Malaria Module - Krafts

Question 1

Where is malaria most prevalent?

Answer 1

Sub-Saharan Africa (90% of deaths)

Question 2

What causes malaria?

Answer 2

Plasmodium, a Protozoa

Question 3

What is the cause of the pigmentation in infected malarial cells?

Answer 3

Hemoglobin is broken down to alpha-hematin, which is toxic and pink. Then the parasite converts the hematin to hemozoin.

Question 4

What mosquito transmits malaria?

Answer 4

Anopheles Mosquito

Question 5

What are the 3 plasmodium that have a low parasite burden and cause a mild anemia?

Answer 5

Plasmodium vivax (relapse)
Plasmodium ovale (relapse)
Plasmodium malariae

Question 6

What is the plasmodium that has a high parasite burden, causes severe anemia, and has a high fatality rate?

Answer 6

Plasmodium falciparum (causes cerebral and multi-organ symptoms)

Question 7

What are the most common plasmodium?

Answer 7

Plasmodium falciparum

Plasmodium vivax

Question 8

What is the infectious stage of the plasmodium?

Answer 8

Sporozoites that infect the liver to form hepatic schizonts

Question 9

What is a trophozoite?

Answer 9

After the ring form, the trophozoite begins to reproduce the protozoan particles.

Question 10

What is a merozoite?

Answer 10

The infectious particles that can go on to infect other cells.

Question 11

What plasmodium are Schuffner’s dots found in?

Answer 11

P. ovale and P. vivax

Question 12

What plasmodium are enlarged red cells found in?

Answer 12

P. ovale and P. vivax

Question 13

Why is malaria from Plasmodium falciparum worse?

Answer 13

Red cells of any age can be infected

Question 14

Characteristics of Plasmodium falciparum red cell pathology

Answer 14

Rosettes
Abnormal binding to endothelium
Blood flow impeded

Question 15

What is the main cause of death in children from Plasmodium falciparum?

Answer 15

Cerebral ischemia

Question 16

What are some of the symptoms caused by Plasmodium falciparum that are attributed to TNF, INF-y, IL-1?

Answer 16

Suppress red cell production
Causes fever
Tissue damage
Red cell binding to endothelium

Question 17

How does the spleen become enlarged in a malarial patient?

Answer 17

Super-active spleen macrophages eat the red cells infected with parasites

Causes fibrosis, grayish color

Question 18

How do the brain vessels become plugged up in a malarial patient?

Answer 18

Red cell rosettes
Hypoxia around vessels
Ischemia

Question 19

What happens to the liver in a malarial patient?

Answer 19

Enlarged and Pigmented liver

Question 20

What is the time frame for infection?

Answer 20

Incubation 1-2 weeks
Prodrome: flu-like illness
Paroxysms with fever, chills, sweating, myalgia

Question 21

Describe Quotidian fevers and what causes it.

Answer 21

Fevers daily with P. falciparum

Question 22

Describe Tertian fevers and what causes it.

Answer 22

Fevers every 48 hours with P. vivax and P. ovale

Question 23

Describe Quartan fevers and what causes it?

Answer 23

Fevers every 72 hours with P. malariae

Question 24

What are some inherited red cell alterations that can help in resistance to malaria?

Answer 24

Hemoglobinopathies (sickle cell)
Thalassemias
G6PD deficiency
RBC antigens (ABO, Duffy)

Question 25

How can partial immune mediated resistance help in resistance to malaria?

Answer 25

Develops over time in patients in endemic areas Reduces severity of disease P. falciparum uses antigenic variation

Question 26

How is malaria diagnosed?

Answer 26

1) Clinical symptoms with appropriate history 2) Identify plasmodia in RBC on regularly-stained blood smear (gold standard) 3) Rapid immunochromatographic tests (quicker, but less accurate)