Irukandji syndrome

#KYJ - Irukandji Syndrome

They only live for about 6 months, they have 24 eyes, 4 stomachs, each with their own anus, and are no bigger than your thumb nail; but , they punch way above their weight by packing a sting that places them into the top 10 deadly venomous animals in the world.

Only a handful of deaths have been attributed to a collection of jellyfish stings known collectively as Irukandji, but the syndrome that their stings invoke always require hospital admission for analgesia, and cardiac monitoring. 

The most common offender Carukia barnesi, (identified in 1964 and named after its discoverer, Jack Barnes, is one of up to 16 species all thought to inflict the sting with venom causing what is now called Irukandji Syndrome.   There isn’t one “Irukandji jellyfish”, so with similar biology but different genetic features, it is tangible to see their venom effects can be difficult to pin down.

What is known is that these jellyfish uniquely have stinging cells (nematocysts) on not only their tentacles (of which there are four), but also in their Bell.  There is no safe place to handle them.

Their venom is thought to contain a nerve agent that acts to modulate sodium channels.  The effects cause rapid nerve firing .

Symptoms

5-30 minutes after a sting, the victim will experience severe generalised pain or cramps, 

GI symptoms of Diarrhoea, nausea and vomiting, 

Sympathetic symptoms localised or general sweating, restlessness, anxiety, headache,large muscle cramps and painful back spasms, and a classic sense of doom.

Pain from Irukandji can last weeks, and has been reported as the proverbial “10 out of 10”

Irukandji Syndrome can cause pulmonary oedema (likely cardiogenic) as acute hypertensive crisis is a frequent symptom, that has lead to stroke.

These stings hospitalise dozens of people world wide, and in Australia.  

The flourish in warm waters where hard coral is abundant (reefs). They are a family of jelly fish that actively hunt fish in the reef ecosystem, and are attracted to light.   What is sinister is that their annual blooms are being recorded as far south in the Australian east coast as Hervey Bay, and the southern migration each year correlated with warmer ocean currents.   The estimate from researcher is that their impact on the massive Gold and Sunshine Coast tourist industry will be inevitable as they march down our coast line.

Treatment.

Phase 1 - First aid

The first aid for suspected Irukandji stings is DRSABCD, and liberal dousing with vinegar.

While the vinegar does nothing for the pain or symptoms from stinging cells that have shot their load, the acid is thought to disable the unfired cells from further envenomation.

A few years ago Associate Professor Jamie Seymour from the Australian Institute of Tropical Health and Medicine (JCU in Cairns) reported that vinegar can actually cause discharge of stinging cells worsening the envenomation buy up to 50%, he stated "That's a big amount, and that's enough to make the difference, we think, between someone surviving and somebody dying."

That said, the Australian Resuscitation Council continues to recommend using vinegar.  So what to do?  More research is needed on the vinegar thing.

Phase 2- hospital management.

Pain and cardiovascular management is the priority.   Massive IV narcotic use and even sedation with ventilator support may be necessary.

There is no Antivenom or reversal agent.

Supportive use of Antihypertensives, and antihistamines are indicated.   Magnesium Sulphate is thought to be cardio protective and aids in the extreme haemorrhagic stroke risking hypertension.

These people go on to experience excruciating pain for days to weeks, so analgesia will be their friend.   Of the doom and dread and pain, one of my patients stated:

“For the first hour I was worried I would die, then for the next few hours, I was worried I wouldn’t!”

The jellies are coming more prevalent, and as more people are being stung in further southern parts of the coast, clinicians in places like south east Queensland will soon notch up their first Irukandji Syndrome patient in the annals of the reflective journals.

Written by Rob Timmings

@ECT4Health 

#Irukandji #ECT4Health