Flashcards in Parasitic Infections Deck (75)
An organism living in or on a host and dependent on the host for nutrition – causing damage
What is the difference between an endoparasite and an ectoparasite?
Endoparasite – exist INSIDE the host
Ectoparasite – exist on the host
What are the two groups of endoparasites and what are the features of organisms within these two groups?
Eukaryotes (membrane bound nucleus)
Some have insect vectors
They are helminths/worms
Free living, intermediate hosts and vectors
Cause eosinophilia if they invade the blood
State the classes of organisms within the two groups of endoparasites.
Give some examples of amoeba.
Give some examples of coccidia.
Give an example of a ciliate.
Give some examples of flagellates.
What is the main difference between the two types of amoeba?
Entamoeba histolytica can cause invasive amoebiasis
Entamoeba dispar is a normal commensal of the GI tract
What is amoeba infection caused by?
Ingestion of mature cysts in food or water contaminated by faeces
Describe how E. histolytica infection causes disease.
The cysts enter the small intestine and release active amoebic particles (trophozoites), which invade the epithelial cells of the large intestines, causing flask-shaped ulcers
Infection can spread from the intestines to other organs e.g. liver, lungs and brain
Invasive amoebiasis may often cause amoebic liver abscesses
How many nuclei are there in mature cysts?
What are the treatment options for amoebiasis?
Nitroimidazole derivatives (kills trophozoites but not the cysts)
Parmomycine or Diloxanide Furoate
What are the five types of plasmodium that cause malaria?
What are the two types of host for plasmodium?
Female anopheles mosquito
What are the two stages of malaria in humans?
Describe the symptoms of malaria.
PAROXYSMAL (occurs every 4-8 hours)
State some complications of malaria.
Severe anaemia (due to intravascular haemolysis)
Abnormally low blood sugar
Swelling and rupturing of the spleen
What are the treatments for uncomplicated malaria?
Chloroquine (look at notes for the rest of the treatment options)
What is the treatment for severe malaria?
Artemisinin-based combination therapy
How is malaria diagnosed?
Blood film (+ Giemsa stain)
What are the routes of infection of toxoplasma gondii?
Eating undercooked meat of animals harbouring tissue cysts
Consuming food or water contaminated with cat faeces
Transplacentally from mother to foetus
Which group of patients are particularly vulnerable to toxoplasma infection?
What can toxoplasma infections cause in these individuals?
What does cryptosporidium cause?
DIARRHOEA (mainly in the immunocompromised)
How is it treated?
How are most diarrhoeal protozoal diseases diagnosed?
What are the reservoirs of balantidium coli?
What are the effects of balantidium coli infection in immunocompromised patients?