AUTHOR AND EDITOR INFORMATION

Section 1 of 11  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Multimedia
• References

INTRODUCTION

Section 2 of 11  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Multimedia
• References

Background

Marine venoms have enormous diversity and complexity. Some venomous creatures, like the Cnidaria (formerly phylum Coelenterata), are extensively studied, partly because of the frequency and intensity of their interactions with humans.

Cnidaria, commonly known as jellyfish, form one phylum of aquatic invertebrates, made up of "true jellyfish" and other genera. These animals are responsible for more envenomations in the marine environment than animals of any other phylum, especially during warm summer months. Approximately 9,000 species of Cnidaria have been identified, and at least 100 pose risks to humans. Cnidarian envenomation produces a wide spectrum of syndromes in humans, ranging from minor local irritation to death. Although Cnidarian toxicity is not often correlated with morphology or tentacle size, it is correlated with bell size in Chironex envenomation.

The increase in reports of Cnidaria envenomation worldwide has been partly attributed to increasing human interaction during recreational water sports and during business in the marine environment. In addition, it may partly be attributed to the increase in temperature of the world's oceans over the last decade. As humans increasingly interact with this environment, so does the need for us to be aware of these creatures and of how to act if envenomation occurs to prevent both immediate and late complications.¹

Cnidaria are simple, radially symmetric animals that possess a gastrovascular cavity with a single opening that functions for both digestion and circulation. Cnidaria have 2 basic forms: sedentary, asexual hydroids or free-swimming, sexual medusans. This phylum contains approximately 11,000 species of simple animals found in aquatic environments. Cnidarians derive their names from the venom-bathed cnidocytes, specialized cells that possess stinging organelles.

Cnidaria are efficient predators that feed on crustaceans, other fish, and mollusks. The upper oral end of organisms from the class Hydrozoa or Anthozoa and the body margin of Medusan jellyfish contain stinging tentacles. The tentacles contain batteries of stinging cells (cnidocytes) that the organisms use to kill their prey by firing multiple, tiny, toxin-bathed stinging tubules (nema) out of specialized organoids called nematocytes. Nema introduce the toxin into the prey and activate other cells. Cnidarian toxins contain a complex mixture of proteins and polypeptides.

The phylum Cnidaria is taxonomically divided into 4 major classes, as follows:

1. Hydrozoa (Portuguese man-of-war, fire corals)
2. Scyphozoa (true jellyfish)
3. Cubozoa (4-tenticled [carybdeid], multitentacled box jellyfish [chirodropid]): Members of this class have a cube-shaped bell with 4 corners, each of which support 1-15 tentacles.
4. Anthozoa (sea anemones, soft corals [order Alcyonaria]), stony corals)

Fenner (1996) classified jellyfish into 3 major classes, as follows:²

1. Scyphozoa (true jellyfish), with tentacles arising at regular intervals around the entire bell
2. Cubozoa (box jellyfish), with tentacles arising at the corners
3. Other jellyfish, such as the Hydrozoa

The Portuguese man-of-war is a pelagic, free-swimming, colonial organism of the order Siphonophora (family Physaliidae) made up of 4 individual groups of Cnidarians. Several nematocyst-containing stinging tentacles hang from its floating sail (main body), which is 2-25 cm in length and is filled with nitrogen and carbon monoxide. This allows the colony to stay on the surface and enables its wind-assisted travel. Two species of Portuguese man-of-war are recognized. The larger species, Physalia physalis, lives in the Atlantic Ocean from Nova Scotia to the Caribbean Sea. However, a smaller version has been reported in north Australian waters. A smaller species of Physalia, Physalia utriculus, or the bluebottle, has a single fishing tentacle and is found in the Pacific Ocean and Indian Ocean.

Nearly transparent, the Atlantic man-of-war has tentacles that may extend 30 m (100 ft) and may contain millions of nematocysts. After a tentacle contacts an object, other tentacles may shorten to create loops and folds to increase the potential surface area for envenomation. Even detached tentacle fragments on the beach are hazards because they can release venom for months if they are kept moist or several weeks if they are air dried. Two confirmed deaths and cases of arrhythmia and renal failure caused by P physalis have been reported.³

Fire corals (Millepora species) are typically encountered off the coast of Florida and in the Caribbean. These white–to–yellow-green and, rarely, purple hydroid corals are sessile creatures that attach to rocks, coral, seaweed, or pilings. Unprotected, recreational scuba enthusiasts and snorkelers may handle, kneel on, or brush against these fire corals. Typical envenomation results in a mild local burning or stinging sensation, followed by pruritus and development of an edematous wheal. Hyperpigmentation may occur at the site, disappearing in 4 weeks. Pain sometimes radiates centrally, and painful regional lymphadenopathy may occur in response to multiple stings.

