Man develops fatal bacterial infection after taking probiotics

An elderly man in Japan developed a fatal bacterial infection after taking a probiotic as part of his treatment for severe COVID-19.

The unnamed patient was initially brought to the emergency room after being discovered on the floor of his home. He had a history of colon cancer, chest pain, high blood pressure and pancreatic cysts. He was a heavy smoker and drinker at the time of his collapse.

ER doctors learned the man had COVID-19. They treated him with the corticosteroid dexamethasone and the immunosuppressive drug tocilizumab.

His breathing improved, but he had diarrhea from the medication. He was given a strain of the bacterium Clostridium butyricum, called C. butyricum MIYAIRI 588. Available in tablet form, CBM 588 is commonly used in Japan to treat diarrhea.

These tablets, prescribed to the man for one month, “have been widely used as probiotics for diarrhea in Japan and are also reported to improve symptoms of C. difficile [bacterial] infection and irritable bowel syndrome,” Fujita Health University Hospital researchers wrote last week in BMJ Case Reports.

CBM 588 capsules cannot be purchased in US stores, but can be purchased online. The drug is being tested in advanced kidney cancer patients at City of Hope Cancer Center in Duarte, California.

On his 33rd hospital day, the Japanese man was discharged from the ICU. About 25 days later, he started feeling constant pain in his stomach.

He rapidly developed multi-organ failure and died. It had been about two months since he was first hospitalized.

He had suffered from C. butyricum bacteremia, when the bacteria circulate in the blood, from taking the probiotic, and from non-occlusive mesenteric ischemia, or NOMI, characterized by decreased blood flow to the intestines.

“While probiotics are routinely prescribed [to] Ill patients with various gastrointestinal symptoms and conditions may experience rare but serious adverse events, as illustrated in this report,” the researchers wrote.

They called the man’s death “the first case of C. butyricum linked to probiotics [bacteremia ] after treatment of severe COVID-19.” Probiotics are supposed to help maintain a healthy balance of gut bacteria.

In a May study, researchers at Osaka University in Japan identified five cases of C. butyricum-causing bacteremia from probiotics.

“Probiotics can provide a variety of health benefits, but this study shows that even such agents can come with rare but serious side effects,” lead author Ryuichi Minoda Sada said at the time.

“Our findings highlight the risk for bacteremia resulting from the use of probiotics, particularly in hospitalized patients, calling for judicious prescribing practices,” Sada added.