Leishmaniasis

Question 1

Where are the most endemic areas for visceral leishmaniasis?

Answer 1

Sudan
Bangladesh, India, Nepal
Brazil

90% of cases in these countries!

Question 2

What is the investigation of choice for V.Leish?

Answer 2

Bone marrow or spleen aspirate and microscopy

Amastigotes inside macrophages

Question 3

Rx of choice for VL?

Answer 3

Liposomal ampho

Also: Anitmonials - don’t work so well
Ampho B

Question 4

What are the 2 stages of the life cycle that may be seen in cutaneous leishmaniasis?

Answer 4

Amastigote
Promastigote (only from vector)

Question 5

Describe how to identify an emastigote?

Answer 5

Small - 2-4 microns
Intracellular pathoge
Prominent nucleus, with a bar-shaped kinetoplast

Question 6

Vector for leish in old world?

Answer 6

Phlebotomos fly

Question 7

Vector for leish in new world?

Answer 7

Lutzomyia fly

Question 8

What is this?

Answer 8

Amastigotes
Mucocutaneous leish

Question 9

Infective stage of cutaneous leish?

Answer 9

Promastigote

Question 10

What causes cutaneous leish in old world?

Answer 10

L.major
L.Tropica
L.Ethiopica

Question 11

Most common cause of visceral leish in old world?

Answer 11

L. infantum/chagasi (Europe) and L. donnovani (middle east, Horn of Africa)

Question 12

Cause of cutaneous leish in new world?

Answer 12

L. braziliensis (jungle)
L.peruviana (highlands), L.panama, L.mexicana, L.Guyanensis

L.braziliensis causes mucocutaneous disease

Question 13

What is the classical presentation of leish?

Answer 13

Slowly enlarging nodule at bite site, most self heal, crust forms centrally leading to uler with raised margins, leave hypopigmented and depressed scar

Question 14

What is the definition of disseminated leish?

Answer 14

> 10 lesions in more than 1 limb/extremity

Question 15

What is diffuse cutaneous leish?

Answer 15

Begins as localised disease, and does not ulcerate.
Soft nodules or plaques on face / limbs / entire body.
Patients usually have a defect in cell mediated immune response

Question 16

What species often cause Diffuse CL?

Answer 16

Amazonensis, mexicana, aethiopica

Question 17

Which species causes mucosal involvement of leish?

Answer 17

Caused by Viannia subegenus - mainly by L.V. braziliensis (also guyanensis, panamensin, peruviana)

Question 18

Diagnosis of cutaenous leish?

Answer 18

Direct smear from skin scrape, giemsa stain

In specialist labs: can culture promastigotes
Leishmanin skin test - like TST for TB
ELISA
PCR

Question 19

How do you Rx cutaenous leish?

Answer 19

IV pentavalent antimonials (Sb5+, stibogluconate) for 20 days

Question 20

How do you treat mucosal leish?

Answer 20

stibogluconate Sb5+ (pentavalent antimonials) IM or IV for 30 days

Question 21

What to do if patient has laryngeal involvement of mucosal leish?

Answer 21

Amphoterecin B

Question 22

What would you do at 20 days following Rx for cutaenous leish?

Answer 22

Failure of treatment at 20 days is if the lesion is extending despite 20 days of therapy

Look for 50% improvement over 20 days

Question 23

Alternative Rxs for visceral leish?

Answer 23

Anitmonials if Liposomal amphoterecin not available

Question 24

New World visceral leishmaniasis species?

Answer 24

Leishmania infantum/Chagasi

Question 25

How will you differentiate diffuse and disseminated leish?

Answer 25

Diffuse - Skin test -ve - Lots of organisms on biopsy/scrape - Skin lesions do not ulcerate - No antibodies/immune response - No mucosal disease

Question 26

Parasitic stages of leish - infective and diagnostic?

Answer 26

Promastigotes from saliva of fly - infective Amastigotes - tissue. Diagnostic Very rare to see promastigotes in leish. Only in culture.

Question 27

Diagnosis of leish?

Answer 27

Amastigotes - 2-4 microns, kinetoplast - bar shaped DNA

Question 28

What is difference between leish and histo?

Answer 28

Histo no nucleus, yeast inside macrophage

Question 29

Which strain of VL has a reservoir other than humans?

Answer 29

Infantum Dogs

Question 30

What is the reservoir for L.Donnavani?

Answer 30

Humans

Question 31

Classical presentation of VL?

Answer 31

Fever - prolonged Splenomegaly Hepatomegaly Lymphadenopathy Bone marrow invasion - pallor Hyperpigmentation - Kala Azar often wasted and malnourished

Question 32

Bloods in VL?

Answer 32

Pancytopenia Hypergammaglobulinaemia

Question 33

Post treatment manifestation of VL

Answer 33

PKDL - chronic form Often on face Dermatitis - pale spots and painless nodules - contain amastigotes! Up to 50% of people in East Africa

Question 34

Diagnosis of VL?

Answer 34

Parasite detection Antibody detection Antigen detection (urine antigen test)

Question 35

parasite detection, best method?

Answer 35

Splenic aspiration Bone marrow Bx Lymph node Bx (very poor)

Question 36

The now best way of diagnosing VL apart from parasite detection?

Answer 36

Direct agglutination testing Rapid tests Always do before splenic aspiration

Question 37

Cause of false negatives and false positives in serology for VL?

Answer 37

HIV - false neg Asymptomatic immunity - false positive

Question 38

Problem of rK39 antibody RDT?

Answer 38

Varies depending on the region - Asia excellent sensitivity, Ethiopia bad!

Question 39

Options for Rx VL

Answer 39

GS: Ampho (liposomal) + Miltefisine Pentavalent antimonial Paramomycin

Question 40

How to change Rx if have HIV and VL??

Answer 40

Longer course Rx

Question 41

Options for Rx for PKDL?

Answer 41

Same Rx but longer