Symptom in search of a toxin: muscle spasms following bites by Old World tarantula spiders (Lamprope

[edesign]

"Symptom in search of a toxin: muscle spasms following bites by Old World tarantula spiders (Lampropelma nigerrimum, Pterinochilus murinus, Poecilotheria regalis) with review"

http://qjmed.oxfordjournals.org/content/102/12/851

I had posted this in the FB group but since that's mainly a photo-sharing group it received a whopping 3-4 likes and no real discussion. The case reports are well-written. @viper69, you might find them a bit more informational when they discuss blood tests due to your bg.

Just a short excerpt from Case 1, he had already been dealing with symptoms for the first two days, do read the article in its entirety though.

Forty-eight hours after the bite, he finally presented to hospital in desperation. Two faint puncture wounds 8 mm apart with surrounding erythema were visible on the radial aspect of the bitten finger which was swollen together with the whole of the left hand, restricting interphalangeal joint movements. The patient's skin was clammy to touch and he had a tachycardia of 125 beats per minute but a normal blood pressure. The muscle spasms were so severe that it proved impossible to give him an intramuscular injection of tetanus toxoid. He was admitted for observation, but trismus and generalized spasms continued to increase until ∼4 days after the bite, after which they declined and had disappeared completely 7 days after the bite. There was no fever, chest pain or respiratory symptoms. Routine blood tests, including differential white blood count, were within normal limits, but the serum creatine kinase was 1062 iu/l (normal <195 iu/l), later falling to normal by the time he was discharged. Plasma electrolyte concentrations, including Na+ and Ca2+ were normal. The total Ca2+ concentration corrected for serum albumin was initially 2.28 mmol/l (normal 2.25–2.6 mmol/l) and subsequently ranged from 2.39 to 2.44 over the next 3 days. The admission electrocardiogram (ECG) confirmed a sinus tachycardia with a ventricular rate of 114 beats per minute. Subsequent traces showed no atrial or ventricular tachyarrhythmias. Serial troponin-I cardiac enzyme levels were not elevated. Oral diazepam and six hourly intravenous calcium gluconate injections were given in an attempt to relieve the spasms but the patient was not convinced that these treatments helped at all.

"Conclusions: Bites by several genera of African, Asian and Australasian tarantulas can cause systemic neurotoxic envenoming. In the absence of available antivenom, severe persistent muscle spasms, reminiscent of latrodectism, pose a serious therapeutic challenge. Discovery of the toxin responsible would be of scientific and potential clinical benefit. Tarantula keepers should be warned of the danger of handling these animals incautiously."

 

[WeightedAbyss75]

I knew they were bad, but nit necessarily this bad. I guess it gives me more reason to be afraid of my OBT (not that I needed more proof )

 

[EulersK]

Very, very interesting read, thank you.

The aspects about muscle spasms are what intrigued me the most. Specifically:

Hanatoxin from the venom of the Chilean rose tarantula (Grammostola spatulata) and a growing number of related tarantula toxins inhibit activation of voltage-activated potassium (Kv) channels by interacting with their voltage-sensing domains. They might cause the disturbance of skeletal muscle excitability responsible for the tonic muscle spasms that have been described.

They are referencing a Grammostola in that quote, although similar muscle spasms were described in every single presented species. All of their subjects were bitten on their extremities, although in a couple cases a man was bitten in the hand and felt spasms in his leg. This shows that venom travels throughout the body, which should alarm many new hobbyists. A bite close to the chest could possibly result in heart arrhythmia, which is bad news for any animal. If anything, this article strengthens my belief that a wet bite on a small child or elderly person could very well result in death. This goes far beyond the simple pain receptors affected by a vanillotoxin - we're talking about a physical reaction of muscles.

 

[edesign]

WeightedAbyss75 (can I call you WA75 for brevity? lol), yeah, they definitely deserve respect. We can read reports all day but until it's actually experienced they're just words. I imagine it's a lot like mind-altering chemicals that the hippies made famous. Words can only describe so much of the actual experience. Don't get bit (like you need to be told haha)!

You're welcome. To add to that EulersK...

