Marine Envenomation (Main)

Other Names

• Jellyfish sting

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Background

• This page refers to all marine envenomations
• Venomous aquatic animals are hazardous to swimmers, surfers, divers, fishermen and any other marine water sport

Epidemiology

• United States exposures
  • Jellyfish (31%),
  • Stingrays (16%)
  • Venomous fish venomous fish (including lionfish, catfish, and others) (28%)
  • Gastropods (6%)
• 1,500 sting ray bites annually in United States
• World wide
  • Thousands of injuries but few fatalities

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General

• Occurs primarily in tropical and equitorial bodies of water
  • Indopacific is most common for venomous species
• Most envonmenations occur not as an attack but act of self defense when animal perceives danger
• Over 100000, 100 of which are known to be poisonous (need citation)
• Marine venoms are generally contain heat labile proteins which quickly denature with hot water
• Always consider
  • Tetanus booster
  • Antibiotic prophylaxis (staph, strep, vibrio)
  • Always involve poison control if suspected toxicologic source (800-222-1222)
• Think local and be familiar with what you can expect to see in your region
• The vast majority of encounters are benign and just require reassurance
• When in doubt, use warm water
• No rule for micturition in any clinical setting
  • "The only time urinating on some one is indicated is between two consenting adults who are in to that sort of thing” - Dr Andrew Schmidt

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Risk Factors

• Swimmers
• Surfers
• Divers
• Snorkling
• Fishermen

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Differential Diagnosis

Water Related Injuries

• Hypothermia
• Immersion Pulmonary Edema
• Marine Envenomation
• Diving Emergencies
• Drowning
• Near Drowning

Envenomations and Mimics

• Marine Envenomations
  • Toxins (ciguatera, neurotoxic shellfish poisoning, paralytic shellfish poisoning, scombroid, tetrodotoxin
  • Stingers (stingray injury
  • Venomous fish (catfish, zebrafish, scorpion fish, stonefish, cone shells, lionfish, sea urchins)
  • Nematocysts (coral reef, fire coral, box jellyfish, sea wasp, portuguese man-of-war, sea anemones)
  • Phylum porifera (sponges)
  • Bites (alligator/crocodile, octopus, shark)
• Other
  • Anaphylaxis
  • Serum Sickness
  • Allergic Reaction

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Nematocysts

General

• Nematocysts are classified by the mechanism by which they inject their toxin
• Cnidaria is the phylum under the animal kingdom
• Generally, the treatment for these envenomations is inactivation of the toxin with 5% acetic acid (vinegar)

Seabather's Eruption

• Not specific, due to exposure to nematocysts
• Symptoms
  • Pruritic papules resembling insect bites in distribution of swim suit
  • Often occurs during a shower after swimming in ocean as fresh water ruptures larvae
• Treatment
  • Treat skin with acetic acid 5%, or lidocaine-containing first aid remedy
  • Wash swim suit with hot water and detergent, then machine or sun dry

Sea Nettle

• Taxonomy: Chrysaora specie
• Location: West coast USA, SW Europe Atlantic Coast, Mediterranean

Man-Of-War

• Taxonomy & Description
  • Physalia physalis, Physalia utriculus, AKA Blue Bottle
  • Location: found in Atlantic, Indian and Pacific oceans, including southern US
  • Not a true jellyfish
  • Formed by colonies of siphonophore with each unit a specialized animal of the same species
  • Underwater tentacles up to 30m (atlantic), 3m (pacific)
• Symptoms
  • Local sharp pain immediately after the sting, followed by an erythematous maculopapular linear rash, local edema, and numbness
  • Rash improves at 24 hours, complete resolution by 72 hours
  • Complications: Skin necrosis, cardiorespiratory collapse, and rarely death
• Treatment
  • Antivenom: None
  • Remove tentacles, preferably with forceps or gloved hand
  • Hot water (45°C) immersion for 10–20 min preferred over local application of ice-packs for pain control
  • Avoid using vinegar or methylated spirits (can increase nematocyst firing)
  • Topical anesthetics can be considered after successful removal of all tentacle fragments.
  • Use oral or parenteral analgesics if pain persists

