Schistosomiasis & fascioliosis.ppt

SchistosomiasisSchistosomiasis

Parasitology Dept.Parasitology Dept.

Human Blood FlukesHuman Blood FlukesSchistosomatidaeSchistosomatidae

Three main species that infect man:Three main species that infect man: Schistosoma japonicumSchistosoma japonicum (Africa, Middle East, (Africa, Middle East,

India)India) Schistosoma mansoniSchistosoma mansoni (Africa, Middle East, (Africa, Middle East,

Suthern America)Suthern America) Schistosoma haematobium Schistosoma haematobium (China, Japan, SEA)(China, Japan, SEA)Indonesia : Schistosoma japonicumIndonesia : Schistosoma japonicum

Four minor species that infect man:Four minor species that infect man: Schistosoma mekongiSchistosoma mekongi Schistosoma intercalatumSchistosoma intercalatum Schistosoma bovisSchistosoma bovis Schistosoma mattheiSchistosoma matthei

Human Blood FlukesHuman Blood FlukesSchistosomatidaeSchistosomatidae

Sexually dimorphicSexually dimorphic Male has Male has gynaecophoric canalgynaecophoric canal Egg is not operculatedEgg is not operculated Requires only one intermediate host (snail)Requires only one intermediate host (snail) Forked-tail cercaria (infective stage)Forked-tail cercaria (infective stage) Do not have encysted metacercariaDo not have encysted metacercaria Portal of entry: skin penetrationPortal of entry: skin penetration Adults do not multiplyAdults do not multiply

Schistosomatidae Schistosomatidae General CharacteristicsGeneral Characteristics

Blood flukesBlood flukes Anterior part contains 2 suckersAnterior part contains 2 suckers Requires 1 intermediate host (aquatic Requires 1 intermediate host (aquatic

snail)snail) Egg has no operculumEgg has no operculum Sexually dimorphic, male and female Sexually dimorphic, male and female

live together (male has live together (male has gynaecophoric gynaecophoric canal canal ))

Bifurcated tail cercaria (infective stage)Bifurcated tail cercaria (infective stage) Do not have encysted metacercariaDo not have encysted metacercaria Portal of entry: skin penetrationPortal of entry: skin penetration Adults do not multiplyAdults do not multiply

Schistosomatidae Schistosomatidae General CharacteristicsGeneral Characteristics

Schistosoma japonicumSchistosoma japonicumGeneralGeneral

Distributed in Far East Asia e.g. Japan, China, Distributed in Far East Asia e.g. Japan, China, Thailand, Philippine, Malaysia and IndonesiaThailand, Philippine, Malaysia and Indonesia

Causes schistosomiasis japonica, Causes schistosomiasis japonica, Katayama Katayama diseasedisease

Sexually dimorphicSexually dimorphic Habitat is Habitat is superior mesenteric veinsuperior mesenteric vein and and

branches of final hostbranches of final host Final host is humansFinal host is humans Reservoir hosts are other mammalsReservoir hosts are other mammals Intermediate host is Intermediate host is Onchomelania spp.Onchomelania spp. snail snail

Schistosoma japonicumSchistosoma japonicumMorphologyMorphology

Egg is short ovoid Egg is short ovoid and not and not operculated, has operculated, has lateral knoblateral knob, and , and contains miracidiumcontains miracidium

Bifucated tail Bifucated tail cercariacercaria

Schistosoma japonicumSchistosoma japonicumMorphologyMorphology

Male:Male: AboutAbout 15 mm long and broader than 15 mm long and broader than

the female, the body rolled ventrally to the female, the body rolled ventrally to form a groove, form a groove, canalis gynecophoruscanalis gynecophorus, , into which the female worm fitsinto which the female worm fits

There are about There are about 6-8 testes6-8 testes on the on the dorsal side behind the ventral suckerdorsal side behind the ventral sucker

Smooth body surfaceSmooth body surface

Schistosoma japonicumSchistosoma japonicumLife CycleLife Cycle

Eggs in the feces o/t final host hatches i/t Eggs in the feces o/t final host hatches i/t waterwatermiracidiummiracidium

Miracidium invades the Miracidium invades the OnchomelaniaOnchomelania sporocyst sporocyst rediae rediae cercariacercaria

Cercaria comes out o/t snail and infects a Cercaria comes out o/t snail and infects a final host by adhering to the body surface final host by adhering to the body surface w/ its suckers and penetrating the skinw/ its suckers and penetrating the skin

They move to the portal vein They move to the portal vein superior superior mesenteric veinmesenteric vein and develop into adults and develop into adults

SchistosomiasisSchistosomiasis

Parasitology Dept.Parasitology Dept.

