Transcript Marine Toxicology and Foodborne Poisoning

Marine
Poisoning and Envenomation
Jennifer Hughes
Dr. David Johnson
February 16, 2006
Le grand plan
• Marine envenomation
•
•
•
– Toxic animals that live in the ocean
– Mechanisms of envenomation
– Learn a little about venom
– Treatment
Marine poisoning
– Foods and food preparation to avoid
– Recognize the dangerous causes
– Learn a little about the toxins
Prepare for your next beach holiday
Not covering botulism, food poisoning
Poisoning vs Envenomation
• Marine envenomation
–
–
–
–
glands that produce venom
applied or injected parenterally
painful
CV effects
• Marine poisoning
–
–
–
–
animals accumulate toxins from environment
do not produce them
must ingest for toxic effect
GI and neuro clinical effects
Venom and Anti-venom
• “mosaic of antigens”
• Circulating and tissue-fixed
• Can be deeper than typical snake bites
• Circulating venom neutralized by specific
immunoglobulins (anti-venom)
• Anti-venom rarely reverses pathology at
site of envenomation
Marine Envenomations
• Worldwide 40,000-50,000 envenomations
each year
• Significant risk for swimmers in openwater athletic events
• Typically divide into vertebrates and
invertebrates
Stingray wounds are often
complicated by infections
with:
a.
b.
c.
d.
Staph aureus
Streptococcus
Vibrio vulnificans
Pasteurella multocida
Pain relief in Stonefish stings can be
provided by:
a.
b.
c.
d.
Peeing on the wound
Vinegar
Immersion in hot water
Scraping the wound with a
credit card
Anti-venoms exist for:
a.
b.
c.
d.
e.
Sea snakes
Sting rays
Stonefish
A and C
A and B
Vertebrates
• Stingrays
• Scorpaenidae (Stonefish, lionfish,
scorpionfish, tigerfish, zebrafish,
turkeyfish)
• Sea snakes
Stingrays
• 11 species in US coastal
•
•
•
•
•
waters
Burrow in shallow sand
Tail barb reflexively fires
Most common injury =
secondary bacterial infx
Venom =
phophodiesterase,
serotonin
HEAT LABILE
Stingrays
• Symptoms:
– Severe pain and burning locally
– Intensifies for several hours
– Systemic effects: muscle cramping, weakness, tremor,
syncope, cv collapse, seizures
• Fatality rare (chest injuries, bleeding, tetanus)
• Mx:
– Clean and debride wound, td proph, tx of infection
– Vibrio vulnificus (Ancef)
– Pain control by immersing in hot water (45 C)
Scorpaenidae (stonefish/lionfish)
• Scorpaenidae most common vertebrate to
sting humans
• Gulf of Mexico, Pacific and Indian Ocean
Stonefish
• Can be fatal!!
• Will attack humans if
•
•
•
threatened
Venom glands at tip of
spines
Verrucatoxin, nor-epi,
dopamine, tryptaphan
Stonustoxin (activates
nitric oxide pathway)
Stonefish
• Clinical signs and symptoms:
– Excrutiating pain (LOC)
– Induration, ecchymosis, hyperesthesia,
dyesthesia or anesthesia of affected limb
– N/V, diaphoresis, dyspnea, hypotension,
syncope
– Cardiac dysrhythmias, conduction abn,
ischemia, pulmonary edema, sz, paralysis
Lionfish
• Don’t normally attack
• Smaller venom glands
• Venom = PGE2,
•
•
Thromboxane B2,
PGF2
Severe burning and
swelling
Rare CV or neuro
effects
Treatment of All Scorpaenidae
• Soak limb in hot water
• Oral analgesic, local block
• Remove barbs/spines
• Excise blisters (full of venom)
• Tetanus
• Antibiotics
• ANTI-VENOM (usually used for stonefish)
Sea Snakes
• 50 species
• Pacific and Indian
•
•
•
Ocean
NONE in Atlantic or
Caribbean
All are toxic, seven
species fatal to
humans
Most bites harmless
 fangs too short!
