Wk19 D1 Nematodes Flashcards
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.
(LO5)
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)
Whipworm
Which 3 nematodes autoinfect? Which causes life-threatening “hyperinfection” with HTLV-1 coinfection, steroid treatment or other
immunocompromise?
The 4 presentations of hyperinfection are:
(LO8)
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
Elephantiasis
Filaria obstruct lymphatics. spread via mosquito (day/night versions)
