Antimalarials Flashcards
What are the five falciparum spp.? (not really five anymore fyi)
Beyonce, not a circle, obvious, Chris’s worst one, vivacious
vivax malariae ovale knowlesi falciparum
What are the five falciparum spp? No prompts
vivax knowlesi malariae falciparum ovale
When we think of immune evasion, what stage of infection are we thinking of?
Internalisation within RBCs.
The life cycle form of parasites exiting from ruptures hepatocytes are called?
Merozoites.
In RBCs, the merozoites develops into uninucleate…
… ring trophozoite.
Uninucleate ring trophozoites develop into multinucleate X through asexual nuclear divisions.
Schizonts
Still in the RBC, multinucleate schizonts release numerous mononucleate…
… merozoites [again].
What stage of the malaria life cycle brings on the characteristic acute symptoms?
Emergence of merozoites from erythrocytes (also releases toxins).
What are the little green wormies and where do they come from?
SPOROZOITES and they come from nuclear divisions within the oocysts sitting on the outer wall of the mosquito GI lining.
What are three stages of the life cycle where the parasites undergo nuclear divisions?
Hepatic sporozoites -> merozoites
Erythrocytic ring trophozoites -> schizonts
Oocyts -> sporozoites
Malaria has historically killed M many people per year. In 2015 it was half that.
1 million.
P% of malaria deaths are in children under Q.
78%; <5yo
J is the most virulent plasmodium sp. but K is the most common.
falciparum; vivax.
Think dormant liver stage relapsing weeks (or even years) later?
[what are they called, which spp. do it?]
They’re called hypnozoites, and it’s VIVAX and OVALE.
Targeting hypnozoites is the idea of a new “radical cure” primaquine.
Uncomplicated clinical malaria presentation is non-specific and flu-like/febrile. Describe the stages of characteristic malaria attacks.
Easy to remember since it’s what happened to me in iso.
CYCLICAL - recur every two days or so (internal life cycle)
- cold stage
- hot stage
- sweaty stage.
What spp. would we use primaquine for and why?
Ovale and vivax - they’re hypnozoites and that what primaquine targets.
Are quinolines used for prophylaxis or intervention?
BOTH. They’re main use is intervention but they are still used as a typical prophylactic.
But NB only MEFLOQUINE that’s used as a prophylactic.
Quinine was originally purified from Cinchona bark extract. What is the side effects’ grouped term?
What are the five effects to remember?
Head, tummy, senses, skin, blood
Cinchonism.
GI upset, rashes, tinnitus & blurred vision, dizziness and rare thrombocytopaenia.
What are the five symptoms of Cinchonism (quinine side effects)? No prompts
GI upset, dizziness, blurred vision & tinnitus, rashes, rare thrombocytopaenia.
What kind of quinolone is the radical cure that kills hypnozoiteic ovale and vivax?
Primaquine is an 8-aminoquinolone.
Quinolones act by preventing the conversion of S to the non-toxic form T. They accumulate in the acidic food vacuoles because they are weak bases.
Ferric heme; haemozoin.
How have are chloroquine resistant parasites resistant?
They have evolved a way to EXCLUDE quinolines from the food vacuole.
Think poor absorption and obligatory fat ingestion for absorption? Also 99% protein bound.
Atovaquone.
Why does atovaquone have such an exessively long half life? 66-70h
Enterohepatic recycling.