Sea Snakes
• Venom:
– Peripheral neurotoxin
– Alters Na+, Cl- permeability without changing
Na-K-ATPase pump
• Symptoms occur with no local rxn
– 3-6 hrs cranial and peripheral neuropathies
– Paralysis, resp failure, myonecrosis,
myoglobinuria, renal failure
Management of Sea Snake bites
• Stabilize vitals
• Polyvalent sea snake
anti-venom
Invertebrates
• Jellyfish (box jellyfish, Portuguese man•
•
•
•
•
•
of-war)
Sponges
Cone shells
Octopi
Sea anenomes
Coral
Sea urchins
Quiz
A group of jellyfish traveling together is
called a:
a.
b.
c.
d.
School
Smuck
Fleet
Gaggle
Jellyfish
• Venom: bradykinin, serotonin, histamine,
PGs, adenosine, phosphodiesterase,
fibrinolysin, hemolysin…
• All have long tentacles hanging from
pneumatophore
• Venom injected by nematocysts
• Most result in local reaction, stinging,
ulceration, anaphylactoid rxn
What is a Nematocyst?
• Nematocyst = spring - loaded venom
gland that suddenly everts and delivers
venom
• Located on tentacles, spicules, etc
• Continue to fire after animal’s death
• May still be “loaded” when in skin
• Local reaction, allergic reaction, toxic
reaction (N/V/D, CP, cramps, SOB,
paralysis, cardiorespiratory collapse)
Portugese Man-of-War
• Florida
• July-Sept after tropical
•
•
•
storm
Excrutiating pain, welts,
myalgias, HA, resp
distress, CV collapse
multiple stings  death
Mx: ABCs, remove
tentacles, vinegar, credit
card scrape, NO
antivenom exists
Box jellyfish (sea wasp)
• Most deadly of all
•
•
•
•
•
stinging marine life
Australia, Southeast Asia
Enough venom to kill 10
adults
Fatality rate of 20%
Hypotension, muscle
spasm, resp paralysis,
cardiac arrest
Death can occur within
30 sec
Mx of Jellyfish envenomations
• INACTIVATE nematocysts (convince
someone to pee on you, vinegar)
• REMOVE tentacles and nematocysts by
shaving or scraping credit card
• Don’t use fresh water
• Td
• Antibiotic prophylaxis prn
• ANTI-VENOM for box jellyfish (Chironex)
Other invertebrates
• Fire coral
– nematocysts, local rxn
• Sponges
– inject venom with spicules  local rxn
• Cone shells
– snails inject venom through long tooth
– typically local rxn but can get CV collapse
• Blue-ringed octopus
– bites rare  tetrodotoxin
– mx supportive
• Sea urchin
– venom gland on spicule
– local rxn, embedded spine can be problematic
To sum it all up…
• Really bad (+/- fatal)
–
–
–
–
–
Stonefish (ANTIVENOM)
Sea snakes (ANTIVENOM)
Box jellyfish (ANTIVENOM)
Man-of-war jellyfish (with multiple stings)
Blue-ringed octopus
• Not quite as bad
–
–
–
–
Stingray
Many sea snakes
Lionfish
Corals, sponges, sea urchins, cone shells
To sum it all up…
Look but DON'T touch
Management
BITES
octopi
seasnakes
NEMATOCYSTS
jellyfish, sea wasp
man - of - war
STINGS
starfish, urchins
stingray, bonyfish
Local wound care
Antivenom for snakes
Remove tentacles
VINEGAR
Credit card scrape
Antivenom for sea wasps
Remove stinger
Irrigate
HOT WATER
Antivenom for stonefish
Thanks Rob!
