Trematodes

Question 1

General characteristics:
Trematoda: Incomplete digestive tract
Mouth, pharynx, and esophagus
Blind-sac intestines (ceca)

Answer 1

Trematoda

Question 2

Reproductive organs of male and female in one organism or segment

Answer 2

Monoecious

Question 3

Separate male and female organisms

reproductive organs in one

Answer 3

Dioecious

Question 4

Cross-fertilization: Most often (when more than one adult is present)

Self-fertilization: When only one organism is present

Answer 4

Fertilization: Internal

Question 5

Largest subclass
Found in every major organ
Includes all ____ which parasitize man
Hosts: Intermediate, reservoir, and definitive

Answer 5

Trematoda

subclass Digenea

Question 6

Shape: The body is flattened dorso-ventrally; leaf-shaped
Monozoic: One body part

Answer 6

Trematoda: Flukes

Question 7

Suckers: Two
Oral sucker: Mouth
Ventral sucker -Acetabulum; hold-fast organ

Answer 7

Trematoda: Flukes

Question 8

Intermediate hosts
Two: Most members
One: ??

Answer 8

Schistosomes

Question 9

Operculated: Most members
Non-operculated: Schistosomes
Contains first stage larva: Most

Answer 9

OVA

Trematodes: Flukes

Question 10

Trematodes: Flukes

Larval stages: 5

Answer 10

Miracidium
Sporocyst
Redia
Cercaria
Metacercaria

Question 11

Larval Stages;
All Trematodes
Hatches in water
Ciliated

Answer 11

Miracidium

Question 12

Larval Stages:

one or more stages

Answer 12

Sporocyst

Redia

Question 13

Larval Stages:
Form which completes development in the snail and then leaves
Free swimming
Infective form to man: For dioecious organisms (Schistosomes)

Answer 13

Cercaria

Question 14

Larval stages:
Encysted cercaria
Infective form to man: For monoecious organisms

Answer 14

Metacercaria

Question 15

Tegument
Taxonomically important in ______
Described as smooth, finely tuberculated, or grossly tuberculated

Answer 15

Schistosomes

Question 16

Testes:
-Number: Taxonomically important in Schistosomes
-Position
Para
Oblique
Tandem

Answer 16

See slide 17

Question 17

Testes:
-Shape
Oval
Lobate
Dendritic or branched

Answer 17

slide 18

Question 18

Intestinal ceca:
-Shape
Straight
Undulating
Branched
Rejoined

Answer 18

slide 19

Question 19

Common name: Lung Fluke

Answer 19

Paragonimus Westermani

Question 20

Geographical distribution: Asia, South America, North America, Africa and India

Answer 20

Paragonimus Westermani

Question 21

Pathogenesis:
Tuberculosis-like symptoms
 Lung damage: Fibrosis
Migratory tissue damage
Extra pulmonary abscesses

Answer 21

Paragonimus Westermani

Question 22

Acquired through eating undercooked crustaceans carrying metacercaria

Answer 22

Paragonimus Westermani

Question 23

Causes chronic coughing, bloody sputum, fibrotic lung damage.

Answer 23

Paragonimus Westermani

Question 24

Diagnosis: Eggs found in sputum and feces

Answer 24

Paragonimus Westermani

Question 25

Common name: “Sheep liver fluke”

Answer 25

Fasciola Hapatica

Question 26

Pathogenesis Mechanical destruction of liver tissue (stimulates growth with proline) Fibrosis

Answer 26

Fasciola Hapatica

Question 27

Sheep liver fluke Worldwide distribution in grazing and wild animals. Acquired by eating metacercaria on leafy green plants (watercress)

Answer 27

F. Hepatica

Question 28

Adults in bile ducts and liver tissue, but aberrant locations are seen. Severity of disease depends on number of worms. Diagnosis: Eggs in feces, ultrasound of CT scan, ELISA

Answer 28

F. Hepatica

Question 29

Common name: Giant intestinal fluke

Answer 29

Fasciolopsis buski

Question 30

Giant intestinal fluke | Mostly found in SE Asia, India, and China

Answer 30

F. Buski

Question 31

Adults in small intestine, causes diarrhea, bile duct and intestinal blockage with heavy infection. Acquired through eating water plants with metacercaria. (fertilized with human feces) Diagnosis: eggs or adults in feces

