Studies

Chironex fleckeri
Australia

O'Reilly et al. 2001: Prospective study of patients (n=40) presenting with jellyfish stings at a teching hospital in tropical Australia between August 1999 and July 2000. Identification (C. fleckeri): sticky tape sampling and microscopic identification of nematocysts (n=39). Presentations consistent with C. fleckeri  in 28 cases. Sticky tape sampling positive for C. fleckeri nematocysts in 23 cases. Nematocysts not detected in 10 cases. All microscopically confirmed C. fleckeri stings had typical clinical presentations.

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Case reports

Chironex fleckeri
Australia
Beadnell et al. 1992: 1 sting. Identification: C. fleckeri; criteria: typical tentacle "prints" ("frosted ladder" pattern) on the skin.
Boyd 1984: 1 sting. Identification: C. fleckeri; criteria: typical tentacle "prints" ("frosted ladder" pattern) on the skin.
Fenner et al. 1989a: 2 stings. Identification: C. fleckeri; criteria: typical tentacle "prints" ("frosted ladder" pattern) on the skin 2/2, tentacle adhering to the skin 1/2.
Flecker 1952a: 1 sting. Identification: C. fleckeri (see also Williamson et al. 1980).
Horne 1988: 1 sting. Identification: C. fleckeri; criteria: typical tentacle "prints" ("frosted ladder" pattern) on the skin; Chironex nematocysts.
Kingston and Southcott 1960: 2 stings. Identification: C. fleckeri or Chiropsalmus quadrigatus; criteria: nematocysts.
Lumley et al. 1988: 1 sting. Identification: C. fleckeri; criteria: typical tentacle "prints" ("frosted ladder" pattern) on the skin; Chironex nematocysts on the skin and in histological preparations.
Maguire 1968: 1 sting. Identification: C. fleckeri; criteria: typical tentacle "prints" ("frosted ladder" pattern) on the skin.
Sutherland 1979: 1 sting. Identification: C. fleckeri; criteria: typical tentacle "prints" ("frosted ladder" pattern) on the skin.
Williamson et al. 1980: 1 sting. Identification: C. fleckeri; criteria: typical tentacle "prints" ("frosted ladder" pattern) on the skin; tentacles adhering to the skin.
Williamson et al. 1984a: 2 stings. Identification: C. fleckeri; criteria: typical tentacle "prints" ("frosted ladder" pattern) on the skin.

Malaysia
Chand and Selliah 1984: 1 sting. Identification: attributed to C. fleckeri; criteria: description of the jellyfish by the patient.

Oman
Cooper 1991: 1 sting. Identification: attributed to C. fleckeri; criteria: clinical picture.

Thailand
Laing and Harrison 1991: 1 sting. Identification: C. fleckeri; criteria: typical tentacle "prints" ("frosted ladder" pattern) on the skin.

Chiropsalmus quadrumanus
USA (Texas, Gulf of Mexico)
Bengston et al. 1991: 1 sting. Identification: nematocysts.

Signs & symptoms

Autopharmacological effects

Anaphylactic reactions, in particular anaphylactic shock, may be difficult to distinguish in differential diagnostic terms from systemic toxic effects.

Local effects

Whiplash-like skin lesions with a typical "frosted ladder" pattern (corresponding to the transverse bands on the tentacles), red, purple or brown (Fig. 4.11). The skin lesions pass through a blister stage then develop into necroses that affect the entire thickness of the skin. They result in scars, possibly also keloid scars. Debilitating pain (Barnes 1960, Bengston et al. 1991, Hartwig et al. 1980, O'Reilly et al 2001, Strutton and Lumley 1988).

Paralysis of the ulnar nerve after tentacle contact in the region of the superficial course of the nerve on the elbow (Laing and Harrison 1991).

