Term
what is the most deadly spp of plasmodium? where is it found? |
|
Definition
plasmodium falciparum - found in africa |
|
|
Term
which pts are resistant to infection by plasmodium vivax? |
|
Definition
pts who lack the duffy coat receptor for binding |
|
|
Term
which forms of plasmodium can cause relapsing malaria? why? |
|
Definition
vivax and ovale - b/c they form hypnozoites |
|
|
Term
what kind of parasite is plasmodium? |
|
Definition
|
|
Term
what is the usual route of transmission for malaria? |
|
Definition
female anophelene mosquitoes |
|
|
Term
what is the simplified plasmodium lifecycle? |
|
Definition
an infected female anophelene mosquito is itself infected, it then bites a human and injects sporozoites which go to the liver and mature through an asexual cycle and are released as merozoites which infect the RBCs |
|
|
Term
why is malaria vaccine hard to produce? |
|
Definition
b/c the life cycle is complex and there are many antigenic changes |
|
|
Term
what is the MOA for the anti-malarial chloroquine? |
|
Definition
plasmodium has to convert heme (which is toxic to it) into hemazoin during its intra-erythrocytic phase, and chloroquine blocks this conversion. |
|
|
Term
what kind of immunity do pts living in countries where malaria is endemic have? |
|
Definition
partial and non-sterilizing, due to repeated challenges. they are for the most part immune, but if they leave their country, they become naive |
|
|
Term
what is a common side effect of chloroquine? |
|
Definition
hypotension, pruritis in africans, and hair hypopigmentation |
|
|
Term
how was quinine administered before its rx-potential was known? where does it come from? |
|
Definition
as a tea, quinine comes from the cinchona tree |
|
|
Term
what is the MOA for quinidine? |
|
Definition
same as chloroquine: plasmodium has to convert heme (which is toxic to it) into hemazoin during its intra-erythrocytic phase, and quinine blocks this conversion. |
|
|
Term
|
Definition
tinnitus, headache, dizziness, impaired high tone hearing, vertigo, uticaria, skin flushing, fever, dysphoria, and visual disturbances |
|
|
Term
what are the ADRs for quinine? |
|
Definition
cinchonism, hypoglycemia (due to parasites consumption of glucose/release of insulin from pancreas by quinine), blackwater fever (massive hemolysis due to malaria/anti-malarials, presents as hematuria and esp in G6PD pts), and hemoglobinuria |
|
|
Term
when is malaria a medical emergency? |
|
Definition
when more than 5% of RBCs are parasitized |
|
|
Term
why are anti-malarials so greatly researched? |
|
Definition
so western countries can fight in tropical areas |
|
|
Term
can mefloquine/lariam be given prophylactically or as tx? |
|
Definition
|
|
Term
what are the ADRs for mefloquine/lariam? |
|
Definition
|
|
Term
what happens if a pt vomits after taking mefloquine/lariam? |
|
Definition
they should repeat the dose if it was w/in the first hr |
|
|
Term
|
Definition
a fixed dose combination of atovaquone (also used in pneumocycstis jirovecii, t. gondii, babesia microti) and proguanil |
|
|
Term
what are ADRs for malarone? |
|
Definition
skin rash, insomnia, hyponatremia - will interact with other rxs. also not recommended in children or pregnant/breastfeeding women due to renal impairment |
|
|
Term
what is useful about malarone? |
|
Definition
you can start it the day before you need it |
|
|
Term
what other disease besides malaria is dapsone used in? |
|
Definition
|
|
Term
what is dapsone syndrome? |
|
Definition
rash, fever, jaundice, and eosinophilia |
|
|
Term
can tetracycline/doxy be used against malaria? what might ADRs be? |
|
Definition
yes, for tx/prophylaxis. ADRs: photosensitivity, tooth discoloration, and cannot be used in children <9 or pregnant women |
|
|
Term
what drug is used for plasmodium vivax and ovale, the spp responsible for hyponozoite formation/relapsing malaria? |
|
Definition
|
|
Term
what is an ADR for primaquine? |
|
Definition
it can cause hemolytic anemia in pts with G6PD deficiency (which is how the disorder was discovered) |
|
|
Term
what drugs work at the hepatic stage of the schizonticide? |
|
Definition
|
|
Term
what drugs work at the blood stage of the schizonticide? |
|
Definition
malarone, doxy, mefloquine, choroquine |
|
|
Term
is plasmodium falciparum drug resistant? |
|
Definition
yes, it is amount the top 10 |
|
|
Term
what is beneficial about the combination pill of artesunate and mefloquine? |
|
Definition
it is color coded and pts only have to take it x2/day -> better compliance |
|
|
Term
what are the artemisinins? |
|
Definition
lactones extracted from sweet wormwood which is a potent and rapidly acting blood schizonticide. derivatives are artemether, artemotil, and artesunate. it was even prescribed by chinese physicians. |
|
|
Term
what is one reason for resistance to anti-malarials? |
|
Definition
HIV initially presents as a fever, so it is over prescribed |
|
|
Term
what is useful about combining arteminsins with other anti-malarials? |
|
Definition
they can attack different portions of the parasite's life cycle |
|
|
Term
which drugs can be prescribed to pregnant pts? |
|
Definition
chloroquine, quinine (abortive in high dosages), and clindamycin |
|
|
Term
which are the big 3 anti-malarials? |
|
Definition
mefloquine, doxy, and malarone |
|
|
Term
what is complicated malaria? |
|
Definition
this is a medical emergency and involves: unarousable coma, hypoglycemia, oliguria, renal failure, DIC, ARDS, circulatory shock, severe anemia, PE, and jaundice |
|
|
Term
what is tx for complicated malaria? |
|
Definition
quinidine gluconate or artesunate |
|
|
Term
what is metronizadole (or tinidazole) good for? ADRs? |
|
Definition
anaerobic, protozoan, and H. pylori. ADRs: disulfiram-like effect (abd distress, vomiting, flushing, headache if pts drink alcohol w/in 3 days) |
|
|
Term
what is pentamidine good for? |
|
Definition
pneumocystis jirovecii via inhaled aerosol |
|
|
Term
what is nitazoxanide good for? |
|
Definition
cryptosporidiosis and giardiasis |
|
|
Term
what is furazolidone good for? |
|
Definition
|
|
Term
what is paromomycin good for? |
|
Definition
amebiasis (it is a luminal agent like idoquinol) |
|
|