Answer 31

F. Buski

Question 32

Common name: Chinese liver fluke

Answer 32

Clonorchis sinensis

Question 33

``` Pathogenesis Cirrhosis: Swelling of the bile ducts Blockage of the bile passages Cholangitis, pancreatitis, linked to cancer Multiple infections: Up to 21,000 adults per host ```

Answer 33

Clonorchis sinensis

Question 34

Known as Chinese liver fluke | Distribution, mostly SE Asia, China, Russia

Answer 34

C. sinensis

Question 35

Acquired by eating undercooked freshwater fish harboring metacercaria Adults in bile ducts, cause blockage, swelling, destruction Diagnosis: Eggs in feces, ELISA, CT

Answer 35

C. sinensis

Question 36

Pathogenesis: Schistosomiasis also known as bilharzia (bilharziasis) or snail fever

Answer 36

Schistosoma spp.

Question 37

Often termed Blood Flukes

Answer 37

Schistosoma spp

Question 38

Adult: Male: Flattened and rolled to form a gynecophoral groove; resembles a taco shell Female: Slender and cylindrical, fits in the groove of the male Color: Tan to gray Testes: Number characteristic of species Rejoined ceca: Length of reunited stem varies with species

Answer 38

Schistosoma spp

Question 39

Common name: Oriental blood fluke

Answer 39

Schistosoma japonicum

Question 40

Pathogenesis **MOST pathogenic: Produces **MOST EGGS per day Hepatic and pulmonary lesions Central nervous system involvement

Answer 40

Schistosoma japonicum

Question 41

Intermediate host: Fresh water snail (Oncomelania) Reservoir host: Mammals exposed to contaminated water (cattle, pigs) Infective form: Cercaria Mode of infection: Active penetration

Answer 41

Schistosoma japonicum

Question 42

Common name: Vesical blood fluke

Answer 42

Schistosoma haematobium

Question 43

Pathogenesis Urogenital tract involvement Reduced bladder capacity, obstruction, hematuria, cancer Geographic distribution: Africa, parts of Middle East Habitat: Venules of urinary bladder surrounding organs are affected

Answer 43

Schistosoma haematobium

Question 44

Intermediate host: Fresh water snail (Bulinus) Infective form: Cercaria Mode of infection: Active penetration

Answer 44

Schistosoma haematobium

Question 45

Common name: Manson’s blood fluke

Answer 45

Schistosoma mansoni

Question 46

Intermediate host: Fresh water snail (Biomphalaria) Reservoir host: Primates, insectivores, wild rodents Infective form: Cercaria Mode of infection: Active penetration

Answer 46

Schistosoma mansoni

Question 47

Eggs cause disease through obstruction, secreted antigens, cause fibrosis in various organs species dependent. Modulate immune response to Th2 Acquire through CERCARIAL skin penetration

Answer 47

Schistosomes

Question 48

Diagnosis: eggs in feces or urine (species dependent), ELISA, ultrasound, biopsy

Answer 48

Schistosomes

Question 49

Common name: Small intestinal fluke

Answer 49

Metagonimus yokogawai/Heterophyes heterophyes

Question 50

``` Habitat: Small intestines Intermediate host First: Snail Second: Fish Reservoir host: Piscivores and birds Infective form: Metacercaria Mode of infection: Ingestion ``` Common in fish markets

Answer 50

Metagonimus yokogawai/Heterophyes heterophyes

Question 51

Flukes of the small intestine, cause epigastric distress. Little damage unless heavily infected.

Answer 51

M. yokogawai and H. heterophyes

Question 52

Acquired by eating the metacercaria just under the skin of undercooked freshwater fish (carp, salmon, mullet, tilapia) Spread by using human feces as fertilizer.

Answer 52

M. yokogawai and H. heterophyes

Question 53

Diagnosis: clinical, eggs in feces but too similar to differentiate.

Answer 53

M. yokogawai and H. heterophyes

Question 54

Where are you most likely going to find Schistosoma haematobium eggs? A. Feces B. Blood C. Urine D. CSF

Answer 54

B. Blood

Question 55

Which of these trematodes is considered the lung fluke? A. Metagonimus yokogawai B. Paragonimus westermani C. Clonorchis sinensis D. Diphyllobothrium latum

Answer 55

B. Paragonimus westermani