Posted Feb 19, 2013
Thirty years ago, Andrew Goldberg encountered the Earwax Man.
As a young intern in Pittsburgh training to be an ear, nose and throat physician, Dr. Goldberg met a middle-aged patient who had recurring infections in one ear.
Dr. Goldberg and his colleagues would give him antibiotic drops, and the problem would go away. But then it would come back — until one day, when the man walked in and claimed the infection had disappeared.
“We just assumed that one of our myriad drop regimens had finally hit its mark and wiped out the guy’s bacteria,” said Dr. Goldberg, who now oversees sinus surgery at the University of California at San Francisco Medical Center.
The man knew otherwise. “You see,” he told the doctors, “I figured, I have one ear that’s bad and one ear that’s good, and whatever’s in my good ear I want to get over to my bad ear, so I just took some wax from my good ear and put it in my bad ear and within a couple days, I was fine.”
The Human Microbiome
Dr. Goldberg just laughed uncomfortably at the man’s explanation back then. But today, he believes the patient was right: By putting earwax from one ear into the other, he was also transferring the bacterial colonies from the healthy ear into the sick one, and that probably cured his persistent infections.
This strange story is now a legend in the fast-growing field known as the human microbiome — the study of the trillions of bacteria that live inside us and the critical role they play in our health and in many of our diseases.
In recognition of their importance, the National Institutes of Health has established the Human Microbiome Project, an ambitious effort to comprehensively catalog the microbes living in several parts of our bodies. There is also research going on at labs around the world to investigate what role bacteria might play in several chronic diseases, and there’s even a quirky educational venture in North Carolina known as Belly Button Biodiversity.
Here’s a look at just a few of the microbiome projects.
Chronic sinus infections
Dr. Goldberg’s latest research focuses not on ears, but sinuses.
Like his Pittsburgh patient, many people with chronic sinus infections can’t get rid of them despite repeated doses of antibiotics and cleanouts of the infected cavities, which sit behind the nose, cheeks, eyes and forehead.
Using new genetic analysis techniques, Dr. Goldberg and his colleagues found in a study published last year in Science that 10 patients with recurring infections had about 300 fewer species of bacteria in their sinuses than 10 healthy patients did — 900 vs. 1,200.
They also found the sick patients had depleted ranks of a benign species of bacteria known as Lactobacillus sakei, and elevated populations of a species known as Corynebacterium tuberculostearicum.
The findings were made possible by a new tool called the PhyloChip, which allowed researchers to analyze the genetic material of all the bacteria taken from the patients, instead of just the species that were able to grow in the laboratory.
Often, only a handful of all bacteria in a sample can grow in a laboratory dish, Dr. Goldberg said, and “who’s to say that what grows on an agar plate is the most important bacterium in that environment?”
Infectious disease specialists used to think persistent bacterial infections were caused by biofilms — gooey layers that shielded the bacteria from antibiotics.
“The idea was that if we could just kill the hiding bacteria, everything would be fine,” he said. “But that’s clearly only part of the issue, because if you don’t reconstitute a [healthy bacterial] environment that will be self-sustaining, you’re right back to your old problem.”
Dr. Goldberg’s team found that mice infected with the C. tuberculostearicum species could be cured by giving them the helpful L. sakei strain, which kept the harmful bacteria in check.
One day, he believes, similar “probiotic” treatments with beneficial bacteria might be used to cure chronic sinus infections in people.
The microbiome-based treatment that has received the most publicity is fecal transplants to cure chronic intestinal infections caused by the Clostridium difficile bacteria.
Despite the “ick factor,” the transplants, in which a doctor puts liquefied feces from a healthy donor into the intestines of a sick patient, have been incredibly successful.
In a study last month in the New England Journal of Medicine, European doctors found that 13 of 16