Mod4: Trematodes (Flukes)

Front 1

Name the 4 major diseases caused by trematodes

Back 1

a. Schistosomiasis
b. Clonorchiasis
c. Paragonimiasis
d. Cercarial Dermatitis

Front 2

describe the classification of trematodes beginning with parasites

Back 2

Parasites -> Metazoa (Helminths) -> Platyheiminthes (Flatworms) -> Trematoda (flukes)

Front 3

Name the 3 different species that cause schistomiasis

Back 3

Schistosoma mansoni
Schistosoma Japonicum
Schistosoma Haematobium

Front 4

Organism: Schistosoma mansoni
Primary Host:
Mode of Transmission
Main Sites Affected
Secondary Host

Back 4

i. Primary or Definitive Host: Humans
ii. Mode of Transmission: penetrate skin
iii. Main Sites Affected: Veins of colon
iv. Intermediate or Secondary Host(s): Snail

Front 5

Organism: Schistosoma Japonicum
Primary Host:
Mode of Transmission
Main Sites Affected
Secondary Host

Back 5

i. Primary or Definitive Host: Humans
ii. Mode of Transmission: Penetrate Skin
iii. Main Sites Affected: Veins of small intestine, live
iv. Intermediate or Secondary Host(s): Snail

Front 6

Organism: Schistosoma Haematobium
Primary Host:
Mode of Transmission
Main Sites Affected
Secondary Host

Back 6

i. Primary or Definitive Host: Humans
ii. Mode of Transmission: Penetrate Skin
iii. Main Sites Affected: Veins of Urinary Bladder
iv. Intermediate or Secondary Host(s): Snail

Front 7

Organism: Schistosoma sp.
Primary Host:
Mode of Transmission
Main Sites Affected
Secondary Host

Back 7

i. Primary or Definitive Host: Birds and Mammals
ii. Mode of Transmission: Penetrate Skin
iii. Main Sites Affected: Skin
iv. Intermediate or Secondary Host(s): Snail

Front 8

Organism: Clonorchis Sinensis
Primary Host:
Mode of Transmission
Main Sites Affected
Secondary Host

Back 8

i. Primary or Definitive Host: Humans: Humans
ii. Mode of Transmission: Ingestion of Raw Fish
iii. Main Sites Affected: Liver
iv. Intermediate or Secondary Host(s): Snail and fish

Front 9

Organism: Paragonimus Westermani
Primary Host:
Mode of Transmission
Main Sites Affected
Secondary Host

Back 9

i. Primary or Definitive Host: Humans
ii. Mode of Transmission: Ingestions of raw crab
iii. Main Sites Affected: Lung
iv. Intermediate or Secondary Host(s): Snail and crab

Front 10

Life Cycles
Organism: S. mansoni, S. hematobium, S. japonicum
stage that infects humans
human disease caused by:
important stages

Back 10

1) Stage That Infects Humans : Cercariae penetrate skin
2) Human Disease Caused by: adult flukes in mesenteric bladder veins lay eggs that cause granulomas
3.Important Stage(s) Outside of Humans: Miracidia infect snails; Cercariae infect humans

Front 11

Life Cycles
Organism: Schistosoma sp
stage that infects humans
human disease caused by:
important stages

Back 11

1) Stage That Infects Humans : Cercariae penetrate skin
2) Human Disease Caused by: allergic reaction to cercariae
3. Important Stage(s) Outside of Humans: adult flukes in birds and mammals; miracidia infect snails

Front 12

Life Cycles
Organism: Clonorchis
stage that infects humans
human disease caused by:
important stages

Back 12

1) Stage That Infects Humans : Larvae in undercooked fish
2) Human Disease Caused by: adult flukes live in biliary ducts
3. Important Stage(s) Outside of Humans: eggs ingested by snails; cercariae infect fish

Front 13

Life Cycles
Organism: Paragonimus
stage that infects humans
human disease caused by:
important stages

Back 13

1) Stage That Infects Humans : larvae in undercooked crab or crayfish
2) Human Disease Caused by: adult flukes live in lung
3. Important Stage(s) Outside of Humans : eggs ingested by snails; cercariae infect crab

Front 14

Which organisms are passed via broken skin?

Back 14

i. s. mansoni, s. hematobium, s. japonicum
ii.Schistosoma sp

Front 15

Which organisms are passed via undercooked fish?