Quiz
What is the definition of ichthyosarcotoxic?
a. Toxins causing pruritis as main symptom
b. Fish-borne toxins that specifically target
muscle of victim
c. Toxins from muscle, viscera and gonads of
fish
Marine Poisonings
• Affect voltage gated Na channels
• Myelinated and unmyelinated nerves
• Typically peripheral neuropathies
• Can get flaccid paralysis
Mr and Mrs Scuba
A young healthy couple on their honeymoon in
Nicauragua had a local dinner of rice, beans, a
large red snapper, canned fruit and wine.
Five hours after dinner, both developed abdo pain,
diarrhea, vomiting, then headache, numbness in
arms and legs, and bone and tooth pain. When
the woman reached for a hot washcloth to rub
on her “freezing skin”, the washcloth felt cold.
This sensation lasted for 3 days. Within 4 days,
their symptoms completely resolved.
Approach
• What did they eat?
• Where was it caught?
• If not eating, other activities?
• Pattern of neurological symptoms?
• Onset of symptoms?
• Can you make the diagnosis?
• Management?
Ciguatera Poisoning
• Most common fishborne poisoning
• Endemic to warm-water, bottom-dwelling
shore reef fish
• 35 degrees north – 35 degrees south
• MAY-AUGUST
• 500 fish species involved: barracuda, sea
bass, parrot fish, red snapper, grouper,
sturgeon
Ciguatera
• Dinoflagellates (plankton protozoa)
contain ciguatoxin
• Small fish eat dinoflagellates
• Bigger fish eat small fish
• Really big fish (>5 lbs) eat bigger fish
• People eat really big fish
• Ciguatoxin increasingly concentrated in
flesh, fat and viscera of larger fish
Ciguatoxin
•
•
•
•
•
•
Lipid soluble
Acid stable
Heat stable
Odorless/tasteless
Fresh and frozen fish
Prolonged opening of
voltage gated sodium
channels in nerves and
muscle tissues
Ciguatoxin signs and symptoms
• 2-6 hours after ingestion
• 75% within 12 hours
• 96% within 24 hours
• Clinical diagnosis
1. Gastrointestinal
– N/V/D
2. Neurological
–
–
–
–
–
Paresthesias, dysesthesias
Sensation of loose, painful teeth
Cold allodynia (pathognomic)
Ataxia
Vertigo, seizures, visual disturbances
3. Cardiovascular
– Bradycardia
– Hypotension
4. Diffuse Pain Syndromes
– Headache
– Myalgias
– Arthralgias
Natural History of Disease
• Mortality
– 0.5%
– Usually patients with comorbidities
• Duration of symptoms
– GI
• 24-48 hours
– Bradycardia & Neuropathy
• Days to weeks
Management
• Inducing vomiting likely unhelpful
• Supportive
• Activated charcoal (acc to Goldfrank)
• Cathartics
• IV Mannitol
Mannitol
• Though to decrease neuro and muscular
symptoms
– Evidence from
• Single cases
• case series
• Uncontrolled trials
• Non-randomized trials
• Animal studies
• RCT – N=50
Inclusion
• Consumed local reef fish
• Neurological and GI symptoms within 48 hours
Treatment
• Mannitol 20% - 500ml bolus
• NS – 500ml bolus
Primary Outcomes
1. Evolution of 13 items (5
point Likert scale) over 24
hours
•
•
Unvalidated scaleItems
GI symptoms
–
•
Neurological symptoms
–
•
Numbness, dysesthesia,
cold allodynia
Diffuse pain symdromes
–
•
N/V, diarrhea, cramping
myalgias, arthralgias, HA
Other
–
Pruritus, dizziness, general
weakness, dysuria
2. Evolution of
neurologic status at
baseline and 24 hours
Secondary Outcomes
1. Need for additional medication
-
acetaminophen, scopolamine, butylbromide,
promethazine, NS, atropine
2. Frequency of poor responders
–
–
–
Hospitalization >24 hours
Administration of open label mannitol
Rehospitalization
3. Subjective treatment satisfaction
Results
• Improvement of symptoms
– Mannitol - 96%
– NS - 92%
• p-value = 1.0
• Asymptomatic patients at 24 hours
– Mannitol -12%
– NS – 24%
• p-value 0.46
• Asymptomatic patients at 1 week follow up (70%)
– Mannitol – 28%
– NS – 28%
• Discomfort caused by treatment
– Mannitol - 84%
– NS – 36%
• p-value = 0.0015
Conclusions
• Mannitol equivalent to NS in relieving SSx
of ciguatera poisoning
• Mannitol has more side effects
• NS unlikely to have treatment effect, so
don’t use either
Treatment of Chronic Neurological
Effects of Ciguatera Poisoning
• Multiple case reports
– Gabapentin
– Amitryptilline
– Nifedipine
– Fluoxetine
– Tocainide
• No real evidence
Mr. Flush
54 yo M back from a week-long sport fishing trip in
Hawaii. He brought some fish back with him
(didn’t declare it to customs) and cooked some
up tonight for dinner washed down with several
glasses of Chilean wine.