In the United States, the true jellyfish are the most common species that cause envenomation. Chrysaora and Cyanea sea nettles are located along the Atlantic coast, with a high concentration near the Chesapeake Bay. Of interest, in the coastal waters of eastern North American, jellyfish appear to become larger the farther north they are found. The largest species is the giant lion's mane (Cyanea capillata), the body of which can reach 3 m (10 ft) in the Arctic. Envenomations caused by scyphozoans are less severe than those caused by the Portuguese man-of-war.

The most toxic Cnidaria include chirodropid box jellyfish (the most important is the Chironex fleckeri, also called "the assassin's hand"),⁴ carybdeid jellyfish (including Carukia barnesi, which cause Irukandji syndrome), and the sea wasp (Chiropsalmus quadrigatus). These are among the most potent venomous marine creatures. These animals are found in northern Australian waters. Although these coelenterates do not naturally occur in American waters, a case of Irukandji envenomation was reported in the Gulf of Mexico in 2004. This was thought to be due to carybdeid jellyfish transported in the bilge water of an international ship.

Sea anemones are abundant, multicolored, flowerlike sessile creatures. Small children may accidentally ingest the tentacles. The anemones found in the United States tidal zones possess minimal toxicity. Corals are important components of living reefs, and the risk of infection from a cut caused by hard coral is of greater concern than its toxic effects. 

Pathophysiology

Most coelenterate venoms contain a complex mixture of proteins, carbohydrates, and polypeptides. These substances include histamines; catecholamines; hyaluronidases; fibrolysins; kinins; diverse ion channel–active neurotoxins; phospholipases; channel-active and pore-forming agents of the cellular membrane; and cardiotoxic, hemolytic, dermatonecrotic, and complement-activating agents.

The intensity of envenomation is related to both the coelenterate and to individual factors. Important variables include the season; the species and size of the animal; the number of nematocysts triggered; the size, age, and general health of the person; and the surface area and location of the sting.

The Cnidarian venom apparatus is fascinating. Cnidocytes are living cells present on the outer surface of the tentacles or near the mouth. Cnidocytes contain nonliving intracytoplasmic organoids called cnidae (nematocysts, sporocysts, p-mastigophore, or ptychocysts). The cnidae are contained within an outer capsule (cnidoblast) that is attached to a cnidocil, or trigger. The cnidae are filled with fluid and contain a hollow, coiled, 3- to 10-µm, sharply pointed, barb-lined, threaded tube (nema) that hold venom at the base of the cnidocil.

Rapid firing (£3 µs) of these nematocysts through a trap door under pressure (2-5 psi) occurs when the cnidocil is stimulated by change in osmolality, chemicals, or touch. The nema, which is estimated to be ejected at 2 m/s, penetrates the epidermis and dermis. Envenomation occurs as toxin is translocated by hydrostatic forces from the extended tubule through the hollow barbs. Muscular activity of the victim aids in venom circulation.

Cnidarian envenomations produce a burning sensation by unclear mechanisms. Activation of TRPV1, a nonselective cation channel in nociceptive neurons, has been shown to lead to depolarization of these neurons and pain. A recent study from Belgium, examined in vivo and in vitro effect of 4 species of Cnidarian venom (representing all 4 classes of Cnidaria) on TRPV1 activation.⁵ Cuypre et al reported desensitization-dependent activation of TRVP1 similar to that produced by Capsaicin, during Cnidarian envenomation. This suggests that TRPV1 is a key component in the signal-transduction pathway of Cnidarian envenomation. This information may allow for the design of more effective pain management modalities in Cnidarian envenomations.

Frequency

United States

Coelenterate envenomations occur in coastal areas of the United States, most often during the warm summer months, as a result of accidental or intentional interaction with these animals. The animals act on purely a physiologic and defensive basis. Envenomations by Scyphozoa organisms (true jellyfish) are the most common. Envenomations by Physalia organisms (Portuguese man-of-war) cause many swimmers and waders to visit emergency departments in Florida and Hawaii.

