TREMATODES (MONOECIOUS FLUKES) Flashcards
Sheep liver fluke
Fasciola hepatica
Giant Liver Fluke
Fasciola gigantica
Chinese Liver Fluke/Oriental Liver Fluke
Clonorchis sinensis
Cat Liver Fluke
Opistorchis felineus
Southeast Asian Liver Fluke
Opistorchis viverrini
Lancet fluke/Lanceolate fluke
Dicrocoelium dendriticum
➢ Large and ellipsoidal
Fasciola hepatica
➢ Thin-shelled with distinct operculum
Fasciola hepatica
➢ Yellowish to light brown in color
Fasciola hepatica
➢ Immature when laid
Fasciola hepatica
- Greater in length,
shorter cephalic cone
Fasciola gigantica
- Larger ventral sucker
Fasciola gigantica
- Reproductive organs are
located on the anterior
portion of the worm
Fasciola gigantica
- The ovum is bigger
Fasciola gigantica
The ova of F. hepatica and F. gigantica are similar although F. gigantica egg is bigger
Fasciola gigantica
➢ Yellowish-brown with distinct convex operculum
Clonorchis sinensis
➢ Resembles an “old fashion” electric bulb
Clonorchis sinensis
➢ Fully embryonated when laid
C. sinensus
Opistorchis felineus
➢ Yellowish-brown, ovoid
O. felineus
Opistorchis viverrini
➢ Measuring about 26-30 um by 15-17 um
O. felineus
Opistorchis viverrini
➢ With distinct convex operculum and a small protuberance at the abopercular end
O. felineus
Opistorchis viverrini
➢ Fully embryonated when laid
C. sinensus
Opistorchis felineus
Opistorchis viverrini
➢ Operculated and measure 35-45 μm long by 20-30 μm wide
Dicrocoelium dendriticum
➢ The eggs are thick-shelled and usually dark brown in color
Dicrocoelium dendriticum
➢ Eggs are fully embryonated when shed in feces.
Dicrocoelium dendriticum
➢ Large broad and flat body which measures about 20-50 mm in length and 6-12 mm in width
Fasciola hepatica
➢ A distinguishing feature is the cephalic cone which has a marked widening at the base of the cone (“shoulder”).
Fasciola hepatica
➢ Testes: tandem formation and highly branched
Fasciola hepatica
➢ Vitellaria: branched, found in lateral and posterior portion
Fasciola hepatica
➢ Ovary: branched/dendritic; located posterior to uterus and anterior to testes
Fasciola hepatica
➢ Uterus: short and coiled
Fasciola hepatica
adult worm is longer and its “shoulder” (cephalic cone) is less developed
Fasciola gigantica
➢ Ceca are more branched
Fasciola gigantica
➢ Branches of ovary are longer and more numerous
Fasciola gigantica
➢ Flat, transparent, elongated, rounded posteriorly and attenuated anteriorly
Clonorchis sinensis
➢ Cuticle – smooth and shiny
Clonorchis sinensis
➢ Ventral sucker – smaller than oral sucker
Clonorchis sinensis
➢ Testes – branched, arranged in tandem
Clonorchis sinensis
➢ Resembles Clonorchis sinensis
Opistorchis felineus
➢ Slightly shorter than C. sinensis measuring about 8-12 mm long and 1.5 to 3 mm wide
Opistorchis felineus
➢ Leaf-like in shape with transparent tegument
Opistorchis felineus
location of vitellaria, which are found in the middle third of the body at the level of the uterus
Opistorchis felineus
➢ Whereas the main difference is in the morphology and arrangement of testes
Opistorchis felineus
➢ Lobate testes, arranged obliquely
Opistorchis felineus
➢ Slightly similar as O. felineus
Opistorchis viverrini
adult in that the are positioned close to each other and are more deeply lobulated
Opistorchis viverrini
➢ Slender, lancet- shaped, flat
Dicrocoelium dendriticu
➢ Testes: Slightly lobulated, situated obliquely to each other anterior to the small subglobous ovary
Dicrocoelium dendriticu
➢ Oral sucker: smaller than ventral sucker
Dicrocoelium dendriticu
➢ Vitellaria: Scanty
Dicrocoelium dendriticu
1st IH:
- Water snail (Lymnea)
Fasciola hepatica
Fasciola gigantica
1st IH: Operculated snails
o Parafossarulus
o Bulimus
o Semisulcospira
o Alocinma
o Thiara
o Melanoides
Clonorchis sinensis
1st IH:
- Bithynia leachi
Opistorchis felineus
1st IH:
- Bithynia spp.
