5 Written questions
5 Matching questions
- D. dendriticum adults live in
- Common name for Paragonimus westermani
- D. dendriticum has how many I.H.? What are they
- Paragonimus westermani - how many species known to infect humans? 2. Adult resides where? 3. Hosts - anything unusual?
- Does not require aquatic habitat to complete life cycle
- a 1. 1 of 7 or more known species of Paragonimus that infect humans. 2. Adult resides in the lung 3. DH is many carnivorous animals. I.H is snail, then 2nd IH is freshwater crab and crayfish. Paratenic hosts possible if birds or small mammals eat crayfish or crabs
- b 2. 1ST I.H. = Snail. 2nd = Ant
- c lung fluke
- d D. dendriticum
- e bile duct
5 Multiple choice questions
- Adult in lung, eggs in sputum or swallowed and in feces. 2. eggs hatch to miracidium 3. miracidium in snail to sporocyst to redia to cercaria 4. spined cercaria with knob tails are released to invade 2nd I.H like crab or crayfish. 5. they encyst as metacercaria and 2nd I.h eats them. 6. excyst in duodenum of 2nd IH. 7. Juvenile penetrate the intestine and embed in abdominal wall. 8. we eat the 2ND IH 9. Juvi's reenter coelom, penetrate coelom and migrate to our lungs. 10. They find a mate, and form cyst in lungs. 11. mature into adults
- Asia, Africa, Central and South America. About 20 million people infected. Habitat is swift flowing streams and snail habitats.
- P. westermani.
- F. hepatica -except that there is no trauma to gut wall or liver parenchyma due to juvenile migration. You see a lot of biliary and liver damage -inflammation, fibrosis, hepatic degeneration, cirrhosis, bile duct distention/dysfunction
- Most are asymptomatic - look for eggs in feces. Treat with praziquantel, expensive, or benzimidazoles. Control is difficult because of crazy life cycle. - snails and ants hard to control. Have to keep tabs on your grazing times.
5 True/False questions
Pathology and Symptoms of P. westermani → Migration of juveniles through coelom to lungs doesn't cause much damage, unless certain special tissues are hit. But once they get into lungs they stimulate an inflammatory response that surrounds the pair in granular tissue - causing ulcers, bleeding, fibrosis. Eggs form granulomas. Symptoms are breathing difficulties, chronic cough, bloody sputum - and if juvis migrate to spinal cord or heart or brain they can cause paralysis, heart attack or death from granulomas.
Life cycle of D. dendriticum (probs the only important thing to know about it) → 1. Eggs in feces 2. (Cionella lubrica in U.S snail eats egg) 3. Miracidium in snail intestine to digestive gland 4. mother sporocyst to daughter sporocyst 5. no redia - to cercaria (tailed). 6. Cercaria accumulate in mantle cavity and irritation causes mucous building and slime balls 7. (Formica fusca ant eats slime ball and ingest cercaria) 8. Cercaria penetrate ant gut and encysts as metacercaria inside ant hemocoel 8. One cercaria migrates to subesophageal ganglion and becomes brainworm and alters ant behavior. Remains at grass tip and eaten 9. Ruminent eats ant and metacercaria excyst in duodenum, juveniles migrates to bile duct. Adults in bile duct produce eggs.
John and his gf went out and had crab at a sketchy restaurant and now he is having breathing difficulties, what could he have? → finds eggs in sputum or feces, biopsy, ELISA, x ray or CT. Can often be mistaken for tuberculosis, pneumonia, spirochaetosis in lungs, or tumors, encephalitis, hydatids in brains.
Paragonimus westermani - 1. acetabulum 2. sex 3. morphology 4. tegument 5. reproductive system → 1. Adults in DH live in lungs, pair up 2. Eggs in sputum or swallowed and passed in feces. 3. After at least 16 days in water miracidium hatches. 4. Thieridae snail is IH. 5. adult/egg/miracidium/sporocyst/redia/cercaria ( inside snail
Diagnosis of p. westermani - can often be mistaken for, in brain? → finds eggs in sputum or feces, biopsy, ELISA, x ray or CT. Can often be mistaken for tuberculosis, pneumonia, spirochaetosis in lungs, or tumors, encephalitis, hydatids in brains.