Fire Coral

• Taxonomy & Description
  • Many species found worldwide on reef crests and in shallow waters (except Hawaii)
• Symptoms
  • Symptoms: immediate pain and urticaria, sometimes progressing to hemorrhagic or ulcerating lesions
  • Pain resolves by 90 minutes, local symptoms by 72 hours
  • Less commonly: severe systemic symptoms include nausea, vomiting, muscle cramps, dyspnea, anxiety, abdominal pain, and headache.
• Treatment
  • Apply acetic acid 5% (vinegar) to the skin.
  • Consider steroid cream or an oral antihistamine for symptomatic relief;
  • Consider oral corticosteroids if severe

Box Jellyfish

• Taxonomy & Description
  • Chironex fleckeri AKA sea wasp, marine stinger
  • Location: tropical indo-pacific, has been seen in southeast United States
• Sting
  • Timing: In Australia, 92% of the stings took place between October 1 and June 1
  • 83% were in shallow water (<1 m) between 3-6pm
  • Sting is a medical emergency, potentially lethal
  • Responsible for at least 67 deaths in Australia
  • Most people die 20 minutes after sting
• Symptoms
  • Initial: Itchy red maculopapular rash, burning pain, edema, and the classical ladder-rung pattern lesion
  • Major: Patient is altered, somnolent, bradypneic, tachycardic, hypotensive
  • Cardiotoxic effect, nerve palsy, hemolysis, cardiopulmonary decompensation, shock, and death
  • Up to 25% of people die, more than sharks
• Treatment
  • Antivenom: CSL Antivenom effective in first hour
  • Remove tentacles ASAP to reduce likelihood of lethal injury
  • Apply acetic acid 5% (vinegar) to the skin.
  • Hot water shower as tolerated for 10 - 20 minutes
  • Wound care: distal to proximal compression bandage shown to help in snake envenomations
  • Analgesia: ice, topical, oral, parenteral
  • Medications: consider verapamil (some evidence, need citation), beta blockers, magnesium sulfate

Iurkandji Jellyfih

• Taxonomy & Description
  • Carukia barnesi
  • Animal is small, 3 to 19 mm
  • Location: northern and western coasts of Australia
• Symptoms
  • Initially: wheal, local erythema at the sting site
• Irukandji Syndrome
  • Occurs 20m - 2hr after sting
  • Thought to be sympathetic nervous system stimulation.
  • Symptoms: severe abdominal, chest, limbs, or back pain; generalized muscular pain, hypertension, tachycardia, vomiting, nausea, diaphoresis, piloerection, and local erythema
  • Complications: Hypertensive crisis, hemodynamic decompensation with abnormal ECG and elevated troponins, cardiac failure, and death
• Treatment
  • Antivenom: none
  • Hot water shower as tolerated for 10–20 min
  • Vinegar irrigation
  • Antihypertensive therapy (phentolamine has been used)
  • Magnesium sulfate IV
  • Pain management (including local use of cold packs/ice and opiates)
  • Do not use pressure immobilization bandages

Sea Anemone

• Taxonomy & Description
  • Many species located in warm waters
  • tentacles loaded with stinging cnidocytes and secrete mucus that may contain cytolytic and hemolytic toxins, neurotoxins, cardiotoxins, and proteinase inhibitors.
• Symptoms
  • Initially; erythema and pruritus, petechiae, blisters, and ulceration
  • Rare: systemic reactions include fever, chills, malaise, weakness, nausea, vomiting, muscle spasm, and syncope
  • Most cases resolve within 48 hours
  • Severe reactions may become indolent, leading to hyperpigmentation, hypopigmentation, or keloid formation
• Treatment
  • Acetic acid 5%
  • Symptom management