International

• Each summer, approximately 10,000 coelenterate envenomations occur off the eastern coast of Australia. Most patients with stings are treated at the beach and never require hospital treatment. Most patients in Australia seeking further medical care have severe pain but not systemic symptoms. The fatality rate following C flexeri envenomation is 15-20%; however, this probably represents a significant overestimation given the low number of documented fatalities in the setting of a large number of yearly stings.
• Mediterranean jellyfish (Rhopilema nomadica) envenomation rarely causes systemic symptoms. However, the population of these jellyfish, introduced to the Mediterranean with the opening of the Suez Canal in 1869, has steadily increased over the past 5 years.
• In Asia, an estimated 20-40 deaths occur each year in the Philippines from members of the Chirodropidae family. Approximately 2-3 deaths are reported annually in Malaysia from unreported species. Eight fatalities have been reported in the Yellow Sea off China due to Stomolophus nomurai  envenomation.
• Chirodropidae are found off the western coastline of Africa; however, no fatalities have been reported from this region.

Mortality/Morbidity

Fatal envenomations caused by the box jellyfish occur in tropical waters of northern Australia. At least 70 deaths have been documented.

CLINICAL

Section 3 of 11  

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History

• Reactions to coelenterate venom may be toxic or allergic. Reactions are usually presumed to be toxic rather than allergic because pain occurs immediately.
• Information surrounding the envenomation should be collected, including the time of envenomation, the nature of the incident, a description of the animal, and the timing and nature of the symptoms.
• Toxicity varies with the patient's age and underlying health, the potency of the venom, the number of nematocysts triggered, and the area of skin surface involved.
• Look carefully for skin lesions that might indicate envenomation in patients with unexplained near-drowning or in patients who collapsed in the water.

Physical

• The most common dermatologic presentation is a painful papular-urticarial eruption which often outlines the shape of the tentacles. Lesions can last minutes to hours, and the rash may progress to urticaria. 
• Other envenomations, including C barnesi envenomation, may initially be mild, with only a slight stinging sensation and minor redness at the envenomation site, followed later by significant systemic signs of envenomation. Still other envenomations, such as that of the larger C fleckeri species, may present with severe immediate linear and multiple purple-brown skin changes with transverse bars and massive wheals. These are shortly followed by erythema and vesiculation, which often last as long as 10 days and are followed by patches of dermonecrosis and permanent scars.
• Ocular contact has resulted in conjunctivitis, chemosis, corneal ulcerations, and lid edema.
• Mouth envenomation in children can produce considerable edema, and the patient's airway should be carefully and expectantly managed.
• Chronic reactions include keloid formation, hyperpigmentation, fatty atrophy, contraction, and vascular spasm. Uncommon local reactions include angioedema, recurrent reaction, contact dermatitis, and papular urticaria.
• Seabather's eruption is an erythematous, intensely pruritic rash consisting of wheals, vesicles, macules, and papules.⁶ This eruption develops on the neck, covers areas of the body approximately 24 hours after exposure, and may last 3-5 days. It is probably caused by the larvae of various organisms. Current reports center on the thimble jellyfish (Linuche unguiculata) and a sea anemone (Edwardsiella lineata). Previous sensitization may lead to reactions lasting as long as 6 weeks.
• Systemic reactions include headache, malaise, fever, nausea, vomiting, muscle spasm, pallor, respiratory distress, hemolysis, and acute renal failure.
• Ingestion of jellyfish can result in abdominal pain, cramping, and generalized urticaria.
• Irukandji syndrome consists of backache, arthralgias, myalgias, vomiting, sweating, pyrexia, tachycardia, dyspnea, and moderate-to-severe hypertension, with some reports of resultant pulmonary edema and intracranial hemorrhage. This syndrome may occur 10-40 minutes after envenomation by the small jellyfish (C barnesi). The syndrome has been attributed to toxin-induced catecholamine release. Although the systemic reaction can be clinically significant, the sting is frequently not visible.
• Hypersensitivity reactions may occur, but anaphylaxis is rare.
• The venom of the box jellyfish or sea wasp contains dermatonecrotic factors, which may involve the release of leukotrienes and other arachidonic acid metabolites and direct cell damage; a hemolytic factor, which may produce local hemorrhagic necrosis or ulceration at sting sites and may result in permanent scarring; and lethal factors that can induce respiratory and myocardial arrest.
• • Some researchers suggest that symptoms related to these stings may be partially immune mediated. 
  • Major envenomations may cover more than 50% of the body surface of one or more extremities. 
  • A tentacle print is rapidly seen secondary to venom components that release histamine from mast cells. 
  • More serious symptoms are likely if the Chironex bell is more than 15 cm wide. Neurologic and neuromuscular deficits include severe muscle cramping (particularly of the back musculature), seizures, spastic or flaccid paralysis, ataxia, vertigo, polyradiculitis, mononeuropathy, polyradiculitis, coma, and death. 
  • • Deaths within minutes have been reported.⁷
    • Death may be secondary to direct introduction of venom into the blood vessels. This hypothesis is supported by autopsy findings of nematocyst barbs that penetrated the vascular dermis. Deaths have been reported with as little as 4 m of tentacle marking.
    • Death most commonly occurs within 20 minutes after release of the venom and is attributed to hypotension, central respiratory paralysis, myocardial toxicity and cardiac arrest.
    • More than 60 deaths resulting from C fleckeri stings have been reported in northern Australia, 3 of which occurred despite timely intravenous administration of antivenom.
    • Deaths may also occur because people can drown after being incapacitated by the painful envenomation.

