• Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

Card Range To Study

through

image

Play button

image

Play button

image

Progress

1/41

Click to flip

Use LEFT and RIGHT arrow keys to navigate between flashcards;

Use UP and DOWN arrow keys to flip the card;

H to show hint;

A reads text to speech;

41 Cards in this Set

  • Front
  • Back
What is essential to diagnose Malaria?
History of travel to endemic area
Periodic attacks of chills, fever and sweating
Headache, myalgia, splenomegaly, anemia, leukopenia
Characteristic parasites in erythrocytes: I.D. via thick or thin film Giemsa Stain
What are the relapsing Malarias?
Vivax

Ovale

hide in liver
which malaria is the most deadly?
falciparum
When do you take the blood smear?
take it during fever phase: fever due to cell rupture
Transmission via:
1. human to human anopheles mosquito

2. Transplacental Transmission

3. Infected blood transfusion
Stages of Plasmodium Life Cycle
Tissue Phase
1. carrier mosquito injects the sporozoite into a human

2. Sporozite is transformed into merozoite in the liver

3. The merozoites enter into the blood stream adn parasitizes the RBC; organism is called a blood schizont

4. Erythrocyte lysis occurs with release of gametocytes

5. Non-carrier mosquito ingests the gametocytes by biting an infected man
2 Life cycles of malaria
1. asexual in humans

2. sexual in mosquito
What phase do you take prophylactics?
Preexoerythrocytic Phase: when the sporozoite is in the liver or in the mosquito
Primary Erythrocytic Phase
common to all malaria

use Chloroquine (quinolenes) in this phase
Secondary Exoerythrocytic Phase
Vivax and Ovale

reinvade liver

need to treat with/2 varieties
1. tissue---> primoquine
2. blood----> chloroquine
Fevers in Ovale, Malaria, Falciparum, Vivax
Every other day
Vivax
Falciparum
Ovale

Every 3rd Day
Malaria

Due to rupture of blood cells and pyrogenes being released
Complications of Falciparum Malaria
Cerebral Malaria
Hyperpyrexia
Hemolytic anemia
Convulsions
Dysenteric or Cholera like stools
Dark Urine and Anuria
Hypoglycemia
Chloroquine
4-aminoquinoline

drug of choice for all forms of malaria except chloroquine resistant forms of falciparum

decreased accumulation of the drug in the parasite

well absorbed and concentrated in the liver, kidney, lungs, RBCs and brain

kidney excretion

acts on erythrocytic stage
Chloroquine MOA
enters parasite by energy dependent mechanism

accumulates in food vacuole of plasmodium

prevents polymerization of hemoglobin; break down product heme is toxic to the parasite
What happens in Chloroquine resistance?
parasites expel drug via a membrane P-glycoprotein pump.
Chloroquine USE
used in acute cases

prophylaxis: chloroquine + primaquine

amebic liver abscess: chloroquine + emetine

collagen disorder: anti-inflammatory: SLE, R.A.

can be used in pregnancy
What do you use with persistent stage malaria or relapse
Primaquine
Chloroquine Toxicity
dizziness, blurred vision, retinal damage, headache, diarrhea, GI-irritation, epigastric pain, exfoliative dermatitis, neuropathy, and auditory impairment

Myocardial depression

c/i: psoriasis and porphyria
Primaquine
8-aminoquinoline

used in exoerythrocytic phase (liver) (vivax or ovale-dormant)

called a tissue schizonticidal agent

no effect in acute attacks
What effect does primaquine have on a G6PD deficient individual?
primaquine is a cellular oxidant (the drug forms quinoline-quinone metabolite) and causes hemolysis
Primaquine AE
GI, nausea, vomiting, epigastric pain, abdominal cramps. Headache, agranulocytosis, pruritis, methemoglobinemia

prophylaxis in endemic areas of ovale and vivax
Antifolates
Pyrimethamine and Proguanil

Sulfadoxine and Dapsone: oral route and urinary elimination

inhibits dihydrofolate reductase
Proguanil + Atovaquone (Malarone)
used in the prophylaxis of resistant falciparum sp.
Pyrimethamine + Sulfadoxine
synergistic sequential blockade in folate pathway

used as prophylaxis in chloroquine sensitive regions

used in toxoplasmosis

MOA similar to smz+tmp
Antifolates: AE
high doses of pyrimethamine can result in megaloblastic anemia

sulfas-crystalluria, hemolysis, Steven-Johnson syndrome
Quinine
alkaloid derivative from bark of cinchona tree

i.v. admin in severe infections

also absorbed well via oral
Quinine MOA
complexes with double stranded DNA and prevents separation of strands, thus preventing DNA replication and transcription
What is quinine used with to shorten therapy and limit toxicity?
doxycycline
clindamycin
pyrimethamine

used in CRPF
What can be used instead of quinine? and What kind of medicine is it primarily?
Quinidine

antiarrythmatic
Quinine Use
1. resistant form of p. falciparum
2. nocturnal leg cramps associated with arthritis, diabetes, atherosclerosis and thrombophlebitis
3.Myotonia Congenita: reducing response to Ach and as a sclerosing agent: relaxes muscles
Quinine AE
Cinchosim: headache, vertigo, tinnitus, blurred vision, GI distress---> dose dependent

Cardiac conduction abnormalities

Black water fever: intravascular hemolysis occurs in quinine sensitized patients

hypoglycemia---> pancreas is stimulating to produce insulin

c/i in pregnancy: categorized as X
Drugs in Category X
Thalidomide
Clomiphene
Ergot
Ethionamide
HMG-CoA
reductase inhibitors
isotrentinoin
mebendazole
halofantrine
ribavarin
misoprostol
Category D drugs:
potential benefit to harm is greater in Pregnancy and may outweigh the risk: used with caution

aminoglycosides
tetracyclines
fluroquinolones
Mefloquine
first line drug for prophylaxis

synthetic 4-quinoline

MOA: not known

long half life (6 days) due to enterohepatic circulation

well absorbed from GI tract and 20% excreted unchanged
Mefloquine AE
toxicity: cardiac conduction abnormalities, pyschiatric abnormalities, neurological abnormalities, seizures
Halofantrine
MOA not known

effective against all 4 malarial species including CRPF species.

effective in erythrocytic phase
Halofantrine AE
cardiotoxicity: QT prolongation
embryotoxicity
Doxycycline
good prophylactic agent in areas with chloroquine resistant and mefloquine resistant P falciparum
Artemether
ginghaosu or wormwood

effective in chloriquine-resistant p. falciparum

metabolized in the food vacuole of parasite forming toxic reactive free radicals

blood schizonticidal agent

short half life so no prophylaxis

Artesunate is similar
Atovaquone
inhibits electron transport system-ATP synthesis

complex-3 of electron transport system

resistance is not seen

active against PCP, trophozites and cyst forms of T.Gondii
Pregnancy and Antimalarials
advised not to travel to endemic areas

Mefloquine recommended in pregnancy if traveling to chloroquine resistant areas

Chloroquine or hydroxychloroquine are safe in pregnancy, if traveling to endemic active against P. Falciparum