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Stingers

General

• Apparatus that punctures skin, deliver venom
• Remove stinger, evaluate FB with XR or US
• Irrigate with hot water for 30-90 minutes
• Antivenom (stonefish)

Stingrays

• Taxonomy & Description
  • Family: Dasyatidae
  • Location: tropical warm waters and are found practically all over the world
  • Flat cartilaginous fish with caudal appendages harboring bilaterally retroserrate barbs and associated venom glands
• Mechanism of injury: 2 phase
  • Mechanical: due to barbed stinger at end of whiplike tail
  • Venomous: gland at the tail base is injected into the victim
  • Venom contains serotonin, 5’-nucleotidase, and phosphodiesterase
  • Toxin may induce peripheral vasoconstriction, bradycardia, tachycardia, atrioventricular block, and seizure activity
• Symptoms
  • Pain and laceration at puncture site, nausea, vomiting, muscle cramps, barb lodged in skin, pain and swelling
  • Peaks at 60 minutes lasting up to 48 hours.
• Complications
  • More typically seen if torso injury Hypotension, dysrhythmia, arterial lacerations, thorax, and spinal cord trauma
  • Also nausea, vomiting, muscle cramps, syncope, arrhythmias
  • Cause of death of the late Steve Irwin
• Treatment
  • Antivenom: none
  • Hot water immersion as tolerated, 30-90 minutes
  • Systemic and local analgesia
  • Plain films to evaluate for FB
  • FB removal- spine, if lodged in chest should be treated like torso laceration and removed in OR
  • If necrosis, area must be debrided
  • Prophylaxis with antibiotics

Spine Fish

Stone Fish

• Taxonomy & Description
  • Family: Scorpaenidae
  • Most venomous of the scorpion fish, venom comparable to potency of cobra venom
  • Resides in Indopacific ocean
  • 38 cm in length, 1.5 kg
  • Body covered in spines that release venom from mechanical pressure (i.e. someone steps on it)
• Symptoms
  • Severe pain and edema at site of sting, headaches, Severely painful cyanotic puncture, wound, necrotic ulceration
• Complications
  • Weakness, syncope, dyspnea, hypotension, and hallucinations, altered mentation, fever, nausea, vomiting, seizures, paralysis, heart block, heart failure, pulmonary edema, death can occur within 6 hours
• Treatment
  • Antivenom: CSL stonefish antivenom.
  • Remove all spines
  • Hot water immersion as tolerated 30-90 minutes
  • NSAIDs, local analgesia
  • Debridement if needed or deeply penetrated spine
  • Consider prophylaxis with antibiotics
  • Tetanus
  • Observe 6-12 hr

Lionfish and Scoprion Fish

• Taxonomy & Description
  • Family: Scorpaenidae
  • Location: coastal waters of the Atlantic Ocean (usually Brazil, Uruguay, and Argentina),
  • The scorpion fish remains an understudied fish due to its limited global distribution
  • Toxicity: Stonefish #1, Scorpion Fish #2, Lionfish #3
  • Common cat fish can also cause these symptoms and is statistically more common, although poison is much less severe
• Symptoms
  • Sharp, intense, throbbing pain at the site of injection which can radiate, peaks at 60-90 minutes
  • Mild: erythema, pallor, ecchymosis or even cyanosis are the first events that present, and result from the increased capillary permeability;
  • Moderate: vesicle formation, as an effect of the toxins;
  • Severe: local necrosis observed within days, which is considered a grave complication and requires debriding
• Treatment
  • Same as Stonefish
  • Antivenom: none

