Metazoa >trematoda (flukes) Fasciola gigantica (liver fluke) Fasciola hepatica  (liver fluke) Heterophyes  heterophyes (intestinal fluke) Schistosoma haematobium (blood fluke) schistosoma mansoni (blood fluke)
distribution egypt europe egypt & turkey upper egypt delta
morphology size larger (leaf like) smaller *pear shape *3-suckers (oral ,ventral , genital) *genital system: (2-testes ,globular ovary ,vitelline glands) larger /fine cuticle smaller /coarse cuticle
LATERAL MARGINS parallel converging long uterus (10-20) /small vetelline short (one egg) /big vetelline
shoulders less prominent more prominent 3-5 testes big /posterior ovary 6-9 small /anterior ovary
intermediate host snail (Lymnaea cailliaudi) 2nd :water plants snail (Lymnaea trunctus 2nd >water plant 1-snail (pirenella conica) 2-fish Bulinus truncatus Biomphalaria alexandria
infective stage encysted metacercariae encysted metacercariae cercaria itself (not encysted)
source raw vegetables or water contain encysted metacercarias undercooked & undersalted fish (pickled <10 days) of Boury & Bolty fish water contaminated e circaria
disease Fascioliasis (liver rot) Heterophyiasis urinary bilharziasis intestinal bilharziasis
pathogensis 1-serious liver damage (due to pressure & toxic metabolites and feeding habits ) 2-worm in bile duct >inf >fibrotic changes >obstruction >liver cirrosis and general toxemia 3-migrating worms reach ectopic foci & form worm abscesses in diff parts of body 1-irritatn of intestinal mucosa 2-eosinophilia , intestinal discomfort  ,pain & diarrhea 2-eggs may enter circulatn >as emboli >lesions in diff parts eg myocarditis or H. failure ,brain hemorrhage 1-stage of invasion :irritatn +dermatitis 2-stg of migration :cercaria to lungs >he ,pneumonitis ,eosinophilia ,leucocytosis ,fever ,cough 3-stg of oviposition & tissue reaction :eggs in * tissue >pseudo-tubercle or bilharzial granuloma >fibrosis or calcificatn *other washed back >blood stream >ectopic lesions in diff parts of body *urinary bladder :(eggs) >hyperemia ,papular formn ,ulceratn ,thickened wall *urethra >obstructn *other pelvic organs >deposition of eggs (details) eggs deposit in mesentric plexus through wall of intestine to feces *eggs trapped in intestine wall >inf reaction >congestion ,ulceration ,sandy patches >wall thickened *dysentry e blood & mucous in feces *periportal fibrosis >portal hypertension (details)
diagnosis 1- characteristic egg in feces { diagnostic stage} >oval ,operculated ,thin shelled ,yellow ,contain immature larva  2-indirect (ultrasonography : IHA     , ,ELISA , CFT 3-by symptoms :fever ,chills ,vomiting ,dyspnea ,oesinophilia ,jaundice stool analysis >characteristic eggs (oval ,operculated ,thick shelled ,yellow in col (contain mature micacidium) 1-direct a:presence of egg in urine by sedimentatn in conical glass  (oval ,thin shelled with terminal spine ,translucent and contain miracidium) b:-Biopsy from blader mucosa using cystoscope 2-indirect a: IHA test for ab (titer =250) b:for ag :scistofast test (see details) not easy to diagnose 1-stool exam 2-rectal swap 3-rectal Biopsy (swap or bioxy test for ova) indirect :IHA test
treatment 1-Dichlorophenol (Bithionol) 30-50mg/kg for 10-15 doses 2-Triclabendazole "single dose" 3-surgical removal of ectopic flukes 4-dehydroemetine HCL 1- Bephenium bromide 2- Thiabendazole 3-praziquantel (Biltracide) 25mg/kg twice daily for one day praziquantel (Biltracide) >40mg/kg body wt as single oral dose 2-oxaminquine (for s.mansoni)  >single oral dose of 50 mg/kg ** Trinidazole is contraindicated for s.mansoni esp if liver fibrosis & portal hypertension
life cycle adult (in bile duct) >lie immature eggs in feces >in water miracidium develop w swim  to snail (24h') >change to sporocyst >rediae >cercarias (30days) >cercaria leave snail >encyst (infective stg) >intestine >peritonium >liver >bile duct (8 weeks) adult (in small intestine of man & fish) >egg in feces >water >ingested by snail (not hatch in water) >sporocyst >rediae >cercariae (30days) >leave snail >attack fish >encysted metacercariae (infective stg) >man >intestine adult (in pelvic and vesical plexus of veins) >immqture egg appear after 8 weeks of infectn >miracidium >snail >sporocyst (norediae) after 12 months >cercariae {infective stg} >max 48h in water >penetrate skin by contact e water or drinking through mucous membrane (e proteolytic enz) >venous circulatn >right heart and lung to systemic circulatn >adulted >paired >migrate to pelvic & vesical plexus (s.haematobium)
notes *hermaphrodite *2-hosts *falt unsegmented body ,bilaterally symmetric ** it cause increase in oesinophils n. (oesinophilia) is not diagnostic tool as parasite may occur e normal oesinophils ** False Fascioliasis (spurious infectn) (presence of Fasc eggs in feces of uninfected person due to ingestion of meat or liver of infected animal  >to confirm :patient not eat meat or liver for 3 days then repeat test mass control :1-avoid defecation in water 2-control of snails 3-examination of fishermen 4-proper cooking and salting of fish habitat :vesical and pelvic plexus ** host :exprimentally monkeys and rodents ** control :1-mass ttt 2-avoid defecatn in water 3-snail control by a-drynessb-periodic cleaning c-beatching canal banks e concrete or cuso4 habitat : mesentric venous plexus ( large intestine)** host :monkeys and rodents ** control as s.haemat.
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