Gulp: Adventures on the Alimentary Canal

The lab is ten minutes by car. Because Matt is driving fast and the cooler keeps threatening to slide off the backseat, there’s a mild tension in the car. The cooler is a tangible presence, somewhere between groceries and an actual passenger. Soon we’re circling, looking for parking. Matt resents the waste of time. “If I had organs, they’d give me a parking pass.”


The parking turns out to take longer than the processing. The equipment is simple: an Oster* blender and a set of soil sieves. The blender lid has been rigged with two tubes so that nitrogen can be pumped in and oxygen forced out. Two or three 20-second pulses on the liquefy setting typically does the trick, and then it’s on to the sieves. For obvious reasons, everything is done under a fume hood. Matt chats as he sieves, occasionally calling out a recognizable element: a chili flake, a piece of peanut.*

A decision is made to do a second run through the blender. If the material doesn’t flow freely, it can clog the colonoscope and compromise the microbes’ spread through the colon. He turns to face me. “So today we’ve kind of been confronted with what to do when it’s a hard, solid chunk rather than an easier mix.” It’s like American Chopper when Paul Sr. or Vinnie addresses the camera to give a summary of what viewers have been seeing.

Finally the liquid is poured into a container with a very good seal and returned to the cooler. It looks like coffee with low-fat milk. There is almost no smell, the gases having all gone up the fume hood. The three of us, Matt and I and The Cooler, hurry back to the car and retrace our route to the hospital.


The transplant patient has arrived. He waits on a gurney in a room made by curtains. Khoruts is in the hallway in his white coat. Matt hands him the cooler. He fills and caps four vials that will be pumped into the patient through the colonoscope. For now, they are laid on ice in a plastic bowl. Khoruts asks a passing nurse where he can leave the bowl while he waits for an exam room to open up. She glances at it, barely breaking stride. “Just don’t bring it in the break room.”

LIKE PEOPLE, BACTERIA are good or bad not so much by nature as by circumstance. Staph bacteria are relatively mellow on the skin, presumably because there are fewer nutrients there. Should they manage to make their way into the bloodstream via, for instance, a surgical incision, it’s a different story. Receptors and surface proteins allow bacteria to “sense” nutrients in their environment. As Matt puts it, “They’re like: ‘This is a good spot, we should go crazy in here.’” Gut microflora party! Bad news for the host. Strains found in hospitals are more likely to be antibiotic-resistant, and hospital patients are often immunocompromised and can’t fight back.

Likewise E. coli. Most strains cause no symptoms inside the colon. The immune system is accustomed to huge numbers of them in the gut. No cause for alarm. Should the same strain make its way to the urethra and bladder, now it’s perceived as an invader. In this case, the immune attack itself creates the symptoms—in the form, say, of inflammation.

Even C. difficile is not inherently bad. Thirty to fifty percent of infants are colonized with C. diff and suffer no ill effects. Three percent of adults are known to harbor it in their gut without problems. Other bacteria may tell it not to make toxins, or the numbers are too small for the toxins to create noticeable symptoms.

The problems often begin when a colon is wiped clean by antibiotics. Now C. diff has a chance to gain a foothold. As careful as hospitals try to be, C. diff spores are everywhere. And certain conditions in the colon make it easier for C. diff to thrive. Diverticuli are pockets along the colon wall, often created by chronic constipation. Like this: If the muscles of the colon have to push hard to move waste along and there’s a weak spot in the wall, the matter will follow the path of least resistance. The weak spot will balloon outward and form a small pocket. C. diff spores seed the pockets.

Eighty percent of the time, antibiotics clear up a C. diff infection. Twenty percent of the time, it comes back within a week or two. The C. diff entrenched in diverticuli are tough to annihilate; they’re the Al Qaeda of the GI tract, hiding out in inaccessible caves. “Antibiotics are a double-edged sword,” says Khoruts. “They suppress C. diff, but they also kill the bacteria that keep it under control.” Every time the patient has a relapse, the chance of another relapse doubles. Infections with C. diff kill around sixteen thousand Americans a year.

Today’s patient has diverticuli that became abscessed. Multiple severe bouts of colitis have caused diarrhea so severe he has had, at times, to be fed intravenously. You wouldn’t guess any of this to look at him now, in the exam room. He has been given Versed, an antianxiety medication. He lies calmly on his side in a blue and white johnny with no pants. There is a heartbreaking vulnerability to people having hospital procedures. They may be CEOs or generals on the outside, but in here they are just patients, docile, hopeful, grateful.

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