I had posted this in another thread just a few minutes ago too and it ties in here as well. It's a retyped copy of a field trip report to find S. calceatum and during the field trip a few people were bitten. The effects were included in the write-up. This includes one man who was bitten on his neck from one that flew/fell out of the tree that another guy had climbed to catch it and fell on the other man's face. Collateral damage

http://arachnoboards.com/threads/stromatopelma-bites.5832/

The first accident involved a freshly recruited (and paid) climber who worked his way up the tree - much to my horror - without belting himself like they would in Guinea or Guinea Bissau. The man was followed attentively by two colleagues who watched him reach the crown of the tree. the "hunter" exclaimed that he'd found the nest he was talking about, slipped his hand underneath the frond and was immediately bitten once in the palm of the hand. Since he hadn't belted himself and he was forty feet high, he couldn't let go of the palm frond and was bitten a second time in the hand.
The man immediately came down the tree, without the spider, and was tended at once with an Aspivenin extractor. Pain spread very quickly to his elbow, then to his shoulder and chest area. After 3 1/2 hours, , he had heart contractions that were extremely painful and lasted for a full half hour, a thoroughly nerve-racking experience since we were miles away from any civilisation. I visited the man the next day and the day after, and after the second day, his hand had swollen to twice its normal size: secondary infection. I treated it at once with a course of Bactrim.

...

I am sure that, without the immediate intervention of a primed and ready venom extraction kit, this young fellow might well have died. His throat was swollen and the pain radiated to his face, optical nerves, chest with heart contractions starting less than two hours after the bite, with the pain spreading downwards to his gonads..... a most horrible place to feel that kind of pain.
The heart contractions ceased after another hour and forty minutes. The aspivenin kit had been used within 40 seconds and was used for forty minutes, no doubt bruising the area around the bite. I tried to reassure the victim as best I could, and was relieved to hear him say that the pain was receding...six hours and a half after the bite had been inflicted.
In later days, the soldier was off-duty for a week, and when I left he still complained that his neck and throat area sometimes felt slightly painful.

Although I would consider death as almost impossible, bites in certain areas of the body (like the described neck-bite) or in persons with a faulty heart could be extremely dangerous. Stromatopelma is the link between the relatively harmless mass of Theraphosids, and the few species that can be life-threatening to man. It certainly isn't a species that is to be neglected in case of serious bites, and it has to be considered as venomous since it does cause systemic distress that follows a particular pattern and always involves problems with the heart. Stromatopelma should be reserved for the serious worker.

 

[EulersK]

Exactly, thank you for posting that. The only thing that I dislike about having an anecdote of an S. calceatum is that it may lure some hobbyists into a false sense of security. It may be reasoned away that this species has some of the most potent venom in the hobby, but that's not the point of the story. The moral is that a wet bite in critical locations of the body can result in terrible side effects. A wet S. calceatum bite to an adult man could be equivalent to a wet pokie bite to a teenager. The simple fact is that (as was brought up in the original posted article) not nearly enough research has been done on the venoms of these spiders.

It seems to me that the main concern here is venom that interferes with the potassium channels present in all nervous systems. For the record, we know that both arthropods and mammals have potassium gates, although logistically they often work in vastly different manners. Vanillotoxins are what get the animosity due to the incredible pain, but that's about where their danger ends (shock from the pain aside). To me, it's pretty clear what should be researched above all else. Which spiders have high concentrations of venom that will interfere with potassium channels?

Ready for some speculation?
Reading this article brought something to mind that someone may have an answer to. The venoms with high concentrations of vanillotoxins seem to have largely evolved in Asia and Africa, but are nearly absent in NW species. It should also be noted that OW species tend to be much smaller and delicate than their NW cousins. It stands to reason that these OW spiders developed incredibly painful bites to help compensate for their size and fragility. On top of that, their venom also needs to kill their prey as quickly as possible lest it escape, or worse, do harm back. More often than not, it is not the OW species that are eating small mammals, snakes, fish, and lizards - it is the large NW species, especially of South America. However, these NW species have size on their side. In the same way a giant python can overpower its prey, large spiders can simply wait for their prey to die from a combination of exhaustion, mechanical damage of fangs, and mild venom. Smaller OW species do not have this luxury in the same way that small, highly venomous snakes don't have that luxury.

 

[Abyss]

I have a HEALTHY respect for all my soecimems weather considered "hot" or not.
As a child i captured as many spiders as possible (when i say kid i mean as early as i can remember, my first memory as far back as i can remember is handling a jumping spider lol).
In doing this, i have been bitten more times then i can even begin to recall. Over the years i develiped a fairly severe alergic reaction. The latest bite from a Argiope (garden spider) when i was around 12-14 yrs old resulted in an emergency room visit, steriod injections, and draining the swelling around my eyes as they were afraid the pressure was going to literally pop my eyes from their sockets. Other instances from my youth involved my throat swelling shut, etc. none of which detered my love and interest in spiders.

