Man Becomes Drunk Without Consuming Any Alcohol Due To Gut Bacteria

An interesting case of a Chinese man reportedly becoming intoxicated without having touched a drop of alcohol has given researchers insight to a strange possible cause of nonalcoholic fatty liver disease. The remarkable man’s troubles began in college during which he became extremely drunk one night in 2004. For many this would hardly have been a notable event, except for the fact that the man hadn’t consumed any alcohol that night — only fruit juice. The bizarre incident soon turned into a pattern in which he would become severely intoxicated about once a month without having drank any alcohol.

By June of 2014, his condition had not gotten any better and he was admitted to the intensive-care unit of Chinese PLA General Hospital in Beijing. It was there that the doctors discovered that every time the man ate a meal that was high in sugar, his blood alcohol levels skyrocketed. In fact, his BAC was as high as it would be if he had taken 15 shots of 80-proof alcohol.

The man was diagnosed with a rare condition known as auto-brewery syndrome – a disorder that causes afflicted individuals to become intoxicated without drinking any alcohol. This happens when the microbes that are naturally found in a person’s gut ferment carbohydrates into excessive amounts of alcohol. Previously, auto-brewery syndrome was thought to be a product of an excessive amount of yeast in the stomach. However, rather than finding a buildup of yeast, the team of doctors treating the man discovered several strains of bacteria within his stomach known as Klebsiella pneumonia.

We were surprised that bacteria can produce so much alcohol. When the body is overloaded and can’t break down the alcohol produced by these bacteria, you can develop fatty liver disease even if you don’t drink.

- Dr. Jing Yuan at Capital Institute of Pediatrics

Klebsiella pneumonia is a common type of commensal gut bacteria. Although it’s generally harmless, it can cause severe infections if not closely monitored. Despite the fact that Klebsiella is not widely known for intoxicating people, lead doctor on the case Jing Yaun found that the patient had two particular strains of the bacteria that can produce alcohol. In fact, the Klebsiella had developed so forcefully that it made up 19% of the microbes of the afflicted man’s gut, becoming 900 times more common than that found in a healthy person. Doctors believe the bacteria was converting his food into alcohol, raising his blood-alcohol levels and damaging his liver.

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The Connection Between The K. Pneumonia Bacteria And Nonalcoholic Fatty Liver Disease

Intrigued, doctors at the Capital Institute of Pediatrics then studied patients with nonalcoholic fatty liver disease (NAFLD) to see if Klebsiella could be a factor in that condition as well. With NAFLD, individuals build up fatty deposits on their liver in the same way that heavy drinkers do, despite having touched little to no alcohol. Researchers analyzed 43 Chinese people with NAFLD and found that 61% had the same high-alcohol strains of Klebsiella pneumoniae bacteria as the man with auto-brewery syndrome compared to just 6% of healthy people.

To further test their hypothesis, the team fed strains of the bacteria to mice that had been raised in sterile conditions and lacked microbes of their own. Within two months, the rodents had signs of liver disease, inflammation, and scarring, comparable to that of mice that had been drinking alcohol itself. These results demonstrate that the bacterial strains could be an important cause of NAFLD. Additionally, it was found that when the team treated the mice with a Klebsiella-killing antibiotic, the condition reversed. Such findings suggest that doctors could potentially use viruses to target the Klebsiella pneumoniae bacteria to help treat NAFLD.

Despite her study outcomes, Dr. Yaun notes that NAFLD is a complex and varied condition, and that Klebsiella is just one possible cause of many. Yaun hopes that her research will motivate other studies to uncover why some people have high alcohol-producing Klebsiella while others do not. According to Yaun, “we don’t understand what factors would make someone more susceptible to these particular K. pneumonia, and that’s what we want to find out next.”

In terms of the auto-brewery syndrome afflicted man that inspired the NAFLD study, he was treated with an antibiotic and put on a no-sugar, no-carbohydrate diet for a total of three weeks. His intoxication symptoms slowly diminished, and he was released from the hospital two months later.

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Jena Hilliard

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  • Jena Hilliard earned her Bachelor’s of Arts degree from the University of Central Florida in English Literature. She has always had a passion for literature and the written word. Upon graduation, Jena found her purpose in educating the public on addiction and helping those that struggle with substance dependency find the best treatment options available.

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