L28: Parasitology

Question 1

What are protozoa

Answer 1

single celled eukaryotes

Question 2

cell structure similar/different to?

Answer 2

• similar humans and plants (DNA nucleus bound)
• different to bacteria and protozoa

Question 3

what is special about protozoa transmission

Answer 3

involves more than one species

Question 4

what causes malaria

Answer 4

plasmodium falciparum

Question 5

what causes toxoplasmosis

Answer 5

toxoplasma gondii

Question 6

what causes giardiasis

Answer 6

giardia lamblia

Question 7

How is giardiasis commonly manifested

Answer 7

food poisoning, indigestion

Question 8

giardia lamblia infects what?

Answer 8

enterocytes of the small intestine

Question 9

how is giardia acquired

Answer 9

contaminated water

Question 10

symptoms of giardia lamblia

Answer 10

watery diarrhoea

Question 11

what does giardia do?

Answer 11

disrupts projections on enterocytes (vili?), disruption of nutrient absorption

Question 12

trophozoites

Answer 12

parasites in eating phase

Question 13

what happens when giardia is in an unfavourable environment

Answer 13

develops cyst wall around itself - protection, survival

Question 14

life cylce of giardia

Answer 14

cyst swallowed - SI - to LI - cyst formation - shat out

Question 15

diagnosis and treatment of giardia

Answer 15

• cysts in faeces
• metronizadole

Question 16

toxoplasma gondii infects

Answer 16

gut of various cat species

Question 17

what is the mechanism of survival of t. gondii

Answer 17

oocyte/cyst formation - like giardia

Question 18

how can humans get infected with toxoplamsa gondii

Answer 18

• eating oocytes in cat faeces
• eating uncooked meat

Question 19

cycle of infection of toxoplasma gondii

Answer 19

infected cat - poop with organism - other organism infected by ingestion of organism - source of infection for next generation (can be rats, sheep - uncooked meat etc)

Question 20

where does toxoplasma gondii like to reside/multiply

Answer 20

brain

Question 21

toxoplasmosis how much percent is infected?

Answer 21

30%

Question 22

when in life is toxoplasma gondii usually caught

Answer 22

childhood

Question 23

symptoms of toxoplasmosis

Answer 23

• mild, swollen lymph nodes, fever - non specific

Question 24

HIV relation to toxomplasmosis

Answer 24

untreated HIV can lead to toxoplasma gondii causing brain abcesses

Question 25

how does toxoplasma gondii affect vision

Answer 25

affect retina, scar tissue, blind spot

Question 26

Toxoplasmosis diagnosis

Answer 26

1. serolology - IgM = acute infection (new AB, current) - IgG = chronic infection 2. PCR for DNA in CSF 3. Radiology 4. Opthalmoscopy appearances

Question 27

Toxoplasmosis treatment

Answer 27

usually none for acute - pregnant or AIDS --> sulphadiazine + pyramethamine

Question 28

What cuases potentially fatal malaria

Answer 28

plasmodium falciparum

Question 29

what causes benign malaria

Answer 29

plasmodium vivax

Question 30

what are the common malaria

Answer 30

plasmodium vivax plasmodium falciparum

Question 31

plasmodium falciparium

Answer 31

malaria - potnetially fatal

Question 32

how is malaria transmitted

Answer 32

mosquitoes

Question 33

what mosquito transmits malaria

Answer 33

anopheles

Question 34

life cycle of malaria

Answer 34

mosquito - sucks blood from human - mosquito secretes saliva (anticoagulant) - parasite in glands - infected human - travel through blood - enter liver cells - ultimate target is RBC - exit liver to rbc

Question 35

malaria causes what symptoms

Answer 35

rigors, fever, shivering, sweating, headache

Question 36

malaria diagnosis

Answer 36

blood microscopy analysis

Question 37

P. falciparum differs from P. vivax in terms of RBC

Answer 37

- P. falciparum can infect any circulating RBC - high % infected RBC - severe disease - P. vivax only infect immature/young RBC - small % infected RBC - mild disease

Question 38

P. falciparum infected RBC - consequence on capillary

Answer 38

surface of RBC gets chancges, expression of molecules, stick to capillary cells - clump up and block cappillaries - affect brain and kidney perfusion - **sequesteration?**