Neurological effects

Discussion regarding the significance of neurological compared to cardiac effects of the venom in cases of severe, life-threatening envenoming is still unresolved (Williamson et al. 1984b). Experimentally, respiratory arrest associated with a central nervous mechanism was found to be the terminal event (Freeman and Turner 1969). It was suggested that low doses of venom have a respiratory effect that influences the course of envenoming (Lumley et al. 1988). The mechanism of action of the venom components that cause neurological effects is unclear. The postulated central neurological effect of the venom has not been proven in humans (Lumley et al. 1988).

Signs of respiratory insufficiency/respiratory failure, respiratory arrest within minutes after the sting (Lumley et al. 1988). Severely bloated abdomen, urinary retention, erectile dysfunction, unchanged R-R interval on ECG during inspiration and expiration as well as carotid sinus massage. All these signs and symptoms were reversible (were interpreted as parasympathetic effects) (Chand and Selliah 1984).

Cardiac effects

Discussion regarding the significance of cardiac compared to neurological effects of the venom in cases of severe, life-threatening envenoming is still unresolved (Williamson et al. 1984b). It was suggested that high doses of venom have a cardiac effect that influences the course of envenoming (Lumley et al. 1988). Experimentally, the cardiotoxic effect is dominant (Endean and Sizemore 1988). This is supported by several clinical observations (Beadnell et al. 1992, Lumley et al. 1988). The mechanism of action of the venom components that cause cardiac effects is unclear. Impairment of calcium transport has been mentioned as a possibility. Cardiac dysrhythmias, cardiac insufficiency, cardiac failure and irreversible coma occur within minutes of the sting (Bengston et al. 1991, Lumley et al. 1988).

Other signs & symptoms

Nausea, vomiting.

Morbidity

1. Delayed hypersensitivity reactions: Itchy red maculopapular rash dotted along the intitial tentacle contact points consistent with urticaria occuring 7-14 days after the sting (11/19 followed up after stings positive for C. fleckeri nematocyts). Resolved spontaneously (7/11) and after treatment with oral antihistamines and topical steroids (4/11) (O'Reilly et al 2001).

2. Scarring and keloid formation after healing of the skin lesions.

Case fatality rate

Since 1884 at least 55 confirmed fatalities in the Indo-Pacific region, 40 of which occurred in northern Australia (Williamson et al. 1980).

Chironex fleckeri
1/1 (Flecker 1952),
1/1 (Lumley et al. 1988),
2/2 (Kingston and Southcott 1960)

0/28 patients with presentations consistent with C. fleckeri  of which 23 were confirmed by microscopy (O'Reilly et al 2001). 

Chiropsalmus quadrumanus
1/1 (Bengston et al. 1991).

Laboratory and physical investigations

1. ECG
Tachycardia and ventricular extrasystole (Beadnell et al. 1992).

2. ELISA

Within a few days after the sting, specific IgG antibodies are formed that persist for many months. The species of jellyfish that caused the sting can be identified retrospectively using antibody detection with an ELISA test. However, there are problems with specificity (Burnett et al. 1988a).

First aid

(Resuscitation Council website - http://www.resus.org.au/: Guideline 9.4.5 Envenomation - Jellyfish Stings; Fenner et al. 1989; Lumley et al. 1988)

1. Take the patient to land (risk of drowning!).
2. Inactivate the nematocysts remaining on the skin: a generous amount (>2 litres) of household vinegar 4–6(–10)% is poured over the affected areas of skin for at least half a minute. Subsequently the tentacles can be safely removed. Do not use any other liquids, as these may cause discharge of the nematocysts, e.g. alcohol (Hartwig et al. 1980).
3. "Major sting" (decreased consciousness and/or >50% of an extremity stung).
   
   • Respiratory or cardiovascular failure immediately after the sting: resuscitation (if possible).
   • Be prepared for the need to attempt resuscitation, and call for a doctor/ambulance or take the patient to a doctor/hospital.
4. "Minor sting":
   
   • Take the patient to a doctor/hospital, especially if it is a child, older person or a patient with pre-existing conditions (in particular cardiovascular disease).
5. Immobilise the patient, no physical effort during transport. Do not use pressure immobilisation bandages (Little 2002, Pereira et al 2000, Seymour et al 2002,  Australian Resuscitation Council website: Guideline 9.4.8 Envenomation - Pressure Immobilisation Technique)

Treatment (symptomatic)

1. Pain

Pethidine 1–2 mg/kg BW, repeat as needed (Fenner et al. 1989). In order to be effective, narcotic analgesics must be administered at a dose that is only possible if the conditions for treatment of respiratory depression are met (Beadnell et al. 1992) (see also below, Specific Treatment).