Opistorchis viverrini
1st IH: Land snails
o Cochicella
o Helicella
o Zebrina
Dicrocoelium dendriticum
2nd IH:
- Ipomea obscura (kangkong) - Nasturtium officinale (water cress)
Fasciola hepatica
Fasciola gigantica
2nd IH: Fresh water fish o Tingea tingea
o Barbus barbus
Clonorchis sinensis
2nd IH:
- Fresh water fish (Idus melanotus, Tinca tinca, Cyprinos carpio)
Opistorchis felineus
2nd IH:
- Fresh water fish
Opistorchis viverrini
2nd IH: Ants (Formica fusca)
Dicrocoelium dendriticum
METACERCARIA
Fasciola hepatica
Fasciola gigantica
Clonorchis sinensis
Opistorchis felineus
Opistorchis viverrini
Dicrocoelium dendriticum
Bile passages/bile ducts of fish- eating mammals
Clonorchis sinensis
Distal ducts occasionally pancreatic duct
Opistorchis felineus
Biliary ducts
Opistorchis viverrini
found in areas where sheep and cattle are raised and where humans consume raw watercress (Europe, Middle East and Asia)
Fasciola hepatica
more rarely in Asia, Africa, and Hawaii
Fasciola gigantica
Europe and Asia, including the former Soviet Union
Opistorchis felineus
Europe and Asia
Opistorchis viverrini
common parasite of ruminants but humans can be accidental definitive hosts
Dicrocoelium dendriticum
o Liver rot disease/Fascioliasis hepatica
Fasciola hepatica
o Acute phase: (migration of the immature fluke through the hepatic parenchyma)
Fasciola hepatica
➢ Abdominal pain, diarrhea, vomiting
Fasciola hepatica
➢ Hepatomegaly, fever, urticaria
Fasciola hepatica
➢ Eosinophilia
Fasciola hepatica
o Chronic phase: (adult fluke within the bile ducts)
Fasciola hepatica
➢ Intermittent biliary obstruction and inflammation
Fasciola hepatica
➢ Ectopic locations of infection (intestinal wall, lungs, subcutaneous tissue, and pharyngeal mucosa)
Fasciola hepatica
Diagnosis
1. Direct fecal smear examination
Fasciola hepatica
Diagnosis
2. Concentration sedimentation techniques
Fasciola hepatica
Diagnosis
3. Antibody detection
Fasciola hepatica
o Fascioliasis
Fasciola gigantica
Diagnosis
Same with F. hepatica
Fasciola gigantica
o Clonorchiasis
Clonorchis sinensis
o Carcinoma of the liver, adenocarcinoma of the gall bladder, as well as pancreatitis
Clonorchis sinensis
o Inflammation and intermittent obstruction of the biliary ducts → irritation of the bile ducts
Clonorchis sinensis
o Early infection:
➢ Leukocytosis and eosinophilia
Clonorchis sinensis
o Acute infection:
➢ Chills and fever up to 40°C
➢ Enlargement and tenderness of the liver;
Clonorchis sinensis
o Chronic infection:
➢ In the chronic stage, the clinical presentation may range from asymptomatic to mild to severe disease
Clonorchis sinensis
o Chronic infection:
➢ Cirrhosis and portal hypertension are present
Clonorchis sinensis
o Chronic infection:
➢ Cholangitis, cholelithiasis, cholangiocarcinoma, and pancreatitis
Clonorchis sinensis
Diagnosis
1. Eggs in biliary drainage (most practical diagnostic method)
Clonorchis sinensis
Diagnosis
2. Adult worms can be recovered through surgery
Clonorchis sinensis
Diagnosis
3. Liver scan
Clonorchis sinensis
Diagnosis
4. Phosphoglycerate kinase (a glycolytic enzyme) – can be used as an immunoreagent in the serodiagnosis for clonorchiasis
Clonorchis sinensis
Diagnosis
5. Serologic tests: ELISA, EIA
Clonorchis sinensis
o Opistorchiasis
Opistorchis felineus
Opistorchis viverrini
o Most infections are asymptomatic
Opistorchis felineus
Opistorchis viverrini
o Mild cases:
➢ Dyspepsia, abdominal pain, diarrhea, constipation
Opistorchis felineus
o Acute infections:
➢ Resembles Katayama fever
➢ Fever, facial edema, lymphadenopathy, athralgia, rash, eosinophilia
Opistorchis felineus
o Chronic infections:
➢ Hepatomegaly and malnutrition
Opistorchis felineus
o Rare cases:
➢ Cholangitis, cholecystitis, cholangiocarcinoma
Opistorchis felineus
Diagnosis
1. Direct Fecal smear
Opistorchis felineus
Diagnosis
2. Eggs in duodenal aspirate
Opistorchis felineus
o Most pathologic manifestations result from inflammation and intermittent obstruction of the biliary ducts.
