Flashcards in 18a Treatment for Parasitic Infection (Malaria) Goad Deck (53):
What are Nematodes?
What are Trematodes?
What are Cestodes?
What are some laboratory tests for Parasitology?
Ova and Parasites (O&P: stool specimen, eggs, cysts, trophs, larvae). Examination (pinworms). CBC (Eosinophilia: Helminths, not Protozoal). Entero-test (string test). Thick and thin blood films - malaria and filaria. Giemsa stains
What is usually done at a Pre-Travel Health Clinic?
Ideally 6 weeks before departure. 30 minute consultation. 15 minutes for vaccinations. Prescriptions filled while drawing up vaccines. Individuals or groups
What are the different species of Plasmodium?
P. vivax, P. ovale, P. falciparum, P. malariae, P. knowlesi
Which Plasmodium is most severe?
P. falciparum > vivax > malariae > ovale
Which Plasmodium causes the highest rate of anemia?
P. falciparum > vivax, malariae > ovale
What is autochthonous malaria?
Indigenous: mosquito borne transmission of malaria in geographic area where malaria occurs regularly. Introduced: mosquito borne transmission of malaria from a person with an imported case in an area where malaria does not occur regularly
What is Induced Malaria?
Malaria acquired through artificial means, i.e. blood transfusion, shared needles
What is Relapsing Malaria?
Renewed manifestations > 45 days after a previous malaria case
What is Cryptic Malaria?
A case of malaria for which epidemiologic investigations fail to identify a plausible mode of acquisition
What is the clinical picture of Malaria?
10-14 day incubation. FEVER, HA, DIARRHEA, malaise, chills, and sweats. Periodic fever an uncommon finding. Labs: THROMBOCYTOPENIA, ELEVATED LFTs, normal hb/hct/WBC
What is the primary type of malaria seen in patients when they come in after 42 days of being infected?
What malaria drugs are used for Primary (Causal Protection), liver cycle?
Atovaquone. Primaquine. Tafenoquine
What malaria drugs are used for the Erythrocytic Cycle?
Atovaquone. Azithromycin. Chloroquine. Doxycycline. Mefloquine. Proguanil. Tafenoquine
What malaria drugs are used for Relapse?
Primaquine, Tafenoquine (not available in the US)
What is Coartem?
Artemether + Lumefantrine
For malaria chemoprophylaxis, what is used for Chloroquine-sensitive P. vivax malaria?
Chloroquine. Hydroxychloroquine sulfate. Primaquine
How is Chloroquine dosed for malaria chemoprophylaxis?
500mg PO once/week in adults. 8.3mg/kg PO once/week for children
What is the sig for Chloroquine dosed for malaria chemoprophylaxis?
Start 1-2 weeks before entering malarious area, then weekly in malarious area, then weekly x4 weeks after leaving the area
How is Hydroxychloroquine sulfate dosed for malaria chemoprophylaxis?
400mg PO once/week for adults. 6.5mg/kg PO once a week for children
What are the general characteristics of Chloroquine (Aralen)?
4-aminoquinoline. High resistance. Schizonticidal: erythrocytic only. Relatively safe during pregnancy
What are the ADRs associated with Chloroquine?
Retinopathy (high dose), psychosis (rare), and itching, wide QRS complex (rare), exacerbate psoriasis and porphyria
What caution needs to be used with Chloroquine?
Caution in G-6-PD deficiency (testing NOT required). Pregnancy Category C, but CDC recommends use when needed
What are the general characteristics of Primaquine?
8-aminoquinoline. Tissue schizonticidal (exoerythrocytic)
What is Primaquine used for?
Prophylaxis (off label) and relapse prevention (terminal prophylaxis and radical care). Against: P. vivax and P. ovale. Daily during last 2 weeks of post departure schedule
What is a contraindication for Primaquine use?
