Inflammatory Bowel Disease part 2

Posted by Aaron

Thursday, March 4, 2010

Here's how I approach a case of chronic vomiting or diarrhea and what would be required to answer ALL possible answers. Think through this list when you go to your veterinarian (starting at item one - don't skip ahead) and it can help aid in the diagnosis tremendously - ESPECIALLY the historical findings.
  1. First things first - a good history. When does the diarrhea and vomiting happen? Is there any kind of temporal connection? Travel? Diet change? What about weight loss or gain? Is the vomiting immediately after a meal? First thing in the morning on an empty stomach? Is the diarrhea characterized by sudden urgency or constant straining? Did the vomiting or diarrhea respond to previous treatments? If so, what treatments and in what way did it respond? Did the problem resolve and then recur, or did it only resolve while ON the medications? What other medications is the patient on? What foods do the other animals in the house eat? Does this pet eat the other pet's food (either before it's eaten or after it's pooped out - IOW is your dog a poo-eater?)? Is your pet also having urinary problems? What breed(s) is your pet? All of these things help narrow down the list of likely suspects.
  2. Physical exam. Weight gain? Weight loss? How does the abdomen feel on palpation? Is the pet dehydrated? How does the patient "as a whole" look? Does the patient have other diagnosed problems that could be causing this problem? Are there any lumps or bumps that would cause concern? How does the anus and rectum feel on examination? Is there lots of gas? Constipation?
  3. Examine the poo. As was said on one of the funniest episodes of the sitcom Scrubs, "If you want to know what's wrong with you, it all comes down to Number 2!" Seriously, though, the poo can tell us a lot. This would be the best way for us to identify most parasites. Not all parasites can be found at all times, and fecal exams are never 100% sensitive. Repeat fecal exams at different times and on GOOD SIZED samples is critical. I get totally chapped when I see people take these little, itty, bitty, tiny samples and then declare that "the fecal is negative." NO NO NO. You must take a good sized sample, use good technique in your fecal examination, and then you can declare that "no parasites were seen." Seems like I'm splitting gnat weenie hairs, but it's a big distinction. No whipworms today doesn't mean much. They're a booger to find on a good day. Most would agree that you need a total of 5 fecals done on 5 different days to say that there are no whips present. Many times, submitting the stool to the lab for advanced diagnostics is smart. The labs can now look for parasite DNA in many cases and this makes the test very sensitive. You still have to submit a LARGE ENOUGH sample. You want to know how to make your veterinarian's job easier and help get a proper diagnosis? Bring stool with you! Fresh, stinky, warm poo makes me happy to see. Now I've got a big sample and I don't have to go fishing for it. It drives me crazy when someone come in with a complaint of stool problems, but then doesn't bring a sample.
  4. Basic blood workup. Look at my previous post on this one. We're looking for things like increased eosinophils (allergic reaction), low albumin (loss of protein), changes in cholesterol (poor absorption), abnormal lipids (funky fat absorption) and such.
  5. Gastrointestinal specific bloods include things like a "pancreatitis test" also known as a Spec cPL, Trypsin Like Immunoactivity (TLI), cobalamine, and thiamine. These each help identify if there is evidence of chronic mal-absorption and tell us more about if the pancreas is functioning normally.
  6. Endoscopy or abdominal exploratory surgery. The idea here is that we may need to LOOK at the gut and take biopsies to get a diagnosis. Endoscopy/colonoscopy is where we drive a camera down or up (depending on the end you start at :) ) and it allows you to see the lining of the gut. You can look for ulcerations, polyps, thickening, and any number of abnormalities. You can also use a little biopsy tool to take a tiny piece of the lining of the gut. The major benefits of endoscopy are 1) You get to see the inside of the gut up close and personal, 2) you don't have to open up the abdomen, and 3) it gives you nice biopsy samples that are only partial thickness - there's less of a defect to heal. The major downsides are 1) you can only get SO far down or up before you just can't get any farther with the camera. This means that there are large lengths of bowel you can't see. You will, therefore, totally miss problems if they are segmental and the segment that's a problem is out of reach. 2) the biopsy taken is only partial thickness. This means that you miss some of the deeper tissues. You may, therefore, miss out on part of the diagnosis. However, it should be noted that endoscopic biopsy is nearly always diagnostic, but it's not 100%. The major benefit of abdominal explore is that you can run the ENTIRE gut and can take full-thickness biopsy. The major disadvantages are that you can't see the INSIDE of the gut (major disadvantage), and you actually have to open up the belly (not a huge deal, but there is more healing involved).
  7. There is NO way to diagnose IBD properly without biopsy samples. IBD is a diagnosis made using the microscope AND the rest of the physical exam and bloodwork findings. Biopsy is also the only way to try and differentiate between things like lymphocytic lymphoma (tumor in the gut) and true lymphoplasmacytic inflammatory bowel disease in cats. In other words, is this cancer or is this just inflammation.
  8. Ultrasound of the abdomen. This can be considered in lieu of the endoscopy or explore, but it isn't the kind of thing that allows you to visualize how the inside of the gut looks and it is impossible to get biopsy samples of the gut. You can often times get aspirates and those may be diagnostic. Ultrasound is typically used if we have a patient that is a poor anesthesia risk or if we happen to be ultrasounding for some other reason and can try to get information on the gut as well. Ultrasound does have a great benefit from being able to measure the thickness of the bowel.
  9. Bacterial cultures of the gut. These have varied applications. There are lots of arguments both for and against cultures and what they mean. If I find salmonella, is that bad? Just how many bacteria in the small bowel are TOO many? If I don't find campylobacter on a culture, does that mean it's not there? I believe that bacterial cultures aren't used as much as they could be because we don't always know what to do with the results.
Do I expect an owner to be willing or able to do ALL 9 of these items? Nope. Most people flat out can't even consider it. In fact, it's overkill to even try and do all 9 items at once. We may eventually get through all 9, but we always start with the first few, then treat, then think, then move forward.

Next post - treatment options.



Hege said...

Hi Dr. Herndon! It's been a long time! Not sure if you remeber me... I'm Cairo's owner. You helped get Cairo diagnosed with hypothyroid issues a few years back (you also wrote a case study on her). We also talked after her TPLO surgery a year and a half ago. Anyway, Cairo is having some issues with her tummy (and also her appetite, which is very unlike her...she's always had a somewhat sensitive tummy, but NEVER refused food!). So I went online to look to see if you were still in the DFW area, because we would love to have you as our vet again. Are you?

Aaron said...

Yes I remember you! It's wonderful to hear from you and get an update on Cairo!

I'm actually in Oklahoma now doing a PhD and Internal Medicine Residency at Oklahoma State. E-mail my work address aaron.herndon(at) I'd love to help you out if I can! At the very least I can help get you somewhere that can help.

Hope to hear from you soon!