Canine Health Issues « AgilePooch Diaries

Rimadyl Toxicity – I wish I weren’t an expert…

October 19, 2011

… but I am.

Billy’s first exposure to Rimadyl was just over a year ago and was my fault – I left a bottle with about 10 of Jasmine’s chewable tablets on the counter after feeding time. Billy exploited the opportunity and as a result, he spent 3 days in the hospital for preventative diuresis. We were lucky and he walked away unscathed. After that, we made significant changes to the way we store the Rimadyl to avoid another accidental exposure.

We starting storing the dog food and medications on top of the fridge, with confidence that they were out of Billy’s reach. The meds we keep up there are in stainless steel water bottles with heavy screw tops. We thought that was safe – who wouldn’t? That strategy has worked fine for over a year, but it turns out that Billy’s determination far exceeds anything we could have imagined.

Day Zero: The Disaster Unfolds (Mon, 10/10/11)

At 6:00am on Monday morning, I flew to Salt Lake City for a 5-day conference, leaving Rich at home with the dogs. Sometime around noon, Billy managed to get access to the top of the fridge (there’s no counter or stool nearby, he must have just scaled the front somehow) and knocked nearly everything off onto the floor. He then took the stainless steel container of Rimadyl outside, unscrewed the top, and ate them all. I had recently refilled Jasmine’s prescription so there were around 150 tablets, an unimaginable overdose by any standards.

I chose to avoid the actual calculations until I was sure he was going to survive, but I have now determined that his exposure was ~425mg/kg. Therapeutic dosage is 4.4mg/kg, and the literature talks about renal concerns beginning at 40mg/kg. In other words, his overdose was massive – 100x therapeutic and 10x toxic.

Rich discovered the disaster around 1:30pm and had Billy at PetCare by 2pm. They began aggressive treatment immediately, which involves vomiting, activated charcoal, IV fluids for the kidneys, and meds to protect the liver and the GI tract. He somehow managed to survive the night and I flew home from Utah first thing Tuesday morning.

Days 1 to 5: To Hell and Back (Tues 10/11/11 – Sat, 10/15/11)

The vomiting subsided within a couple of days but he remained nauseous and had very little appetite. His kidneys had paid a price but appeared to have to have stabilized. Because of the massive amount he got, they opted to keep him on the fluids for an extra couple of days as a precaution. Our new concern at this point was the liver, which started to go south on Wednesday. His ALT (liver enzyme) rose dramatically from 62 on Tuesday (which is WNL) to 126 on Wed (way above NL), then 400 on Thurs. If the ALT had continued to rise at that rate into the 1000 range, we would expect acute (and potentially irreversible) liver failure to not be far behind. But it seemed to stabilize in the 400-450 range. His bilirubin (which causes jaundice) remained elevated, but was also unchanged between Wed and Thurs, which suggested it may have plateaued as well. He was definitely yellow, but his eyes seemed a little better on Thursday – I thought it might be my imagination, but the nurse said the same thing.

His clinical presentation has also improved. He began eating Thursday morning, and shows more and more real interest in food (rather than just humoring me by taking something out of my hand). By Friday morning he was seeking out the morsels that I tossed on the floor, that night he was catching them in mid-air, and on Saturday morning he actually offered simple behaviors, like sit and close. He will engage with a toy when I toss it and find the squeaker, but only once or twice. We go on short walks in the parking lot and he trots with his tail wagging, at least for a few steps at a time – he obviously fatigues very quickly and we’re keeping our visits short so he can rest.

Our schedule this week has been simple: visit at noon because that’s when they run the blood tests, stress all afternoon and evening, visit before bedtime, then try to sleep at night. The 24-hour wait between blood draws is excruciating, but we’re encouraged by the small clinical improvements we’re starting to see each time we visit. In fact, today for the first time, he tried to follow us out of the visiting room rather than going back to his cage with the nurse.

Day 7: More Signs of Hope (Mon, 10/17/11)

Saturday night’s visit was quite uplifting. His attitude had improved even from the morning and we got a glimpse of the Border Collie we know and love – catching his toy in mid-air, snatching it off the ground and shaking it, even a little light tugging, and bringing it back for more. His appetite is obviously improving, as is his willingness to “work” for food. On Sunday, the nurse was pleased to report that he was eating rice and chicken out of a bowl (“like a dog”) instead of only out of her hand. And the fact that he was interested in that sort of bland-ish food was also an improvement because we had previously only been able to entice him with “junk food” (the Dr’s term) like hot dogs, string cheese, and green tripe treats.

