Friday - Krafts 4 - malaria

Question 1

what type of mosquito carries plasmodia protozoa

Answer 1

anopheles mosquito (looks like it’s poised to strike)

culex doesn’t (it doesn’t like its poised to strike)

Question 2

what do you see when you look at the blood smear of someone with malaria

Answer 2

plasmodium trophozoites (look like little grey rings with a ruby on them)

Question 3

what species of plasmodium is the most harmful
most common?
which relapses

Answer 3

most harmful: plasmodium falciparum
most common: p.vivax, p.falciparum
relapses: p. vivax, p. ovale

Question 4

3 forms of the plasmodium in the exoerythrocytic cycle. In what cells is it happening?

Answer 4

in hepatic cells

enters as sporozoites
becomes schizonts
leaves and merozoites

Question 5

4 forms of the plasmodium in the erythrocytic cycle. what cells is this happening in

Answer 5

enters red blood cell and merozoite

becomes ring form,
trophoszoite,
schizont,
merozoite (a type of schizont) (can arrange themselves in rosettes in falciparum)

Question 6

what is the meaning of falciparum

Answer 6

falx - curved thing (the mature gametocytes look sickle shaped)
parum - to give birth to

Question 7

What do you see that is characteristic in the trophozoites

Answer 7

Schuffner’s dots

Question 8

main cause of death in children who have p. falciparum

Answer 8

cerebral ischemia - blood flow is impeded because infected red cells adhere to endothelium of vessels (also, RBCs form rosettes or clumps)

Question 9

pathology of malaria

Answer 9

enlarged spleen
super active macrophages
fibrosis, grayish color if chronic

liver enlarged and pigmented

brain vessels get plugged

Question 10

Sx of malaria

Answer 10

incubation 1-2 weeks
prodrome - flu like sx
Paroxysms! Fever/chills, sweating, myalgia

Question 11

inherited red cell alterations leading to host resistance

Answer 11

hemoglobinopathies
thalassemias
G6PD deficiency
RBC antigens (ABO, Duffy)

Question 12

how do you diagnose malaria

Answer 12

blood smear

Question 13

Radical cure for malaria

Answer 13

primaquine - kills the hepatic forms

Question 14

suppressive prohylaxis of malaria

Answer 14

Chloroquine - accumulates in the acid pH of the food vacuole of the infected RBC, where the parasite digests the heme. There, it stops the degredation of ferriprotoporphyrin IX (FPIX), which builds up and is toxic to the infected cell.

in chloroquine resistant areas: Atovaquone/proguanil, doxycycline or mefloquine

Question 15

Tx of acute attack in chloroquine resistant p. falciparum

Answer 15

quinine + doxycyclin

Question 16

Quinidine

Answer 16

anti-arrhythemic drug that blocks Na and K currents/

IV for severe malaria

Question 17

mefloquine

Answer 17

probably acts like chloroquine

chloroquine is preferred because this can cause neurophyciatric reactions

Question 18

Artemisinins

Answer 18

rapid and potent against multi drug resistant non hepatic forms

don’t give alone to avoid selection of resistant organisms