My love for the hobby led me to tarantulas naturally (thankfully after i was better informed, older, and much more experienced) but i take extra care when rehousing, feeding, and doing maintenance as i keep mostly some of the more "hot" T's and have no doubt i wouod be in serious trouble fast if i were to be bitten. My wife is always aware when im "messing with my T's" and regularly checks on me to be safe. Im a HUGE fan of long tongs even for slings and no matter what im doing, i make sure to always be well aware of where the T is an what its posture is.

sry to hijack, just seemed like a good place/time to share a bit of my story haha

 

[WhitenerJ]

I have a question about venom potency between slings and adults. How much more potent is a mature adult Pokie vs a one inch sling? Is the potency the same and if so does the size of the fangs make a big difference on the effects of the venom.

 

[Venom1080]

great read, thanks.

 

[Venom1080]

I have a question about venom potency between slings and adults. How much more potent is a mature adult Pokie vs a one inch sling? Is the potency the same and if so does the size of the fangs make a big difference on the effects of the venom.

im pretty positive the venoms the same potency, but there is much less venom in a 1" spider compared to its adult counterpart. the big fangs just mean it can inject more venom. so not more potent but i imagine symptoms would be much worse just due to the amount of venom injected.

 

[viper69]

"Symptom"

Thanks, but I read this article when it came out in 2009

I knew they were bad, but nit necessarily this bad.

Well, you know, we just make this stuff up about how serious OW bites can be for people. It's how we get our kicks.

I have a question about venom potency between slings and adults. How much more potent is a mature adult Pokie vs a one inch sling? Is the potency the same and if so does the size of the fangs make a big difference on the effects of the venom.

The proteins made by a sling are the same as those by an adult. So their affinity for their targets is the same. Fang size has no bearing on the proteins in the venom. The fang is only part of the delivery system.

I think all too often people confuse/wonder/think that because the animal is smaller/younger than an adult that it's less dangerous.

The most venomous animal in the world fits on your thumbnail and kills you in a few minutes if I recall correctly.

 

[EulersK]

The most venomous animal in the world fits on your thumbnail and kills you in a few minutes if I recall correctly.

The box jellyfish, yes? Fascinating little creature. The poison dart frog is quite impressive as well, even moreso when you realize that they're not naturally poisonous at all.

 

[viper69]

The box jellyfish, yes? Fascinating little creature. The poison dart frog is quite impressive as well, even moreso when you realize that they're not naturally poisonous at all.

Yes and no. Specifically the box species Irukandji

Indeed they aren't at all. It's something in the food supply that is likely converted/modified into toxins. It may not exactly be the insects, nor the insects' food. Frog toxicity may involve the microbiome of their prey AND the frog's microbiome as well.

 

[edesign]

Thanks, but I read this article when it came out in 2009

Welcome. Next time I search I'll search using the address rather than the title. I see now that you had referenced it before. Definitely deserves its own post though.

...but that's not the point of the story. The moral is that a wet bite in critical locations of the body can result in terrible side effects. A wet S. calceatum bite to an adult man could be equivalent to a wet pokie bite to a teenager. The simple fact is that (as was brought up in the original posted article) not nearly enough research has been done on the venoms of these spiders.

Enjoyable post Eulers. I'm not too familiar with venom/toxin details. Pretty much all the bite reports on this forum (I don't read any others with regularity) are bites to the extremities. I haven't seen any from OW's that involved bites to the chest, neck, or head but I doubt I've read all of them. The reactions people report from extremity bites can be quite severe. Couple that with the S. calceatum article and the description of the effects on the man who got bit on the neck and it's easy to see why you don't want them near your face.

Ready for some speculation?
Reading this article brought something to mind that someone may have an answer to. The venoms with high concentrations of vanillotoxins seem to have largely evolved in Asia and Africa, but are nearly absent in NW species. It should also be noted that OW species tend to be much smaller and delicate than their NW cousins. It stands to reason that these OW spiders developed incredibly painful bites to help compensate for their size and fragility. On top of that, their venom also needs to kill their prey as quickly as possible lest it escape, or worse, do harm back. More often than not, it is not the OW species that are eating small mammals, snakes, fish, and lizards - it is the large NW species, especially of South America. However, these NW species have size on their side. In the same way a giant python can overpower its prey, large spiders can simply wait for their prey to die from a combination of exhaustion, mechanical damage of fangs, and mild venom. Smaller OW species do not have this luxury in the same way that small, highly venomous snakes don't have that luxury.

