Leishmania

Question 1

What insect vector transmits the Leishmania parasite?

Answer 1

Sandfly

Question 2

Name the species of vector that is common to the eastern hemisphere

Answer 2

Phlebotomus

Question 3

Name the species of vector that is common to the western hemisphere

Answer 3

Lutzomyia

Question 4

Define and describe the promastigote stage of the Leishmania parasite

Answer 4

It is the flagellate, mobile stage, lives in the sandfly midgut

Question 5

Define and describe the amastigote stage of the Leishmania parasite

Answer 5

The replicative stage, lacks a flagellum, lives in mammalian macrophages

Question 6

What are the three main forms of pathology in humans?

Answer 6

Cutaneous, mucocutaneous and visceral

Question 7

What form of pathology is exhibited during infection of the L.major species of Leishmania?

Answer 7

Cutaneous

Question 8

What form of pathology is exhibited during infection of the L.brasiliensis species of Leishmania?

Answer 8

Mucocutaneous

Question 9

What form of pathology is exhibited during infection of the L.tropica species of Leishmania?

Answer 9

Cutaneous

Question 10

What form of pathology is exhibited during infection of the L.donovani species of Leishmania?

Answer 10

Visceral

Question 11

Define and describe cutaneous pathology

Answer 11

Skin lesions, usually painless ulcer like appearance, can be fairly deep, usually self heals within 6 weeks. Not usually treated in third world countries as not fatal, although scar can be unsightly. Satellite lesions.

Question 12

Define and describe mucocutaneous pathology

Answer 12

Cutaneous disseminated - macrophages metastasized. Mucous membranes, destroys them. Disabling and disfiguring. Requires treatment.

Question 13

Define and describe visceral pathology

Answer 13

Parasites present in the viscera - soft internal organs of the abdominal cavity/ thorax; in bone marrow. Splenomagy, fevers, wasting away. Lethal. Requires treatment. Kala-azar, black fever. DEATH FROM 2* INFECTIONS. Severe HIV.
Chronic inflammation of the spleen. Remodeling of the marginal zone, mediated by TNF.

Question 14

Describe DCL

Answer 14

Diffuse Cutaneous Leishmaniasis - scaly lesions

Question 15

Why is there an inflammatory response in the liver?

Answer 15

Early AM growth - controlled by day 28. Liver infection coincides with spleen infection.

Question 16

Hepatic infection?

Answer 16

Self limiting, more NO = necrosis

Question 17

How is leishmaniasis diagnosed (5 ways)?

Answer 17

AM in tissue sample (splenic aspirate, liver biopsy, fluid from CL), ag detection, PCR, serology, Leish skin test

Question 18

Vaccine targets?

Answer 18

Sandfly saliva - vaccine induced immunity - vigorous delayed type hypersensitivity response, parasite survivial reduced