Sea Urchins

• Taxonomy & Description
  • Family: Echinodermata
  • Location: global distribution with many different species
  • Globular bodies covered by calcified spines either rounded at the tip or hollow and venom-bearing
  • Apparatus: toxin-coated spines
  • Various urchin venoms have been found to contain steroid glycosides, hemolysins, proteases, serotonin, and cholinergic substances
• Symptoms
  • Commonly a painful puncture wounds with severe local muscle aching lasting up to 24 hours.
  • Frequently, spines break off into the victim.
  • A spine in a joint can cause synovitis.
  • Systemic symptoms include nausea, vomiting, paresthesias, weakness, abdominal pain, syncope, hypotension, and respiratory distress. Secondary infections are common.
  • Chronic: granulomas may develop
• Treatment
  • Antivenom: none
  • Hot water (45°C) immersion
  • Wounds irrigated, superficial wounds can be explored
  • Spines “tattoo” the skin so you cant tell if they are out or not

Starfish

• Taxonomy & Description
  • Family: Echinodermata
  • Crown-of-thorns starfish (Acanthaster planci) most commonly cited
  • Venom is hemolytic, myonecrotic, hepatotoxic, and anticoagulant
• Symptoms
  • Puncture wounds with immediate pain, bleeding, and edema.
  • Wounds become dusky and tenosynovitis may develop.
  • Multiple punctures can cause systemic reactions with paresthesias, nausea, vomiting, lymphadenopathy, and paralysis.
  • Pain resolves in 30 minutes to 3 hours.
  • Retained spines can cause granulomas
• Treatment
  • Antivenom: none
  • Hot water (45°C) immersion
  • Wounds irrigated, explored

Cone Snails

• Taxonomy & Description
  • Conus geographus
  • Apparatus: venom gland, teeth at end of proboscis (nose)
  • Toxin: conotoxin or neurotoxin that acts as a neuromuscular blockade
  • Blocks potassium and sodium channels, then blocks calcium channels
• Symptoms
  • Symptoms: Severe pain at site of sting, muscular paralysis
  • Complications: palpebral ptosis, speech difficulty, and swallowing impairment, Respiratory arrest in 40 min to 5 h, duration 12 to 36 hours
  • 50 deaths reported in the literature with mortality rate 25%
• Treatment
  • Antivenom: none
  • Field management
    • Remove spine if possible to prevent further envenomation
    • Immobilize in hot water 40-45०C for 90 minutes or until pain relief
    • Monitor closely for any evidence of neuromuscular blockade and strongly consider intubation if present
  • Hospital management
    • Maintain ABCs
    • Consider edrophonium for paralysis
    • Consider narcan to reverse hypotension
    • Distal to proximal compression bandage

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Bites

Blue Ringed Octopus

• Taxonomy & Description
  • Hapalochlaena lunulata
  • Found in shallow waters throughout Indo-Pacific oceans
  • Injury typically occurs when picked up out of the water by humans
  • Toxicity: venom is tetrodotoxin which inhibits voltage gated sodium channels leading to paralysis
• Symptoms
  • Symptoms: Flaccid paralysis and hypotension
  • Complications: Respiratory failure and death
• Treatment
  • Antivenome: none
  • Potentially life threatening exposure
  • Supportive care including mechanical ventilation
  • Elevate affected limb with direct pressure to decrease to minimize spread
  • Complete recovery in 2-4 days

Lizard Bites

• Taxonomy & Description
  • Family: Helodermatidae
  • Mexican beared lizard found in Mexico and parts of Central America
  • Gila monster found in SE United States
  • Toxicity: venom delivered by bite, delivered by glands in lower jaw
  • Causes localized, rarely systemic effect
  • Note teeth can be left behind in wound as a foreign body and nidus for infection
• Symptoms
  • Local: crush and puncture wounds, local erythema and pain
  • Systemic: weakness, hypotension, diaphoresis
• Treatment
  • Antivenom: none
  • Remove animal
  • Imaging to identify FB, especially teeth
  • Irrigate copiously
  • Tetanus
  • Consider antibiotics

