TREMATODES

• TREMATODES OR FLUKES

  • nonsegmented, dorsoventrally flattened
  • bilaterally symmetrical
  • with digestive tract and 2 acetabula (ventral and anterior sucker)
  • heteroxenous
  • dioecious/monoecious
• TIPS ABOUT EGGS

  
  

  
  

  
  

  • embryonated = SHOC
  • unembryonated = PEFF
• LUNG FLUKES

  • 1st IH = snails, 2nd IH = crabs
  • hermaphroditic, heteroxenous
  • leaf-life, nonsegmented bodies
  • operculated eggs
  • infective stage = metacercaria
  • virulence = cysteine protease
  • excyst = stomach
• LUNG FLUKES

  Paragonimus westermani

  • Oriental Lung Fluke
  • 1st IH = Brotia (Antemelania) asperata, Antemelania dactylus
  • 2nd IH = Fresh water crabs (Sundathelphusa spp., Parathelphusa spp.)
  • Reservoir = Rats, dogs, cats; from stomach migrates to peritoneal cavity then reaches lungs
• LUNG FLUKES

  Paragonimus westermani = Eggs

  • broadly oval (thick, yellow brown shell)
  • flattened but prominent operculum)
  • abopercular thickening
  • with immature miracidium
• LUNG FLUKES

  Paragonimus westermani = Adults

  • Coffee bean shaped
  • ovoid with spiny tegument
  • round anteriorly and tapered posteriorly
  • ceca = zigzag fashion
  • lobed ovary
  • testes = irregularly lobed and found on each side
  • branched Vitellaria with finely granular Vitelline granules
• LUNG FLUKES

  Paragonimus westermani

  • Pulmonary inflammation
  • fever, chills, eosinophilia, chest pain
  • fibrosis -> pneumonia
  • eggs in lung tissue = extensive granulomatous reaction
  • TB-like cough (hemoptysis) = rust colored sputum; foul fish odor (diurnal)

  Diagnosis

  • 3% NaOH added to sputum to enhance
  • Best specimen = SPUTUM (eggs in bloody sputum); stool if sputum was swallowed
• LIFE CYCLE OF MAIN TREMATODES EXCEPT BLOOD FLUKES

  • (snail ) Miracidia -> sporocyst -> redia -> cercaria -> metacercaria (varies)
  • Cercaria = penetrates 2nd IH and encyst into metacercaria
• BLOOD FLUKES

  • 1 IH and 1 DH
  • non-hermaphroditic, most romantic, in copula
  • adult is cylindrical, dioecious
  • non-operculated eggs (contains develop miracidium)
  • cercaria penetrates skin -> swimmer's itch or schistosomal dermatitis
  • travels through mesenteric veins
  • males = curved ventrally (with gynecophoric groove = Schist)
  • females = long, slender, and body circular in section
  • with soluble antigens
  • nocturnal and causes serum sickness like
• BLOOD FLUKES

  Other Schistosomes

  • S. mekongi = from Mekong River, resemble japonicum but smaller
  • S. malayensis = found in peninsular Malaysia; resemble japonicum
  • S. intercalatum = acid fast (+) -> larger; with terminal spine and diamond body; found in feces
• BLOOD FLUKES

  Schistosoma mansoni

  • Manson's blood fluke (by Biomphalaria spp., Planorbis, Tropicorbis spp.) = SMALLEST blood fluke
  • from the rectum travels in inferior mesenteric vein of lower colon
  • Ova = light yellowish brown; with large lateral spine
  • Adult = tegument with coarse tuberculations; males = 8-9 testes; females = ovary (anterior), short uterus, 1-4 eggs
  • diseases = intestinal Bilharziasis; schistosomal dysentery
• BLOOD FLUKES

  Schistosoma japonicum

  • Oriental Blood Fluke (by Oncomelania quadrasi)
  • from the intestine travels in superior mesenteric veins
  • Ova = spherical and oval; small, pale-yellow; with small lateral spine
  • Adults = smooth tegument; males = 6-8 testes; females = ovary (median), long and well-developed, 50-100 eggs (many)
• BLOOD FLUKES