TransmissionTransmission

Caused by person passing feces or urine Caused by person passing feces or urine (depending on species) containing eggs (depending on species) containing eggs into water which is used for bathing, into water which is used for bathing, washing clothes, fishing and washing clothes, fishing and agricultural, and recreational purposesagricultural, and recreational purposes

The egg which contains a fully-formed The egg which contains a fully-formed miracidium hatches out when the egg is miracidium hatches out when the egg is immersed in waterimmersed in water


The miracidium swims actively to The miracidium swims actively to penetrate an appropriate snail host penetrate an appropriate snail host and develop to become cercariae, and develop to become cercariae, the infective stage for manthe infective stage for man

The cercariae emerge from the snail The cercariae emerge from the snail mainly on exposure to light and mainly on exposure to light and infect man by penetrating the skininfect man by penetrating the skin


Caused by person passing feces or urine Caused by person passing feces or urine (depending on species) containing eggs (depending on species) containing eggs into water which is used for bathing, into water which is used for bathing, washing clothes, fishing and washing clothes, fishing and agricultural, and recreational purposesagricultural, and recreational purposes

The egg which contains a fully-formed The egg which contains a fully-formed miracidium hatches out when the egg is miracidium hatches out when the egg is immersed in waterimmersed in water

TransmissionTransmission The tail of cercariae is shed during The tail of cercariae is shed during

penetration and the parasite penetration and the parasite transformed into schistosomula inside transformed into schistosomula inside the host tissuesthe host tissues

It enters the systemic circulation and It enters the systemic circulation and then finds its way into the portal then finds its way into the portal circulationcirculation

Snail hosts :Snail hosts : Genus Genus Onchomelania - S. japonicumOnchomelania - S. japonicum GenusGenus Biomphalaria - S. mansoni Biomphalaria - S. mansoni Genus Genus Bulinus - S. haematobiumBulinus - S. haematobium

HabitatHabitat

Schistosoma japonicum Schistosoma japonicum and and Schistosoma mansoni Schistosoma mansoni mature in the mature in the mecenteric veins o/t portal circulationmecenteric veins o/t portal circulation

Schistosoma haematobiumSchistosoma haematobium generally generally remains in the systemic circulation remains in the systemic circulation and mature in the blood vessels of the and mature in the blood vessels of the uretric and vesical plexusuretric and vesical plexus

1.1. Cercariae invade skin, Cercariae invade skin, casting off its tailcasting off its tail

2.2. Enter the veinEnter the vein3.3. It is carried to the heartIt is carried to the heart4.4. Passes through the lung Passes through the lung

and returns to the heartand returns to the heart5.5. Via mesenteric artery it Via mesenteric artery it

reaches the intestinal wallreaches the intestinal wall6.6. It moves from capillaries It moves from capillaries

to venous branchesto venous branches7.7. Finally inhabits the portal Finally inhabits the portal

veinvein8.8. Some cercariae in the Some cercariae in the

lung penetrate diaphragm lung penetrate diaphragm and invade the liverand invade the liver

9.9. Enter the portal veinEnter the portal vein10.10. Mature adults release ova Mature adults release ova

to outside by destruction to outside by destruction o/t host intestinal mucosao/t host intestinal mucosa

Clinical AspectsClinical Aspects

Invasive stage:Invasive stage: Pruritic rash appear Pruritic rash appear

on parts o/t body on parts o/t body which have contact which have contact with water containing with water containing cercariaecercariae

Develops after 24 Develops after 24 after exposure and after exposure and may last for 2-3 daysmay last for 2-3 days

EosinofiliaEosinofilia


Acute stage:Acute stage: Katayama fever: severe immune reaction Katayama fever: severe immune reaction

to the products of young flukes and eggs, to the products of young flukes and eggs, occurs within 5-10 wks after infectionoccurs within 5-10 wks after infection

