Cestodes

Front 1

Cestodes are also known as _____.

Back 1

tapeworms

Front 2

Cestodes are called tapes worms because being ______, and _______like adult shaped worms. The adults are _________ meaning both sexesare combined in one organism.

Back 2

flat,

ribbon,

hermaphroditic,

Front 3

Cestode adults measure from _____to _____. The parasite is ______ with ahead and body. The head is called a ______ which is the generation pointfor new segments (or ______). The _______ chain together to formthe body of the worm.

Back 3

3 mm to 75 feet,

multicellular,

scolex,

proglottids,

proglottids,

Front 4

Life cycle Cestode...The infection is acquired through the ingestion of _____ embedded in the ______ tissue of an infective animal host. The cyst develops in the stomachand intestine into a new ______ which attaches to the intestinal wall. Fromthe scolex, _______ develop and begin to produce eggs. The matureegg-producing proglottid is referred to a ________.

Back 4

cysts,

muscle,

scolex,

proglottids,

gravid

Front 5

Life cycle of Cestode...The eggs are voided in the stool and sometimes the oldest ______ arealso shed which contain lots of eggs. An ______ host ingests theeggs from contaminated soil and develops in the _____ tissue of this host.The cycle repeats with humans ingesting the meat.

Back 5

proglottids,

intermediate,

muscle,

Front 6

List the five common Cestodes.

Back 6

-Diphyllobothrium latum,

-Taenia species,

-Hymenolepsis tapeworms,

-Dipylidium caninum,

-Echinococcus granulosus.

Front 7

Diphyllobothrium latum is commonly known as the ______ or the ________ as the segments are sometimes wider than they are long.

Back 7

fish tapeworm,

broad tapeworm,

Front 8

Diphyllobothrium latum, humansbecome infected by ingesting ________ larvae embedded in cysts in themuscle tissue of raw or undercooked fresh water fish. The adult wormmeasures up to _____ meters in length with approximately _______ proglottids,producing millions of eggs each day for each worm. For this reason, it maynot be necessary to concentrate the stool sample to find the eggs butlaboratories still do as it is part of the O & P standard processing. Thescolex has suction slits for attachment called ________.

Back 8

plerocercoid,

10,

3000,

bothria

Front 9

Diphyllobothrium latum is native to _____, the ______, and parts of _______. It is alsovery common in the Midwest & _______ & Pacific NW - perhaps because immigrants brought it with them. It is associated with _______ fish delicaciesor freshly caught fish exposure while cleaning/preparing.

Back 9

Scandinavia,

Baltics,

Russia,

Great Lakes,

pickle/smoked

Front 10

The _____ attaches via suction to the intestinal wall and absorbs nutrientsthrough the surface of the parasite from the host digestive track. The patientsoften show _____ due to vitamin B12 deficiency. The life cycle of D. latum isa bit more complex than other tapeworms with 2 intermediate hosts (a _____ & a _____) before infecting a human.

Back 10

scolex,

anemia,

crustacean

fish

Front 11

Most patients are ________ if infected with D. latum, however, those with long term infections ormultiple tapeworms may develop _________ from a dietary deficiency ofvitamin B12. Individuals who present with macrocytic anemia should have anexamination for _______ as part of their differential diagnosis.

Back 11

asymptomatic,

macrocytic anemia,

Ova & Parasites

Front 12

The _____ of D. latum are diagnostic. They are quite distinct. They are oval,about ____ um, possess an ______ and a knob on the opposite end.The _______ is like a cap that opens up and releases the worm. It may bedifficult to see and may appear as a slight bump on the outline of the egg.To find each of these characteristics, multiple eggs may need to beobserved.

Back 12

eggs,

40-60,

operculum,

operculum,

Front 13

Identify this organism.

Back 13

Diphyllobothrium latum worm form.

Notice the bothria for attachment and sucking on the scolex. Also noticeeach proglottid is wider than they are long. The proglottids chain togetherto form the body of the worm.

Front 14

Identify this organism.

Back 14

Diphyllobothrium latum egg form

with operculum and knobby tail

Front 15

List the Taenia species.

Back 15

Taenia saginata,

Taenia solium

Front 16

Taenia saginata is the _____tapeworm andTaenia solium is the ______ tapeworm. The eggs of these two speciesare indistinguishable from each other and are studied together. To differentiate,observation of the ______ is necessary as well as the segments form of the adulttapeworm.

Back 16

Bovine,

porcine (pig)

scolex

Front 17

Humans become infected with Taenia species by ingesting raw orundercooked meat from an animal with ________ cysts embedded in the ______ or ______ tissue. The infection can be prevented by _______ the meatand avoiding contamination of kitchen utensils when preparing other food.The risk of infection is contained in the U.S. by treating herd animals usedin food production for the parasite. Outside the U.S., the regulations formonitoring the meat may not be as stringent.

Back 17

cysticercoid,

muscle,

organ,

cooking

Front 18

Taenia is found in areas of the world with high beef or pork diets. It mayalso be found in buffalo and bear meat. The meat contains _____ which are ingested and begin the infection, which also referred to as a ______ embryo or ______ egg.

Back 18

oncospheres,

hexacanth,

taenia

Front 19

Cysticercosis which is caused by _______.

