DIPHYLLOBOTHRIUM LATUM parasitic infection .pptx

Medical Parasitology

1. Diphyllobothrium latum By Dr. Samar Sayed Professor of Medical Parasitology

2. Diphyllobothrium latum (fish tape worm) Present in lake regions in Europe & Japan Not recorded in Egypt but infection may be transported by imported fish

3. Mode of infection & infective stage Sparganum Diagnostic stage 1 st intermediate host 2nd intermediate host Infective stage

4. Life cycle D.H Man R.H. Fish eating animals Habitat Small intestine Diagnostic stage Egg in stool (70x50u,oval, operculated, thick shell, yellowish brown, contains immature ovum)  water In fresh water, egg  coracidium (ciliated hexacanth onchosphere )  swallowed by 1 st I.H.

5. 1 st I.H. Cyclops = Diaptomus= water flea Inside Cyclops, onchosphere penetrates intestinal wall to reach body cavity & becomes a procercoid larva (the 1 st larval stage). It is solid, elongated with spherical caudal end containing 6 hooks. Cyclops is eaten by the 2 nd I.H. 2 nd I.H. Fresh water fish as Salmon & Trout Procercoid larva reaches muscles where it develops into plercercoid larva or sparganum which is the infective stage

6. Infective stage plercercoid larva : solid, elongated, has an anterior invaginated scolex & striated cuticle Mode of infection Ingestion of raw or undercooked or undersalted fish containing plerocercoid larva In the intestine, larva becomes attached to intestinal wall  mature adult  eggs appear in stool after 6 weeks

7. Pathogenesis and clinical picture Abdominal pain and GIT disturbances Large number of worms intestinal obstruction Worm toxic by products  neulologic manifestations as headache, insomnia & convulsions Pernicious anemia (macrocytic hyperchromic )as the worm consumes vitamin B12 and secretes toxins

8. Diagnosis Stool examination to detect eggs or segments Blood examination anemia

9. Treatment Praziquentel is the drug of choice Prevention and control Treatment of infected cases Periodic de-worming of reservoir hosts Proper cooking of fish

10. Dr. Samar Sayed [email protected] 01091229986 Thank you