Roundworms

1. Roundworms Pathophysiology

2. Ascaris lumbricoides • largest nematode parasitizing the human intestine • most common human helminthic infection worldwide

3. MOT: ingestion of infective eggs Larval migration through the lungs Most common site: JEJUNUM

4. Case Ascaris Bolus

5. Ascariasis • Diagnosis: identification of eggs in the stool

6. ASCARIASIS • DOC:mebendazole blocks glucose uptake of the parasite

7. Enterobiaisis • Enterobius vermicularis • human pinworm • Adult females: 8 to 13 mm, adult male: 2 to 5 mm • Humans : only hosts

8. MOT: ingestion of eggs

9. Enterobiasis • most typical symptom nocturnal perianal pruritus • Ectopic enterobiasis

10. Enterobiasis • Diagnosis: microscopic identification of eggs • Scotch test • cellulose-tape slide test • (3 negative results) • Swube tubes

11. Pinworm Collector Tubes

12. Flashlight test: “cotton threads”

13. Enterobiasis • DOC: pyrantel pamoate.  -spastic paralysis of the worm

14. Trichinellosis (trichinosis) • Trichinellaspiralis • Worldwide • Most common in parts of Europe and the United States

15. MOT: ingestion of contaminated meat with encysted cyst

17. The nurse cell–Larvae complex • may persist for 6 months to several years before calcification and death occur.

18. trichinellosis (trichinosis), • Steroids • Albendazole: decreases ATP production in worms, causing energy depletion, immobilization, and death

19. Prevention • adequate cooking to kill the parasite. • If no trace of pink in fluid or flesh is found, these temperatures have been reached.

20. Freezing : • Salting, smoking, or drying the meat does not kill cysts.

21. Human hookworms • Ancylostoma duodenale: Old World hookworm • Necator americanus: New World hookworm • Ancylostoma braziliense: penetrate the human skin (causing cutaneous larva migrans), but do not develop any further

22. HOOKWORMS • second most common human helminthic infection • Worldwide distribution, mostly in areas with moist, warm climate

23. MOT: skin penetration by filariform larvae Veinsheart lungstracheaGIT oral and transmammary route

24. Hookworm Filariform Larvae

25. NECATOR ANCYLOSTOMA 4 ventral teeth pair of ventral semilunar, curved cutting plates

26. HOOKWORMS • Necator ingests 0.03 mL of blood per worm per day • Ancylostoma ingests 0.20 mL blood per worm per day.

27. HOOKWORMS • Ground itch: Necator -intensely pruritic, erythematous, or vesicular rash usually appears on the feet or hands • pneumonitis (Loefflerlike syndrome) manifested by cough, fever, and malaise.

28. HOOKWORMS • DIAGNOSIS: Microscopic identification of eggs in the stool Ancylostoma Necator

29. HOOKWORM • DOC: Albendazole, Mebendazole or pyrantel pamoate can also be used

30. Ancylostoma braziliensis(cutaneous larva migrans, creeping eruption) • tropical and subtropical countries • Gulf and southern Atlantic states. • primarily a hookworm of dogs and cats • can infect man and cause skin eruptions • larvae have a tendency to move around for 2 to 10 weeks

31. CREEPING LARVAE MIGRANS Pathognomonic: serpiginous tunnels

32. Dracunculus medinensis(Guinea worm; fiery serpent of the Israelites) • 50 million people • North, West and Central Afric • southwestern Asia • West Indies • northeastern South America

34. MOT: ingestion of contaminated water with copepod (larvae inside)

35. Copepod • Water fleas/ Cyclops

36. Dracunculiasis