Helminths Flashcards
Nematodes are what type of worm?
Round worm (filarial and non-segmented)
Cestodes are
Tapeworms (flat worms) - segmented
Trematodes are
Flukes (flat worms) - non-segmented
2 types of flat worms
Flukes (trematodes) and Cestodes
Segments in tapeworms are called
Proglottids
Clonorctis sinesis is a flatworm that causes
cholangiocarcinoma
Ascaris - causes
obstruction of small bowel
biliary colic
Flukes and tapeworms - lifecycle
Often dont have a sexually maturing stage they are hermaphrodites
Ascaris - life cycle
Direct life cycle
- fecal-oral
Ascaris and Filaria - mechanism of harming hosts
Mechanical obstruction -
- ascaris: biliary colic
- Filaria: Lymphatics
Which worm do you see macrocytic Vitamin B 12 deficiency?
Tapeworms -
Which worm do you often find out-competes the host for Iron?
Hookworm - lodges in bowel and removed blood from capillary
Fasciola liver fluke can cause
Cytotoxicity - to liver cells
Blood flukes like Schistosoma can cause
Granulomatous inflammation
schisotosoma species can cause malignant
Bladder cancer - metaplasia - squamous cell cancer
Which cell-mediated response is needed for clearance of intestinal worms?
Th2 response
Which cells are also important to fight worms coated with IgE
Eosinophils - degranulate onto IGE coated worms
Macrophages fight worms by
ROS intermediated after phagocytosing filaria
Nitric oxide produced in response to
IFN gamma and TNF-a
IgE dependent mast-cell reactions localize the
Eosinophils to parasites