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Flashcards in Micro Parasites Deck (40)
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1
Q
Giardia lamblia 
What kind of organism?
What does it cause? Presentation?
Who gets it?
Transmission 
Diagnosis 
Treatment
A
Anaerobic parasitic protozoan
Giardiasis: bloating flatulence, foul-smelling, fatty diarrhea 
Campers/Hikers 
Cysts in water 
Trophozoite or cyst in stool 
Metronidazole
2
Q
Entamoeba histolytica 
What kind of organism?
What does it cause? Presentation?
Histo
Transmission 
Diagnosis 
Treatment
A

Anaerobic parasitic protozoan
Amebiasis: bloody diarrhea, Liver abscess (anchovy paste exudate), RUQ pain
Flask-shaped ulcer if submucosal abscess of colon ruptures
Cysts in water
Serology +/or trophozoites (w/ RBCs in cyto) or cysts (w/ multiple nuclei) in stool
Metronidazole. Iodoquinol for asymptomatic cyst passers

3
Q
Cryptosporidium
What kind of organism?
Who gets it?
Presentation 
Transmission 
Diagnosis 
Treatment
A

Parasitic protozoan
AIDS pts
Severe diarrhea. Watery diarrhea in non-immunocompromised
Cysts in water
Cysts on acid fast stain
Prevention (filtering water). Nitazoxanide in immunocompetent hosts

4
Q
Toxoplasma gondii
What is it?
What kind of pt gets them?
What do they cause?
Imaging?
Transmission 
Diagnosis 
Treatment
A

Obligate, intracellular, parasitic protozoan
HIV pts
Brain abscess. Seen as ring-enhancing brain lesions on CT/MRI
Congenital toxoplasmosis = classic triad of Chorioretinitis (eye), Hydrocephalus, Intracranial calcification
Cysts in meat or oocysts in cat feces (crosses placenta)
Serology, Biopsy
Sulfadiazine, Pyrimethamine

5
Q
Naegleria fowleri 
What is it?
What does it cause?
Transmission 
Diagnosis 
Treatment
A

Protists parasite
Rapidly fatal meningeoencephalitis
Swimming in freshwater lakes. Enters via cribiform plate
“Nalgene bottle filled with freshwater containing Naegleria”
Amoebas in spinal fluid
Amphotericin

6
Q
Trypanosoma brucei 
Sub species?
What kind of organisms is it?
What does it cause?
Presentation 
Transmission 
Diagnosis 
Treatment
A

T. gambiense and T. rhodesiense
Protozoan
Africa sleeping sickness
Enlarged lymph nodes, recurring fever (antigenic variation), Somnolence, Coma
Tsetse fly (a painful bite)
Blood smear
Suramin for blood borne disease. Melarsoprol for CNS penetration

7
Q
Plasmodium
Species? What kind of organism?
What do they cause? Presentation?
Transmission 
Diagnosis 
Treatment
A

P vivax/ovale, P falciparum, P. malariae
Protists
Malaria: fever, headache, anemia, splenomegaly
Mosquito (Anopheles)
Blood smear, Trophozoite ring form, RBC schizont with merozoites
Begin w/ Chloroquine (blocks plasmodium heme polymerase). If resistent use Mefloquine. If life threatening use IV quinidine and test for G6PD deficiency

8
Q

Plasmodium vivax/ovale
Presentation
Treatment

A
48 hour cycle (fever on 1st and 3rd day - tertian)
Dormant form (hypnozoite) in liver 
Add primaquine for hypnozoite and test for G6PD deficiency)
9
Q

Plasmodium falcipartum
Presentation
Histo

A

Severe, irregular fever pattern.
Parasitized RBCs occlude capillaries in brain (cerebral malaria), Kidney, and Lungs
Banana shaped

10
Q

Plasmodium malariae presentation

A

72 hour cycle (quartan)

11
Q
Babesia 
What kind of organism?
What does it cause? Presentation?
Location?
Risk?
Transmission 
Diagnosis 
Treatment
A
Protozoan parasite
Babesiosis: fever and hemolytic anemia 
NE USA
Asplenia --> risk of severe disease
Ixodes tick (same as Lyme disease)
Blood smear, ring form, "Maltese cross," PCR
Atovaquone + Azithromycin
12
Q
Trypanosoma cruzi 
What kind of organism?
What do they cause? Presentation?
Location 
Transmission 
Diagnosis 
Treatment
A
Protozoan parasite 
Chagas' Disease: Dialted cardiomyopathy, Megacolon, Megaesophagus
South America 
Reduviib bug (painless bite)
Blood smear 
Nifurtimox
13
Q
Leishmania donovani 
What kind of organism?
What does it cause? presentation?
Transmission 
Diagnosis 
Treatment
A
Protozoa
Visceral Leishmaniasis: Spiking fever, HSM, Pancytopenia 
Sandfly 
Macrophages containing amastigotes 
Sodium Stibogluconate
14
Q
Trichomonas vaginalis 
What kind of organism
What does it cause? Presentation 
Transmission 
Diagnosis 
Treatment
A

Anaerobic flagellated protozoan
Vaginitis: Foul smelling greenish discharge, itching and burning
Sexual (does not form cysts)
Trophozoites on wet mount
Metronidazole for pt and partners (prophylaxis)

