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Flashcards in Wk19 D1 Nematodes Deck (16):

What is the DALY impact of nematodes? (LO1)

Associated with the impact of malnutrition.
Total: 39 M years
Hookworm: 22.1 M yr, 1 B people
Ascaris lumbricoides: 10.5 M yr, >20% of world pop
Trichuris Trichiura: 6.4 M yr

Mostly morbidity


What causes “river blindness?” (LO2)
Breeding location
Also causes ___ due to __ and __ forms

Onchocerca volvulus via black fly (vector)
Breeds rapidly in running water
Skin lesions, adult, microfilaria


Symptoms for (LO3)
Ascaris, Hookworm spp., Trichuris (whipworm), Stronglyoides, enterobius (pinworm), trichinosis,

Ascaris+Hookworm: Fever, Lungs, Eos, GI obs, Ascaris: pancreatitis, cholangitis, appendicitis, malnutrition, GROWTH+DEVELOPMENT
Hookworm: Anemia (species dependent), get in thru foot
Trichuris: Colon, rectal prolapse, anemia
Stronglyoides: GI, migrating skin larva, polymicrobial sepsis (immunocompromised)
Enterobius: Perianal, ernuresis, vaginitis
Trichinosis: GI, eyes


What is special about helminthic infections? (LO4)

Adults don't multiply in definitive hosts
Finite life spans
Damage proportional to worm burden
Eosinophilia when worms migrate thru tissue
Th2 controls the worms


What is the intestinal nematode that looks like a “white snake”? It's a __worm that resembles the common __. Shows as__ on US, __ on CT.

Ascaris. Round, earth worm.
Echogenic, non-shadowing
Cylindrical filling defects


What is its greatest impact? (LO6) (the "white snake") on global and individual scale

1.3 B affected
12 M acute illnesses
10 k deaths

Fever, Lungs, Eos, GI obs, pancreatitis, cholangitis, appendicitis, malnutrition


Which nematodes cause anemia? What is the major cause? (LO7)

Hookworms, depending on species, #, dietary Fe.
Ancylostoma duodenale
Necator americanus
Trichuris Trichiura aka whipworm (microcytc hypochromic, hyperchromic pernicious)


Which 3 nematodes autoinfect? Which causes life-threatening “hyperinfection” with HTLV-1 coinfection, steroid treatment or other
The 4 presentations of hyperinfection are:

Strongyloides stercoralis, Capillaria philippinensis, Hymenolepis nana.
Strongyloids causes chronic/hyper infections immuno-competent/compromised.

Polymicrobial sepsis,
Filariform larvae in GI, lung, CNS.
Dampening Th2 response is BAD, HTLV1->Th1 skew. Serology for diagnosis


Which nematode is nearest eradication? (LO9)
Name of disease. How do you get it? Why is it difficult to eradicate (life cycle-wise?)

Guinea worm diesease from dracunculus.
Drinking stagnant water contaminated with copepods (water fleas) with larvae. Creates open sore on skin which releases more larvae into water.


Miracle Drug

Albendazole (basically treats everything except Strongyloides)


Cutaneous larva migrans

if a dog/cat hookworm gets into you but you're not a dog or cat. can't complete life cycle, very itchy.


Worm with Th2 driving ability used to experimentally treat IBD.

Trichuris aka whipworm


Half the kindergarten has an itchy bottom

Pinworm, scotch tape test


Puffy eyes, feeling unwell

Trichinosis from trichinella



Filaria obstruct lymphatics. spread via mosquito (day/night versions)


Worm crawling in eye

loa loa from midge