Back 15

i. Clonorchis
ii. Paragonimus

Front 16

Schistosoma (S. mansoni, S. japocicum & S. haematobium) cause Schistosomiasis: Epidemiology
1. transmitted via?
2. definitive and intermediate hosts?
3. endemic in what areas? (3) be specific for each parasite

Back 16

i. Transmitted by penetration of skin by cercariae
ii. Humans are definitive hosts; snails are intermediate hosts
iii. Endemic in tropical areas:
1) S. mansoni in Africa and Latin America
2) S. haematobium in Africa and Middle East
3. S. japonicum: Asia

Front 17

Schistosoma (S. mansoni, S. japocicum & S. haematobium) cause Schistosomiasis: Pathogenesis (4; one for each species)

Back 17

i. Eggs in tissue induce inflammation, granulomas, fibrosis and obstruction
1) Especially in liver and spleen
ii. S. mansoni damages the colon (inferior mesenteric venules)
iii. S. japonicum damages the small intestine (superior mesenteric venules)
iv. S. haematobium damages the bladder

Front 18

Schistosoma (S. mansoni, S. japocicum & S. haematobium) cause Schistosomiasis):
Lab Dx
Rx
Prevention

Back 18

c. Lab Dx: eggs visible in feces or urine
i. Eosinophilia occurs
d. Treatment: praziquantel
e. Prevention: proper disposal of human waste
i. Swimming in endemic areas should be avoided

Front 19

Schistosoma (S. mansoni, S. japocicum & S. haematobium) cause Schistosomiasis)
1. infective stage
2. diagnostic stage

Back 19

f. Infective Stage: cercariae released by snail into water and free-swimming
g. Diagnosis Stages:
i. In Feces: S. mansoni, S. japonicum and S. heamatobium
In urine: s. haematobium & S. japonicum

Front 20

Cercarial Dermatitis:: Swimmer's Itch
1. description
2. symptoms

Back 20

a. A cutaneous inflammatory response usually associated with penetration of the skin cercariae of bird schistosomes
b. Symptoms include reddening and itching of exposed skin in the water or immediately after emerging
i. This is an indication of initial penetration of cercariae
ii. After a period of ~12 hrs, pruritic papules may becomes vesicular

Front 21

Cercarial Dermatitis: Swimmer's Itch
Life Cycle

Back 21

Life cycle:
i. Eggs passed in feces of birds after cercariae penetrate their skin and complete cycle in blood
ii. Eggs hatch and liberate miracidia
iii. The parasite develops in a molluscan intermediate host
iv. Humans are exposed to dermatitis-producing cercariae

Front 22

Clonorchis Sinensis: causes Clonorchiasis AKA Chinese or Oriental Liver Fluke
epidemiology

Back 22

i. Endemic in Asia
ii. Transmitted by eating raw or undercooked freshwater fish
iii. Humans are definitive hosts
iv. Snails and fish are first and second intermediate hosts, respectively

Front 23

Clonorchis Sinensis: causes Clonorchiasis AKA Chinese or Oriental Liver Fluke
1. pathogenesis
2. lab dx
3. treatment
4. prevention

Back 23

b. Pathogensis
i. Inflammation of biliary tract
c. Lab Dx: eggs visible in fece
d. Treatment: Praziquantel
e. Prevention: Adequate cooking of fish
i. Proper disposal of human waste

Front 24

Clonorchis Sinensis: causes Clonorchiasis AKA Chinese or Oriental Liver Fluke
Life Cycle

Back 24

Life Cycle:
i. Infective Stage: metacercariae in flesh or skin of fresh water fish are ingested by human host
ii. Diagnostic: bryonated (operculated) eggs passed in feces
iii. Intermediate Host: snail
*People that are infected have a [high] that results in hepatic dysfunction

Front 25

Paragonimus Westermani causes Paragonimiasis
1. transmission
2. definitive host
3. intermediate host
4. endemic

Back 25

a. Transmitted by eating raw or undercooked crab or crayfish meat
i. Humans are definitive hosts
ii. Snails and crabs are first and second intermediate hosts, respectively
iii. Endemic in Asia and India

Front 26

Paragonimus Westermani causes Paragonimiasis
1. pathogenesis
2. lab dx
3. Rx
4. prevention

Back 26

b. Pathogenesis: inflammation and secondary bacterial infection of lung
c. Lab Dx: eggs visible in sputum or feces
d. Treatment: praziquantel
e. Prevention: Adequate cooking of crabs
i. Proper disposal of human waste

Front 27

Paragonimus Westermani causes Paragonimiasis
riskfactors

Back 27

i. All 9 patients had consumed raw or undercooked crayfish from Missouri Rivers
ii. 8/9 were adults; 8/9 were male
iii. 7/8 adults had consumed alcohol
iv. 2/8 adults responded to dares
The child only ate raw crayfish to demonstrate outdoor survival skills to other children

Front 28

Paragonimus Westermani causes Paragonimiasis
Life Cycle:
1. infectious stage
2. diagnostic stage

Back 28

i. Infective Stage: Cercariae invade the crustacean and encyst into metacercariae after humans ingest inadequately cooked or pickled crustaceans containing metacercariae
ii. Diagnostic Stage: Unembryonated Eggs