DIFFERENTIALS

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Other Problems to be Considered

Anaphylaxis
Echinoderm envenomations
Decompression Sickness
Lionfish or stonefish envenomation

WORKUP

Section 5 of 11  

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Lab Studies

• No specific laboratory studies are indicated for most envenomations.
• In severe envenomations, consider performing urinalysis and obtaining ABG; a CBC count; and levels of glucose, electrolytes, BUN, creatinine, and creatinine phosphokinase.

Imaging Studies

• In a patient with signs and symptoms of the Irukandji syndrome (eg, clinically significant blood pressure elevation, altered mental status or focal neurologic findings), CT scanning of the head is indicated to evaluate for intracranial hemorrhage.
• In a patient who is found unconscious or who had altered mental status in the water, plain chest radiography is indicated to evaluate for signs of aspiration and near-drowning. Plain chest radiography is also indicated in patients with Irukandji syndrome because pulmonary edema is a frequently reported constituent of the envenomation syndrome.

Histologic Findings

• Light microscopy examination of nematocysts, recovered from the victim's skin by scalpel blade scraping or sticky tape sampling, is used to identify the envenoming Cnidarian. 
• These tests exhibit good efficacy in retrieving usable nematocysts and specificity in their identification. 
• Unfortunately, in the case of the Irukandji syndrome, nematocyst identification rates remain low.

