Playing in or drinking stagnant water may expose dogs to micrycystin. Photo Credit: Ronald Laubenstein, USFWS
A paper on sea otters dying from exposure to cyanobacteria along the coast of California may have saved the life of a dog in Montana.
Dr. Melissa Miller and her team from the Marine Wildlife Veterinary Care and Research Center of the California Department of Fish and Game had looked into potential treatments for microcystin poisoning after a number of sea otters died from exposure. An experimental treatment she found led to the cure of the Montana dog.
Decoded Science, in an interview with Dr. Kelly Rankin, the Montana dog’s veterinarian, learned more about the use of Cholestyramine and other supportive care to treat microcystin, exposure.
Blue-green Algae Toxins Affect Many Species
This problem is not new. Cyanobacteria, blue-green algae, are just one of the many toxic forms of harmful algal blooms (HABs).
Red tide, for example, is caused by a completely different algae, and even within the cyanobacteria family, microcystin is only one variety. Different HABs act in different ways; some affect the nervous system, some the gastrointestinal systems and some, like microcystin are hepatotoxic, affecting the liver.
Outside the US there is a report of three dogs in the Netherlands dying from microcystin poisoning, the first confirmed cases in that country. Humans, birds, fish, and even marine mammals have died from exposure to microcystins.
In the California case, 21 sea otters deaths were linked to microcystin exposure. Postmortem testing confirmed the cause of death but until then no one knew what was affecting them. In fact, prior to that incident, it was thought that microcystins would not survive in the marine environment.
What Dog Owners Should Know About Exposure to Cyanobacteria
Dr. Rankin suggests that dog owners not allow their pets to play in or drink water that looks slimy, particularly if the slime has an iridescent blue-green color. Given that microcystins are found in the marine environment, as in the case of the sea otters in California, and in deserts, as described by a letter to the Veterinary Record, any healthy dog that exhibits sudden symptoms with no other obvious exposure risks, should be considered as a potential microcystin case.
In a report to the Veterinary Record, the alga was identified in the dried crusts on the desert surface. It is presumed that the dogs ingested some of the cyanobacteria while drinking rainwater from puddles. Two of the four dogs in this report died, the other two recovered.
What are the Symptoms of Microsystin Toxicity
So what should owners be aware of after a trip to the lake, or after their dog has been drinking from stagnant puddles? Lethargy, anorexia and vomiting were the initial symptoms.
Blood tests showed elevated liver enzymes. Five days after exposure to the algal bloom other evidence of liver failure, including dark urine, tarry stools, and blood coagulation problems were noted. In other cases, dogs have also developed severe diarrhea.
First Reported Successful Cholestyramine Treatment in a Micrycystin Exposed Dog
When Dr. Rankin first admitted the dog, she began supportive care, which included IV fluids, antibiotics and a nutritional supplement, Denmarin. Dr. Rankin told Decoded Science that she has used Denmarin, which combines milk thistle and S-Adenosyl Methionine (S-AME) for other dogs with liver problems as it supports liver function. While this may have helped, Dr. Rankin told Decoded Science that the product is only available as a large pill, thus not an option for dogs that are vomiting or nauseous.
As her patient’s symptoms worsened, Dr. Rankin began searching for more information on what could be causing the problem and what else she could do. She was eventually put in touch with Dr. Miller who told her about a product that had only been tested in the laboratory on rodents. Dr. Rankin elected to try the experimental drug, Cholestyramine, one of the early human medications for the control of high cholesterol, hence the name.
Over the next two days the dog improved dramatically and was soon able to go home. A recheck 17 days later showed that her liver enzyme levels had returned to normal.
Results for One Dog Are Not A Guarantee for Success in Every Case
Because this report documents a single case, not a controlled study, the results must be interpreted with caution. Cholestyramine binds strongly to bile salts which attach to microcystins and to the microcystins themselves so it is likely to be helpful in other microcystin poisoning cases.
On the other hand, Cholestyramine would not necessarily help a dog who is experiencing neurological or other organ symptoms as it is unknown whether it binds to other types of toxic algae.
It is also important to remember that not every animal will react in the same way to a medication. The dog in the study did not experience any serious side effects but other dogs may be more sensitive.
Nonetheless, treatment with Cholestyramine is worth discussing with your veterinarian should your dog, who might have been exposed to water sources that may contain cyanobacteria, suddenly become seriously ill with severely elevated liver enzymes.
