Intestinal Nematodes Flashcards
Hookworm infection
Filariform larvae in soil penetrate SKIN of feet (ground itch)
Warm moist climates
Ancylostoma duodenale
Necator americanus
Ancylostoma
Necator
Definitive host
Human
Ancylostoma
Necator
Infective stage
Filariform larvae
Ancylostoma
Necator
Hookworm diagnostic stage
Eggs in feces
Ancylostoma
Necator
Penetrate skin of soles and feet
Blood stream -> lungs -> GI tract
can cause
IDA from blood loss of GIT attachment of worm
Ancylostoma
Necator
Tx
Albendazole
Mebendazole
Pyrantel pamoate
Food with soil containing eggs
Cosmopolitan
Well tolerated unless infection is heavy or host is undernourished
Ascariasis
Largest of intestinal nematode
Eating egg contaminated food
Larvae hatch and attach in the small instestine
Blood stream -> lungs -> alveoli -> GIT
Ascariasis
Giant worm larvae ascaris infecting the lung
Worst complication of ascaris
Loeffler’s pneumonia
Intestinal obstruction at ileocecal valve
Ascaris infective stage
Larva
Ascaris diagnostic stage
Fertilized egg
Unfertilized egg
Major damage occurs during migration of work rather than presence of the worm in the intestine
Most infection are asymptomatic
Larvae in lung can cause pneumonia
Heavy worm infestation can cause anemia and intestinal obstruction or malnutrition
Ascaris lumbricoides
Ascaris tx
Mebendazole
Pyrantel pamoate
Ivermectin (filariasis)
Human seatworm
Pinworm
Ingest eggs by autoinfection, inhalation or swallowing from beddings, carpet
Humans only host
Enteobius vermicularis
Gravid female migrates to perianal skin to deposite embryonated eggs
Cardinal manifestation: nocturnal pruritus
Enterobius vermicularis
Enterobius
Dx
Scotch tape/Graham Cellphone test
Enterobius Infective state
Embryonated eggs
Enterobius diagnostic stage
Eggs
Children younger <12 old
Most common in US
Enterobius vermicularis
Enterobius Tx
Mebendazole
Pyrantel pamoate
Raw or undercooked meat, pork
Reservoir host - pigs, rats
Intestinal nematode that encyst in tissue (striated muscle)
Muscle pain
Periorbital edema
Diarrhea
Trichinella spiralis
Trichinella larvae invades
Skeletal muscle
Trichinella can cause
Heart failure
CNS
Trichinella Diagnostic test
Encysted larva in muscle with poor glycogen
Muscle biopsy
Bachman intradermal test
Bentonite Flocculation test
Trichinella spiralis Tx
Thiabendazole
Whipworm
Food and water contaminated with soil
Humans only host
Tropics
Trichuris trichuris
Final habitat of trichuris
Cecum
Ascending colon
Abdominal pain
Bloody diarrhea
Anemia
Rectal prolapse
Trichuris trichuria
Rectal prolapse
Diagnosis via DFS
Bipolar mucus plugs
Japanese lantern/football shaped appearance of ova
Trichuris trichuria
Causes hypochromic anemia
Trichuris trichuria
Trichuris Dx
Egg in feces
Trichuris trichuria tx
Mebendazole
Trichuris trichuria infective stage
Embryonated egg
Trichuris trichiuria infective stage
Unembryonated egg
Threadworm
Filariform larvae in soil penetrate skin
Warm climate
Autoinfection
Strongyloides stercoralis
Little effect
Massive superinfection with secondary bacterial infection in immunocompromised
Cause hyperinfection and dissemination of worms
Stronglyoides
Strongyloides Dx
Larvae in stool
Not eggs because they get laid in the intestinal wall
Strongyloides tx
Thiabendazole
Strongyloides Dx
Stool Filter paper culture method
Harada mori
Endemic in Philippines (Ilocos norte)
Man only host - internal autoinfection
Ingestion of raw or undercooked infected fish (kinilaw)
Human intestinal capillariasis
Capillaria philippinensis
Capillariasis is associated with
Protein losing enteropathy
Cardiomyopathy
Severe emaciation
Cachexia
Ingestion through contaminated fish
Abdominal pain
Diarrhea
Borborygmus
Capillaria philippinensis
Capillaria egg on microscopy
Peanut shell appearance
Capillaria tx
Mebendazole
Albendazole
Capillaria infective stage
Larvae
Capilaria diagnostic stage
Unembryonated egg
Capillaria is associated with
Migratory birds
Herons
Causes intestinal malabsorption
Chronic diarrhea
Borborygmus
Up to 2L of stool/day -> emaciation and cachexia
HF, hypokalemia, cerebral edema
Capillaria philippinensis
Fever
Vomiting
Periorbital edema
Ingestion of infected pork meat
Myalgia - cyst develop into larvae, enter blood stream and form cyst in striated muscle
Trichinella spiralis
