Flashcards in GI parasitic roundworms Deck (28):
What are the properties of nematodes?
1. Non-segmented bodies 2. Separate sexes 3. Complete digestive system
What are the properties of cestodes?
1. Segmented bodies 2. Hermaphroditic 3. Absorb nutrients
What are the properties of trematodes?
1. Non-segmented (leaf-shaped) 2. Hermaphroditic 3. Primitive gut
What is required to shed eggs in a nematode infection?
A male and a female nematode
Do adult nematodes replicate in the host?
What are the two groups of geohelminths?
1. Ascaris and trichuris - ingestion of infectious eggs 2. Strongyloides and hookworms - penetration of skin by infectious larvae in soil
What is the genus and species of pinworm?
What is the treatment for pinworms?
Mebendazole, pyrantel pamoate - single dose, repeated two weeks later
What is the genus and species of whipworm?
What are the symptoms of whipworm infection?
1. Heavy worm burden 2. Bloody, mucous containing diarrhea 3. Frequent stools 4. Rectal prolapse in children
What is the organism associated with ascariasis?
What are the characteristics of pulmonary disease associated with ascariasis?
1. Combination of physical presence of larvae and immune response to them 2. Mild cough, pneumonitis 3. Parasite antigens highly allergenic 4. Eosinophilia
What is the diagnosis for ascariasis?
1. Eggs in stool 2. Larvae or eosinophilia in sputum
What are the genus and species names of hookworm?
1. Necator americanus 2. Ancylostoma duodenale
What is the life cycle of hookworms?
1. Infective larvae penetrate skin from soil 2. Circulation - lungs - trachea - pharynx - swallowed 3. Adults attach to small intestine 4. Diagnostic stage - eggs in feces
What are the clinical manifestations of hookworm infection?
1. Iron-deficiency anemia due to blood loss from hookworm feeding 2. Moderate dermatitis at site of penetration 3. Pnuemonia and eosinophilia
What is the cause of strongyloidiasis?
What are the features of strongyloidiasis?
1. Facultative parasite - can be a free living nematode in soil 2. Larvae passed in stool 3. Worms produce eggs in soil, not intestines 4. Infectious larval form can develop in intestine, enter circulation, and re-initiate infection
What is the main cause of strongyloides hyperinfection and disseminated disease?
What is the diagnosis for strongyloidiasis?
Larvae in stool
Which nematode egg is flat on one side?
Enterobius vermicularis - pinworm
Which nematode egg is lemon / barrel shaped?
Trichuris trichiura - whipworm
Which nematode egg is lumpy / bumpy?
Which nematode egg is "boring / plain"?
Hookworm (necator americanus, ancylostoma duodenale)
Enterobius vermicularis (pinworm) has what kind of egg morphology?
Flat on one side
Trichuris trichiura (whipworm) has what kind of egg morphology?
Lemon / barrel shaped
Ascaris lumbricoides has what kind of egg morphology?
Lumpy / bumpy