Opistorchis viverrini
o Clinical manifestations: same with O.felineus
Opistorchis viverrini
Diagnosis
Same as O. felineus
Opistorchis viverrini
the eggs of C. sinensis, O. viverrini, and O. felineus are difficult to differentiate. However, when stained with KMnO4 and examined under a 400x magnification of a light microscope show distinct melon- like ridges on the surface of
Opistorchis viverrini eggs
o Dricocoeliasis
Dicrocoelium dendriticum
o Chronic constipation and hepatomegaly
Dicrocoelium dendriticum
Diagnosis
o Diagnosis is based on microscopic identification of eggs in the stool, duodenal, and/or bile fluid
Dicrocoelium dendriticum
Diagnosis
o Note that eggs may be detected in stool following consumption of liver infected with adult flukes
Dicrocoelium dendriticum
Diagnosis
o Additional specimens should be collected to distinguish this spurious passage from a true infection.
Dicrocoelium dendriticum
Diagnosis
o Adult flukes are rarely recovered
Dicrocoelium dendriticum
- Thorough washing or cooking of vegetable
Fasciola hepatica
Fasciola gigantica
- Boiling of water in areas where the infection is endemic
Fasciola hepatica
Fasciola gigantica
- Eradication/elimination of the snail intermediate hosts
Fasciola hepatica
Fasciola gigantica
- Treatment of positive cases with praziquantel in order to eliminate human host reservoir
Clonorchis sinensis
Opistorchis felineus
Opistorchis viverrini
- Health education for the promotion of cooked fish consumption in order to prevent infection
Clonorchis sinensis
Opistorchis felineus
Opistorchis viverrini
- Proper human waste disposal in order to interrupt the transmission of the disease
Clonorchis sinensis
Opistorchis felineus
Opistorchis viverrini
- Bithionol (treatment of choice)
Fasciola hepatica
Fasciola gigantica
- Emetine hydrochloride
Fasciola hepatica
Fasciola gigantica
- Praziquantel
Clonorchis sinensis
- Chloroquine phosphate
Clonorchis sinensis
- Praziquantel (drug of choice)
Opistorchis felineus
Opistorchis viverrini
It was first discovered by Busk in 1843, in the duodenum of an East Indian sailor who died in London. This fluke has been featured under a variety of names, due to its size, different shapes, and differences in integumentary spine pattern.
Fasciolopsis buski
Garrison first found the eggs of this fluke in native prisoners in Manila in 1907, and later recovered 21 adult worms after administration of oleoresin of aspidium. Tubangui in 1931 found that the Norway rat was a reservoir of the infection.
Echinostoma ilocanum
this minute fluke was first found by Bilharz in 1851 at the autopsy of a native Cairo
Heterophyes heterophyes
Largest Intestinal Fluke
Fasciolopsis buski
Garrison’s Intestinal fluke
Echinostoma ilocanum
Dwarf Intestinal Fluke; Von Seibold Fluke
Heterophyes heterophyes
Yokogawa’s human fluke;
smallest human fluke
Metagonimus yokogawai
Asia and the Indian subcontinent, especially in areas where humans raise pigs and consume freshwater plants
Fasciolopsis buski
Population of Ilocano in Luzon, Java and China where dogs are infected
Echinostoma ilocanum
Mostly the Far East, Siberia, Balkan States, Israel, and Spain
Metagonimus yokogawai
METACERCARIA
Fasciolopsis buski
Echinostoma ilocanum
Metagonimus yokogawai
Small intestine and sometimes in Large intestine and stomach
Fasciolopsis buski
Small intestine
Echinostoma ilocanum
Heterophyes heterophyes
▪ 1st snail IH: Planorbid snails o Segmentina
o Hippeutic
o Gyraulus
Fasciolopsis buski
▪ 1st snail IH: Planorbid snails
o Gyraulus convexiusculus (Philippines and Java) o Hippeutis (Philippines)
o Gyraulus prashadi (India)
Echinostoma ilocanum
▪ 1st intermediate host: Brackish water snails o Pirenella
o Cerithidea
Heterophyes heterophyes
▪ 1ST intermediate host: Semisulcospira, Thiara, Hua
Metagonimus yokogawai
▪ 2nd IH: Aquatic plants