G-6-PD deficiency. MANDATORY testing. More likely in African American, Mediterranean, Asian. Results in hemolytic anemia
What drugs are often used in malaria chemoprophylaxis in chloroquine-resistant P. falciparum malaria (CRPF)?
Mefloquine. Doxycycline. Azithromycin (less effective than others)
How is Mefloquine dosed for malaria chemoprophylaxis?
250mg PO once/week in adults. 5mg/kg PO once/week in children
How is Doxycycline dosed for malaria chemoprophylaxis?
100mg PO once/day in adults. 2mg/kg PO once/day in children > 8 years of age (contraindicated < 8 years of age)
What are the ADRs associated with Doxycycline?
GI, esophagitis (caps > tabs), vaginal candidiasis
What are the general characteristics of Mefloquine (Lariam)?
Used for Chloroquine resistant Plasmodium (especially P. falciparum). Schizonticidal; erythrocytic phase only
What are the DDIs associated with Mefloquine?
Typhpoid vaccine PO; cardiac drugs
What are the ADRs associated with Mefloquine?
Neuropsychiatric (HALLUCINATIONS, convulsions (CI'd in seizure patients), TREMOR, vertico), CV. Pregnancy Category C, but CDC recommends use when needed
What is used for malaria chemoproplylaxis is Chloroquine-resistant P. falciparum malaria (CRPF) and Mefloquine-resistant Pf (MDR PF or MRPF)
Atovaquone + Proguanil (Malarone). Doxycycline
How is Atovaquone + Proguanil (Malarone) dosed for malaria chemoprophylaxis?
250mg + 100mg fixed dose combination
What is the sig for Atovaquone + Proguanil (Malarone) in malaria chemoprophylaxis?
Take 1 tab QD starting 1-2 days before entering malarious area, daily while at risk, then daily for 7 days after departing malarious area
What are the general characteristics of Atovaquone/Proguanil (Malarone)?
Chloroguanide = Proguanil (Proguanil converts to Cycloguanil = active form, up to 20% less conversion in Asian and AA). Take with food (or milky drink)
What are the DDIs associated with Atovaquone/Proguanil?
Rifampin, Rifabutin, TCN, Reglan decrease efficacy. Pregnancy Category C - do not use in pregnancy
How is Atovaquone/Proguanil used in "standby therapy"?
Presumptive treatment and prophylaxis of P. falciparum: 4 tabs QD x3 days
What is the general scheduled use of Mefloquine for malaria chemoprophylaxis during a trip?
1-2 weeks before trip. Weekly during trip. 4 weeks after trip
What is the general scheduled use of Doxycycline for malaria chemoprophylaxis during a trip?
1-2 DAYS before trip. Daily during trip. 4 weeks after trip
What is the general scheduled use of Chloroquine for malaria chemoprophylaxis during a trip?
1-2 weeks before trip. Weekly during trip. 4 weeks after trip
What is the general scheduled use of Malarone for malaria chemoprophylaxis during a trip?
1-2 DAYS before trip. Daily during trip. 1 week after trip
For Malarone, use caution with...
For Doxycycline, use caution with...
Pregnancy, children, sun, esophagitis, DDIs
For Mefloquine, use caution with...
CV, Psych, CNS, Seizure
For Chloroquine, use caution with...
Eye, QT, psoriasis
What drugs need to be used if targeting blood-staged schizonticide AND gametocytocide?
What are the common drugs and their doses used for Chloroquine-resistant P. falciparum or Chloroquine-resistant P. vivax?
Mefloquine 2 doses over 12hrs. Quinine + Doxycycline Q8hrs x3days + BID x7 days. Atovaquone/proguanil 4 tabs QD x3 days. Artemether/Lumefantrine x3 days
What are some general characteristics of Coartem (Artemether and Lumefantrine)?
Rapid kill w/ artemether; sustained kill with lumefantrine. Not used for prophylaxis, only treatment. Cure rate up to 90% at 28 days. Many DDIS