2. Cardiac dysfunction (cardiac dysrhythmias, hypotonia, cardiac failure)

• Toxic venom components from box jellyfish appear to be systemically active for only 15–20 min, as they are thermolabile. Cardiopulmonary resuscitation measures may thus be successful if they are maintained for a sufficient period of time (Williamson et al. 1984b).

Verapamil: The calcium channel antagonist and smooth muscle vasodilator verapamil was advocated in addition to antivenom administration on theoretical grounds and on the basis of animal experiments  (Beadnell et al. 1992, Bloom et al 1999, Burnett 1990, Burnett and Calton 1983, Burnett et al. 1990, Fenner et al. 1989, Lumley et al. 1988). Two animal studies came to the opposite conclusion demonstrating that verapamil worsens the outcome (Tibballs et al 1998, Ramasamy et al 2004). The controversy mounted in two Letters to the Editor of Toxicon, one making a case for (Burnett and Calton 2004) and one against the use of verapamil (Isbister et al 2004). Currently, the use of verapamil is not recommended, because it may worsen arterial hypotension and induce dysrhythmias (Bailey et al 2003).

3. Respiratory insufficiency, respiratory failure

Endotracheal intubation and artificial respiration (Lumley et al. 1988).

Toxic venom components from box jellyfish appear to be systemically active for only 15–20 min, as they are thermolabile. Cardiopulmonary resuscitation measures may thus be successful if they are maintained for a sufficient period of time (Williamson et al. 1984b).

4. Contraindicated medications
Calcium, positive inotropic agents (Lumley et al. 1988).

Treatment (specific)

Antivenom
Box jellyfish antivenom (CSL, Parkville, Australia). see MAVIN-Antivenom index

Indications

1. "Major sting (decreased consciousness and/or >50% of an extremity stung).
2. Clinical signs of respiratory insufficiency.
3. Clinical signs of cardiac dysfunction (in this case in combination with verapamil, see above).
4. Pain that cannot be controlled by other means (see above).
5. If scarring is expected, especially on skin areas where it would be cosmetically undesirable.

Dose

Initial dose, minimum 1 vial i.v.; up to 3 vials if there has been extensive tentacle contact. Repeat doses if the treatment is not successful. Children receive the same dose as adults (Fenner et al. 1989, Lumley et al. 1988).

Efficacy

Experience from treatment of individual cases:

1. Pain: antivenom is the most effective and fast-acting means of dealing with pain. The mechanism of action is not known (Boyd 1984, Horne 1988, Lumley et al. 1988, Sutherland 1979, Williamson et al. 1984a).
2. Skin lesions, scarring: antivenom reduces skin symptoms and thus scarring. However, if used for this purpose, antivenom should not be administered later than 4–6 h after the sting. The mechanism of action is unclear (Beadnell et al. 1992, Horne 1988, Lumley et al. 1988, Williamson et al. 1984a, b).
3. Neutralisation of lethal venom components: doubt regarding the extent to which the currently available box jellyfish antivenom (CSL, Parkville, Australia) inactivates the lethal components of the venom concerns the cardiotoxins in particular. Efficacy of the antivenom once cardiovascular failure has already commenced is completely unproven and very unlikely (Endean and Sizemore 1988).

Antivenom administration by trained ambulance personnel

The fact that the antivenom most probably only neutralises the lethal components of the venom if given immediately after the sting led to considerations regarding how to administer antivenom as quickly as possible on the beach. Thus ambulance personnel were trained to administer antivenom and have already used this knowledge a number of times with success (Beadnell et al. 1992, Fenner et al. 1989).