Ask the doctors 9/19

Dear Doctor: What on earth is a “gutoscopy”? We saw it on the news – something about a pill that goes in one end and comes out the other, but it sounded more like science fiction than anything real.

Dear Reader: Your question brings us to the brave new world of what are sometimes referred to as “smart pills.” These are tiny devices, small enough to be swallowed, that perform a range of functions as they move along the gastrointestinal tract. This can include the precision delivery of medication and the collection of different types of data.

Certain types of smart pills are equipped with biosensors, pH and chemical sensors, or imaging capabilities. Classified as ingestible sensors, they can be used to collect information such as pressure readings, pH and temperature data. The data they gather can shed light on the workings of the stomach, small bowel and colon. Rather than an invasive procedure that requires surgery or an instrument threaded through a catheter, the patient swallows a capsule that contains the miniature sensor. The device then transmits its findings to a computer.

Some types of smart pills are engineered to collect samples from inside the body for study and analysis. That’s the case with the “gutoscopy” device you’re referring to in your question. Developed several years ago by researchers at Purdue University, the team published a paper about its findings earlier this year. Their goal was to devise a noninvasive method to learn more about the billions of microscopic organisms that live within the human gut.

Research continues to link the workings of the gut microbiome to an ever-expanding array of biological functions and health conditions. This includes obesity, diabetes, mood, digestive disorders, cardiovascular health and certain cancers. The composition of the gut microbiome has also been linked to various neurological diseases, including Parkinson’s disease, multiple sclerosis, autism spectrum disorder and Alzheimer’s disease.

The “gutoscopy” capsule, which is still in the research phase, is made of nontoxic 3D-printed resin. It’s formulated to dissolve at a specific pH within the gut. This allows the release of a “thirsty” gel, similar to that used in moisture-absorbing pads and diapers. The hydrogel collects gut bacteria from the fluid of the intestine. The capsule is designed to travel the length of the bowel, carried along by the natural wavelike contractions of the digestive process. It collects samples as it goes, until a change in pressure forces the capsule to close. The device passes from the body in a bowel movement. Researchers can then open the capsule, collect the gel and analyze the array of gut flora that it contains.

Unlike existing diagnostic tests, such as a colonoscopy or an endoscopy, this new capsule can travel the entire length of the gut, and it wouldn’t have to be administered in a clinical setting. The goal is to learn more about the diversity of microorganisms living within the gut. That information can help researchers better understand disease processes, and craft medications and therapies.

Send your questions to askthedoctors@mednet.ucla.edu.