Parasites in the Circulation Flashcards
What is the insect vector for african Trypanosomiasis?
Tsetse flies
What is the insect vector for Chagas’ disease?
Reduvid bugs
What is the insect vector for Lesihmaniosis?
Sandflies
What is the insect vector for Malaria?
Mosquitoes
What is the insect vector for Babesiosis?
Ticks
What is the only disease discussed that is not an intracellular parasite?
African trypanosomiasis
What is the causative agent of sleeping sickness?
Trypanosoma brucei
Where is Trypanosoma Brucei found in the world?
Africa
What is the life cycle of Trypanosoma brucei?
Tsetse fly picks up protozoa from host, bites another
What are the early signs/symptoms of Trypanosoma brucei infection? (3)
Painless indurated area where the fly bit
Cervical lymphadenopathy
Wasting appearance
What is the transmission for Trypanosoma brucei gambiense? (west african)
Human to human spread
What is the transmission for Trypanosoma brucei rhodesiense? (east african)
Human to human or animal to muman
What are the late stage symptoms of sleeping sickness?
HA, Szs, tremors, encephalitis, sleeplessness, lethargy
How do you diagnose sleeping sickness?
Detection of parasites in blood or CSF
What is the pattern of infection for sleeping sickness? What causes this?
Variable numbers of protozoa, d/t antibody destruction, then antigenic variation
How does Trypanosoma brucei avoid immune destruction, and remain in the body for months/years?
Rapid antigenic variation
What is the treatment for Trypanosoma brucei? (2) Side effects?
Melarsoprol or DFMO
Encephalitis/death
What is the causative agent of Chagas Disease?
Trypanosoma Cruzi
What is the life cycle of Trypanosoma Cruzi?
Reduviid bug to intracellular parasite
What are the initial symptoms of Trypanosoma Cruzi infections (Chagas disease)?
Chagoma
Fever/nonspecific
Local swelling
Periorbital edema
What are the later symptoms of Trypanosoma Cruzi (chagas disease)?
Dysrhythmias
Cardiomyopathy
Megacolon
Megaesophagus
Where are the parasites that come out of the Reduviid bugs for Trypanosoma Cruzi?
In the poop (NOT in the suckers)
Where are infections with Trypanosoma Cruzi (Chagas disease) found in the world usually?
South America
How long do late symptoms of Chagas disease take to present?
Decades
Do we screen blood for Trypanosoma Cruzi?
Yes
What is the chagoma sign? What disease is it seen in?
Indurated, erythematous area on the skin where the Reduviid bug bite
Chagas disease (Trypanosoma Cruzi infx)
Asymptomatic individuals infected with Trypanosoma Cruzi (chagas disease) harbor parasites where?
Autonomic ganglia
Heart tissue
How do you diagnose Trypanosoma Cruzi (Chagas disease)?
Serology
What are the important history facts about Chagas disease or sleeping sickness?
Recent travel
What is the causative agent of Leishmaniasis?
Leishmania
What is the lift cycle for Leishmania?
Sandflies transfer the parasite
What happens when Leishmania gets injected into tissues?
Ingested into macrophages, but this is nice for it.
Where do Leishmania parasites hide?
Macrophages
Who is particularly susceptible to Leishmaniasis?
HIV pts
How is Leishmania transmitted?
Sand flies or canines
What are the three clinical presentations of Leishmaniasis?
Cutaneous
Mucocutaneous
Visceral
What are the early symptoms of visceral Leishmaniasis?
Fevers
What are the late symptoms of visceral Leishmaniasis?
Fever
Weight loss
Hepatosplenomegaly
Immune suppression
What is the treatment for Leishmaniasis?
Metal compounds that are horrible
Why aren’t antibodies effective for destroying Leishmania? What is the only defense the body has that is effective?
Leishmania live in macrophages so protected.
T-cells needed or activation of macrophages
What is the most important of all tropical and parasitic diseases?
