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Parasitology. Classification:. Parasitology. Protozology. Helminthology. Entomology. Continue. Helminthology. Platyhelminthes (Flat worms). Nematohelminthes (Round worms). Trematoda (Flukes). Nematoda. Ceastoda (Tape worms). Trematodes of medical importance in our course.
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Classification: Parasitology Protozology Helminthology Entomology
Continue Helminthology Platyhelminthes (Flat worms) Nematohelminthes(Round worms) Trematoda(Flukes) Nematoda Ceastoda (Tape worms)
Trematodes of medical importance in our course Heterophyes heterophyes Fasciola hepatica & Fasciola gigantica Schistosoma haematobium & Schistosoma mansoni
Unlike trematodes • Schistosoma has only one intermediate host. • No reservoir. • Schistosoma eggs not operculated. • Forked tail cercaria. • Cylindrical worm. • It is the only trematode in which sex is separated while other trematodes are hermaphrodite.
Schistosomiasis • Most cases are a symptomatic. • Symptoms:- • Urinary Schistosomiasis haematouria (blood in urine). • Intestinal Schistosomiasis gastrointestinal bleeding. • General complications of chronic Schistosomiasis are due to the presence of Schistosoma eggs in tissues of spleen, gut wall or urinary bladder walls.
Continue • Egg inflammation granuloma fibrosis, hepatomegaly & portal hypertension • Portal hypertension speelnomegaly ascitis & oesophageal varicose. • S. haematobiumeggs in bladder walls fibrosis, increase the frequency of bacterial infections bladder carcinoma or sterility. No damage in hepatocytes
Continue • S. mansonieggs in bladder walls secrete proteolytic enzymes damage to the distal colon. • Mortality due to Schistosomiasis occur due to bleeding from ruptured oesophageal varicose which treated by injection of Sodium Valporate.
Diagnostic Stage * Schistosomahaematobium:- - Eggs found in urine of urinary Schistosomiasis patients. - Oval egg with terminal spine.
Diagnostic Stage * Schistosomamansoni:- - Eggs found in stool of intestinal Schistosomiasis patients. - Oval egg with lateral spine.
Infective Stage * Schistosomacercaria(forked tail). * Found in fresh water. * Penetrate the skin of human upon contact with water containing it.
Intermediate host • SchistosomahaematobiumBulinustruncatus • SchistosomamansoniBiomphlariaalexandria
Drugs used in elimination of worms(Praziquantel) • It is drug of choice for all Trematodes & Cestodesexcept Fasciola species & hydated sand. • The nervous system of Trematodes and Cestodes is not completely studied. However Praziquantel was found to increase the calcium ion influx inside the worm muscle causing prolonged spasms for the worm; leading to spastic paralysis & death of the worm. • This action not observed on Nematodes, insects or mammalians.
Continue • Praziquantel is very safe, taken as a single or divided dose according to the worm type. • Dose is calculated according to the patient weight. • Praziquantel is swallowed, not chewed; as it is very bitter in taste.
Continue • Praziquantel is very safe, taken as a single or divided dose according to the worm type. • Dose is calculated according to the patient weight. • Praziquantel is swallowed, not chewed; as it is very bitter in taste.