This afternoon, we got good news from his first urinalysis – no urinary casts. These casts, if present, are positive indicators of kidney tubular damage. Absence doesn’t necessarily mean no damage, but it’s still very encouraging. He’s also not spilling protein into his urine. Plus his bilirubin level has dropped significantly and he’s noticeably less jaundiced today. Liver and kidney blood values still not what we’d like them to be, but he continues to eat and play and his stamina is improving. And my friend Sarah is quick to remind me (after her first-hand experience with Rav’s acute failure of both liver and kidneys as a puppy), “look at the dog, not the numbers”.

Following the good results from the urinalysis, they started tapering his fluids in anticipation of sending him home soon.

Day 8: Homecoming! (Tues, 10/18/11)

I’m beyond thrilled to report that 8 days after admission, Billy is home from the hospital! I picked him up on my way home from work and here we are.

Clinically, he’s getting better every day. Today when I visited him at lunchtime, he ran full-speed across the parking lot to chase a squirrel on top of the fence. He obviously has some reconditioning to do after 8 days of lying around in a cage (and more recently a 5′x5′ “room”), but I’m sure that will come back quickly once he’s released to run freely on the back hill. I’m keeping him confined for a day or two while we re-introduce him and Zack, and also I’m going to be a lot more compulsive about daily mushroom checks. It’s that time of year, and even a small insult that wouldn’t normally be a problem could be real trouble now.

Long-Term Prognosis

Chemically and medically, we definitely have some fallout. His liver numbers are far from perfect, but the Dr. is optimistic that those will recover over time – the liver is very resilient and can regenerate. However, his kidneys have almost certainly sustained some level of permanent damage and we’ll probably have to manage chronic kidney disease throughout his lifetime. Based on his current chemistry, he’s labeled as Stage 2 (out of 4).

Next steps include nutritional research and consultation, guidance from an internist (preferably one who understands what it is that we do), and careful monitoring of blood work and hydration.

How do we protect him in the future?

We may not be able to. Dietary indiscretion is no joke, and neither is his drive to exploit vulnerabilities. We can’t put him in a bubble, so all we can do is continue to make adjustments and hope for the best.

We started by buying a new storage cabinet, which now houses all of the food, medications, and garbage containers. It includes a shelf at about the right height that now serves as our food and medication prep center (instead of the kitchen counter). The cabinet doors have hasp loops that will always be secured with a carabiner, and we have fabricated a nylon crossbar that inserts into the door handles for further security when we’re not here. And finally, the cabinet will be secured to the wall so he can’t pull it over.

I am sticking with the metal stainless steel water bottles, but I have purchased smaller 12-oz ones and will only store a limited number of meds (i.e. less toxic overdose potential) in the cabinet. The remainder will be stored safely somewhere else.

The other significant change is that Jasmine no longer gets tasty chewable Rimadyl tablets. I replenished her prescription with boring caplets. She won’t mind because she still likes Pill Pockets, which I buy by the case anyway, and which are also now secured in the new cabinet.

Soap Box: Don’t buy chewable Rimadyl

On the day Billy went to the hospital, there were three other dogs admitted for Rimadyl toxicity. One of them got it from its owner’s purse after having just been prescribed it therapeutically that day. Four dogs in one day in one hospital? Something is definitely wrong with this picture, and what’s wrong is packaging a toxic medication as a tasty treat.

Finally, I can breathe again

Last Monday night when I was alone in my hotel in Utah, I was certain I was going to lose my boy and I grieved. And my mood on Thursday night, after his liver went south, was equally dark or maybe even worse because I had let my guard down. But now he’s home, he’s hungry, he’s back to his happy playful joyful self, and he has no activity restrictions. I fully expect him to return to his agility training soon and hopefully he’ll lead a relatively normal life.

Life is good!

9 Comments | Rimadyl | Permalink
Posted by agilepooch

Splenic Tumors in Dogs – a Lay Person’s View

February 24, 2011

Bad things happen in the spleens of dogs. I don’t know why, I just know they do.

Medically speaking, canine splenic masses typically start as unremarkable “nodules”. From there, they often transform into one of two types of masses: hemangioma (a benign tumor) and hemangiosarcoma (a malignant cancer). Other types of masses also occur but these two are the most common. Unfortunately, because the spleen is a vascular organ, even the benign ones often have tragic results.