  Schistosoma japonicum

  • oriental schistosomiasis
  • Katayama's disease
  • hepatic and pulmonary cirrhosis
  • in world war 2 in Leyte, a lot of patients were Filipino and Americans, they acquired it from a river in Leyte where the battle took place.
  • Test = Circumoval Precipitin Test
• BLOOD FLUKES

  Schistosoma haematobium

  • Vesical Blood Fluke (by Bulinus, Physopsi, Biomphalaria)
  • migrates via hemorrhoidal veins to the venous plexuses of the urinary bladder then to the vesical, prostatic or uterine plexuses)
  • Ova = with large terminal spine
  • Adult = tegument with slight tuberculations; males = 4-5 testes; females = ovary (posterior), long uterus, 20-30 eggs
• BLOOD FLUKES

  Schistosoma haematobium

  • earliest symptom = hematuria
  • urinary Bilharziasis
  • schistosomal hematuria
  • increase eggs = hypertrophy of urothelium -> obstruction -> renal failure
  • chronic = pelvic pain, bladder colic
  • Specimen = 24-hour urine for ova detection
• BLOOD FLUKES LIFE CYCLE

  • embryonated egg -> miracidium (ciliated larva; at water) -> sporocyst (sac like ova; snail) -> cercaria (fork-tailed larva; infective and nocturnal) -> tail disappears -> Schistosomula (penetrates skin; at water) -> remains in subcutaneous tissue for 2 days; survive in serum/saline at 37C -> adults pair at the liver -> travels to the Mesenteric veins -> go to respective locations
• BLOOD FLUKES

  Test

  • Faust and Mekney's egg hatching tech
  • Circumoal precipitin test of oliver and gonzales = definitive/gold standard; serum + ova = (+) microprecipitate/blebs by Light microscope
• LIVER FLUKES

  • hermaphroditic
  • infective stage = metacercaria
• LIVER FLUKES

  Fasciola hepatica

  • Sheep Liver Fluke, Temperate Liver Fluke = largest
  • 1st IH = Lymnaea philippinensis, Succinea spp.
  • 2nd IH = Watercress (Nasturtium officinale), Kangkong (Ipomea obscura)
  • Reservoir = ruminants (liver and biliary passages in humans and mammals)
• LIVER FLUKES

  Fasciola hepatica = Eggs

  • large, ovoidal, yellowish brown
  • clear thin shell and small operculum
  • with immature miracidium
• LIVER FLUKES

  Fasciola hepatica = Adult

  • large, broad and flat body, leaf-like
  • with cephalic cone
  • branched internal structure
  • dendritic ovary and testes, short coiled uterus
  • diffusely branched Vitellaria, long and highly branched ceca
• LIVER FLUKES

  Fasciola gigantica

  • Tropical Liver Fluke, Giant Liver Fluke
  • longer, shoulders less developed
  • more branched ceca, longer branches of ovary
  • with larger egg
• LIVER FLUKES = Fasciolid

  • primary in sheep and goats

  Sheep Liver Rot

  • acute = larva migration in liver tissue -> necrotic lesions (fever, hepatomegaly, eosinophilia)
  • chronic = fasciola worms persistence in biliary ducts and causes fibrosis
  • Fasciolopsiasis = right upper quadrant abdominal pain, fever, and hypereosinophilia
  • Haizoun syndrome = suffocation due to attachment of adult worm in pharyngeal mucosa
  • induces Th1 and Th2 cytokines
• LIVER FLUKES

  Clonorchis sinensis

  • Chinese Liver Fluke, Oriental Liver Fluke
  • most important liver fluke in man
  • 1st IH = Alocinma spp., Bulimus spp., Parafossarulus spp., Semisulcospira spp.
  • 2nd IH = Cyprinoid fishes
  • Reservoir = fish-eating mammals
• LIVER FLUKES

  Clonorchis sinensis = Ova

  • broadly ovoidal and with thick rim around the operculum (shoulders)
  • with developed miracidium
  • yellowish brown, "old fashion electric bulb"
  • distinct convex operculum
  • median protuberance = abopercular knob
• LIVER FLUKES

