Hunter: Schistosomiasis/Malaria Flashcards Preview

Block 7 Week 4 > Hunter: Schistosomiasis/Malaria > Flashcards

Flashcards in Hunter: Schistosomiasis/Malaria Deck (33):
1

What are the 3 major schistosomes?

Schistosoma mansoni
S. japonicum
S. haematobium

2

What are the 2 minor schistosomes?

Schistosoma mekongi
S. intercalatum

3

What is the infectious form in humans for schistosomes? Through what route do they invade the human? What is the reservoir?

cercariae; penetrate the skin; snail is the reservoir

4

Cercarial penetration of skin can cause a transient (blank)
Migration of schistosomules through lungs can cause a (blank) that can be severe in heavy infections
Adult worms in superior mesenteric veins (mansoni and japonicum) and vesicle plexus of bladder (hematobium) cause (blank)

dermatitis; pneumonitis; no clinical symptoms

5

Onset of egg production causes (blank) (allergic response);

Intestinal or urinary bladder symptoms are due to (blank) passing through tissue to lumen; cause severe hemorrhagic cystitis and gastroenteritis

Eggs swept up portal circulation to liver cause (blank); T cell-mediated delayed hypersensitivity reaction to the eggs  

Blockage of sinusoids leads to pipestem fibrosis and (blank)

Katayama fever; eggs; granulomas; portal HTN

6

3 clinical lab findings in schistosomiasis?

hepatosplenomegaly
eosinophilia
hyperimmunoglobulinemia

7

List the three symptoms of disease caused by schistosomes

liver and spleen granulomas
fibrosis
inflammation

**all due to eggs trapped in tissues

8

What drug do you use to treat schistosomes?

praziquantel

9

This schistosome causes inflammation and fibrosis of the bladder and ureters; obstruction of the ureters leads to hydronephrosis and eventually to uremia

Schistosoma hematobium

10

These two schistosomes are more likely to infect the gut than the urinary bladder

S. mansoni and japonicum

11

Compare the structures of S. hematobium, japonicum, and mansoni eggs

S. hematobium: egg comes to a point on one end
S. japonicum: more rounded egg with a tiny bleb hanging off
S. mansoni: spiky bleb coming off of egg

12

In the life cycle of plasmodium spp, the infectious form delivered from the bite of a mosquito is the (blank). This enters the bloodstream where it is now called a (blank). If it is in the latent stage, it is called (blank). When it infects the liver it is a (blank). When liver cells rupture, they release (blank); when the mosquito takes a meal, it ingests (blank)

sporozoite; merozoite; hynozoite; trophozoite --> schizont; merozoites; gametocytes

13

When the parasite is undergoing its asexual life cycle in the LIVER from a trophozoite to a schizont, are there any symptoms? When the parasite is undergoing its asexual life cycle in the BLOOD, are there symptoms?

no, no clinical disease during liver stage; yes clinical disease when parasite is in blood

14

What is the main cytokine responsible for the systemic inflammatory disease that is malaria?

TNF-alpha

15

What causes the classic fever in malaria?

rupture of RBCs

16

How often do the fevers occur in the following:

P. falciparum
P. vivax
P. ovale
P. malariea

P. falciparum: daily (malignant tertian)
P. vivax: every other day (benign tertian)
P. ovale: every other day (ovale tertian)
P. malariae: every third day (quartan)

17

3 important clinical findings in malaria?

anemia
hepatosplenomegaly
hyperimmunoglobulinemia

18

Which forms of malaria RELAPSE (liver hynozoites re-establish infection)?

Which forms of malaria do not relapse, but RECRUDESCE (subclinical infection becomes clinical disease)?

vivax and ovale relapse;
falciparum and malariae recrudesce

19

The most common cause of sepsis and septic shock in the world

plasmodium falciparum

20

What are these?

cerebral coma (schizonts sequestered in brain)
anemia
pulmonary edema
renal failure
shock
lactic acidosis
hypoglycemia
tropical splenomegaly
maternal death/stillbirth/low birth weight

glomerulonephritis

splenic rupture

complications of P. falciparum

complications of P. malariae

complications of P. vivax

21

What do malarial parasites do to the shape of the RBC?

they alter the morphology, create knobs

22

How can you diagnose malaria?

thick and thin blood films

23

T/F: Mixed infection with P. falciparum and P. vivax can occur

true

24

Which form of malaria has multiple ring stages and appliqué forms

P. falciparum

25

Which form of malaria has enlarged erythrocytes with stippling

Plasmodium vivax

26

Which RBC antigen can determine your susceptibility to vivax malaria?

Duffy blood group

**duffy + (FyA)

27

Heterozygotes with this condition have increased survival in malaria

sickle cell trait: HbA/HbS

28

This allele is protective against malaria in West Africa

HLA-B53

29

This drug kills erythrocytic forms of malaria

chloroquine

30

This drug kills hepatic forms of malaria (liver hypnozoites) and prevents relapses with vivax and ovale

primaquine

31

T/F: Drug resistance in malaria is widespread; particularly chloroquine resistance

True

32

What is used for travelers to prevent malaria?

chemoprophylaxis

33

Why has malaria not been eradicated?

drug resistant forms of the parasite
mosquito resistance to DDT
Wars and massive population movements
Difficulties in obtaining sustained funding from donor countries
Lack of community participation in host countries