Malaria
Where in the world is Malaria found?
Everywhere
Who gets diagnosed with Malaria in the US?
Travelers, military personnel
What is the causative agent of Malaria (4)?
Plasmodium Falciparum (lesser = vivax, malariae, ovale)
What is the life cycle of Plasmodium falciparum (Malaria)?
Mosquitoes hold plasmodium, where they have sex. Parasites injected, rapidly cleared by liver
What happens to the plasmodium when they are infected into the body?
Infect hepatocyte for a while, then infect RBCs
What are the two species of plasmodium that cause Malaria can live in hepatocytes for years/decades?
P. Vivax
P. Ovale
Why is anemia associated with Malaria?
Bursting out of parasites from RBCs
What is Malarial paroxysm?
Severe flu-like symptoms that occur when a bunch of plasmodium leave hepatocytes/RBCs
What are the timing of symptoms (fever) of each of the Plasmodium species? (vivax/ovale, malariae, falciparum)
P Vivax/ovale = 48 hours
P. Malariae = 72 hours
P. Falciparum ~48 hours
What are the three mechanisms of pathogenesis of Malaria?
- RBC lysis
- Supression of erythropoiesis
- Destruction of RBCs by spleen
What is the effect of TNF-alpha and IL-1 (released when Plasmodium infects) on erythropoiesis?
Supression
Why are RBCs destroyed by the spleen in Malaria?
Coating of antigen
Which type of RBCs do P. Falciparum infect?
Any
Which type of RBCs do P. vivax and ovale infect?
Reticulocytes
Which type of RBCs do P. malariae infect?
older erythrocytes
What are the later symptoms of Malaria? (3)
Splenomegaly
Hypoglycemia
Lactic acidosis
Why is hypoglycemia and lactic acidosis seen in malaria?
Glucose utilization by Plasmodium
What is the pathogenesis of cerebral malaria?
Sticky knobs on infected RBCs form clots and make it harder to perfuse organs (like the brain)
How do you diagnose malaria? (3, two clinical + one test)
Travel history
Spiking fevers
Blood smear/antigen tests
Why is a blood smear the gold standard for malaria diagnosis?
Get parasite levels too
What do the gametocytes of plasmodium falcifera look like histologically?
Purple bananas
How do you prevent malarial disease?
Prophylaxis before travel
What is the causative agent of Babesiosis?
Babesia
What is the life cycle of Babesia?
tick bites and rodents
What are the initial symptoms of Babesiosis
Fever, chills, myalgias
Hemolytic
Who are particularly susceptible to Babesiosis?
Asplenic individuals
What is a maltese cross?
Babesia
What is the treatment for Babesiosis?
Azithromycin
What is the causative agent of filariasis?
Wuchereria bancrofti
Brugia malayi
What are the symptoms of filariasis?
Severe lymphadenopathy d/t clogging
What is the life cycle of filariasis?
Mosquito bites, migrate to lymph nodes
How long does filariasis take to develop? Why?
A year for helminth to travel to the lymph nodes and lay eggs
What are the initial symptoms of filariasis?
Non-specific, lymphadenitis
What is the treatment for filariasis?
Steroids/ surgery
What is the cause of schistosomiasis?
Schistosoma
How are Schistosoma transmitted?
Feces, Snails, penetrate skin to GI
What are the three species of Schistosoma? Where are they found in the body?
S. Mansoni - large intestines
S. Japonicum - small intestines
S. Haematobium - bladder
What are the consequences of Schistosomasis?
Chronic infections for lodging of eggs in tissue
How do you diagnose Schistosomiasis?
eggs in stool
What are the symptoms of S. Japonci
Chronic intestinal and hepatic dysfunction
What are the species of Leishmania that cause visceral disease?
L. Donovani
L. Infantum
L. Chagasi
How do you diagnose Filariasis?
Observe microfilariae in the blood