Sounds reasonable. I hadn't thought it out very far. In what way are OW's more delicate than NW's though? I thought there were plenty of large OW's out there, enough that I wouldn't necessarily say that OW's tend to be "much smaller". It would be interesting to see a spreadsheet with the various species' typical adult sizes. Not trying to nit-pick I don't think you're wrong about the reason for venom strength, I had always just chalked it up to an alternative to urticating hairs (more attitude, worse venom, no urticating hairs), I had just never thought of OW's in either of those ways.

 

[viper69]

Exactly, thank you for posting that. The only thing that I dislike about having an anecdote of an S. calceatum is that it may lure some hobbyists into a false sense of security. It may be reasoned away that this species has some of the most potent venom in the hobby, but that's not the point of the story. The moral is that a wet bite in critical locations of the body can result in terrible side effects. A wet S. calceatum bite to an adult man could be equivalent to a wet pokie bite to a teenager. The simple fact is that (as was brought up in the original posted article) not nearly enough research has been done on the venoms of these spiders.

It seems to me that the main concern here is venom that interferes with the potassium channels present in all nervous systems. For the record, we know that both arthropods and mammals have potassium gates, although logistically they often work in vastly different manners. Vanillotoxins are what get the animosity due to the incredible pain, but that's about where their danger ends (shock from the pain aside). To me, it's pretty clear what should be researched above all else. Which spiders have high concentrations of venom that will interfere with potassium channels?

Ready for some speculation?
Reading this article brought something to mind that someone may have an answer to. The venoms with high concentrations of vanillotoxins seem to have largely evolved in Asia and Africa, but are nearly absent in NW species. It should also be noted that OW species tend to be much smaller and delicate than their NW cousins. It stands to reason that these OW spiders developed incredibly painful bites to help compensate for their size and fragility. On top of that, their venom also needs to kill their prey as quickly as possible lest it escape, or worse, do harm back. More often than not, it is not the OW species that are eating small mammals, snakes, fish, and lizards - it is the large NW species, especially of South America. However, these NW species have size on their side. In the same way a giant python can overpower its prey, large spiders can simply wait for their prey to die from a combination of exhaustion, mechanical damage of fangs, and mild venom. Smaller OW species do not have this luxury in the same way that small, highly venomous snakes don't have that luxury.

I think size has very little to do with venom toxicity if anything at all, I think that's purely a human oriented mode of thinking, ie larger is stronger etc.

How are OWs more fragile than NW Ts?

 

[WeightedAbyss75]

I think size has very little to do with venom toxicity if anything at all, I think that's purely a human oriented mode of thinking, ie larger is stronger etc.

How are OWs more fragile than NW Ts?

Yes, i do understand. Its my fault for not reading the forums rule. A newbie here. Bo worries it will not happen again. Thanks for your time.

No problem. Also, with regards to size, if they have the same venom potency then couldn't a small juvie be more dangerous than an adult. I figure like rattlesnakes, young spiders couldn't control their venom output as well and would give more "wet" bites than an adult might.

 

[viper69]

No problem. Also, with regards to size, if they have the same venom potency then couldn't a small juvie be more dangerous than an adult. I figure like rattlesnakes, young spiders couldn't control their venom output as well and would give more "wet" bites than an adult might.

Your thoughts on young rattlesnakes' venom ejection are not true. They have every bit as much control as adults. I heard that myth myself and contacted a rattlesnake expert who has studied venom ejection, there is no truth to it. That myth is just that, a myth, just like using a tourniquet to ward off effects of a snake bite is beneficial, also not true. In fact doing so, makes it much worse.

Producing toxins is a very energy/resourcses intensive process, it's highly beneficial to an animal that it have control over venom ejection.

 

[EulersK]

Back on topic.

I think size has very little to do with venom toxicity if anything at all, I think that's purely a human oriented mode of thinking, ie larger is stronger etc.

How are OWs more fragile than NW Ts?

I'd like to modify my original statement, now that I think about it. I shouldn't have brought up OW vs NW - rather, I should have said arboreal vs terrestrial. For the outliers of my example, NW terrestrials and OW arboreals would be it.

