Lecture 20 - Leishmaniasis

Question 1

The clinical syndromes and manifestations of leishmaniasis vary widely but are often divided into the three clinically distinct syndromes of:

Answer 1

visceral leishmaniasis (VL)
cutaneous leishmaniasis (CL)
mucosal leishmaniasis (ML)

Question 2

T/F

A singleLeishmaniaspecies can produce more than one clinical syndrome, and each of the syndromes is caused by more than one species.

Answer 2

T

(The outcome in any one patient is a result of parasite factors (invasiveness, tropism, and pathogenicity) and the host’s genetically determined cell-mediated immune responses)

Question 3

Leishmaniasis is caused by protozoa ______________-

Answer 3

that survive and replicate inside vacuoles within macrophages and other mononuclear cell

Question 4

T/F

The leishmaniases are widely distributed across the tropical, subtropical, and temperate regions in 88 countries, 72 of which are in developing areas of the world

Answer 4

T

Question 5

T/F

3,500,000 people are at risk for getting leishmaniasis

Answer 5

F

350,000,000 people are at risk for getting leishmaniasis

Question 6

Approximately _____% of the world’s CL cases occur in Iran, Saudi Arabia, and Syria in the Middle East; in Afghanistan in Central Asia; and in Brazil and Peru in Latin America

Answer 6

90%

Question 7

90% of the cases of _____ leishmaniasis ccur in three Latin American countries: Bolivia, Brazil, and Peru

Answer 7

Mucosal leishmaniasis (ML)

Question 8

Describe the life cycle of leishmaniasis in the sandfly/human?

Answer 8

1. Sandfly takes a blood meal of and injects promastigotes into the skin of the human
2. Promastigotes are phagocytized by macrophages or other types of mononuclear phagocytoc ce;;s
3. Promastigotes transform into amastigoes
4. Amastigotes multiply in cells of various tissues and infect other cells in the human
5. Sandfly takes a blood meal
6. Cells eat the infected blood cells
7. Infected blood cells allow amastigotes to transform into promastigotes stage in the gut
8. In the sandfly they divide in gut

Question 9

Leishmaniasis is transmitted by what vector in the Americas and then else where?

Answer 9

Transmitted by female Lutzomiya sand flies in the Americas and Phlebotomus elsewhere

Question 10

Leishmaniasis vectors breed where?

Answer 10

• Breed in cracks in walls, trash, and mice nests

- Weak fliers and live near breeding sites

Question 11

T/F

Visceral leishmaniasis is a spectrum of symptoms and findings.

Answer 11

T

At one extreme are persons with asymptomatic, inapparent, or self-resolving infections.

At the other end are those with classic VL (kala-azar), who present with a characteristic pentad of prolonged fever, weight loss, hepatosplenomegaly, pancytopenia, and hypergammaglobulinemia

Question 12

What are the two extreme ends of the symptoms of Visceral leishmaniasis?

Answer 12

At one extreme are persons with asymptomatic, inapparent, or self-resolving infections.

At the other end are those with classic VL (kala-azar), who present with a characteristic pentad of prolonged fever, weight loss, hepatosplenomegaly, pancytopenia, and hypergammaglobulinemia

Question 13

Describe kala-azar presentation?

Answer 13

Present with a characteristic pentad of:

1. prolonged fever
2. weight loss
3. hepatosplenomegaly
4. pancytopenia
5. hypergammaglobulinemia

Question 14

Where do the organisms that cause Visceral leishmaniasis go inside the body?

Answer 14

Organisms live in macrophages and invade the reticuloendothelial system (bone marrow, liver, spleen)

Question 15

What are the two divisions of Cutaneous Leishmaniasis?

Answer 15

Old World - Eastern hemisphere

New World - Western hemisphere

Question 16

How does Cutaneous Leishmaniasis usually present?

Answer 16

Usually presents as a localized sore, sometimes spontaneously heals

(single or limited number of skin lesions)

Question 17

Definitive diagnosis of Cutaneous Leishmaniasis

Answer 17

• Definitive diagnosis requires demonstration of the parasite in a clinical specimen (usually skin) by histology, culture, or molecular analysis via polymerase chain reaction (PCR).
• To maximize diagnostic yield, ideally all three diagnostic tests are warranted on the initial sample if feasible.
• If not all tests can be performed, then histology and PCR may provide sufficient information. Parasitologic diagnosis to the level of theLeishmaniaspecies should be pursued, since this information may influence the determination of treatment

Question 18

How would one maximize diagnostic yield for cutaneous leishmaniasis?

Answer 18

Ideally, all three diagnostic tests are warranted on the initial sample if feasible

Question 19

T/F

diversity ofLeishmaniainfections makes standard treatment recommendations impossible

Answer 19

T

Question 20

What is the treatment of visceral Leishmaniasis in North America?

Answer 20

Liposomal amphotericin B is the drug of choice for the treatment of VL in North America and any other setting where it can be safely administered and cost is not limiting. It is the only drug licensed for the treatment of VL in the United States

Question 21

T/F

The U.S. Food and Drug Administration (FDA)-approved regimen for immunocompetent patients is 3.0 mg/kg/day on days 1 to 5, 14, and 21. A higher dose of 4.0 mg/kg/day on days 1 to 5, 10, 17, 24, 31, and 38 is recommended for immunocompromised patients

Answer 21

T

Question 22

In Latin America,____________ species of leishmaniasis is endemic and broadly distributed.

Answer 22

L. infantum/L. chagasi

Question 23

__________ is the major vector. Domestic dogs and wild foxes are reservoirs of infection

Answer 23

Lutzomyia longipalpis

Question 24

The type of team in the leishmaniasis case is?

Answer 24

Knotwork

(Services Involved:
HIV primary care
Dermatology -> biopsy
Infectious Disease-> treatment recommendations
Hospitalist-> patient care
Pathology-> read the bx)