15
Q
Enterobius vermicularis
What kind of organism?
Name
Transmission 
Disease 
Diagnosis 
Treatment
A
Nematode (roundworm). Pinworm 
Contaminated eggs 
Intestinal infection causing anal pruritus 
Scotch tape test 
Bendazoles or Pyrantel Pamoate 
"worms are BENDy, treat with meBENDzole"
16
Q
Ascaris lumbricoides 
What kind of organism?
Name
Transmission 
Disease 
Diagnosis 
Treatment
A
Nematode (roundworm). Giant Roundworm 
Fecal-to-oral
Intestinal infection 
Eggs visible in feces under microscope 
Bendazoles or Pyrantel Pamoate
17
Q
Strongyloides stercoralis 
What kind of organism?
Transmission 
Disease  
Treatment
A

Nematode (roundworm)
Larvae in soil penetrate skin
Intestinal infection causing vomiting, diarrhea, anemia
Ivermectin or Albenazole

18
Q
Ancylostoma duodenale, Necator americanus  
What kind of organism? Name?
Transmission 
Disease  
Treatment
A

Nematode (roundworm). Hookworm
Larvae penetrate skin
Intestinal infection causing anemia by sucking blood from intestinal walls
Bendazoles or Pyrantel Pamoate

19
Q
Dracunculus medinensis 
What kind of organism?
Transmission 
Disease  
Treatment
A

Nematode (roundworm)
Drinking water
Skin inflammation and ulceration
Slow extraction of worms

20
Q
Onchocerca volvulus 
What kind of organism?
Transmission 
Disease  
Mechanism
Treatment
A

Nematode (roundworm)
Female blackfly bite
Hyperpigmentated skin and river blindness
“Black flies, Black skin nodules, Block sight”
Allergic reaction to microfilaria posible
Ivermectin
“IVERmectin for rIVER blindness”

21
Q
Loa Loa 
What kind of organism?
Transmission 
Disease  
Treatment
A

Nematode (roundworm)
Deer, horse, or mango flies
Swelling in skin, worms in conjunctiva
Diethylcarbamazine

22
Q
Wuchereria bancrofti 
What kind of organism?
Transmission 
Disease  
Treatment
A

Nematode (roundworm)
Female mosquito
Blocks lymphatic vessels –> elephantiasis ~1 year after bite
Diethylcarbamazine

23
Q
Toxacara canis 
What kind of organism?
Transmission 
Disease  
Treatment
A

Nematode (roundworm)
Eggs
Visceral larva migrans
Albendazole or mebendazole

24
Q

Nematodes Routes of Infection

A

“get sick if EAT these”
Enterobius, Ascaris, Trichinella
“Get these in your feet from SANd”
Strongyloides, Ancylostoma, Necator

25
Q
Taenia solium 
What kind of organism?
Transmission 
Disease 
Treatment
A

Cestodes (tapeworm)
Larvae or eggs ingested in undercooked pork
Larvae: Intestinal infection, Praziquantel
Egg: Cysticercosis, Neurocysticercosis
Goes to Brain, Muscles, Heart, and Skin
Praziquantel, -bendazoles for neurocysticercosis

26
Q
Diphyllobothrium latum 
What kind of organism?
Transmission 
Disease 
Treatment
A

Cestodes (tapeworm)
Ingestion of larvae from raw freshwater fish
VitB12 deficiency –> anemia
Praziquantel

27
Q
Echinococcus granulosus 
What kind of organism?
Transmission 
Disease 
Treatment
A

Cestodes (tapeworm)
Ingestion of eggs from dog feces
Cysts in liver. Anaphylaxis of Ags released (surgeon’s preinject with EtOH to kill cysts before removal
-bendazoles

28
Q
Schistosoma 
What kind of organism?
Host
Transmission 
Disease 
Treatment
A

Trematodes (flukes)
Snails
Cercariae (larva) penetrate skin
Liver and spleen granulomas, fibrosis and inflammation
Chronic infection with S haematobium can lead to squamous cell carcinoma of the bladder d
Praziquantel

29
Q
Clonorchis sinensis 
What kind of organism?
Transmission 
Disease 
Associated with?
Treatment
A
Trematodes (flukes)
Undercooked fish
Biliary tract inflammation --> pigmented gallstones 
Cholangiocarcinoma 
Praziquantel
30
Q
Paragonimus westermani 
What kind of organism?
Transmission 
Disease 
Associated with?
Treatment
A

Trematodes (flukes)
Undercooked crab meat
Lung inflammation and secondary bacterial infection with hemoptysis
Praziquantel

31
Q

Brain cysts, Seizures

A

Taenia solium (Cysticercosis)

32
Q

Liver cysts

A

Echinococcus granulosus

33
Q

VitB12 deficiency?

A

Diphyllobothrium latum

34
Q

Biliary tract disease, Cholangiocarcinoma

A

Clonorchis sinensis

35
Q

Hemoptysis

A

Paragonimus westermani

36
Q

Portal HTN

A

Schistosoma mansoni

37
Q

Hematuria, Bladder Cancer

A

Schistosoma haematobium

38
Q

Microcytic Anemia

A

Ancylostoma duodenale, Necator americanus

39
Q

Perianal pruritus

A

Enterobius

40
Q

Helminths

A

Cestodes, Trematodes, Nematodes