TREATMENT

Section 6 of 11  

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Medical Care

• Prehospital care
• • Witnesses may be helpful in removing the patient from the water and in initially decontaminating the patient.
  • Helpers and healthcare providers should be careful to avoid touching the coelenterate or its tentacles on the patient's skin with their bare hands to avoid becoming envenomated.
  • Lifeguards should be immediately notified of possible Chironex envenomation in Australia because rapid intravenous administration of antivenom is crucial in cases of serious envenomations.
  • Rinse the affected area with seawater. 
  • Inactivation of nematocysts should be guided by geographic location. 
  • In the southern United States, where Physalia species and Chrysaora quinquecirrha are of significant concern, animal studies showing increased venom release from active nematocysts with the application of vinegar suggest that vinegar should be avoided. 
  • In other parts of the world, especially the Indo-Pacific area, where C fleckeri and C barnesi are of significant concern, inactivate nematocysts with 5% acetic acid (vinegar). Once inactivation has occurred, remove any tentacles to prevent further injury. Avoid irrigating the wound with freshwater because it can stimulate the release of toxin.
  • If tentacles are present on the patient, they can be removed and saved for identification.
  • Use of a pressure-immobilization bandage to prevent the absorption of Chironex venom is controversial. Venom in Cnidarian envenomations may be widely distributed on the skin, and evidence suggests introduction of venom into the blood vessels rather than lymphatics. No animal studies have demonstrated beneficial effect of pressure immobilization bandaging in Cnidarian envenomations. As such, the efficacy of this modality remains, at best, unproven and, at worst, a potentially dangerous treatment. The Australian Resuscitation Council no longer recommends this modality in Cnidarian envenomation.
  • Capturing the organisms responsible for the envenomation is not necessary.
• Emergency department and ICU care
• • The severity of the injury directs treatment. Patients with severe systemic symptoms may require respiratory and cardiovascular support.
  • Reassure the patient.
  • Immobilize the envenomated area to minimize the uptake of venom.
  • Administer pain medications, as needed, to relieve pain. In significant envenomations repeated intravenous doses of narcotic pain medications, such as fentanyl, may be required to obtain relief.
  • Controlled clinical trials on the efficacy of heat or cold packs are limited. 
  • • In Australia, mild, painful stings have been found to respond well to ice pack application after the application of vinegar.
    • Hawaiian studies have found heat in the form of showers to be helpful in patients with Irukandji syndrome.⁸
    • A Hawaiian randomized, placebo-controlled trial of the analgesic effect of heat and cold packs in Carybdea alata envenomation showed a minimal trend towards pain relief after 10 minutes of the application of heat. Loten et al reported immersion of the limb in hot water (45ºC) to be effective in Physalia envenomation.⁹
  • Manage anaphylaxis with airway support, supplemental oxygenation, intravascular volume resuscitation, and epinephrine administration.
  • Verapamil is no longer recommended for cardiac therapy in patients with serious envenomation based on in vivo and in vitro evidence. Initially, verapamil had been anecdotally used in C fleckeri envenomation on the basis of experimental evidence that C fleckeri venom produced arterial constriction, bradycardia and reduced coronary blood flow. However, verapamil was associated with increased morbidity and mortality in an in vivo pig envenomation model. Theoretical reasons also argue against verapamil use in potentially unstable patients because it may cause cardiac dysrhythmias and potentiate hypotension.
  • An ovine antivenin (Commonwealth Serum Laboratories; Melbourne, Australia) specific for C fleckeri uses milked venom obtained by electrical stimulation of C fleckeri tentacles and has long formed part of the treatment of severe envenomation in Australia. 
  • • The antivenom neutralizes hemolytic, dermonecrotic, lethal, and pain-inducing effects of venom. However, evidence for its use in human envenomation remains anecdotal, with several reports of success but no controlled clinical trials. 
    • Survival of major envenomation despite the absence of antivenom has also been reported. 
    • The antivenom appears safe to use and is widely available in areas endemic for C fleckeri. 
    • Currently, antivenom is immediately administered as soon as first aid is applied.
    • It is currently indicated for all serious envenomations, including patients with intractable pain; those with difficulty breathing, speaking, or swallowing; and those with cardiopulmonary instability and cardiac arrest.
    • The recommended intravenous dose is 3 ampules (diluted 1:10) each given over 5 minutes; the intramuscular dose is 3 ampules.
  • Hypertension is universal in Irukandji syndrome and may be severe. 
  • • Catecholamine excess has been proposed as a significant mechanism for this hypertension because such phentolamine has long been used to treat this hypertension. 
    • More recently, given the propensity for cardiovascular collapse in these individuals, many centers familiar with these envenomations have moved to the use of more titratable agents with a shorter half-life, such as intravenous magnesium and nitroglycerin. 
    • Although no one treatment has demonstrated superior efficacy in controlled comparative trials, shorter-acting agents are preferred.
  • Pulmonary edema is also frequently reported in Irukandji syndrome. The mechanism of cardiac dysfunction remains to be elucidated. In some cases, it has been associated with elevated troponin levels, reduced cardiac output, and hypokinetic cardiac function on echocardiography. Effective treatment includes oxygen therapy, diuretics, vasodilators, inotropic support as needed, and mechanical ventilation or continuous positive airway pressure (CPAP).

Surgical Care

• Wound care is required.
• • The care provider should wear gloves to avoid envenomation by active nematocysts.
  • Gently irrigate the involved area with seawater or isotonic sodium chloride solution to wash off loose tentacles and nematocysts. Avoid irrigating the wound with freshwater because it can stimulate the release of toxin.
  • To prevent firing of remaining active nematocysts, neutralization should be performed. Diluted (5%) acetic acid is effective for neutralizing toxins of the Pacific box jellyfish (C fleckeri) and the Atlantic jellyfish but not the Portuguese man-of-war (P physalis) or C quinquecirrha. The application of topical papain is not effective, other than in treating seabather's eruption. Isopropyl alcohol is not recommended because it can cause the nematocysts of some jellyfish species to discharge.
  • In the case of corneal exposure, the application of acetic acid or other agents to the cornea is not recommended because this may worsen the injury. The patient should be referred to an ophthalmologist.
  • After the nematocysts are inactivated, carefully remove any visible tentacles with forceps.
  • Shaving cream may be applied to the wound, and any unseen nematocyst can be removed by scraping it with a knife or razor blade.
  • For removing unseen nematocysts, adhesive tape applied to the skin and removed may be just as effective as scraping with a knife or razor blade.
  • Baking soda may be effective for stings caused by sea nettles (C quinquecirrha).
  • A topical anesthetic ointment, antihistamine cream, or mild steroid lotion may soothe the skin. These are used after the toxin is inactivated and the tentacles and nematocysts are removed.
  • No animal or clinical data have identified any agent that reduces long-term scarring in Chironex envenomation. It is currently managed as a burn, with attention to avoidance of secondary infection. Indomethacin has been shown to reduce C fleckeri–induced capillary leakage.
• Prophylactic antibiotics are not automatically indicated. Wounds should be monitored for evidence infection.
• Standard antitetanus prophylaxis is indicated.

