

th2 (the humoral response)

Question 16

which response favors tuberculoid/granulomatous disease and reduces parasite burden?

Answer 16

th1 (cellular immunity response)

Question 17

what form of leishmania is known as the “balkh sore” or “oriental sore”

Answer 17

cutaneous leishmania

Question 18

what form of leishmania is known as “espundia”

Answer 18

mucocutaneous leishmania

Question 19

what form of leishmania is known as “kala-azar”

Answer 19

visceral leishmania

Question 20

cell mediated immunity for cutaneous leishmania (CL) is usually ____, but ____ for visceral leishmania (VL)

Answer 20

strong, weak

Question 21

while CL is ____, VL is quite ____

Answer 21

common

Question 22

the natural course of most leishmania infections are formation of ____ then _______

Answer 22

boils, resolution

Question 23

common agent behind CL?

Answer 23

L. tropica and L. mexicana

Question 24

t or f: 90% of CL cases are in Afghanistan, Iran, Peru, Saudi Arabia, Syria, Brazil, Peru

Answer 24

true

Question 25

at the height of infection, CL lesions have a "_____" appearance, where the edges are raised and there is a central ______

Answer 25

volcano, crater

Question 26

if satellite lesions are found around the original ulcer, what could this be a sign of?

Answer 26

could be a sign that immunity is walling off and there is a risk of onward spread

Question 27

true or false: a few cases of leishmaniasis have been detected in Texas and Oklahoma

Answer 27

true

Question 28

define the term "autochthonous"

Answer 28

native to the place where its found

Question 29

what is the agent behind MCL?

Answer 29

mostly L. braziliensis

Question 30

90% of MCL cases are in Bolivia, ____, and _____

Answer 30

Peru, Brazil

Question 31

MCL begins in the ____ cavity

Answer 31

nasal

Question 32

what is the agent behind VL?

Answer 32

L. donovani

Question 33

90% of VL cases occur where?

Answer 33

Bangladesh, India, Sudan, Ethiopia, Brazil

Question 34

what is the mortality rate of VL if it is untreated?

Answer 34

95-100%!!!

Question 35

what 2 organs are commonly enlarged due to VL?

Answer 35

spleen and liver (spleen is usually bigger)

Question 36

define "hepatosplenomelagy"

Answer 36

enlargement of the spleen and liver

Question 37

true or false: immunocompromised people are more likely to get severe leishmania

Answer 37

true

Question 38

true or false: leishmania infection increase HIV acquisition risk 100-1000x

Answer 38

true

Question 39

true or false: VL accelerates progression of HIV

Answer 39

true

Question 40

true or false: HIV positive individuals who have VL are commonly seropositive

Answer 40

false - they are seronegative

Question 41

what is diffuse cutaneous leishmaniasis (DCL)?

Answer 41

uncontrolled skin lesions all over the body

Question 42

diffuse cutaneous leishmaniasis is clinically indistinguishable from ________

Answer 42

leprosy

Question 43

t or f: DCL is due to the inability of the patient's immune system to mount a complete immune response against its target

Answer 43

true

Question 44

in order to diagnose leishmania, the lab should isolate the parasite with help from ______ labs. prior to collecting the specimen, they should be contacted.

Answer 44

reference

Question 45

if the culture is positive, the species can be identified using ________ assays or using _______ analysis

Answer 45

DNA-based, isoenzyme

Question 46

most sensitive leishmania tests?

Answer 46

molecular

Question 47

for diagnosis of VL, _____ should be used

Answer 47

serology

Question 48

for MCL diagnosis, biopsies can be used then a _____ or _____ test may be done

Answer 48

culture / molecular

Question 49

for CL diagnosis, biopsies can be used then a _____ or _____ test may be done. also, skin scrapings can be taken from the lesion and a ______ stain can be done (3x)

Answer 49

culture / molecular, Giemsa

Question 50

diagnosis can also be done by looking at intracellular ______

Answer 50

amastigotes

Question 51

amastigotes are about ______ in diameter

Answer 51

1-5 microns

Question 52

amastigotes lack ______

Answer 52

flagella

Question 53

amastigotes divide by _____ ______ at 37 C

Answer 53

binary fission

Question 54

leishmania amastigotes typically have a large ____, a prominent ______, but a short ______

Answer 54

nucleus, kinetoplast, axoneme

Question 55

t or f: amastigotes are typically phagocytized and not found in blood

Answer 55

t

Question 56

diagnosis can also be done looking at ________

Answer 56

promastigotes

Question 57

promastigotes are typically _______ and found in blood as well as in the _____ of sandflies

Answer 57

flagellated, midgut

Question 58

promastigotes have an elongated shape and are about ____ microns long

Answer 58

10-12

Question 59

nucleus is found in the ____, the kinetoplast of promastigotes is typically found on the ______ end and this is also where the _____ is

Answer 59

center, anterior, flagellum

Question 60

promastigotes can be found by taking a culture from the blood of a person and placing in ____ medium, where the amastigotes think they're in a sandfly and transform into a promastigote

Answer 60

NNN

Question 61

promastigotes bind to ______

Answer 61

macrophages

Question 62

growing in a vacuole inside the macrophage allows leishmania to avoid _____ substances that the macrophages releases

Answer 62

lytic

Question 63

all cases of ___ and __ should be treated but not all cases of ___ require treatment

Answer 63

MCL, VL, CL

Question 64

treatments for leishmania?

Answer 64

- oral miltefosine - liposomal amp B - pentavalent antimonial compounds

Question 65

prevention of leishmania?

Answer 65

- avoid nighttime activities because sandflies often bite then - high grasses are more protective (sandflies fly low) - deal with animal reservoir