MIcrobiology: Parasites

Question 1

Bloating, flatulence, foul-smelling stools:

Answer 1

Giardia lamblia

Question 2

Pear-shaped organism with tumbling motility:

Answer 2

Giardia lamblia

Question 3

Treatment for Giardia infection:

Answer 3

Metronidazole

Question 4

Organisms you treat with flagyl (6):

Answer 4

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

Question 5

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

Answer 5

Giardia

Question 6

This protozoal infection causes liver abscesses:

Answer 6

Entamoeba histolytica

Question 7

Blood diarrhea with RUQ pain:

Answer 7

Entamoeba histolytica

Remember that it causes liver abscess

Question 8

Describe the colonic abscesses associated with Entamoeba infection

Answer 8

Flask-shaped ulcers with a wide base and narrow mouth

Question 9

Treatment for Entamoeba infection (2 part):

Answer 9

Metronidazole kills amoebae

Iodoquinol kills the cysts

Question 10

Is chlorine effective in preventing Cryptosporidium infection?

Answer 10

No.

Filtration only.

Question 11

Cysts seen on acid-fast stain:

Answer 11

Cryptosporidium

Question 12

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

Answer 12

Cryptosporidium -> diarrhea

Cryptococcus -> meningitis

Question 13

Treatment for Cryptosporidium?

Answer 13

Trick question, there isn’t one.

Prevention is the name of the game.

Question 14

How do you diagnose Entamoeba infection (3):

Answer 14

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

Question 15

Trophozoites containing RBCs:

Answer 15

Entamoeba histolytica

Question 16

Brain abscesses in HIV, ring-enhancing lesions:

Answer 16

Toxoplasma gondii

Question 17

Classic triad for congenital toxo:

Answer 17

Chorioretinitis
Hydrocephalus
Intracranial calcifications

Question 18

Treatment for Toxoplasmosis (2):

Answer 18

Sulfadiazine + pyrimethamine

Question 19

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

Answer 19

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

Question 20

Organism causing African sleeping sickness:

Answer 20

Trypanosoma brucei, gambiense, or rhodesiense

Question 21

Treatment for African sleeping sickness:

Answer 21

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

Question 22

Diagnosis of Toxoplasma (2):

Answer 22

Serology

Biopsy

Question 23

Diagnosis of Trypanosoma infection:

Answer 23

Blood smear

Question 24

This malaria species has a 48-hr fever cycle.

Malaria species with a 72-hr cycle?

Answer 24

Plasmodium vivax / ovale = 48hr

Plasmodium malariae = 72 hr cycle

Question 25

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

Answer 25

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

Question 26

Banana-shaped gametocyte:

Answer 26

Plasmodium falciparum

Question 27

RBC filled with merozoites:

Answer 27

Malaria

Question 28

What is a hypnozoite? | How do you treat it?

Answer 28

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

Question 29

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

Answer 29

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

Question 30

Maltese cross on blood smear:

Answer 30

Babesia

Question 31

Treatment for babesiosis:

Answer 31

Atovaquone + azithromycin

Question 32

Chagas' disease, three common findings:

Answer 32

Dilated cardiomyopathy Megacolon Magaesophagus (secondary achalasia)

Question 33

Treatment for Chagas:

Answer 33

Nifurtimox

Question 34

Macrophages containing amastigotes: | What is an amastigote?

Answer 34

Leishmania donovani | Amastigote = non-flagellated form of the organism

Question 35

Ulcerating papules, transmitted by the sandfly:

Answer 35

Leishmania donovani

Question 36

Spiking fevers, hepatosplenomegaly, pancytopenia:

Answer 36

Leishmania

Question 37

Treatment for leishmaniasis:

Answer 37

``` Cutaneous = sodium stibogluconate Systemic = liposomal amphotericin B ```

Question 38

Pinworm:

Answer 38

Enterobius vermicularis

Question 39

Giant roundworm:

Answer 39

Ascaris lumbricoides

Question 40

Hookworm:

Answer 40

Ancylostoma, Necator

Question 41

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

Answer 41

``` US = Enterobius = pinworm World = Ascaris = giant roundworm ```

Question 42

Treatment for Strongyloides infection:

Answer 42

Ivermectin, albendazole

Question 43

These worms infect by penetrating skin:

Answer 43

``` SANd Strongyloides Ancylostoma Necator d ```

Question 44

These worms are transmitted via fecal-oral route:

Answer 44

EAT Enterobius Ascaris Trichinella

Question 45

River blindness: How is it transmitted? Two features:

Answer 45

Onchocera Female blackfly bite Tx = ivermectin

Question 46

Worm in conjunctiva:

Answer 46

Loa loa

Question 47

Causes lymphatic filariasis:

Answer 47

Wuchereria

Question 48

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

Answer 48

This is elephantiasis caused by Wucheria, treat with diethylcarbamazine

Question 49

Myositis and periorbital edema after eating undercooked bear:

Answer 49

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

Question 50

New onset of neurologic symptoms in a young immigrant:

Answer 50

Taenia solium, think neurocysticercosis

Question 51

Treatment for neurocysticercosis:

Answer 51

Praziquantel + | Bendazoles

Question 52

How is Taenia solium transmitted to people?

Answer 52

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

Question 53

Came from dog feces, hyadatid cysts in liver:

Answer 53

Echinococcus

Question 54

Leak of liver cyst contents caused anaphylaxis:

Answer 54

Echinococcus

Question 55

Ate a raw freshwater fish and got vitamin B12 deficiency:

Answer 55

Diphyllobothrium

Question 56

Blood fluke:

Answer 56

Schistosoma

Question 57

Snail host:

Answer 57

Schistosoma

Question 58

Undercooked fish, causes pigmented gallstones:

Answer 58

Clonorchis

Question 59

Brain cysts, seizures:

Answer 59

Taenia (tapeworm)

Question 60

Liver cysts:

Answer 60

Echinococcus (tapeworm)

Question 61

Vitamin B12 deficiency:

Answer 61

Diphyllobothrium (tapeworm)

Question 62

Biliary tract disease and cholangiocarcinoma:

Answer 62

Clonorchis (fluke)

Question 63

Hemoptysis, crab meat:

Answer 63

Paragonimus (the "lung" fluke)

Question 64

Portal HTN:

Answer 64

Schistosoma mansoni (blood fluke)

Question 65

Hematuria and bladder cancer:

Answer 65

Schistosoma haematobium (a blood fluke)

Question 66

Microcytic anemia:

Answer 66

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

Question 67

Perianal pruritis:

Answer 67

Enterobius

Question 68

What happens if you drink alcohol while on flagyl?

Answer 68

Disulfarim-like reaction, feel awful

Question 69

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

Answer 69

``` Below = metronidazole Above = clindamycin ```