Righting a man’s microbial wrongs stopped his body from producing intoxicating amounts of alcohol

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A man in Massachusetts whose gut started brewing its own alcohol, which made him heavily intoxicated, has finally recovered after swallowing multiple doses of bacteria from a healthy person’s faeces.

The man, a retired US Marine officer in his 60s, started experiencing odd symptoms after taking multiple courses of antibiotics to treat an inflamed prostate. He had been fit and healthy, and had only an occasional alcoholic drink, but he suddenly began feeling very drunk, disoriented and sleepy on a regular basis.

The man visited the emergency department on several occasions, but no one believed he hadn’t been drinking. Eventually, he was diagnosed with auto-brewery syndrome, a rare condition in which microbes in the gut produce large amounts of alcohol.

His severe intoxication made it difficult to perform his normal daily tasks. He also had to have a breathalyser lock installed in his car to ensure he didn’t drive while over the limit.

After connecting with a patient support group, the man learned that faecal transplants were being considered as a potential treatment for auto-brewery syndrome. This inspired him to call Elizabeth Hohmann, a physician who conducts faecal transplants at Massachusetts General Hospital. “He kept leaving messages on my voicemail and he sounded intoxicated, so I kept trying to ignore them,” she says.

Eventually, the man’s wife called Hohmann and explained the situation. Hohmann discussed the case with Bernd Schnabl, a gastroenterologist and auto-brewery syndrome expert at the University of California San Diego. Together, they agreed to trial a faecal transplant in the man.

Before conducting the transplant, Hohmann, Schnabl and their colleagues conducted the most in-depth study yet of people with auto-brewery syndrome to investigate its causes. They studied stool samples from 22 people with the condition and 21 household partners to see whether they had different kinds of gut microbes. “Our lab was a little bit smelly,” says Schnabl.

The team found that stools from people with auto-brewery syndrome produced large amounts of alcohol on their own when cultured in a dish. This seemed to be because they contained unusually high levels of certain gut bacteria, like Escherichia coli and Klebsiella pneumoniae, which naturally produce alcohol by fermenting sugars. Previous cases have been attributed to high levels of yeast colonising the gut. This also occurred in the , without consuming it.