Blood Protozoa Flashcards
What are the Blood Protozoa
Malaria and Babesiosis
What kills more children under 5 than any other organism?
Plasmodium Falciparum
What are the 5 plasmodial species that cause disease in humans?
Falciparum, Knowlesii, Malariae, Ovale and Vivax
What is the life form of malaria transmitted to humans?
Sporozoites. They are cleared from the blood and enter the liver and lymph nodes within 20 minutes
Sporozoites transform into what form after 10 to 14 days?
Merozoites. These enter RBCs which later become schizonts.
Some schizonts transform into another life form. What is it?
Gametocytes
How many stages of infection are there?
3
What are the three stages?
- cold shaking chills, 2.Hot and dry, 3.diaphoresis, fatigue and resolution of fever.
What are the fever patterns?
Tertian-vivax and ovale, Quartan-malariae, Malignant Tertian-Falciparum
What are the signs of malaria in adults?
Tachycardia,Tachypnea,Pallor,Ill appearance and Splenomegaly
What are the signs of malaria in children?
Fever, Kussmaul’s Sign, Jaundice, Dehydration sx include nausea, vomiting and diarrhea, malaise, headache
How many classes of Anti Malarial Drugs?
7
What are the classes?
4-Aminoquinolones, 8 Aminoquinolones, Antibiotics,Aryl Alcohols, Respiratory Chain Inhibitors, Antifolates and Artemisinins
What are the 4 Aminoquniolones?
Amodiaquine, Piperaquine, Chloroquine,Pyronaridine. They work on asexual forms causing toxic waste to build up in the organism by binding to Chloroquine Resistance Transporter (CRT). Not active against Gametocytes
What are the 8 Aminoquinolones?
Primaquine and Tafedoquine. Primaquine acts on Gametocytes and Hypnozoites, not schizonts.. Tafedoquine acts on asexual forms and hypnozoites.
Side effects of 4 aminoquinolones?
Itch especially in Africans, GI and Psych sx.
Side effects of 8 Aminoquinolones?
Lysis and Methemoglobinemia with G6PD patients.
What are the Aryl Alcohols?
Quinine, Quinidine, Mefloquine, Halofantrine and Lumenfantrine. Unknown mechanism of action. USed in combination with abx or artemesinins.
What are the side effects of Aryl Alcohols?
Neuropsych problems, Hypoglycemia due to release of insulin, Hypotension, Avoid in 1st Trimester.
What Abx are used to treat Malaria?
Azithromycin, Clindamycin and Doxycycline, They inhibit protein synthesis. Active against heaptic and blood forms except hypnozoites. Used synergistically with artemisenins,and quinine.
What are the side effects of the Abx?
GI, Photosensitivity.Do not use in Pregnancy
What are the respiratory chain inhibitors?
Atovaquone. It acts on the parasite respiratory chain.It is used with Proguanil.
What is the combination of Atovaquone and Proguanil?
Malarone.Resistance develops rapidly to the Atovaquone. SIde effects are minimal.
What are the antifolate drugs?
Sulfadoxine(S), Pyrimethamine(P), Proguanil(P),Dapsone(D). They act on cofactors needed for nucleic acid synthesis.
How are the antifolates used? ? side effects?
As IP therapy 3 times during preganacy as Fansidar (Pyrimethamine and Sulfadoxine) DHPS (D and S)
, DHFR(P and P)
What are the Artemisenins?
Artesunate and Artemether. They produce toxic O2 radicals. Inactive against Hypnozoites. Short half life. Massive cleansing of parasites.Side effects are minimal, GI, fever, dizziness
How do you diagnose Malaria?
Thick Films, Thins Films and PCR
What is the treatment for uncomplicated Falciparum Malaria?
Coartem, Artesunate plus Amodiaquine, Artesunate plus Mefloquine, Artesunate plus SP, Dihydroartemesin plus Piperaquine (DHP), Malarone, Coartem (Artemether/Lumenfantrine), Quinine or Chloroquine
What is the treatment for Severe Falciparum Malaria?
IV quinine or IV quinidine plus Doxycycline or Clindamycin. In SE ASia Artesunate plus Doxy/Clinda,Mefloquine or Malarone. Exchage transfusion when parasitemia exceeds 15%.Start iron when patient is no longer malnourished.
What is the treatment for uncomplicated Vivax ?
Chloroquine plus Primaquine or if resistant to Chloroquine, Quinine plus Primaquine plus Doxycycline
What is the treatment for type unknown Malaria?
Same as for Severe falciparum.
What are the microscopic findings with P. Falciparum?
Lots of parasites with thin ring form trophozoities, applique forms, banana gametocytes and chromatin dots. Look for Maurer’s clefts.
What are the microscopic findings with P. Ovale/Vivax?
Look for infected large or oval shaped, ameboid RBC’s with 12 to 24 Merozoite Schizonts. Shuffner’s dots, ovoid gametocyte with brown pigmented granules.
What are the microscopic findings with P. Malariae?
Look for normal or small rbc’s with thick ring trophozoites, 10 merozites per schizont, birds eyes, baskets and Daisy Head forms
What medications are used for Malaria prophylaxis?
Chloroquine, Mefloquine, Primaquine, Malarone and Doxycycline.
What medications are used in Pregnancy?
SP(Fansidar),Mefloquine and Maloprim.
What is the WHO approach to prevention of Malaria?
Immunization (RTSS-Central Repeat Amino Acid Pattern, with T Cell Ag, Unfused HBV S Ag and AsO2 as an adjuvant. The imrmunization acts on the sporozoites CSP, Circumsporozoite Surface Protein, ITNs, IRS and ACT
What is the effect of Malaria in Pregnancy?
IUGR, LBWT, Stillbirth, Preterm Labor.Apregnant woman has twice the risk of being bitten by a mosquito. The altered ratio of Th1 to Th2 lymphocytes and altered interferon levels increase susceptibility.
How does a newborn present with Malaria?
Like a septic infant with jaundice, fever, anemia and hepatosplenomegaly
What are the standby regimens for Malaria?
Malarone250/100 4tabs in first 24 hrs then1x per day for 2 days; Coartem 20/1204 tabs x 6 doses; Mefloquine250 mg 3 tabs then 2 tabs 6 to 12 hours later.
How is Babesiosis transmitted?
Tick Bites from Lone Star or Ambyloma tick, transfusions and transplants.
What are the sx of Babesiosis?
Fever, HA, Myalgias, Fatigue and reduced appetite.
What are the lab findings associated with Babesiosis?
Maltese Crosses found in side and outside RBC’s, anemia and low platelets.
What are the complications of Babesiosis?
Cardiorespiratory and Renal Failure. Expect co-infection. Closely watch those who are asplenic and those who are immunocompromised.
What is the treatment of Babesiosis?
Clindamycin plus Quinine or Atovaquone plus Azithromycin