Leishmaniasis Piscopo & Azzopardi 2006

Question 1

Piscopo & Azzopardi 2006 said that 4 points merit discussion regarding Leishmaniasa

Answer 1

1. resistance to conventional drug treatment has developed in certain areas of the world, neccessitating a change of firts line agents
2. rapid less invasive diagnostic procedures have been developed which are most useful in poorly resourced parts of the world
3. despite advances in the understanding of the immunology of the disease and the unravelling of the *Leishmania *genome a vaccine is still not available
4. Extent of disease in different individuals stresses the complex immunology of Leishmaniasis brought to the fore more recently with the adherent of HIV - leishmania

Question 2

90% of Leishmaniasis are borne by which countries?

1. Cutaneous Leishmaniasis
2. Visceral Leishmaniasis

Answer 2

1. Afghanistan, Pakistan, Syria, Saudi Arabia, Algeria, Iran, Brazil, Peru
2. Bangladesh, India, Nepal, Sudan, Brazil

Question 3

Desjeux 2001 suggested that global warming might have contributed to which observation?

Answer 3

Number of reported cases and geographical areas of leishmaniasis have increased.

Question 4

Leishmania is what sort of organism?

Answer 4

protozoan

Question 5

There are how many species of Leishmania?

And what is it about these species?

Answer 5

20

Each of which may cause a disease specific to the species and host response

Question 6

Prevalence of Leishmaniasis differs by ___ ___

Answer 6

geographical area

Question 7

Reservoirs of leishmaniasis are animals like ___ and ___ (____ cycle) and in countries such as Sudan ___ (____ cycle)

Answer 7

rodents and canines

zoonotic

humans

antrhoponotic

Question 8

what is the vector of Leishmania?

Answer 8

Sand fly

Question 9

The vector, the sand fly, ingests Leishmania protozoan in which form?

Answer 9

amastiogte

Question 10

In the digestive tract of the sand fly the amastigote develops into a ______

Answer 10

promastigote

Question 11

What form of Leishmania is injected into the susceptible host by the sand fly?

Answer 11

promastigote

Question 12

Sand flies transmit Leishmania how?

Answer 12

in their vomit! regurgitate it

Question 13

The promastigote develops into the amastigote form where in the human?

Answer 13

macrophages

Question 14

How many different species of sand fly can transmit Leish?

Answer 14

70

Question 15

What are the 2 main species of sand fly that can transmit the disease? and where are they associated with?

Answer 15

• Lutzomyia *- Americas
• Phlebotomous - *elsewhere

Question 16

When does the sandfly characteristically bite?

Answer 16

at dusk

Question 17

Infection is more commen in which gender? But why is this thought to be?

Answer 17

Men

may reflect an increased exposure to sand flies

Question 18

Although the disease occurs irrespective of age, in the Mediterranean which age is thought to be particularly susceptible? How many cases do these account for?

who found this out?

Answer 18

children 1-4yrs

more than half of cases in these countries

Grech et al 2000

Question 19

Untreated visceral leishmaniasis carries a mortality of ___%

Answer 19

70-95

Question 20

Cutaneous leish can disseminate to involve the mucosa resulting in _______

Answer 20

death from secondary infection

Question 21

what are the 3 main disease pathologies?

Answer 21

visceral

cutaneous

mucocutaneous

Question 22

The pathology of leish expressed depends on what 2 things?

Answer 22

leishmania sp.

zymodeme (electrophoretic isoenzyme pattern)

Question 23

The immune response to leish is ___ mediated

Answer 23

cell

Question 24

leishmania is an intracelluar or extracellular organims?

Answer 24

intracellular

mainly replicating as amastigotes inside macrophages

Question 25

the outcome of infection by leish will depend on what?

who discovered this?

Answer 25

whether the host mounts primarily a t-helper (TH1) or TH2 response

Heinzel et al 1989

Question 26

Roberts et al 2000 discovered that host genetics inevitably influence the type of immune response, explain further?

Answer 26

Studies in humans and mice have shown that genes such as those coding for natural resistance associated macrophages protein 1, TNF, or the MHC are thought ot play a major role in the outcome of infection

Question 27

Some cases are believed to harbour leish organisms for indefinite periods before the disease is expressed suggesting what sort of infection?

Answer 27

latent

costa et al 2002

Question 28

parasites have also been detected in ____ after a clinical cure

Answer 28

lymph nodes

Question 29

Epidemiolody true or false questions:

• *Leishmania *is endemic in Australasia?
• *Leishmania *can be transmitted through infected syringes?
• The epidemiology of L is tightly knit with the epidemiology of the sandfly
• the sandfly usually bites during the day
• The number of countries where L is endemic is set to increase with global warming?

Answer 29

1. False - L is not endemic to Australasia
2. True
3. True
4. False - sand fly does not bite during the day usually at dusk
5. True

Question 30

Visceral leishmaniasis true or false

1. Is characterised by splenomegaly and pancytopenia
2. carries a low mortality if not treated
3. the organisms is characteristically extracellular
4. fatalities are usually the result of secondary bacterial infections
5. almost always responds to antimony products

Answer 30

1. true
2. false - visceral leish does not carry a low mortality if not treated, you are likely to die
3. false - the organism is not extracellular it is intracellular neutrophils and macrophages
4. true
5. false - it does not always respond to antimony products

Question 31

Immunology true or false

1. an effective vaccine is available
2. the body response to infection is t-cell mediated
3. the disease manifestation depends oon L species and host response
4. immunosuppression predisposes to l infection
5. L organisms can remain dormant for years in the reticulo-endothelial system

Answer 31

1. false - there is no efffective vaccine
2. true
3. true
4. true
5. true

Question 32

Treatment true or false

1. Liposomal amphotericin is effective but very expensive
2. there are no oral medications to effectively treat L
3. oral miltofisine is very effective in the treatment of kala azar
4. cutaneous leish can be treated both by physical and pharmaological means
5. leish in the immunosuprresed usually necessitates secondary prophylaxis

Answer 32

1. True
2. false - there are in fact oral medications to treat leish
3. true
4. true
5. true

Question 33

Diagnosis true or false

1. Identification of amastigotes in tissue smears or histology are commonly used methods of diagnosis
2. antibody towards K39 antigen is proving useful, especially in field diagnosis of visceral leish
3. tissue cultures are used routinely
4. splenic aspirates are very sensitive and usually safe
5. leish PCR is useless on blood samples

Answer 33

1. true
2. true
3. false - tissue cultures are not routinely used
4. false - splenic aspirates are not safe
5. false - PCR can be used on blood samples