It takes a form of an acute illness with It takes a form of an acute illness with fever, malaise, weakness, weight loss, fever, malaise, weakness, weight loss, muscular and abdominal pain, vomiting, muscular and abdominal pain, vomiting, lymhadenopathy, hepatic and spleen lymhadenopathy, hepatic and spleen enlargementenlargement

Clinical AspectsClinical Aspects Chronic stage:Chronic stage:

In In S. japonicum S. japonicum and and S. mansoni S. mansoni infection, infection, gastrointestinal involvement appear first – gastrointestinal involvement appear first – diarrhea, abdominal pain and headache due to diarrhea, abdominal pain and headache due to production of eggsproduction of eggs

Formation of granulomata (colonic and rectal Formation of granulomata (colonic and rectal polyps), ulceration, thickening of bowel wall as polyps), ulceration, thickening of bowel wall as well as portal vessels – “clay pipe-stem fibrosis” well as portal vessels – “clay pipe-stem fibrosis” (Symmer’s fibrosis)(Symmer’s fibrosis)

As more eggs enter portal circulation, portal As more eggs enter portal circulation, portal hypertension develop –liver and spleen hypertension develop –liver and spleen enlargement, anemia, ascites, rupture of varicose enlargement, anemia, ascites, rupture of varicose veins, hemathemesis , melena veins, hemathemesis , melena death death


Schistosomiasis Schistosomiasis mansonimansoni: multiple : multiple strictures with multiple strictures with multiple polyps and much altered polyps and much altered mucosal patternmucosal pattern


Human liver showing Human liver showing pipe-stem fibrosis pipe-stem fibrosis (Symmer’s fibrosis)(Symmer’s fibrosis)

Intestinal lession in Intestinal lession in schistosomiasis japonicaschistosomiasis japonica

1.1. Adults in portal veinAdults in portal vein2.2. Migrate into small vessels Migrate into small vessels

and lay eggsand lay eggs3.3. Both mechanical stimulus Both mechanical stimulus

and toxin from eggs and toxin from eggs rupture the vessel, eggs rupture the vessel, eggs then enter surrounding then enter surrounding tissue to cause cellular tissue to cause cellular infiltration, papilloma infiltration, papilloma formation andformation and

4.4. Ulceration o/t intestine. Ulceration o/t intestine. Eggs appear in the Eggs appear in the intestinal cavity and are intestinal cavity and are egested outside w/ bloody egested outside w/ bloody diarrheadiarrhea

5.5. Eggs deposited in external Eggs deposited in external wall, stay there for long wall, stay there for long time and make a noduletime and make a nodule

6.6. Mesenteric toxin of eggsMesenteric toxin of eggs7.7. lymph nodes become lymph nodes become

swollen due to bacterial swollen due to bacterial infectioninfection


In In S. haematobiumS. haematobium infection: infection: the most common symptom is the most common symptom is

hematuria/proteinuriahematuria/proteinuria Inflammatory reaction and granuloma Inflammatory reaction and granuloma

formation in the bladder is also commonformation in the bladder is also common Calcified eggs causing damage to Calcified eggs causing damage to

urinary tracturinary tract Ureter becomes obstructedUreter becomes obstructed


Eggs that are Eggs that are swept along with swept along with the flow of blood the flow of blood into iliac vein and into iliac vein and enter the systemic enter the systemic circulation can circulation can appear in any appear in any tissue to form tissue to form granuloma, granuloma, fibrosis, eg. lung fibrosis, eg. lung lession, brainlession, brain

Pulmonary schistosomiasisPulmonary schistosomiasis

DiagnosisDiagnosis

Parasitological diagnosis by finding Parasitological diagnosis by finding eggs in feces or urineggs in feces or urin

Biopsy o/t rectum to find eggs by Biopsy o/t rectum to find eggs by colonoscopycolonoscopy

Immunodiagnostic test: ELISAImmunodiagnostic test: ELISA Radiology: calcification in bladderRadiology: calcification in bladder USG: pipe-stem fibrosisUSG: pipe-stem fibrosis