Consultations

• Local or regional poison control center personnel
• Medical toxicologist

MEDICATION

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Tetanus prophylaxis should be given. Antibiotics should be reserved for cases with evidence of true infection and should not be given prophylactically. Pruritus typically responds to antihistamines. Analgesics and local anesthetics may be used to ameliorate the pain associated with coelenterate bites. An antivenin for the box jellyfish (C fleckeri) produced in sheep is available in Australia.

Drug Category: Antivenin

Immediate protection of short duration may be achieved by means of passive immunization. This is accomplished by administering antibodies specific to the toxin, usually in the form of antisera.

Drug Category: Antihypertensive agents

Symptoms of Irukandji syndrome have been attributed to toxin-induced catecholamine release. Response to the alpha-adrenergic blocker phentolamine provides support for this theory. A protocol for treating patients with Irukandji envenomation was developed in Cairns, Australia.¹⁰

Other medical centers with experience dealing with severe Irukandji syndrome feel that an agent with a shorter half-life may be more advisable due to the potential for significant hypotension following initial hypertension. Glyceryl trinitrate has been effectively used as a titratable drip. As cases of echocardiographically proven cardiac dysfunction have occurred, hypotension must be avoided. 

FOLLOW-UP

Section 8 of 11  

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• Follow-up
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Further Inpatient Care

• Patients with severe envenomation may need inpatient treatment for pain relief, monitoring, and treatment of blood pressure or renal function and for supportive care.

Further Outpatient Care

• Patients should be warned that recurrent episodes of urticaria may occur at the site of envenomation for up to 4 weeks after contact.

Deterrence/Prevention

• The only absolutely reliable method of preventing exposure is to stay out of sea waters, especially during environmental conditions when Cnidaria are likely to be present.
• Other measures to avoid exposure include the use of "stinger suits" or other nematocyst-impermeable clothing and bathing inside stinger nets. Neither of these have proven foolproof, and certain small Cnidaria, including C barnesi, can easily penetrate these nets.

Complications

• Wound infection

Patient Education

• Numerous topical barriers have been tried and failed.
• • Ineffective agents include mineral oil, petrolatum, cocoa butter, and silicone ointment.
  • Current research is directed toward the development of a topical jellyfish-sting inhibitor.
• If jellyfish are present in the water, people should be advised not to swim in the vicinity and to maintain a safe distance away because of potential tentacle drift. Bathers should wear protective clothing, including stinger suits or double-thickness panty hose.
• • In Australian waters where Chironex species are present, bathers should be aware of areas of risk and stay within the jellyfish nets. However, small jellyfish, such as C barnesi, can slip through these nets. In areas where these jellyfish are a threat, people should stay out of the water during periods of likely infestation.
  • Individuals should be careful while walking on the beach in jellyfish infested areas without protective shoes. Children should be carefully educated not to place pieces of jellyfish or anemone in their mouths.
• If an individual receives a serious sting while in a body of water, they should be helped from the water because of the risk of drowning.