15 minutes after eating, he developed burning in
his mouth, generalized pruritis, dysphagia,
headache, followed by vomiting and diarrhea.
On exam in the emergency department, his BP
was normal and his face and torso were bright
red.
Approach
• What did they eat?
• Where was it caught?
• If not eating, other activities?
• Pattern of neurological symptoms?
• Onset of symptoms?
• Can you make the diagnosis?
• Management?
Differential
• Anaphylaxis/anaphylactoid reaction
• Tyramine (wine, cheese)
• MSG
• Metabisulfites (wine, fruit, shrimp preserv)
• Tartrazine (yellow colouring food additive)
Scromboid poisoning
• Eating cooked, smoked, canned or raw
fish
• Mahi mahi and amber jack most common
(CDC)
• PREVENTABLE
Remember scromboid = histamine
• Histidine found in dark meat
• Morganella morganii, E.Coli, Klebsiella pneumoniae
•
•
•
•
•
•
contain histidine decarboxylase enzyme
Converts histidine to histamine and saurine in WARM
fish
Healthy fish < 0.1 mg/100 g of fish
12 hours at room temp = 100mg/100g of fish
Toxic = 50 mg/100g
Normal appearance, taste and smell
Rarely “honeycombing” and peppery taste
What Scromboid looks like
• Symptoms begin in minutes to hours
• Numbness, tingling, burning of mouth
• Dysphagia
• Flush (face, neck, torso)
• GI symptoms
• Rare: pruritis, angioedema, bronchospasm
Management
•
•
•
•
•
•
Activated charcoal
Supportive (fluids)
Antihistamines
H2 receptor antagonist*
B2 adrenergics/epi
Excellent prognosis
Blasely ML. Scombroid poisoning: prompt resolution of symptoms with cimetidine. Ann Emerg Med
1983, 12: 104-106.
Ms. Oy
A 23 yo female eats out at an local oyster
bar in Charlottetown in celebration of
finishing university for the summer.
Later that evening she starts vomiting. 2
days later her friends notice that she is
not remembering simple things in their
conversation.
Approach
• What did they eat?
• Where was it caught?
• If not eating, other activities?
• Pattern of neurological symptoms?
• Onset of symptoms?
• Can you make the diagnosis?
• Management?
