Gulp: Adventures on the Alimentary Canal (35 page)

The nurse admires a platter of chocolate-covered whole bananas, one of the thematically appropriate desserts created by Khoruts’s thirteen-year-old. James is very much his father’s son, intelligent and cultured, with a sly sense of humor. He plays classical music on the grand piano in the living room and would like to write novels one day. The nurse asks James what number the desserts
^*
would be on the Bristol Stool Scale. He replies without hesitating—4 (“like a sausage or snake, smooth and soft”).

It’s tough to find an inappropriate mealtime conversation with this group—not because they’re crass or ill-mannered, but because they view the universe of the colon very differently than the rest of us do. The interactions between the human body and its gut microbiome—as our hundred trillion intestinal roomers are collectively known—is a hot research area of late. For decades, medical investigators have looked at the role of food and nutrients in disease treatment and prevention. That has begun to seem simplistic. Now the goal is to tease apart the interactions between the body, the food, and the bacteria that break down the food. One example is the cancer-fighter du jour: the polyphenol family, found in coffee, tea, fruits, and vegetables. Some of the most beneficial polyphenols aren’t absorbed in the small intestine; we depend on colonic bacteria to metabolize them. Depending on who’s living in your gut, you may or may not benefit from what you eat. Or be harmed. Charred red meat has long been called a carcinogen, but in fact it is only the raw material for making carcinogens. Without the gut bacteria that break it down, the raw goods are harmless. (This applies to drugs too; depending on the makeup of your gut flora, the efficacy of a drug may vary.) The science is new and extremely complex, but the bottom line is simple. Changing people’s bacteria is turning out to be a more effective strategy for treatment and prevention of disease than changing their diet.

As a member of a culture that demonizes bacteria in general and the germs of other people in specific, you may find it disturbing to imagine checking into a hospital to be implanted with bacteria from another person’s colon. For the patient I’ll shortly be meeting, a man invaded by
Clostridium difficile
, it’s a welcome event. Infection with chronic
C. diff
—to use the medical nickname—can be an incapacitating and sometimes fatal illness.

“When you’re fifty-five years old and you’re wearing diapers that you’re changing ten times a day,” Matt Hamilton says, “you’re numb to the ick factor.” He lifts some stuffed tomatoes to his plate. Matt has the forceful, unabashed appetite of the big, young male.

“For the patient, there is no ick factor,” Khoruts adds. “They’ve been icked out. It’s a chronic disease and they just want to be rid of it.”

As regards bacteria in general, a radical shift in thinking is under way. For starters, there are way more of them than you. For every one cell of your body, there are nine (smaller) cells of bacteria. Khoruts takes issue with the them-versus-you mentality. “Bacteria represent a metabolically active organ in our bodies.” They
are
you. You are them. “It’s a philosophical question. Who owns who?”

People’s bacterial demographics are likely to influence their day-to-day behavior. “Certain populations in the gut may want you to eat a certain kind of diet or to store energy differently.” (A clinical trial is under way in the Netherlands to see if transplants of “donor feces” from lean volunteers will help subjects lose weight;
^*
thus far results are encouraging but undramatic.) Khoruts gave me a memorable example of how behavior can be covertly manipulated by microorganisms. The parasite
Toxoplasma
infects rats but needs to make its way into a cat’s gut to reproduce. The parasite’s strategy for achieving this goal is to alter the rat brain such that the rodent is now attracted to cat urine. Rat walks right up to cat, gets killed, eaten. If you saw the events unfold, Khoruts continued, you’d scratch your head and go, What is wrong with that rat? Then he smiled. “Do you think Republicans have different flora?”

What determines your internal cast of characters? For the most part, it’s luck of the draw. The bacteria species in your colon today are more or less the same ones you had when you were six months old. About 80 percent of a person’s gut microflora transmit from his or her mother during birth. “It’s a very stable system,” says Khoruts. “You can trace a person’s family tree by their flora.”

The party is winding down. I go into the kitchen to say good night to James and to Khoruts’s mirthful, tolerant girlfriend, Katerina. A blender sits on the counter by the sink, waiting to be washed. “Hey,” says James. “You missed the chocolate poop smoothies.”

That’s okay, because I’ll be seeing the real thing.

• • •

L
IKE ANY TRANSPLANT,
it begins with a donor. “Anyone’s will do,” says Khoruts. He has no idea which bacteria he’s after—which are the avenging angels that bring
C. diff
under control. Even if he knew, there’s no simple way to determine whether those species are present in a donor’s contribution. Most species of fecal bacteria are tough to culture in the lab because they’re anaerobic, meaning they can’t live in the presence of oxygen. (Common strains of
E. coli
and
Staph
bacteria are exceptions. They thrive inside people and out, on doctors and their equipment, and everywhere in between.)

The only thing Khoruts requires of donors is that they be free of digestive maladies and communicable diseases. Family members are not the most desirable donors because their medical questionnaire may not be entirely truthful. “You wouldn’t necessarily want to reveal to your loved ones that you’ve been visiting prostitutes.” Khoruts is partial to the donations of a local man who, understandably, wishes to remain anonymous. This man’s bacteria have been transplanted into ten patients, curing all of them. “His head is getting bigger,” deadpans Khoruts. Most of what Khoruts says is delivered deadpan. “In Russia,” he told me, “if you smile a lot, they think something’s wrong with you.” He has to remind himself to smile when he talks to people. Sometimes it arrives a beat or two late, like the words of a far-flung foreign correspondent reporting live on TV.

“Here he is.” A tall man, dressed for a Minneapolis winter, lopes down the hallway carrying a small paper bag.

“Not my best work,” the man says, nodding hello to me as he hands Khoruts the bag. With no further chitchat, he turns to leave. He does not seem embarrassed, just pressed for time. He’s an unlikely hero, quietly saving lives and restoring health with the product of his morning toilet.

Khoruts slips into an empty exam room and dials Matt Hamilton’s number. On the morning of a transplant, Matt will stop by the hospital on his way to the Environmental Microbiology Laboratory, where he works and the material is processed. He’s usually here by now, and Khoruts is feeling antsy. Anaerobic bacteria outside the colon have a limited life span. No one knows how many hours they can survive.

Khoruts leaves a message: “Hi, it’s Alex. The stuff is ready for pickup.” He squints. “I
think
that’s his number.” It would be a provocative message to receive from a stranger. I picture narcotics officers storming the gastroenterology department, Khoruts struggling to explain.

Khoruts has barely hung up when Matt hustles in, all polar fleece and apology. Matt smiles as naturally as Khoruts doesn’t. I imagine it is almost impossible to be peeved at Matt Hamilton.

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.”

L
IKE 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.

The lights are dim and a stereo plays classical music. Khoruts makes conversation to gauge the sedative’s effects. He’s listening for a quieting of the voice, a slowing of words. “Do you have any pets?”

The room is quiet for a moment. “. . . pets.”

“I think we’re ready to go.”

A nurse brings the bowl with the vials. I ask her if the red color of the caps on the vials signifies biohazard.

“No, just the brown color inside.”

Unless one is watching closely, a fecal transplant looks very much like a colonoscopy. The first thing to appear on the video monitor is a careering fish-eye view of the exam room as the scope is pulled from its holder and carried over to the bed. If you are young enough to be unfamiliar with a colonoscope, I invite you to picture a bartender’s soda gun: the long, flexible black tube, the controls mounted on a handheld head. Where the bartender has buttons for soda water and cola, Khoruts can choose between carbon dioxide, for inflating the colon so he can see it better, and saline, for rinsing away remnants of an “inadequate prep.”