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Y2 Micro (MCD) > Parasitic Infections > Flashcards

Flashcards in Parasitic Infections Deck (79)
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1

Define parasite.

An organism living in or on a host and dependent on the host for nutrition – causing damage

2

What is the difference between an endoparasite and an ectoparasite?

Endoparasite – exist INSIDE the host Ectoparasite – exist on the host

3

What are the two groups of endoparasites?

Protozoa Metazoa

4

State the classes of organisms within the two groups of endoparasites.

Protozoa

  •  Amoeba
  •  Coccidia
  •  Ciliates
  •  Flagellates

Metazoa

  •  Roundworms
  •  Flatworms
  •  Flukes

5

Give some examples of amoeba.

Entamoeba histolytica Entamoeba dispa

6

Give some examples of coccidia.

  • Plasmodium species
  • Toxoplasma
  • Cryptosporidium

7

Give an example of a ciliate.

Balantidium coli

8

Give some examples of flagellates.

  • Trypanosoma
  • Trichomonas
  • Giardia
  • Leishmania

9

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

10

What is amoeba infection caused by?

Ingestion of mature cysts in food or water contaminated by faeces

11

Describe how E. histolytica infection causes disease.

  • The cysts enter the small intestine and release active amoebic particles (trophozoites)
  • These invade the epithelial cells of the large intestines
  • This causes flask-shaped ulcers
  • Infection can spread from the intestines to other organs
  • Invasive amoebiasis may often cause amoebic liver abscesses

12

How many nuclei are there in mature cysts?

4

13

What are the treatment options for amoebiasis?

Nitroimidazole derivatives (kills trophozoites but not the cysts) Parmomycine or Diloxanide Furoate

14

What are the five types of plasmodium that cause malaria?

Falciparum Malariae Vivax Ovale Knowlesi

15

What are the two types of host for plasmodium?

  • Human
  • Female anopheles mosquito

16

What are the two stages of malaria in humans?

Liver Blood

17

Describe the symptoms of malaria.

PAROXYSMAL (occurs every 4-8 hours) Fever Chills Headaches Vomiting Muscle pain

18

State some complications of malaria.

  • Severe anaemia (due to intravascular haemolysis)
  • Cerebral malaria
  • Liver failure
  • Shock
  • Pulmonary oedema
  • Abnormally low blood sugar
  • Kidney failure
  • Swelling and rupturing of the spleen

19

What are the treatments for uncomplicated malaria?

Chloroquine

20

What is the treatment for severe malaria?

Artemisinin-based combination therapy

21

How is malaria diagnosed?

Blood film (+ Giemsa stain)

22

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 Blood transfusion Organ transplantation Transplacentally from mother to foetus

23

Which group of patients are particularly vulnerable to toxoplasma infection?

Immunocompromised and in pregnancy - the fetus

24

What can toxoplasma infections cause in immunocomprimised individuals?

CNS disease Brain lesions Pneumonitis Retinochoroiditis

25

What does cryptosporidium cause?

DIARRHOEA (mainly in the immunocompromised)

26

How is it treated?

Fluid rehydration

27

How are most diarrhoeal protozoal diseases diagnosed?

Stool examination

28

What are the reservoirs of balantidium coli?

Primates Rodents Pigs

29

What are the effects of balantidium coli infection in immunocompromised patients?

Persistent DIARRHOEA Dysentery Abdominal pain Vomiting Nausea Note: If left untreated can cause perforation of the colon

30

How can drinking water be cleared of ovoid giardia lamblia cysts?

Filtration Ovoid cysts can survive standard chlorination procedures