o Trapa bicornis (water caltrop) o Eichuora (water hyacinth)
o Eliocharis tuberosa (water chestnut)
o Nymphaea lotus (lotus)
Fasciolopsis buski
▪ Definitive host: Man and Pigs
Fasciolopsis buski
▪ 2nd IH: Fresh water Mollusks
o Pila conica
Echinostoma ilocanum
▪ 2nd intermediate host: Fish
o Mugil cephalus o Tilapia nilotica
Heterophyes heterophyes
▪ 2nd intermediate host: Fresh water salmonoid fishes
Metagonimus yokogawai
- Ova/Eggs
➢ Large, has a clear thin shell with a small operculum at one end
Fasciolopsis buski
- Ova/Eggs
➢ Resembles “hen’s egg”
Fasciolopsis buski
- Ova/Eggs
➢ Immature when passed in feces; usually it takes 3-7 weeks to embryonate in water
Fasciolopsis buski
- Ova/Eggs
➢ Straw-colored with operculum at one end
Echinostoma ilocanum
- Ova/Eggs
➢ Measures 83-116 um by 58-69 um
Echinostoma ilocanum
- Ova/Eggs
➢ Immature when passed in the feces
Echinostoma ilocanum
- Ova/Eggs
➢ Light brown in color, thick shelled, operculated minute egg
Heterophyes heterophyes
- Ova/Eggs
➢ Contains fully developed miracidium
Heterophyes heterophyes
- Ova/Eggs
➢ Indistinguishable from H. heterophyes
Metagonimus yokogawai
- Adult
➢ Thick, flesh in color
Fasciolopsis buski
- Adult
➢ Cuticle is covered with transverse row of spines
Fasciolopsis buski
- Adult
➢ Testes: dendritic or highly branched and in tandem positioned at the posterior half of the worm
Fasciolopsis buski
- Adult
➢ Ovary: branched and located at the middle of the body
Fasciolopsis buski
- Adult
➢ Vitellaria: highly branched
Fasciolopsis buski
- Adult
➢ Elongated, reddish-gray with horse-shoe shaped collar of spines surrounding the dorsal and lateral sides of oral sucker
Echinostoma ilocanum
- Adult
➢ Cuticle: with minute spine-like scales
Echinostoma ilocanum
- Adult
➢ Oral sucker is at the center of the body; ventral sucker is located at the anterior fifth of the body a
Echinostoma ilocanum
- Adult
➢ Testes: lobate; located posterior to ovary
Echinostoma ilocanum
- Adult
➢ Ovary: globular; located anterior to the testes
Echinostoma ilocanum
- Adult
➢ Uterus: looped, anterior the ovary
Echinostoma ilocanum
- Adult
➢ Vitellaria: with small follicles which fills the lateral border of the posterior two-thirds of the worm
Echinostoma ilocanum
- Adult
➢ It is an elongate, piriform worm, with a broadly rounded posterior end and a more attenuate anterior end
Heterophyes heterophyes
- Adult
➢ Cuticle is covered with minute scale-like spine
Heterophyes heterophyes
- Adult
➢ Testes: ovoid and placed side by-side located at the posterior fifth of the body
Heterophyes heterophyes
- Adult
➢ Ovary: globular located anterior of the testes
Heterophyes heterophyes
- Adult
➢ Vitellaria: with large polygonal follicle in the lateral posterior third of the body
Heterophyes heterophyes
- Adult
➢ 1 mm to 2.5 mm by 0.4 mm to 0.75 mm in size
Metagonimus yokogawai
- Adult
➢ Slightly resembles H. heterophyes
Metagonimus yokogawai
- Adult
➢ Cuticle: covered with minute scale like spines
Metagonimus yokogawai
- Adult
➢ Ventral sucker: large, situated at the right side of the midline with its axis in a diagonal line
Metagonimus yokogawai
o Fasciolopsiasis
Fasciolopsis buski
o Most infections are light and asymptomatic
Fasciolopsis buski
o In heavier infections, symptoms may include diarrhea, abdominal pain, fever, ascites, anasarca, and intestinal obstruction
Fasciolopsis buski
o The patient may experience generalized toxic and allergic symptoms such as facial, abdominal walls, and lower limbs edema
Fasciolopsis buski
o Profound intoxication can result into death
Fasciolopsis buski
o Inflammatory lesions may develop at the sites of attachment to the intestinal wall together with a generalized toxic process
Echinostoma ilocanum
o Usual symptoms are intestinal colic and diarrhea
Echinostoma ilocanum
➢ The main symptoms are diarrhea and colicky abdominal pain.
