January 29, 2020

Parasites & The Importance Of Finding The Root Cause

A few years ago, a very nice woman named Lucy came to see me about some symptoms she was having. From the beginning she was convinced she had a parasite, and her story is in many ways, representative of the trials and tribulations of figuring out whether that may indeed be the case.

Lucy had seen a number of gastroenterologists before me, and reading between the lines of their notes in her medical records, I could see they thought she was a little bit intense. She was a little bit intense, and rightly so. I would have been, too, if my life had been turned upside down by symptoms that no one could explain and that weren’t getting any better.

In addition to bloating, she was also having fatigue, upper abdominal pain, nausea, and what she described as “weird” stools. The first gastroenterologist Lucy saw did an upper endoscopy, thinking it might be acid reflux. The exam was normal other than a little redness in the stomach, which doctors often call “gastritis,” which suggests inflammation of the stomach. But gastritis usually responds to treatment, and after being treated with acid suppressive medication for four weeks, Lucy was no better. When stool studies for ova (eggs) and parasites came back negative from the first lab, I asked Lucy to use Popsicle sticks to scrape her stool into jars and send it off to a specialty lab in Arizona with an excellent track record for diagnosing parasites. When that lab didn’t find anything unusual, we went ahead with a colonoscopy, with multiple biopsies in every segment to check for microscopic evidence of inflammation. When those biopsies came back normal, it was time to extend our investigation to the small intestine.

It can be hard to reach all twenty feet of small intestine between the stomach and colon; it’s too long to completely examine with a traditional endoscope, but there are some novel ways to get a good look at it. A video capsule endoscope is a tiny capsule that packs a lot of punch—a camera, light source, radio transmitter, semiconductor, and an eight-hour battery— all in a pill the size of a large vitamin that’s swallowed and flushable when it’s excreted out the other end. One of my favorite tasks at work is reviewing the images obtained from the capsule as it travels through the intestines taking two pictures per second of everything in its field of view and condensing it into an incredible Fantastic Voyage video. Lucy’s video showed image after image of unremarkable small intestine.

We had now examined her entire digestive tract, from her mouth to her anus, and it all looked normal. I decided to cast a broader net to explore whether the problem could be inside her abdomen but outside her intestines. But a CAT (computerized axial tomography) scan and MRI (magnetic resonance imaging) showed normal abdominal organs. Then I thought maybe the organs might look normal but not be working properly, so I ordered a scan to see how her gallbladder was functioning. When that came back normal, I ordered a gastric emptying study: a test where they give a person radio-labeled food to eat and then scan over the stomach to see how long it takes to empty. If a significant percentage of the meal is still in the stomach at the completion of the test, that’s considered diagnostic for delayed emptying, a condition called gastroparesis, that can cause bloating, pain, and nausea. That was normal, too.

Although neither of us wanted something to be wrong, we both knew something was, and we were desperate to find it. In the meantime, I asked Lucy to jump through a number of dietary hoops to see if any of them led to an improvement in her symptoms: gluten-free, dairy-free, no refined sugar, fructose-free, low-fat, no fat. She dutifully tried them all, to no avail.

During a visit to discuss all the tests we’d done, Lucy pulled out some photographs of her stool. There seemed to be an oily sheen to them, and she mentioned that some of them floated. While she didn’t have any compelling reason for her pancreas to not be working properly, her stool and her symptoms fit the bill: oily-looking, foul-smelling stools that floated, crampy abdominal pain, bloating, and low-grade nausea—all symptoms consistent with a diagnosis of pancreatic insufficiency. I gave her a prescription for pancreatic replacement enzymes, feeling sure we had finally cracked the case. No dice.

At a loss for what to do next, I asked Lucy to send one final set of stool specimens to the lab of a local infectious disease specialist who had a lot of expertise in parasitology. Lo and behold, they were positive for Cyclospora, a tiny one-celled organism transmitted by ingesting contaminated food or water, and best known for the 1996 outbreak associated with stool-tainted raspberries from Guatemala. Cyclospora usually causes diarrhea that can persist for several weeks. Additional symptoms include bloating, low-grade fever, abdominal craParasitmping, poor appetite, weight loss, increased flatulence, vomiting, and fat malabsorption that results in oily, floating stools. Relapses are common if untreated.

Lucy finally got diagnosed, not because of my amazing diagnostic skills (it certainly took me long enough!), but because we both believed that something was wrong and were willing to roll up our sleeves and find it.