Cestodes Flashcards
Scolex
Anterior end of tapeworms which functions as an attachment organ using suckers, hooks, or grooves. Serves as site selection anchor
What is the reproductive unit of hermaphroditic tapeworms and what is the term for all these units together?
Proglottid. All units together make up the strobila
What hosts are involved in the hymenolepis nana (dwarf tapeworm) life cycle
Just one host No intermediate hosts
Symptoms of hymenolepis nana (dwarf tapeworm) infection
Usually asymptomatic. Can have diarrhea, abdominal pain, anorexia, nervous disorders
What is the most frequently detected tapeworm in the US?
Hymenolepis nana (dwarf tapeworm) |S S p750
Intermediate hosts in diphyllobothrium latum
Copepods and fresh water fish
Where in the body does diphyllobothrium latum live?
Small intestine
What type of organism is hymenolepis nana?
Cestode (tapeworm)
What type of organism of diphyllobothrium latum?
Cestode (tapeworm)
Symptoms of diphyllobothrium latum infection
Usually asymptomatic. Can have diarrhea, heartburn, nausea, vomiting, pernicious anemia
What type of organism is taenia saginata?
Cestode (tapeworm). Also called beef tapeworm
Where in the body do taenia saginata live?
Small intestine
How do humans become infected with taenia saginata?
Eating infected meat (the larvae (cysticercus) live in cattle muscle
Symptoms of taenia saginata infection
Usually asymptomatic, anal discomfort, diarrhea, abdominal cramps
What is the most effective means of diagnosis for taenia saginata infection?
Cellophane tape to check for eggs in the perianal area
What type of organism is taenia solium?
Cestode (tapeworm). Also called pork tapeworm
Where in the body does taenia solium live?
Small intestine
Where in the body are taenia solium larvae (cysticercus) found?
CNS, skeletal muscle or myocardium, subcutaneous tissue, eye, lungs, liver
Symptoms of taenia solium infection
Can have epileptic seizures, hydrocephalus, strokes when larvae die in brain. Other symptoms less serious
Which can be differentiated between taenia saginata and taenia solium, the eggs, proglottids or both?
Just the proglottids (eggs appear identical)
Treatment options for taenia solium infection
Cysticercus - Surgery or chemotherapy, Adults - must expell proglottids in complete form
What type of organism is echinococcus granulosus?
Cestode (tapeworm). Its hydatid cyst is what causes human disease
Where do larvae of echinococcus granulosus live in the body and how do they get there?
Swallowed, through intestinal wall to mesenteric venule to lodge in liver (most common), lungs, CNS, bone, or other tissue
What is hydatid sand composed of?
Multiple hydatid scoleces comprised of parasite-derived internal germinal membrane and host-derived external laminated cuticle