Shellfish poisoning
• Mollusks eat
•
•
dinoflagellates MayAugust
Oysters, clams,
mussels, scallops
3 categories:
– Paralytic shellfish
poisoning (PSP)
– Neurotoxic shellfish
poisoning (NSP)
– Amnestic shellfish
poisoning (ASP)
Paralytic Shellfish Poisoning (PSP)
• Onset 1 hour
• Saxitoxin : blocks
•
•
•
•
voltage gated sodium
channels
Dose-related toxin
Fatality from resp
failure
Mortality 6%
Mx: lavage,
supportive, intubation
•
•
•
•
•
•
Numbness
Sensation of floating
Ataxia
Muscle weakness
Cranial nerve
dysfunction
Paralysis
Neurotoxic Shellfish Poisoning (NSP)
• Onset mean 3 hours
• Brevetoxin (P.brevis)
• Just like ciguatera poisoning but
NO PARALYSIS
• Not fatal
• Mx: supportive, ? Ventolin (Goldfrank)
Amnestic Shellfish Poisoning (ASP)
• Onset mean 5 hours
• Domoic acid
• Only documented
•
•
•
outbreak Canada 1987
from mussels in PEI
Mortality 2%
10% longterm memory
loss, neuropathy
Mx: decontamination,
supportive
• Symptoms
– GI: N/V/D/cramps
– Neuro: MEMORY LOSS
(damage to amygdala and
hippocampus)
– sz, grimacing, chewing,
opthalmoplegia less common
– CV: hypotension and
arrythmias
Miss Fugu
A 23 yo F is teaching English in Japan. She
presents to the hospital complaining of sudden
onset of headache, numbness in her lips,
tongue, face and feet after eating Fugu, a local
delicacy.
When you check on her in 5 minutes, her mouth
has developed bullae, she is drooling, cannot
walk any longer, and is now in severe respiratory
distress.
Killer Fugu!
• Tetrodotoxin Poisoning
• Mortality 50% in some
•
•
•
•
studies
Only Tetraodontiformes
Order
Japan, California, Africa, SA,
Australia
100 species:globefish,
balloonfish, blowfish,
toadfish, blueringed
octupus.
2 newts in Oregon,
California and Alaska can be
fatal
Sims et al. Pufferfish poisoning: emergency diagnosis and management of mild
human tetrodotoxication. Ann Emerg Med 1986, 15: 1094-1098
Tetrodotoxin
• Found in liver, ovary,
•
•
•
•
intestines, skin
Heat stable
Water soluble
Dose-dependent
Inhibits Na-K pump
and blockade of
neuromuscular
transmission
Tetrodotoxication
• Onset within minutes
• Neuro: HA, diaphoresis, dysesthesias,
paresthesias (lips, tongue, face, fingers,
toes), dysphagia, weakness, ascending
paralysis in 2-4 hours
• Skin: Buccal bullae, salivation
• GI: N/V/abdo pain
• CV: hypotension
Clinical grading for tetrodotoxin
Diagnosis
• Clinical
• Tetrodotoxin detected in urine up to 5
days post-ingestion
• 24 hour urine collection
Management
• Decontamination (charcoal, GL, cathartic?)
• Airway protection
• Supportive
Summary of shellfish ingestion
Clam, muscles, oysters, scallops
Consider symptom/sign
presentation
Neurologic only
Paralytic
Shellfish
Poisoning
Neurologic +
GI
paresth,ataxia,
vertigo,no paralysis
memory loss
predominates
Neurotoxic
Poisoning
Amnestic Shellfish
Poisoning
Thanks Rob!
In summary
INGESTION OF FISH
What kind of fish?
Onset of symptoms?
Symptom pattern?
Large fish
Not tetrodotoxic fish
Onset w/i hours
GI + Neurologic
Large fish
Not tetrodotoxic
Onset w/i hours
? allergic rxn (flush etc)
Tetrodotoxic fish
(puffer, blow, etc)
Onset w/i minutes
Ascending paralysis,etc
CIGUATERA
SCOMBROID
Tetrodotoxin
Thanks Rob!
References
Isbister et al. Neurotoxic marine poisoning. Lancet Neurology 2005; 2: 219-28.
Schnorf, et al. Ciguatera fish poisoning: a double blind, randomized trial of mannitol therapy.
Neurology 2002; 58:873-880.
Sims et al. Pufferfish poisoning: emergency diagnosis and management of mild human
tetrodotoxication. Ann Emerg Med 1986, 15: 1094-1098
Tunik, M and L. Goldfrank. Food poisoning. In: Goldfrank’s toxicologic emergencies, seventh edition.
2002; pp.1085-1099.
Weisman R. Marine envenomations. In: Goldfrank’s toxicologic emergencies, seventh edition. 2002;
pp.1592-1598.