TreatmentTreatment

PraziquantelPraziquantel (drug of choice): high (drug of choice): high efficacy, low toxixity, short treatment efficacy, low toxixity, short treatment course, kills the worm therefore help course, kills the worm therefore help to reduce/stop egg productionto reduce/stop egg production S. mansoniS. mansoni: single oral dose 40 mg/kg: single oral dose 40 mg/kg S. haematobiumS. haematobium: single oral dose 40 : single oral dose 40

mg/kgmg/kg

TreatmentTreatment

Schistosoma japonicumSchistosoma japonicum : : Chronic stage: total dosage 60 mg/kg Chronic stage: total dosage 60 mg/kg

(children 70 mg/kg) in 2-3 divided doses (children 70 mg/kg) in 2-3 divided doses during 1 day or 6 divided doses over 2 during 1 day or 6 divided doses over 2 daysdays

Acute stage: total dose of 120 mg/kg Acute stage: total dose of 120 mg/kg (children 140 mg/kg) given over 4-6 (children 140 mg/kg) given over 4-6 daysdays

Human Liver flukeHuman Liver fluke

- Fasciola hepaticaFasciola hepatica- Fasciola giganticaFasciola gigantica- Opistorchis viverriniOpistorchis viverrini- Clonorchis sinensisClonorchis sinensis

Main species :Main species : Fasciola hepatica & Fasciola giganticaFasciola hepatica & Fasciola gigantica : :

widely distributed in Asia.widely distributed in Asia.

Fasciola hepaticaFasciola hepaticaGeneralGeneral

Family FasciolidaeFamily Fasciolidae Distributed entirely over Europe, Distributed entirely over Europe,

southeastern Africa, America continents, southeastern Africa, America continents, Oceania, and JapanOceania, and Japan

Final host: originally ruminants, Final host: originally ruminants, occasionally humansoccasionally humans

Required 2 intermediate host; 1Required 2 intermediate host; 1stst is fresh is fresh water snail (water snail (Lymnaea sppLymnaea spp.), 2.), 2ndnd is water is water plantsplants

Fasciola hepaticaFasciola hepaticaCharacteristicsCharacteristics

Adult: flat and leaf-like, 2-3 cm in Adult: flat and leaf-like, 2-3 cm in length, 1 cm in width, length, 1 cm in width, cephalic cone cephalic cone structurestructure in the anterior end in the anterior end

Complicated-branched intestineComplicated-branched intestine Branched testis, branched ovary, Branched testis, branched ovary,

coiled uteruscoiled uterus Vitelline gland has complicated Vitelline gland has complicated

branches, spread all over the lateral branches, spread all over the lateral bodybody



Fasciola hepaticaFasciola hepaticaEggsEggs

Egg is largest Egg is largest among those among those of Trematodesof Trematodes

Eggshell is Eggshell is thin, light thin, light yellow, yellow, operculatedoperculated

Contains egg Contains egg cellcell

Fasciola giganticaFasciola giganticaGeneralGeneral

Family FasciolidaeFamily Fasciolidae Distributed in Africa, southeast Distributed in Africa, southeast

Asia, Hawai, India, PakistanAsia, Hawai, India, Pakistan Life cycle resembles that of Life cycle resembles that of F. F.

hepaticahepatica

Fasciola giganticaFasciola giganticaCharacteristicsCharacteristics

Adult: large, thin, Adult: large, thin, and longand long

Cephalic cone is Cephalic cone is not very obviousnot very obvious

The internal The internal structure is similar structure is similar to the previous to the previous oneone

Egg is similar to Egg is similar to other Fasciolidaeother Fasciolidae

Fasciola giganticaFasciola giganticaCharacteristicsCharacteristics

Life cycleLife cycle

Clinical AspectsClinical Aspects Fever, chillFever, chill Epigastrial painEpigastrial pain Icteric Icteric Mild to severe diarrheaMild to severe diarrhea

Prognosis : good,except Prognosis : good,except for severe infection for severe infection

Severe infection :Severe infection : billiary duct : billiary duct : chronic fibrosis chronic fibrosis

DiagnosisDiagnosis Parasitological diagnosis by Parasitological diagnosis by

finding eggs / adult worms in finding eggs / adult worms in fecesfeces

Sometimes adult can be found in Sometimes adult can be found in vomitesvomites

TreatmentTreatment bithionol 0.03 gr for 18 daysbithionol 0.03 gr for 18 days

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Schistosomiasis & fascioliosis.ppt