In my experience (and that of many dear friends), splenic masses result in one of the following three outcomes, often without diagnosis or warning:

They rupture and the dogs bleed to death
They metastasize and the dogs die of cancer in other organs (lungs, brain)
They get discovered by pure dumb luck and are dealt with surgically before #1 or #2 can occur

Scenarios #1 and #2 are tragic and I have far too many friends who have experienced one or the other. To protect the feelings of those who have suffered these tragedies, I will not name them. But I will give the following first-hand examples of #3 (with permission) – all three of these dogs were diagnosed accidentally as a result of unrelated events:

Jasmine, my own 13-yr-old, had a frightening vestibular event (i.e. doggy vertigo) a few weeks ago. I have since learned that this is a rather common idiopathic condition in older dogs, but the neurologist that examined her determined that she wasn’t “classically vestibular”. In pursuing a differential diagnosis, an abdominal ultrasound was performed revealing a large abdominal mass. Urgent exploratory surgery resulted in the excision of a “fully-encapsulated splenic mass with no evidence of other organ involvement.” Final pathology results are still pending, but the preliminary assumption is that the surgery was curative. There is additional background to this story as you’ll see below.
My friend Sarah, who specializes in canine rehab and massage, was routinely massaging her 14-yr-old Cruiser one night and felt a bulge under her rib cage. This lump was only apparent to sensitive hands and only when the dog was on her back. On examination, her doctor couldn’t even feel it but abdominal ultrasound revealed a splenic tumor which was then surgically excised. The dog lived another great year and eventually succumbed to complications of unrelated kidney failure.
Just last week, my friend Liza’s 7-yr-old Taiko had an intestinal obstruction that required emergency surgery. While his belly was open, the surgeon observed a nodule on the spleen and elected to perform a splenectomy. Pathology report on the lesion suggested that it would have likely transformed into a splenic tumor (probably hemangioma) had it gone undetected.

Here’s a little more background on Jasmine’s story: in April of 2008, she spent a couple of days at Davis for a bout of hemorrhagic gastroenteritis (HGE). During her stay she had an abdominal ultrasound. They found nothing to explain the HGE, but did note some other abnormalities: a cyst on the liver and two nodules on the spleen. We were advised to follow up with another ultrasound in about a year. So we did. A scheduled ultrasound in June 2009 reported that the liver cyst was unchanged and the two splenic nodules were nowhere to be found. Excellent news, or so we thought. Not long after that I began having theoretical discussions with friends about the merit of routine ultrasounds, but we didn’t bother to do another one in the summer of 2010. Fast-forward to February 2011 and the crisis described above.

I found a terrific article that explains in much more detail what I’m talking about: http://www.marvistavet.com/html/body_splenic_masses.html. The most telling quote for me in this article is this: “[If the dog has a splenic mass and you choose not to remove the spleen], eventually the dog will have a bleed from which he cannot recover.”

So what’s my point? Dogs die from splenic masses, often unnecessarily. It doesn’t matter whether they are malignant or benign. Sure, malignant masses affect other organs and the dog will eventually die anyway. But benign doesn’t mean harmless, it just means non-cancerous – benign tumors can still grow like crazy and rupture. In fact, I learned a parodoxical reality: the larger the splenic mass, the more likely it is benign because the dogs don’t survive the malignant ones long enough for them to grow large. Regardless of size or type, ALL splenic masses have the potential to rupture and cause death from hemorrhage. They are ticking time bombs, pure and simple. Isn’t it time we acknowledge this fact and start preemptively screening for the problem?

Lessons learned:

Splenic nodules do not just disappear. I don’t know where Jasmine’s were in June 2009, but I’m sure now that they were lurking somewhere.
Splenic nodules transform, and nothing good comes from that transformation. Even if they transform into benign masses, they can still rupture and cause catastrophic hemorrhage.
If at all financially-feasible, we should consider doing annual diagnostic ultrasounds on our aging dogs to avoid these tragedies. They are non-invasive and require only a mild sedative (if even that).

I have a mammogram every year, and I’m going to do my best to ensure that my older dogs get the same consideration.

11 Comments | Splenic Tumors | Permalink
Posted by agilepooch

Mast Cell Tumors, part 2

July 10, 2009

Mostly good news. We got the cytology report today, and Jasmine’s mast cell tumor (MCT) has the following characteristics:

Grade II. We would have rather had Grade I, but this is still much better than Grade III.
Well-differentiated. This is a term that is more commonly associated with Grade I (in contrast to moderately- or poorly-differentiated). So maybe this means we’re on the low side of Grade II. I’m going to go with that.
Clean margins in all directions, including underneath. Thanks to our surgeon for being so thorough, and to Sarah for helping us find it so early.
Low Mitotic Index (MI). This may be the most important thing. According to a UC Davis study, “MI is a strong predictor of overall survivalfor dogs with cutaneous MCTs and should be included as a prognosticindicator when determining therapeutic options.”

Bottom line: no further treatment is indicated or recommended. The doctor also reassured us that skin MCTs don’t usually progress to the internal organs – those more commonly just start there. And since she had an abdominal ultrasound just a few weeks ago (completely unrelated) that cleared both her liver and spleen, I think we’re in pretty good shape on that.