Metagonimiasis
➢ Migration of the eggs to extraintestinal sites
(heart, brain) can occur, with resulting symptoms
Metagonimiasis
o Demonstration of eggs in the stool
Fasciolopsis buski
o Vomitous sample may be used for detection of eggs
Fasciolopsis buski
o NOTE: one should consider the resemblance between Fasciolopsis buski and Fasciola eggs
Fasciolopsis buski
Direct fecal smear examination
Echinostoma ilocanum
➢ Microscopic identification of eggs in the stool
Metagonimus yokogawai
➢ However, the eggs are indistinguishable from those of H. heterophyes and resemble those of Clonorchis and Opistorchis
Metagonimus yokogawai
➢ Specific diagnosis is based on identification of the adult fluke evacuated after antihelminthic therapy, or found at autopsy
Metagonimus yokogawai
- Since metacercaria are very sensitive to dryness, soaking of aquatic plants in water should be avoided
Fasciolopsis buski
- The time between harvest and consumption could also be prolonged to prevent infection
Fasciolopsis buski
- Washing of the plants to remove metacercaria or boiling them to kill the parasite can also prevent infection
Fasciolopsis buski
- Swamps or ponds, where aquatic plants are cultivated should be protected from pollution by untreated human or pig excreta
Fasciolopsis buski
- Community education
Fasciolopsis buski
- Eradication of snail intermediate hosts
Fasciolopsis buski
- Avoid eating raw aquatic plants
Fasciolopsis buski
Individuals can avoid infection by not eating raw snails in endemic areas
Echinostoma ilocanum
Praziquantel
Fasciolopsis buski
Echinostoma ilocanum
Metagonimus yokogawai
Lung fluke, Oriental Lung Fluke
Paragonimus westermani
METACERCARIA
Paragonimus westermani
Lung Pockets
Paragonimus westermani
▪ 1ST intermediate host: snail of genus Hua (Semisulcospira, Syncera and Thiara, Pomatiopsis, Pomacea, Brotia asperata – most common in the Philippines)
Paragonimus westermani
▪ 2nd intermediate host: Fresh water crabs or crayfish
Paragonimus westermani
- Ova/Eggs
➢ Operculated and ovoidal (80-120 um)
Paragonimus westermani
- Ova/ Eggs
➢ Yellowish-brown to dark or golden brown on color
Paragonimus westermani
- Ova/ Eggs
➢ Immature when laid with a germ cell and many yolk cells when oviposited
Paragonimus westermani
- Adult
➢ Reddish brown in color
Paragonimus westermani
- Adult
➢ Tegument is covered with single spaced spines
Paragonimus westermani
- Adult
➢ Active state: spoon-shaped with one end contracted and other end is elongated
Paragonimus westermani
- Adult
➢ Preserved state: oval, flattened, coffee bean shaped; has spinous cuticle and suckers of equal size
Paragonimus westermani
- Adult
✓ Females:
– ovary is lobed, located anterior to the testes on the right side opposite the coiled uterus
Paragonimus westermani
➢(?) – at the extreme lateral fields on the entire length of the body
Vitellaria
- Adult
✓ Males:
– irregular lobed testes are oblique to each other and located at the posterior third of the body
Paragonimus westermani
Paragonimiasis/Pulmonary Disturbances
Paragonimus westermani
➢ Patient with this disease most often complain of cough and hemoptysis, clinical manifestations are consistent with Pulmonary Tuberculosis (PTB). Hence, patients with this parasitic infection are often misdiagnosed with PTB.
Paragonimus westermani
✓ Chronic bronchitis
Paragonimus westermani
✓ Hemoptysis
Paragonimus westermani
✓ Abdominal pain
Paragonimus westermani
✓ Dry cough and later produces blood stained sputum with foul odor
Paragonimus westermani
✓ Chest pains, dyspnea
Paragonimus westermani
✓ Low grade fever, fatigue and generalized myalgia
Paragonimus westermani
o Definitive diagnosis is based on the detection of the characteristic eggs in sputum, stool, or less frequently, in aspirated material from abscessed or pleural effusion
Paragonimus westermani
o However, detection of eggs in sputum or feces of patients with paragonimiasis is often very difficult
Paragonimus westermani
o (?) – a typical finding is a ring-shadowed opacity, comprising several contiguous cavities that give the appearance of a bunch of grapes
X-ray
o Serologic methods (CFT, EIA, Immunoblot assay)
Paragonimus westermani
o Thorough cooking of crab meat
Paragonimus westermani
o Health education to change food habits of the population
Paragonimus westermani
o Praziquantel
Paragonimus westermani
o Bithionol
Paragonimus westermani
