MIcrobiology: Parasites Flashcards Preview

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Flashcards in MIcrobiology: Parasites Deck (69)
1

Bloating, flatulence, foul-smelling stools:

Giardia lamblia

2

Pear-shaped organism with tumbling motility:

Giardia lamblia

3

Treatment for Giardia infection:

Metronidazole

4

Organisms you treat with flagyl (6):

Flagyl = metronidazole
GET GAP for metro
Giardia
Entamoeba
Trichomonase
Gardnerella
Anaerobic bacteria
H. Pylori

5

Two nuclei in the trophozoite form, causes diarrhea in hikers:

Giardia

6

This protozoal infection causes liver abscesses:

Entamoeba histolytica

7

Blood diarrhea with RUQ pain:

Entamoeba histolytica
Remember that it causes liver abscess

8

Describe the colonic abscesses associated with Entamoeba infection

Flask-shaped ulcers with a wide base and narrow mouth

9

Treatment for Entamoeba infection (2 part):

Metronidazole kills amoebae
Iodoquinol kills the cysts

10

Is chlorine effective in preventing Cryptosporidium infection?

No.
Filtration only.

11

Cysts seen on acid-fast stain:

Cryptosporidium

12

In AIDS patients:
Cryptococcus: Diarrhea or meningitis?
Cryptosporidium: Diarrhea or meningitis?

Cryptosporidium -> diarrhea
Cryptococcus -> meningitis

13

Treatment for Cryptosporidium?

Trick question, there isn't one.
Prevention is the name of the game.

14

How do you diagnose Entamoeba infection (3):

Serology OR
Trophozoites containing RBCs in the blood OR
Multi-nucleated cysts in the stool

15

Trophozoites containing RBCs:

Entamoeba histolytica

16

Brain abscesses in HIV, ring-enhancing lesions:

Toxoplasma gondii

17

Classic triad for congenital toxo:

Chorioretinitis
Hydrocephalus
Intracranial calcifications

18

Treatment for Toxoplasmosis (2):

Sulfadiazine + pyrimethamine

19

This protozoan causes a rapidly fatal meningoencephalitis:
Where do you get it?
How is it diagnosed?

Naegleria fowleri
From freshwater lakes, up through cribiform plate
Spinal fluid has amoebae

20

Organism causing African sleeping sickness:

Trypanosoma brucei, gambiense, or rhodesiense

21

Treatment for African sleeping sickness:

"SUR is nice to take MELAtonin for sleep"
Suramin (for blood-borne disease)
Melarsoprol for CNS infection

22

Diagnosis of Toxoplasma (2):

Serology
Biopsy

23

Diagnosis of Trypanosoma infection:

Blood smear

24

This malaria species has a 48-hr fever cycle.
Malaria species with a 72-hr cycle?

Plasmodium vivax / ovale = 48hr
Plasmodium malariae = 72 hr cycle

25

This malarial form has no dormant liver form, whereas these two do:

P. falciparum = no dormant form.
P. malariae and vivax/ovale = have a dormant liver form

26

Banana-shaped gametocyte:

Plasmodium falciparum

27

RBC filled with merozoites:

Malaria

28

What is a hypnozoite?
How do you treat it?

Hypnozoite = resting liver form of malaria seen in vivax/ovale and malariae forms.
Tx is with primaquine

29

The ring form of this parasite can be confused with malaria, why?
How do you tell the two apart?

Babesia's ring form looks like the banana-shaped gametocyte of P. falciparum.
Babesia does not have hemazoin pigment deposits.

30

Maltese cross on blood smear:

Babesia

31

Treatment for babesiosis:

Atovaquone + azithromycin

32

Chagas' disease, three common findings:

Dilated cardiomyopathy
Megacolon
Magaesophagus (secondary achalasia)

33

Treatment for Chagas:

Nifurtimox

34

Macrophages containing amastigotes:
What is an amastigote?

Leishmania donovani
Amastigote = non-flagellated form of the organism

35

Ulcerating papules, transmitted by the sandfly:

Leishmania donovani

36

Spiking fevers, hepatosplenomegaly, pancytopenia:

Leishmania

37

Treatment for leishmaniasis:

Cutaneous = sodium stibogluconate
Systemic = liposomal amphotericin B

38

Pinworm:

Enterobius vermicularis

39

Giant roundworm:

Ascaris lumbricoides

40

Hookworm:

Ancylostoma, Necator

41

Most common helminth infection in the US:
In the world:

US = Enterobius = pinworm
World = Ascaris = giant roundworm

42

Treatment for Strongyloides infection:

Ivermectin, albendazole

43

These worms infect by penetrating skin:

SANd
Strongyloides
Ancylostoma
Necator
d

44

These worms are transmitted via fecal-oral route:

EAT
Enterobius
Ascaris
Trichinella

45

River blindness:
How is it transmitted?
Two features:

Onchocera
Female blackfly bite
Tx = ivermectin

46

Worm in conjunctiva:

Loa loa

47

Causes lymphatic filariasis:

Wuchereria

48

Huge hydrocele, transmitted by a female mosquito, how do you treat it?

This is elephantiasis caused by Wucheria, treat with diethylcarbamazine

49

Myositis and periorbital edema after eating undercooked bear:

Trichinella
Lives in muscles, dx by biopsy
From undercooked wild game or pork

50

New onset of neurologic symptoms in a young immigrant:

Taenia solium, think neurocysticercosis

51

Treatment for neurocysticercosis:

Praziquantel +
Bendazoles

52

How is Taenia solium transmitted to people?

Ingestion of undercooked pork (larvae)
Ingestion of eggs (fecal-oral)

53

Came from dog feces, hyadatid cysts in liver:

Echinococcus

54

Leak of liver cyst contents caused anaphylaxis:

Echinococcus

55

Ate a raw freshwater fish and got vitamin B12 deficiency:

Diphyllobothrium

56

Blood fluke:

Schistosoma

57

Snail host:

Schistosoma

58

Undercooked fish, causes pigmented gallstones:

Clonorchis

59

Brain cysts, seizures:

Taenia (tapeworm)

60

Liver cysts:

Echinococcus (tapeworm)

61

Vitamin B12 deficiency:

Diphyllobothrium (tapeworm)

62

Biliary tract disease and cholangiocarcinoma:

Clonorchis (fluke)

63

Hemoptysis, crab meat:

Paragonimus (the "lung" fluke)

64

Portal HTN:

Schistosoma mansoni (blood fluke)

65

Hematuria and bladder cancer:

Schistosoma haematobium (a blood fluke)

66

Microcytic anemia:

Ancylostoma &
Necator, both roundworms
Both suck blood from intestinal walls

67

Perianal pruritis:

Enterobius

68

What happens if you drink alcohol while on flagyl?

Disulfarim-like reaction, feel awful

69

Anaerobic infections below the diaphragm you treat with:
Above the diaphragm you treat with:

Below = metronidazole
Above = clindamycin