Back 19

Taenia solium

Front 20

Taenia saginata, or beef tapeworm, has ____ suckers on the scolex but no ______ of hooks. This is one of the characteristics that differentiate theorganism from ______. The _______ are also longer than T.solium with greater than ___ uterine branches per proglottid. The adultmay reach ___ meters in length.

Back 20

four,

rostellum,

Taenia solium,

proglottids,

13,

12

Front 21

Taenia solium or _______ has ____ suckers with a ______ of hooks.The adult work has shorter segments than ______and less than 13uterine branches per proglottid. It may reach up to ____ meters in length.

Back 21

Pork tapeworm,

four,

rostellum,

Taenia. saginata,

7

Front 22

Identify this organism.

Back 22

Taenia solium

New proglottids are generated from the neck area. The newer proglottidsare immature and are shorter in length than the mature and gravidproglottids toward the middle and end of the worm.

Front 23

The _____ is diagnostic stage for Taenia but cannot be differentiated for the T. species. Need to view the _____of worm to make final identification. Theyare naturally _____color with a thick double layer shell which may demonstrate ______. Inside the egg, ______ of the new scolex may be visible.

Back 23

egg,

scolex,

brown,

striations,

hooklets,

Front 24

Identify.

Back 24

Taenia species eggs

These are the eggs of the Taenia species. They are indistinguishable fromeach other. Notice the thick wall with striations and hooks that are visibleinside.

Front 25

Identify the left from the right.

Back 25

Left - Taenia saginata

Right - Taenia solium

T. saginata (left) longer segments, > 13 uterine branches, suckers but norostellum.T. solium (Right), shorter segments, <13 uterine branches, suckers androstellum (hooks). Solium - letter 'o' in solium, pork, and rostellum; the word solium is shorterthan saginata which is similar to the length of the worm. May also be usedto demonstrate which has fewer uterine branches and shorter segments.

Front 26

T. solium does not always require an _____ host for human infection.Humans that ingest the ____ of the parasite from tissue cysts in striated muscleor other tissues - just like it would in porcine hosts. This is called ______.If cysticercosis occurs in _____, the patient will be ok (well, ouch) but, if itoccurs in the ____ it can be fatal.

Back 26

intermediate,

eggs,

cysticercosis,

muscle,

brain,

Front 27

List the two species of Hymenolepsis tapeworms.

Back 27

Hymenolepsis nana

Hymenolepsis diminuta,

Front 28

H. nana is called the _____tapeworm

Back 28

Dwarf

Front 29

H. nana is called the ____ tapeworm as the adult is only ___ cm long.Hymenolepsis nana and Hymenolepsis diminuta are two species that mayinfect man with ___ being more common than H. diminuta. The eggsare similar but may be distinguished from each other. The host becomesinfected after the ingestion of the ___ or an arthropod intermediate host.

Back 29

dwarf,

2-4,

H. nana,

egg

Front 30

The H. nana infection is more common as the egg can immediately be _____ upon release form the body, it requires no _____host,and ______ may occur if the egg hatches before being releasedfrom the body.

Back 30

infectious,

intermediate,

auto-infection,

Front 31

H. diminuta is the ____ because rats/mice are the intermediate hosts.Human infections are far less common and become infected when theyaccidentally ingest ______ that are infected with the organism or byeating infested grains or handling barn feed.The tapeworm can be up to _____ meters long. The egg has a ______ shell but no ______.

Back 31

rat tapeworm,

arthropods (fleas),

0.6,

double,

polar filaments,

Front 32

The eggs of H. nana and H. diminuta are ____ to slightly oval, _____ um insize, and have an ____ and ____ shell. H. diminuta has ______.Although adults of H. nana only live for ____weeks, auto-reinfection allows theinfection to continue for years.

Back 32

round,

oval,

60-80,

inner,

outer,

no filaments,

4-6

Front 33

Identify

Back 33

H. nana.

The inner shell of H. nana has 2 knobs with polar filaments that spread outbetween the egg shell layers. Notice the filaments between the layers inthese pictures. Be careful as the wall can pull away from the outer layerand fold, making it look like it has filaments.

Front 34

Identify

Back 34

H.dimunthia

H. diminuta has no filaments. The hooks are visible inside the inner shellfor both species.

Front 35

Dipylidium caninum is a _______ that may infect pets as well as wildcanine species. Humans become infected by accidentally ingesting infecteddog fleas. This is more common if the pet is untreated or has a heavy fleainfestation. Children are the most likely host due to the close proximity topets, general lack of hygiene, and the fact that contaminated hands andtoys are highly possible.

Back 35

dog tapeworm,

Front 36

Identify

Back 36

dipylidium caninum

The proglottids have more of a rounded appearance. The embryonatedeggs are found in packets.

Front 37

___ is another dog tapeworm that can also beharbored by ___. It may cause a life threatening infection called ___ disease in humans. Humans become infected by accidentally ingestingeggs in dog feces directly or in contaminated soil. Humans are anaccidental host. Because the organism is not directed toward humaninfection, they do not stay within the intestines and migrate tovarious tissues throughout the body.

Back 37

Echinococcus granulosus,

cats,

Hydatid Cyst

Front 38

Identify

Back 38

Echinococcus granulosus

The hydatid cyst may contain numerous developing protoscoleces. Theprotoscoleces are developing tape worms and are present in the picture onthe right. On the left is the hexacanth of this organism.