So, a big sigh of relief, at least for now. And now we implement a more aggressive schedule of body checks on all of the dogs – to include the limbs. Until now, we have focused more on the torso because that’s where the lipomas tend to crop up. The key to these MCTs is to catch them early and get them the heck outta there.

Again, thanks to all of my friends for the well-wishes. And thanks also to our vets at North Park Veterinary Clinic in Rohnert Park, especially Dr. Miconi who diagnosed the MCT and is doing the follow-up, and Dr. Schweid who performed the surgery.

Jasmine the pirate queen in her "half-pants".

Another view of the pirate pants.

1 Comment | Mast Cell Tumors | Permalink
Posted by agilepooch

Mast Cell Tumors, Part 1

July 8, 2009

Well, based on the encouragement of two friends named Ellen, I decided to start a blog. I didn’t expect my first post to be such a serious topic. But here we are.

Last Sunday, after a perfect Standard run, Jasmine was getting a cool-down massage from my friend, Sarah Johnson. She (Jasmine) is prone to harmless lipomas, and Sarah and I had talked about two new ones that had recently popped up on her abdomen. As Sarah was massaging her, she discovered a lump on her hind leg. Confused by the location, she asked me if this was one of the new lipomas. YIKES, NO!!! Lipomas are loose smooth lumps under the skin that are barely noticeable unless you happen to feel them. This thing was a horrible, discolored fleshy mass about the size of a cherry that protruded through the fur. But it was buried in her hock feathers, so was not immediately apparent until it was discovered by palpation.

After consulting with friend and RVT, Katrina Parkinson, I learned that I should leave the mass alone until it could be examined by a vet. If it did turn out to be a mast cell tumor, apparently they can get angry with the least provocation and produce a huge release of histamines that can lead to anaphylactic shock. Don’t mess with it – got it!

With this new distraction, I botched my timing on her Gamblers close, but she pulled off decent runs in Pairs and Jumpers. We packed up and headed home, hoping that a trip to the emergency room would yield an easily-treatable foxtail abcess. When we arrived at home, we called our local emergency clinic, and not recognizing the name of the doctor on duty, we waited until 7pm until our “regular” doctor showed up. Why do we have a “regular” doctor at the emergency room? Because it seems that over the last couple of years, all of our dogs tend to get in trouble on Sun-Tues between 7pm and 7am. But I digress.

We arrived just after 7pm, shortly before all hell broke loose and our preferred doc got tied up with traumas and allergic reactions. We were greeted by the day doc, who is not on the regular staff (holiday weekend coverage, I guess). He had the bedside manner of a Mack truck, and apparently, the diagnostic skills to match. We were left with words to the following effect: It’s not a foxtail, we’ll send the smear out for cytology review, you need to follow up right away with your regular vet, and there’s nothing palliative for us to do tonight. Yes, he actually used the word “palliative”. How do you think that made us feel? Cha-ching, no answers and nothing but worry for us.

Monday morning, we decided to start over with our regular vets at North Park Veterinary Clinic. Apparently, Dr. Miconi’s skills with a smear and microscope are better honed, as she immediately recognized the aspirated cells as consistent with mast cell tumor. I suppose it helps that her own dog has a long history of these things. She advised immediate surgical removal, and since they were able to fit her in the schedule that day, that was that. Fortunately, we had anticipated this outcome and hadn’t fed the dog that morning so she was good to go.

We picked her up at 4pm with a bit of a hangover and a 7″ incision from ankle to thigh. The goal with mast cell tumors is to clear a 2-3cm margin on all sides because the tumors are generally poorly differentiated. That is a little tricky on the leg (at least horizontally) because they have to do a balancing act between excising enough tissue to be safe, and leaving enough skin to close the wound. As a result, the skin is very tight and we have to limit her activity so it doesn’t tear.

In the meantime, I have learned a little more about mast cell tumors. Once the tumor tissue is removed, it is sent to a pathologist for grading and staging. Grading is the key, as the grade (I-III) determines the aggressiveness of the tumor and how likely it is to be malignant. Grade I means that no further intervention is required and we just need to watch out for new tumors. In addition, the staging (0-IV), as we probably all know from human cancers, is an indication of how far the tumor cells have spread through the body. So now we wait, and hope for Grade I. The pathology results take 4-6 days, which means we should know more by Friday.

In the meantime, here’s a nice photo of her incision. I wish I had a picture of the original tumor, but it didn’t occur to me until too late.

Incision from removal of cherry-sized mast cell tumor

Thanks to our friends at Drs. Foster and Smith (one of my favorite online vendors) for providing PetEducation.com, the source of referenced articles in this post for both lipomas and mast cell tumors. And thanks also to all of the kind words and well wishes that my friends have sent me through Facebook and e-mail.