Parasites Flashcards
What type of parasite is giardiasis
Flagellate protozoan
Trophozoite
live adult protozoa
transmission of giardia
fecal oral
What part of the body does giaridia affect
duodenum and jéjunum. The crypts hypertropy and villous flatten. Caused by irritation and inflammation
Giardia work up:
stool smear (3x) Stool enzyme linked immunsorbent assay (ELISA)
Tx Giardia
Flagyl
Two amoebias that cause disease
E.histolyica and Dientamoeba fragilis
maturation process of amoeba
trophozoite emerges from ingested cyst in the stomach or duodenum. They divide again and move to the cecum and cause problems in the mucosal surface by invading the bowel wall, forming ulcers, and perforation in the peritoneal cavity
Factors that determine invasion of amoebas
number ingested
pathogenic capacity of the parasite strain
host factors gut motility and immune competence
microemboli due to amoeba trophozoites carried through portal circulation causes?
Hepatitis and liver abscess
Amoeba Dx
stool specimen
serology
Why is E.histolytica different and how do you tx?
higher risk of invasive disease. Use Paromomycin (asymptomatic) or metronidazole (symptomatic)
malaria transmission
mosquitoes inject sporozoites(protozoa) that circulate to the liver and multiple within hepatocytes
most deadly malaria parasite species
Plasmodium falciparum, because it invades RBC of any age and causes agglutination forming thrombi and emboli
malaria symptoms
spleno/hepatomegaly in chronically infected pt
congenital malaria
febrile newborn
Malaria tx
chloroquine(resistance) atovaquone hydroxychloroquine doxycycline mefloquine(larium)
malaria prophylaxis
chloroquine or primiquine
Crytosporidiosis
protozoan, associated with municipal water supple due to resistance of chlorine
Fecal/Oral. Very small and you only need one to be infected
Crytospordiosis infection sites
epithelial of the GI, respiratory tract and conjunctiva of eyes. Cell damage occurs via T-cell mediated inflammation….microvilli death
Crytospord Dx
stool sample 3x
Enzyme immunoassay using PCR
Toxoplasma gondii
protozoan, cats are the only host that allows the parasite to fully mature. 3rd cause of death attributed to food borne illness. In lamb and pork Normally immune system keeps parasite from causing illness
toxo pathophysiology
oocyts releases spores in the duodenum, they pass through gut wall, circulate in the body and infect various cells including macrophages/lymph nodes and penetrate nerve cells(brain and eyes)
toxo symtoms
hepatitis, pneumonia, blindness & neurologic disorder
toxo congential
only occurs when pregnant mother is infected=baby can be blind, hydrocephaly, psychomotor disturbances
toxo prenatal
blinds, enlarged spleen and liver
Ocular toxo
multiple recurrences may cause glaucoma
Toxo DX
blood contains specific antibodies, sputum, BM and CFS can also be used
why change litter box daily
takes 48 hours for oocytes to become infective
Tx toxo
trimethoprim, bactrim
Pinworms (Helminths)
enterobius vermicularis, fecal/oral. live in colon and cecum will crawl out during the night. Itchy butt
pinworm dx
stool for ova and worm or tape test
pinworm tx
pyrantel pamoate or mebendazole(vermox)
Round worm
ascariasis
round worm pathophysiology
hatch in small intestine, blood stream to lungs, coughed up and swallowed go to the lumen of the intestine where they live off of ingested food but don’t attach to the wall
Clinical findings roundworms
damage occurs to the lungs where inflammation caused by eosinophilic exudate response to larval antigens or intestinal obstruction
dx roundworm
stool sample and use mebendazole
Hookworm
Necator americanus
Hookworm pathophysiology
barbs pentrate skin, bloodstream to lungs to small intestine where they attach the wall and feed on blood
hookworm clinical findings
blood loss, microcytic anemia and pneumonia with eosinophilia can be seen during larval migration through the lungs
hookworm Dx and Tx
stool sample for parasite and blood
Eosinophilia is common
mebendazole and pyrantel pamoate
Trichinosis
pigs and other animals, infected by eating uncooked meat. the larva only fully develop in the muscle cells where they hide from macrophages
trichinosis clinical findings
diarrhea, fever, muscle pain periorbital edema and eosinophilia, subconjunctival hemorrhages. death is caused by congestive heart failure
dx trichinosis
muscle biopsy
tx trichinosis
no tx
Dog worm
Toxocara canis, major cause of larvae migration to many organs including brain, eyes and liver. B/c humans are not the final host, issues are from larvae death
Dog worm clinical findings
visceralis larva migrans and occular larva migrans
granulomas are formed from dead larvae and delayed hypersensitive response to larval proteins
Fever hepatomegaly, and eosinphilia
Dog worm Occular larva migrans
unilateral visual impairment, strabismus and white elevated lesions
What age is affected by dogwood?
young children (common parasite in domestic dogs)
Dx dogworm
serologic, hypergammaglobulinemia and eosinphila
tx dogworm
albenazole and mebendazole
Anisakiasis
ingesting raw seafood caused by nematode
Anisakiasis S/S
GI, abdominal pain, eosinphilia, blood in stool, appendicitis and chronic infection
Anisakiasis Dx
endoscopically or laparotomy. Serology: DO NOT help . NO TREATMENT
Cestodes (tapeworm) Taenia
T. solium (pork) and T.saginata (beef)
Cestodes (tapeworm) Taenia S/S and Tx
GI issues, gravid proglottids branches in the stool Use: Praziquantel
