FINALS: Fasciola species (Liver Flukes)

Question 1

“temperate liver fluke”

Answer 1

Fasciola hepatica

Question 2

“tropical liver fluke”

Answer 2

Fasciola gigantica

Question 3

Digenetic

Answer 3

Fasciola species

Question 4

Definitive host:

Answer 4

humans, sheep, goat, cattle

Question 5

MOT:

Answer 5

ingestion of metacercariae on aquatic plants or by drinking water infected with metacercariae

Question 6

1st Intermediate Host
Fasciola hepatica

Answer 6

Lymnaea truncatula
Lymnaea bulmoides
Lymnaea tomentosa
Planorbidae

Question 7

Lymnaea truncatula

Answer 7

Europe and North Asia

Question 8

Lymnaea bulmoides

Answer 8

North America

Question 9

Lymnaea tomentosa

Answer 9

Australia

Question 10

1st Intermediate Host
Fasciola gigantica

Answer 10

Lymnaea auricularia
Lymnaea acuminata
Lymnaea natalensis
Lymnaea philippinensis
Lymnaea auricularia rubiginosa

Question 11

Lymnaea auricularia

Answer 11

Asia

Question 12

Lymnaea acuminata

Answer 12

India

Question 13

Lymnaea natalensis

Answer 13

Africa

Question 14

Lymnaea philippinensis
Lymnaea auricularia rubiginosa

Answer 14

PHILIPPINES

Question 15

2nd Intermediate Host

Answer 15

Ipomea obscura
Nasturtium officinale

Question 16

Ipomea obscura

Answer 16

Morning glory or kangkong

Question 17

Nasturtium officinale

Answer 17

Watercress

Question 18

Infective Stage:

Answer 18

metacercariae

Question 19

Diagnostic Stage:

Answer 19

unembryonated egg

Question 20

• Shape: ovoid, large • Color: yellowish to brownish • Operculated • Contains a large unsegmented mass of vitelline cells
• F. hepatica: 140-180 um by 63-90 um
• F. gigantica: 160-190 um by 70-90 um

Answer 20

eggs

Question 21

• Excyst in duodenum
• Penetrates the intestinal wall into the peritoneal cavity

Answer 21

Metacercariae

Question 22

Immature worms migrate through the liver parenchyma into the biliary ducts and mature

Answer 22

Adult Worm

Question 23

larval migration and worm maturation
o Symptoms: dyspepsia, fever, and pain in the right upper quadrant abdomen
o Cardinal signs: sudden onset of high fever, hepatomegaly, and eosinophilia

Answer 23

Acute or invasive phase

Question 24

worms in the biliary ducts o Symptoms: biliary obstruction, biliary cirrhosis, and obstructive jaundice
o Asymptomatic

Answer 24

Chronic or latent phase:

Question 25

Fascioliasis: damage to the liver parenchyma can produce traumatic and necrotic lesions

Answer 25

Acute phase

Question 26

Fascioliasis: damage to the liver parenchyma can produce traumatic and necrotic lesions

Answer 26

Acute phase

Question 27

Fascioliasis: obstruction stimulates inflammation in the biliary epithelium, causing fibrosis

Answer 27

Chronic phase

Question 28

Rare complication:

Answer 28

acute pancreatitis

Question 29

Hemorrhagic nasopharyngitis and
dysphagia:

Answer 29

flukes surviving mastication that attach to posterior pharynx

Question 30

Lebanon:

Answer 30

halzoun

Question 31

Sudan:

Answer 31

marrara

Question 32

• Identification of eggs in stool, duodenal contents, or bile
• Recovery of adult worms during surgery, after treatment, or at autopsy
• ELISA and Western blot
• CT scan
• Endoscopic retrograde
cholangiopancreatography: diagnoses fascioliasis in the biliary phase

Answer 32

Diagnosis

Question 33

Treatment

Answer 33

• Triclabendazole: 10 mg/kg single dose
• Bithionol: alternative drug; 30-50 mg/kg on alternate days for 10-15 doses