  Clonorchis sinensis = Adult

  • resides in bile duct; flat and transparent body
  • attenuated anteriorly, rounded posteriorly
  • branched dendritic testes = tandem position
  • 3 slightly lobed ovary
  • granular vitellaria
• LIVER FLUKES

  Clonorchis sinensis = Clonochiasis

  • jaundice
  • diarrhea, anorexa, edema, eosinophilia
  • painful progressive hepatomegaly
  • cholangiocarcinoma = malignant tumor that arises from bile duct epithelium
  • pancreatitis
  • adenomatous tissue formation
  • diagnosis = eggs in stool
• LIVER FLUKES

  Opistorchis felineus

  • Cat Liver Fluke
  • 1st IH = Bithynia spp.
  • 2nd IH = Cyprinoid fishes
  • Reservoir = fish-eating mammals
• LIVER FLUKES

  Opistorchis felineus

  • Eggs = elongate ovoidal with tapering ends
  • Adult = resemble C. sinensis; unbranched ceca; lobate testes, lobed ovary; transverse vitellaria
• LIVER FLUKES

  Opistorchis felineus

  • same disease to Clonorchis
  • hepatitis-like symptoms, biliary tract obstruction, fibrosis, liver abscess, pancreatitis, suppurative cholangitis
  • also cholangiocarcinoma
  • diagnosis = eggs in stool
• LIVER FLUKES

  Nanophyetus salmincola

  • harbors Neorickettsia helminthoeca
  • causes salmon poisoning

  Philophthalmus = eye flukes
• INTESTINAL FLUKES

  Fasciolopsis buski

  • Giant Intestinal Fluke, Busk's Fluke
  • 1st IH = Segmentia spp., Hippeutis spp.
  • 2nd IH = Water caltrop, water chestnut, Bamboo shoots
  • Reservoir = pigs
• INTESTINAL FLUKES

  Fasciolopsis buski = Eggs

  • same as F. hepatica and F. gigantica (large)
  • with underdeveloped miracidium
  • with clear thin shell and small operculum
• INTESTINAL FLUKES

  Fasciolopsis buski = Adult

  • elongated, ovoid
  • cecae not branched
  • single, branched ovary
  • highly dendritic testes (in tandem)
  • finely granular vitellaria
• INTESTINAL FLUKES

  Fasciolopsis buski

  • ulceration of mucosa
  • interferes digestive juice secretion
  • abdominal pain
  • flatulence
  • generalized edema
  • diarrhea, nausea, vomiting
  • intestinal obstruction
  • intoxication due to absorption of worm metabolites
  • diagnostic = eggs in stool
• INTESTINAL FLUKES

  Fasciolopsis buski = Life Cycle

  • eggs -> miracidium (water) -> sporocyst -> cercaria (1st IH = snail) -> metacercaria (2nd IH = plant) = man
• INTESTINAL FLUKES

  Echinostoma ilocanum

  • Garrison's fluke
  • 1st IH = Gyraulus convexiusculus, Hippeutis umbilicalis
  • 2nd IH = Kuhol (Pila luzonica), Susong pampang (Vivipara angularis)
  • Reservoir = rats
• INTESTINAL FLUKES

  Echinostoma ilocanum = Ova

  • straw-colored, ovoid, operculated, matures in water (6-15 days)

  Adult

  • small, reddish-gray with 49-51 collar spines (horse shoe shaped), tapered at the posterior
  • unbranched ceca, lobed testes (in tandem), oval ovary
  • small follicles of vitellaria, ventral sucker at the anterior fifth of its body
• INTESTINAL FLUKES

  Echinostoma ilocanum

  • no symptoms
  • can cause some intestinal arthritis
  • inflammation, ulceration, intoxication
  • close relative = Artyfechinostomum malayanum
• INTESTINAL FLUKES

  Echinostoma ilocanum = Life Cycle

  • Egg -> Miracidium -> Redia (1st IH, snail) -> cercaria -> 2nd IH