Nematodes Flashcards
what are the 3 nematode routes of infection?
- ingested
- cutaneous
- bites
species of nematodes that infect thru ingestion
- Enterobius
- Ascaris
- Toxocara
-
Trichinella
- “You’ll get sick if you EATT these!”
species of nematodes that infect cutaneously
- Stronglyloides
- Ancylostoma
-
Necator
- ”These get into your feet from the SANd”
species of nematodes that infect thru bites
- Loa loa
- Onchocerca volvulus
-
Wuchereria bancrofti
- “Lay LOW to avoid getting bitten”
explain the 2 types of immune responses to helminths
- eosinophils act by type I and type II hypersensitivity reactions in responding to helminths
- Type I
- neutralization of histamine and leukotrienes
- Type II
- eosinophils attach to surface of helminths via IgE and release cytokines (ie. major basic protein) contained in their granules
- Type I
name the 6 intestinal nematodes (roundworms)
- Enterobius vermicularis (pinworm)
- Ascaris lumbricoides (giant roundworm)
- Strongyloides stercoralis (threadworm)
- Ancylostoma duodenale, Necator americanus (hookworms)
- Trichinella spiralis
Enterobius vermicularis (pinworm)–disease
- intestinal infection causing anal pruritus
- diagnosed by seeing egg via the tape taste
Enterobius vermicularis (pinworm)–transmission
- fecal-oral
Enterobius vermicularis (pinworm)–treatment
- bendazoles (b/c worms are bendy)
Ascaris lumbricoides (giant roundworm)–disease
- intestinal infection with possible obstruction at ileocecal valve
Ascaris lumbricoides (giant roundworm)–transmission
- fecal-oral
- eggs visible in feces under microscope
Ascaris lumbricoides (giant roundworm)–treatment
- bendazoles
Strongyloides stercoralis (threadworm)–disease
- intestinal infection causing vomiting, diarrhea, epigastric pain (may mimic peptic ulcer)
Strongyloides stercoralis (threadworm)–transmission
- larvae in soil penetrate the skin
Strongyloides stercoralis (threadworm)–treatment
- ivermectin
- bendazoles
Ancylostoma duodenale, Necator americanus (hookworms)–disease
- intestinal infection causing anemia by sucking blood from intestinal wall
- Cutaneous larva migrans
- pruritic serpiginous rash from walking varefoot on contaminated beach
Ancylostoma duodenale, Necator americanus (hookworms)–transmission
- larvae penetrate skin
Ancylostoma duodenale, Necator americanus–treatment
- bendazoles
- pyrantel pamoate
Trichinella spiralis–disease
- intestinal infection
- larvae enter bloodstream and encyst in striated muscle cells –> inflammation of muscle
- Trichinosis
- fever
- vomiting
- nausea
- periorbital edema
- myalgia
Trichinella spiralis--transmission
- fecal-oral
- undercooked meat (especially pork)
Trichinella spiralis–treatment
- bendazoles
name the 4 tissue nematodes (roundworms)
- Toxocara canis
- Onchocerca volvulus
- Loa loa
- Wuchereria bancrofti
Toxocara canis–disease
- Visceral larva migrans
- nematodes migrate to blood thru intestinal wall causing inflammation and damage
- organs frequently affected include the heart (myocarditis), liver, and CNS (seizures and coma)
Toxocara canis–transmission
- fecal-oral
