Sushi Parasites & Fish Poisoning

1. Sushi Parasites & Fish Poisoning

2. Part 1Killer Sashimi

3. The Good

4. The Bad

5. Jejunum resected for acute abdomen one day after eating sashimi

6. Anisakiasis

7. Anisikid Nematodes Anisakis simplex (herring worm), and related worms Pseudoterranova spp. Contraceacum spp. • Most cases in Japan • 3 cases reported in San Francisco after eating sushi (1988) • By 1988, about 50 cases in US had been reported New England Journal of Medicine (319:1128-29, 1988

8. Gastric and Intestinal Anisakiasis • Larva in cross-section, burrowed into intestinal wall • Patient may feel tickling in throat & cough up worm • Anisakiasis most commonly affects stomach

9. Related HelminthNecator Americanus • Hookworm • Bloodsucker • Huge cause of anemia, decreased economic productivity, infertility. • Cost South Civil War?

10. Larvae of A.simplex Final hosts are dolphins & whales 1st intermediate host is krill 2nd host is fish/squid 150 spp. Acute gastric disease, occurs 1 to 2 h after eating raw fish Endoscopic removal is treatment of choice Occurs in sensitized individuals Anisakiasis

11. Intestinal Anisakiasis • Presents as Acute Abdomen • Confused with appendicitis, Chron’s, Gastrointestinal Cancer. • Diagnosis made after surgery • Extragastrointestinal involvement is possible • Omentum, liver, abdominal wall

12. My oh Moi!

13. Risky Fishes • Larvae occur frequently in: cod, haddock, fluke, pacific salmon, herring, flounder, and monkfish • Illuminating filets of fish (candling) mostly ineffective

16. Bilateral Hydro-pneumothorax • 21 yo M ate pickled crabs 3 weeks prior • Pleuritic chest pain and pink sputum • Paragonimiasis • Worm inflammatory response allows eggs to migrate into bronchus & sputum

17. Pulmonary manifestations of Paragonimus westermani • Ingested Paragoniumus metacercaria migrate to pleural cavity • Cause pneumothorax, pleural effusions • Common cause hemoptysis in SE Asia

18. TB or Parasite? • Cystic findings in lung • TB common in these locales. Misdiagnosis in 50% • Loffler syndrome - eosinophilic infiltrates migrate side to side

20. Soap bubble sign • Pt ate raw Japanese mitten crab • Paragonimuswestermani • Calcified “bubbly” frontal lobe lesion

21. Cerebral Paragonimus Disease • Encapsulated cerebral ova • In Japan, river crabs are placed next to raw fish • 2cm long, they carry P. miyazakii • Should not be eaten even if cooked!

25. Albuquerque Sushi Case • 40 yo male presents to ED at Albuquerque VA • He has passed a pale 1 meter long parasite • No symptoms • Only exposure to fish, he states, is homemade sushi made from salmon

27. Diphyllobothrium latum • Full grown worm from 1 to 15 meters! • Longest human tapeworm • Patient may vomit or pass worm • 2% symptomatic anemia • worm has affinity for vitamin B12

28. Freshwater & Andromous Fish • AKA Scandinavian or Jewish Housewife’s disease • Homemade Gefiltefish or Fish Balls • Absent Great Lakes • 1980 outbreak involved 4 physicians in LA, who ate salmon sushi (CDC)

29. Diphyllobothrium latum • Diagnosis: worm, operculate eggs in stool. • Adult may produce 1 million eggs per day. • Treat with Praziquantel or Niclosamide • Available from CDC

30. D. latum • Proglottid contain gravid uterus and several eggs. • Prevented by avoiding raw or pickled fish

31. Superficial larva migrans • 38 yo M who developed abdominal rash after eating firefly squid! • More commonly larva migrans appears after going barefoot in tropics Br J Derm Aug 1998(139) 2: 315 

32. Nematode larva Spirurina

33. FDA recommendations • All fish and shellfish intended for raw (or semiraw such as marinated or partly cooked) consumption be: • 1) Blast frozen to -35°C (-31°F) or below for 15 hours, • 2) Or, regularly frozen to -20°C (-4°F) or below for 7 days.