MISCELLANEOUS

Section 9 of 11  

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• Introduction
• Clinical
• Differentials
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• Treatment
• Medication
• Follow-up
• Miscellaneous
• Multimedia
• References

Medical/Legal Pitfalls

• Failure to recognize Cnidarian envenomation
• Failure to recognize that irrigation with freshwater may increase envenomation and pain associated with coelenterate envenomation
• Failure to recognize the need for tetanus prophylaxis

MULTIMEDIA

Section 10 of 11  

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• Multimedia
• References

Media file 1:  Close-up photograph of a sea anemone demonstrates tentacles surrounding the central mouth structures. Contact with tentacles results in the discharge of nematocysts. Courtesy of Scott A. Gallagher, MD.
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Media type:  Photo

Media file 2:  Close-up photograph of another sea anemone demonstrates the variability of tentacles among different species. Courtesy of Scott A. Gallagher, MD.
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REFERENCES

Section 11 of 11

• Authors and Editors
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1. Armoni M, Ohali M, Hay E. Severe dyspnea due to jellyfish envenomation. Pediatr Emerg Care. Apr 2003;19(2):84-6. [Medline].
2. Fenner P, Willamson J. Worldwide deaths and severe envenomations from jellyfish stings. Med J Aust. 1996;165:658-661. [Medline].
3. Stein MR, Marraccini JV, Rothschild NE, Burnett JW. Fatal Portuguese man-o'-war (Physalia physalis) envenomation. Ann Emerg Med. Mar 1989;18(3):312-5. [Medline].
4. Bailey PM, Bakker AJ, Seymour JE, Wilce JA. A functional comparison of the venom of three Australian jellyfish--Chironex fleckeri, Chiropsalmus sp., and Carybdea xaymacana--on cytosolic Ca2+, haemolysis and Artemia sp. lethality. Toxicon. Feb 2005;45(2):233-42. [Medline].
5. Cuypers E, Yanagihara A, Karlsson E, Tytgat J. Jellyfish and other cnidarian envenomations cause pain by affecting TRPV1 channels. FEBS Lett. Oct 16 2006;580(24):5728-32. [Medline].
6. Freudenthal AR, Joseph PR. Seabather's eruption. N Engl J Med. Aug 19 1993;329(8):542-4. [Medline].
7. Currie BJ. Clinical Toxicology: A Tropical Australian Perspective. Ther Drug Monitor. 2000;22(1):73-78. [Medline].
8. Yoshimoto CM, Yanagihara AA. Cnidarian (coelenterate) envenomations in Hawai'i improve following heat application. Trans R Soc Trop Med Hyg. May-Jun 2002;96(3):300-3. [Medline].
9. Loten C, Stokes B, Worsley D, et al. A randomised controlled trial of hot water (45 degrees C) immersion versus ice packs for pain relief in bluebottle stings. Med J Aust. Apr 3 2006;184(7):329-33. [Medline].
10. Little M, Mulcahy RF. A year's experience of Irukandji envenomation in far north Queensland. Med J Aust. Dec 7-21 1998;169(11-12):638-41. [Medline].
11. Anderluh G, Macek P, Lakey JH. Peeking into a secret world of pore-forming toxins: membrane binding processes studied by surface plasmon resonance. Toxicon. Sep 2003;42(3):225-8. [Medline].
12. Auerbach PS. Marine envenomations. N Engl J Med. Aug 15 1991;325(7):486-93. [Medline].
13. Bailey PM. Fatal envenomation by jellyfish causing Irukandji syndrome. Med J Aust. Feb 3 2003;178(3):139; author reply 139-40. [Medline].
14. Bailey PM, Little M, Jelinek GA, Wilce JA. Jellyfish envenoming syndromes: unknown toxic mechanisms and unproven therapies. Med J Aust. Jan 6 2003;178(1):34-7. [Medline].
15. Blumenthal KM, Seibert AL. Voltage-gated sodium channel toxins: poisons, probes, and future promise. Cell Biochem Biophys. 2003;38(2):215-38. [Medline].
16. Brown CK, Shepherd SM. Marine trauma, envenomations, and intoxications. Emerg Med Clin North Am. May 1992;10(2):385-408. [Medline].
17. Burnett JW, Calton GJ. Jellyfish envenomation syndromes updated. Ann Emerg Med. Sep 1987;DA - 19871001(9):1000-5. [Medline].