I was basing it purely on the observation that in terms of the ratio between leg span and weight, arboreals are indeed lighter and thus have less muscle mass. As we know, the incredible strength that arthropods have is largely due to their exoskeleton - this allows them to pack more muscle into a smaller area (along with the muscles being directly attached to the exoskeleton, but that's a moot point). With less muscle mass comes less strength, directly relating to how long they could hold on to prey. In terms of fragility, we'll once again look at the ratio of leg span to weight. They are simply smaller, meaning a smaller animal could hurt them much easier. Granted, an OW arboreal has a heck of a defense in their venom, but they can't rely on the defense of their size. Think about a predator: what would look like an easier meal, a thick, stocky 5" A. chalcodes or a lanky 5" P. ornata?

 

[magicmed]

No problem. Also, with regards to size, if they have the same venom potency then couldn't a small juvie be more dangerous than an adult. I figure like rattlesnakes, young spiders couldn't control their venom output as well and would give more "wet" bites than an adult might.

I think it's not really a question of potency, rather ease of injection. Say a sling with very potent venom bit a man's finger, if the finger is rough the small fang may not be able to break skin/penetrate all layers to get venom into the blood stream. Then you have to consider slings molt more frequently so their fangs may be soft and break off without injection. An adults larger fangs have no problem penetrating through skin, vascular tissue, muscle, anything on us but bone, really. So an injection if meant would be much easier for an adilt.

 

[WeightedAbyss75]

Back on topic.



I'd like to modify my original statement, now that I think about it. I shouldn't have brought up OW vs NW - rather, I should have said arboreal vs terrestrial. For the outliers of my example, NW terrestrials and OW arboreals would be it.

I was basing it purely on the observation that in terms of the ratio between leg span and weight, arboreals are indeed lighter and thus have less muscle mass. As we know, the incredible strength that arthropods have is largely due to their exoskeleton - this allows them to pack more muscle into a smaller area (along with the muscles being directly attached to the exoskeleton, but that's a moot point). With less muscle mass comes less strength, directly relating to how long they could hold on to prey. In terms of fragility, we'll once again look at the ratio of leg span to weight. They are simply smaller, meaning a smaller animal could hurt them much easier. Granted, an OW arboreal has a heck of a defense in their venom, but they can't rely on the defense of their size. Think about a predator: what would look like an easier meal, a thick, stocky 5" A. chalcodes or a lanky 5" P. ornata?

Just to play Devil's advocate, what predator would we be talking about? If I was a bird, I would definitly go for the big, slow, and less venomous spider there. Especially with A. chalcodes colors, a predator might not even see the pokie. I think it all depends on the predator. And also, most T's are super fragile anyway. I would think that any animal able to hurt and kill a pokie would also be able to easily kill an A. chal, with it's lack of speed and camoflage. Also, now I know that size is not = to venom control. The more you know Also, I do think ease of injection plays a part to. More mechanical damage + deeper venom input is good overall.

 

[viper69]

Back on topic.



I'd like to modify my original statement, now that I think about it. I shouldn't have brought up OW vs NW - rather, I should have said arboreal vs terrestrial. For the outliers of my example, NW terrestrials and OW arboreals would be it.

I was basing it purely on the observation that in terms of the ratio between leg span and weight, arboreals are indeed lighter and thus have less muscle mass. As we know, the incredible strength that arthropods have is largely due to their exoskeleton - this allows them to pack more muscle into a smaller area (along with the muscles being directly attached to the exoskeleton, but that's a moot point). With less muscle mass comes less strength, directly relating to how long they could hold on to prey. In terms of fragility, we'll once again look at the ratio of leg span to weight. They are simply smaller, meaning a smaller animal could hurt them much easier. Granted, an OW arboreal has a heck of a defense in their venom, but they can't rely on the defense of their size. Think about a predator: what would look like an easier meal, a thick, stocky 5" A. chalcodes or a lanky 5" P. ornata?

I see what you are saying, but I don't think size is related to potency.

Also, your idea on arthropod strength is completely wrong as I understand it. Don't get me wrong their exoskeleton plays a role from a material science perspective, but it's not the primary reason.

Google up "why are ants so strong", and you'll see the reason why insects are so strong is more about physics and their small size, and surface to volume ratio. Being a math major, you'll understand it quite easily.