34. Part 2Now we’re cookin’

35. Grilled Walu (Yum!)

36. Ichthyosarcotoxism • AKA poisoning by fish flesh • Excludes shellfish poisoning • Excludes bacterially contaminated fish • Often misdiagnosed as gastroenteritis • A wide variety of fish are implicated

37. Ciguatera • Most prevalent Ichthyosarcotoxism • Over 400 fish species are implicated • Mainly large, carnivorous fish • Grouper, Snapper, Barracuda, Surgeon Fish, and Moray Eel.

38. CDC case report • 17 crew members of cargo ship fell ill in Freeport TX, in 1997 with nausea, weakness, and paresthesias • All had eaten barracuda - later found to be ciguatoxin positive • All recovered • 120 cases reported to CDC in decade prior in US

39. Crew Member’s Symptoms • Diarrhea (100%) • Abdominal Cramps (82%) • Nausea/Vomiting (76%) • Muscle Weakness (88%) • Itching/Numbness of mouth (65%) • Temperature reversal (65%) • Acroparesthesias (65%) • Dizziness (59%)

40. Ciguatera Clinical Features • Delayed Onset: 4-10 hours post ingestion • Initially: GI, nausea, vomiting, and diarrhea • Later: Neuro, paresthesias, temperature reversal – Hot objects feel cold on skin or in mouth • Heart block may occur

41. Ciguatera pathogenesis • Ciguatoxin is produced by dinoflagellate protozoan – Gambierdiscus toxicus • Reef fish can concentrate the toxin in flesh • Toxins are stable, resistant to cooking. • Ciguatoxin alters membrane properties of cells • Activates voltage dependent sodium channels in nerve and muscle

42. Ciguatera Treatment • Activated Charcoal • Supportive care • Correction of dehydration • Mannitol and Calcium have been reported to have benefits anecdotally • Neurologic symptoms may last months • Mortality is low < 1:1000

43. Ciguatera case report • Two Marshallese men (30 and 31 y.o.) developed circumoral numbness and tingling in fingers two hours after eating fresh-caught cooked snapper • 3 hours: burning sensation on drinking or touching water; marked weakness, then joint pains & lethargy. • 6 hours: unconscious, responded only to pain, with flaccid paralysis. JAMA, May 13, 1988 - Vol 259, No. 18

44. JAMA, May 13, 1988 - Vol 259, No. 18 • 72 hours: LR was given at a rate of 125 mL/h • 250 mL of 20% Mannitol solution administered IV at a rate of 500 mL/h while they were evacuated by aircraft. • One patient stood up ten minutes after mannitol therapy was started; the other patient, confused, sat up after five minutes. • Both discharged, fully recovered 48 hours after treatment.

45. Randomized Trial Mannitol • 50 patients: after 24 hours, 96% mannitol-treated patients vs. 92% saline-treated patients had improved (p = 1.0) • 12% and 24% of patients in each group were asymptomatic (p = 0.46). • Infusion pain: mannitol group (84%) > NS group (36%) (p = 0.0015). • Mannitol was not superior to NS in relieving symptoms and signs of CP but had more side effects. • Ciguatera fish poisoning: a double-blind randomized trial of mannitol therapy. Schnorf H - Neurology - 26-MAR-2002; 58(6): 873-80

46. Ciguatera Prevention • Avoid eating the biggest specimens of reef fish • Avoid eating scaleless fish (eels) • Avoid viscera – makes sense to me!

47. Probably this one’s ok

48. Fugu • Toxic Pufferfish • Known in sushi bars as Fugu • Fugu is prepared by specially trained chefs in Japan. • Several tens of cases each year in Japan • Mortality exceeds 50%!

49. Fugu/Tetrodotoxin poisoning • Most powerful emetic known • Causes severe GI upset with profound vomiting, pain. • GI symptoms are often accompanied by paresthesias, ataxia, respiratory depression. • Victims proceed to coma, convulsions, and death within hours

50. Tetrodotoxin • Axonal blocking agent, interferes with cytochrome system • Often causes bradycardia, heart block, circulatory failure, seizures, hypothermia. • Treatment is supportive, ICU, pressors, fluids, AC charcoal probably doesn’t hurt.