Sea Snakes

• Taxonomy & Description
  • Family: Hydrophiidae
  • Known to inhabit tropical Pacific and Indian oceans
  • Venom: peripheral neurotoxins acting at the acetylcholine receptor, and hemolytic and myotoxic compounds
  • Causes muscle necrosis, hemolysis, and renal tubular damage
  • Approximately 80% of bites do not result in envenomation due to small, easily dislodged fangs
• Symptoms
  • Initial painless pinhead-sized fang marks
    • Roughly 30-60 minutes later, muscle pain and stiffness, nausea, vomiting, ascending paralysis, respiratory failure, muscle necrosis, renal failure
• Treatment
  • Antivenom if any symptoms (Mortality rate 3% overall, 25% if not receiving antivenom)
  • Pressure immobilization
  • Maintain airway and breathing
  • Monitor electrolytes and urine output
  • Alkalinize urine if myoglobinuria (NaHCO3, diuretics)
  • Dialysis as needed for renal failure and hyperkalemia

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Other

Sponges

• General
  • Acellular attach to ocean floor
  • Carry silicon dioxide or calcium carbonate, dermal irritants crinotoxins [14]
  • Species: fire sponge (Tedania ignis), poison bun sponge (Fibularia nolitangere), an red moss sponge (Mammillaria prolifera)
• Symptoms:
  • Initial: edema, vesiculation, joint swelling, and stiffness typically resolve in 7 days
  • Extensive exposure: fever, chills, malaise, dizziness, nausea, muscle cramps, and formication.
  • Delayed systemic: erythema multiforme or dyshidrotic eczema can be seen
• Treatment
  • Remove spicules (adhesive tape, rubber cement, facial peel)
  • Apply 5% acetic acid (vinegar) soaks.
  • Steroid cream or an oral antihistamine may provide symptomatic relief.
  • Consider systemic corticosteroids for severe allergy, erythema multiforme, or dyshidrotic eczema.
  • Arrange wound checks because infections may develop requiring antibiotic therapy

Bristle Worm

• General
  • Covered with chitinous bristles that easily penetrate skin
• Symptoms
  • Painful urticarial rash last for 2 to 3 days and skin discoloration for up to 10 days
• Treatment
  • Remove bristles (adhesive tape, rubber cement, facial peel)
  • Acetic acid 5%

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Anaphylaxis

• Both the initial enevenomation and/or antivenom administration can lead to anaphylaxis
• Anaphylaxis definition:
  • Dermatologic symptoms + 2nd organ system (typically ENT, respiratory or GI)
  • Known allergen + hypotension
• Signs: hypotension, bronchospasm, facial and airway swelling, pruritus, urticaria, nausea, vomiting, and diarrhea
• Most occur within 15-30 minutes and resolve within 6 hours.
• Prevention
  • You can pre-treat with Diphenhydramine
  • Typically 50-100 mg IV in adults and 1 mg/kg in children
• Antivenom administration
  • Should be given no faster than one vial over 5 minutes
• If anaphylaxis develops
  • Standard treatment: Epinephrine, Corticosteroids, Antihistamines, symptomatic management and ABCs
  • Administer 0.1- to 0.2-mL aliquots of antivenom should be alternated with 0.03- to 0.1-mg IV doses of epinephrine,
  • Or an epinephrine drip administered, titrating to maintain heart rate less than 150 beats/min

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Serum Sickness

• Can occur secondary to antivenom administration
• Formation of IgG antibodies in response to antigens in antivenom causes deposition of immune complexes
  • Induces vascular permeability, activate complement, degranulate mast cells, and trigger release of proteolytic enzymes.
• Symptoms present within 8 to 24 days
  • Includes: fever, arthralgias, malaise, urticaria, lymphadenopathy, rashes, peripheral neuritis, and swollen joints.
• Management
  • Systemic Corticosteroids until symptoms resolve
  • Followed by 2-week taper
• Recommend consultation with specialist

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See Also

• Environmental (Main)
• Allergy and Immunology (Main)
• Dermatology (Main)

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