According to Dr. Rankin, the treatment turned her patient around quickly, and at a point where her condition was worsening despite intense supportive care. And Cholestyramine is inexpensive and readily available at any pharmacy.
© Copyright 2014 Dawn M. Smith, All rights Reserved. Written For: Decoded Science
Dawn M. Smith says
Kim-I am so sorry for your loss and for the difficult situation you were in.
In addition to her incredible efforts to save her patient, Dr. Rankin was very helpful to me when I was writing the article. She was pleased to be sharing the information with a wider audience but also wanted to be sure Dr. Miller was given due credit for tracking down the experimental drug and sharing her insights. So not just one, but two vets should be acknowledged for their dedication.
Thank you for helping spread the word.
Dawn, I completely agree. I didn’t realize that I left that part out of my comment, but I certainly meant to give Dr. Miller credit as well so thank you for bringing that to my attention. Her work is amazing and her incredible research is what enabled Dr. Rankin to make that decision when caring for the dog. Without Dr. Miller, the outcome may have been very different. I am extremely fortunate in that my other dog, who jumped in the same small body of water that day, came out completely unharmed and never showed any signs of toxicity. He is a healthy 5 year old lab that is still with me today.
With your permission I would love to put a link to this article on my company website. Please feel free to email me and let me know if this is something that you would allow.
Thank you,
Kim
Dawn,
I can’t thank you enough for writing this article. I have been trying to learn as much as possible about blue-green algae toxicity in dogs over the past few months and I strongly feel that this article could be of great benefit to the veterinary community. I stumbled upon this article a while back and I have returned to it many times since then. This topic is something that weighs heavy on my heart since my own dog, a seven year old healthy and happy lab, passed away this past September from blue-green algae poisoning which was misdiagnosed as heat stroke from the beginning. Many veterinarians continued to tell me it was heat stroke despite the fact that everything I had told them in no way indicated that he could have overheated. The majority of them did not know what blue-green algae was and neither did I. I did tell them about the water that he had briefly jumped into shortly before he collapsed though and they agreed that he got into some very green water because he had been vomiting green foam while he was under their care. He did have a fever, but the highest his temperature got to was 103 and it was brought down to normal rather quickly. After searching for answers on my iPhone while I waited I stumbled upon an article that talked about blue-green algae poisoning and I brought it to their attention. The vets said they didn’t know much about it and dismissed my research and told me that it was heat stroke. I do not know Dr. Rankin, but I strongly feel that the world needs more great vets like her. I know that had my dog received the same treatment she administered to the dog in the article that he most likely would not have made it and the outcome would have probably been the same in the end given that he passed away so quickly. At the same time, Dr. Rankin did what I would hope every vet would do. When she did not have an answer, she researched everything possible and really gave her all to try and save this dog. My dog was not as fortunate to have that kind of care. While I was by his side the vets were making small talk with each other and coming over periodically to monitor his vitals. It was the middle of the night and I could not transfer him since there were no other options open at that time.
I hate to bring up a sad story, but I want people to know about the dangers and how horrible blue-green algae is. My dog was transferred to another emergency vet that morning and they felt it was indeed blue-green algae poisoning but by that time he was too far gone and he passed away shortly after. In close to 24 hours he was gone. I strongly feel that this article is about much more than educating people on the dangers of blue-green algae and bringing awareness to a potential treatment. Whether you realize it or not, this article also encompasses absolutely everything that defines a great veterinarian. It is about thinking outside of the box and putting a dogs life before anything else and doing what you can to get that dog better, even if it means having to make a guess that could potentially not work or make things worse. It is about trying to find an answer when you don’t have one. This vet did not just sit there and let time take it’s course on the dog. She stepped up to the plate and did everything she could and even if the dog were to have died in the end she would have known that she tried the best she could. The dog’s owners would have also been at peace knowing that the vet tried everything. I hope more people read this article since blue-green algae is not going away anytime soon. I am from Oregon and I am amazed at how many pet owners and animal health experts here do not know what blue-green algae is. I used to be one of those people. In the end I wish more could have been done for my dog and I wish I knew then what I know now. I can’t blame the vets that treated my dog for doing what they were taught and trying to follow a textbook scenario even if some of the signs were indicating something else could’ve been wrong. At the same time, I wish my dog could have had a vet like Dr. Rankin that tried her hardest and thought outside of her own knowledge when she didn’t have answers. In my opinion, that is the definition of a true veterinarian. Thank you again for writing such a great article with a great impact.