18. Burnett JW, Hepper KP, Aurelian L, Calton GJ, Gardepe SF. Recurrent eruptions following unusual solitary coelenterate envenomations. J Am Acad Dermatol. Jul 1987;17(1):86-92. [Medline].
19. Burnett JW, Purcell JE, Learn DB, Meyers T. A protocol to investigate the blockade of jellyfish nematocysts by topical agents. Contact Dermatitis. Jan 1999;40(1):55-6. [Medline].
20. Burnett JW, Weinrich D, Williamson JA, et al. Autonomic neurotoxicity of jellyfish and marine animal venoms. Clin Auton Res. Apr 1998;8(2):125-30. [Medline].
21. Dawson AH. Fatal envenomation by jellyfish causing Irukandji syndrome. Med J Aust. Feb 3 2003;178(3):139; author reply 139-40. [Medline].
22. Diochot S, Baron A, Rash LD, et al. A new sea anemone peptide, APETx2, inhibits ASIC3, a major acid-sensitive channel in sensory neurons. EMBO J. Apr 7 2004;23(7):1516-25. [Medline].
23. Diochot S, Loret E, Bruhn T, et al. APETx1, a new toxin from the sea anemone Anthopleura elegantissima, blocks voltage-gated human ether-a-go-go-related gene potassium channels. Mol Pharmacol. Jul 2003;64(1):59-69. [Medline].
24. Fenner PJ, Hadok JC. Fatal envenomation by jellyfish causing Irukandji syndrome. Med J Aust. Oct 7 2002;177(7):362-3. [Medline].
25. Ishikawa T, Vucenik I, Shamsuddin A, et al. Two new actions of sea nettle (Chrysaora quinquecirrha) nematocyst venom: studies on the mechanism of actions on complement activation and on the central nervous system. Toxicon. Dec 15 2004;44(8):895-9. [Medline].
26. Kizer KW. Marine envenomations. J Toxicol Clin Toxicol. 1983-1984;21(4-5):527-55. [Medline].
27. Lotan A, Fishman L, Loya Y, Zlotkin E. Delivery of a nematocyst toxin. Nature. Jun 8 1995;375(6531):456. [Medline].
28. Lotan A, Fishman L, Zlotkin E. Toxin compartmentation and delivery in the Cnidaria: the nematocyst's tubule as a multiheaded poisonous arrow. J Exp Zool. Aug 15 1996;275(6):444-51. [Medline].
29. Lumley J, Williamson JA, Fenner PJ, et al. Fatal envenomation by Chironex fleckeri, the north Australian box jellyfish: the continuing search for lethal mechanisms. Med J Aust. May 16 1988;148(10):527-34. [Medline].
30. MacSween RM, Williams HC. Seabather's eruption--a case of Caribbean itch. BMJ. Apr 13 1996;312(7036):957-8. [Medline].
31. McGoldrick J, Marx J. Marine evenomations Part 2: invertebrates. J Emerg Med. 1992;10:71-77. [Medline].
32. Oliveira JS, Redaelli E, Zaharenko AJ, et al. Binding specificity of sea anemone toxins to Nav 1.1-1.6 sodium channels: unexpected contributions from differences in the IV/S3-S4 outer loop. J Biol Chem. Aug 6 2004;279(32):33323-35. [Medline].
33. Palumbo A. Nitric oxide in marine invertebrates: a comparative perspective. Comp Biochem Physiol A Mol Integr Physiol. Oct 2005;142(2):241-8. [Medline].
34. Pearn J. The sea, stingers and surgeons: the surgeon's role in prevention, first aid and management of marine envenomations. J Pediatr Surg. 1995;30:105-110. [Medline].
35. Silfen R, Vilan A, Wohl I, Leviav A. Mediterranean jellyfish (Rhopilema nomadica) sting. Burns. Dec 2003;29(8):868-70. [Medline].
36. Thomas CS, Scott SA, Galanis DJ, Goto RS. Box jellyfish (Carybdea alata) in Waikiki. The analgesic effect of sting-aid, Adolph's meat tenderizer and fresh water on their stings: a double-blinded, randomized, placebo-controlled clinical trial. Hawaii Med J. Aug 2001;60(8):205-7, 210. [Medline].
37. Tibballs J. Australian venomous jellyfish, envenomation syndromes, toxins and therapy. Toxicon. Dec 1 2006;48(7):830-59. [Medline].
38. Villar RM, Gil-Longo J, Daranas AH, et al. Evaluation of the effects of several zoanthamine-type alkaloids on the aggregation of human platelets. Bioorg Med Chem. May 15 2003;11(10):2301-6. [Medline].
39. Watters MR, Stommel EW. Marine Neurotoxins: Envenomations and Contact Toxins. Curr Treat Options Neurol. Mar 2004;6(2):115-123. [Medline].
40. Yeung SY, Thompson D, Wang Z, et al. Modulation of Kv3 subfamily potassium currents by the sea anemone toxin BDS: significance for CNS and biophysical studies. J Neurosci. Sep 21 2005;25(38):8735-45. [Medline].

Article Last Updated: Feb 13, 2008