1. Phylum: Platyhelminthes class: Trematoda Schistosoma
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Phylum: Platyhelminthes class: Trematoda Schistosoma

2. Trematodes Schistosomes: Blood flukes
Family: Schistosomatidae Genus: Schistosoma Spp. : Schistosoma haematobium, Schistosoma mansoni, Schistosoma japonicum. For animals (ruminant & horses) : Sch. bovis, sch. Mattheei, sch. Spindale, sch. nasalis, Sch. margrebowiei Disease : Bilharziasis or Schistosomiasis

3. Sch. japonicum
Sch.mansoni
Sch. haematobium
Spp.
Oriental bilharziasis
Katayama disease(fever)
Intestinal bilharziasis
(schistosomiasis dysentery)
Urinary bilharziasis
(Vesical schistosomiasis), endemic haematuria
Name of disease
Human&domestic animals&wild rodent
Human& monkeys& rodents
human
Final host
Lung fibrosis,
spleenomegally
Liver fibrosis , bloody diarrhea
Hyperplasia & calcification of bladder
Clinical signs

4. Male adult worm :
S. haematobium S. mansoni S. japonicum
Length – 15 mm – 10 mm – 20 mm
Integument finely tuberculated coarsely tuberculated smooth
No of testes – 5 ( 4 ) – 9 ( 7 ) in (cluster) – 9 ( 7 ) (in column)
Ceca reunite late reunite early reunite very late
Female adult worm :
Length – 20 mm – 14 mm – 30 mm
Position of the ovary posterior half anterior half middle
Length of the uterus long short long
No. of ova in the uterus – – – 300
Ova :
Spine terminal spine lateral spine short lateral spine (rudimntary)
Present in urine, less, frequenitly in stool in stool rarely in urine in stool
Habitat in human :
Body vesical plexus of urinary bladder inferior mesentric vein, superior mesentric vein, less
less frequently superior frequently interior
Snails :
(intermediate host) Bulinus truncatus Biomphalaria spp Oncomelani spp.

5. Differential Features of Shistosoma spp.

6. Schistosoma japonicum Egg Schistosoma mansoni Egg
( in stool )
Schistosoma haematobium Egg
( in urine )
Schistosoma mansoni Egg
( in stool )

7. 5/11/2018

8. Schistosoma spp- Cercaria
Schistosoma spp- Miracidium

9. Oncomelania
Biomphalaria

11. Pathogenesis It belong to a kind of allergic reaction(rapid & delayed)
Formation of granuloma produced by eggs Concomitant immunity
Ectopic lesion (lung & brain)
"swimmer's itch", due to irritation at the point of entrance. The rash that may develop can mimic scabies and other types of rashes. Other symptoms can occur 2-10 weeks later and can include fever, aching, cough, diarrhea, or gland enlargement. These symptoms can also be related to avian schistosomiasis, which does not cause any further symptoms in humans.

12. Pathology
Schistosome eggs, which may become lodged within the hosts tissues, are the major cause of pathology in schistosomiasis. Some of the deposited eggs reach the outside environment by passing through the wall of the intestine; the rest are swept into the circulation and are filtered out in the periportal tracts of the liver, resulting in periportal fibrosis. Onset of egg laying in humans is sometimes associated with an onset of fever (Katayama fever). This "acute schistosomiasis" is not, however, as important as the chronic forms of the disease. For S. mansoni and S. japonicum, these are "intestinal" and "hepatic schistosomiasis", associated with formation of granulomas around trapped eggs lodged in the intestinal wall or in the liver, respectively. The hepatic form of the disease is the most important, granulomas here giving rise to fibrosis of the liver and hepatosplenomegaly in severe cases. Symptoms and signs depend on the number and location of eggs trapped in the tissues. Initially, the inflammatory reaction is readily reversible. In the latter stages of the disease, the pathology is associated with collagen deposition and fibrosis, resulting in organ damage that may be only partially reversible.

13. Pathology
In S. japonicum about two-thirds of eggs are not excreted, instead they build up in the gut. Chronic infection can lead to characteristic Symmer's fibrosis (also known as "clay pipe stem" fibroses, these occur due to intrahepatic portal vein calcification which assume the shape of a clay pipe in cross section). S. japonicum is the most pathogenic of the schistosoma species because it produces up to 3,000 eggs per day, ten times greater than that of S. mansoni.
5/11/2018

14. Clinical Manifestations
the migratory phase lasting from penetration to maturity,
(2) the acute phase which occurs when the schistosomes begin producing eggs,
(3) the chronic phase which occurs mainly in endemic areas

15. Acute Schistosomiasis
Clinical manifestations come out after 4 to 8 weeks of infection, similar to the time from egg to adult worm (40 days)
Fever: intermittent, maintain weeks to months
Allergic reaction: urticaria, angioneuroedema, enlargement of lymph nodes and eosinophilia
Digestive syndromes: abdominal pain, diarrhea with pus and blood, constipation or diarrhea
Hepatosplenomegaly.

16. Chronic Schistosomiasis
Asymptomatic: most person are asymptomatic
Symptomatic: the most common syndrome is abdominal pain with intermittent diarrhea.
hepatosplenomegaly

17. Terminal stage of schistosomiasis
Liver cirrhosis is the prominent syndrome of this stage
According to the manifestations , it can be divided into types:
The type of giant spleen
The type of ascites

18. Diagnosis
Epidemiologic date: occupation, history of travel to endemic area, contact with infected water
Clinical date:
Acute stage; chronic stage; terminal stage
Laboratory findings:
Blood Rt; characteristic eggs in feces; biopsy; positive immunological test

19. Treatment
Praziquantel is the best choice of drug for the therapy of schistosomiasis
Dose:
chronic schistosomiasis
10mg/kg, tid. for 2 days, total 60mg/kg
Acute schistosomiasis
10mg/kg,tid. for 4 days, total 120mg/kg