Probiotics Don’t Keep Bad Bugs at Bay

Probiotics don’t protect the intestines of critically ill patients against antibiotic resistant bacteria, a new study indicates.

“With fewer therapies available to treat multidrug-resistant organisms, innovative methods to prevent or eliminate gastrointestinal colonization [by bacteria] are necessary,” said lead author Dr. Jennie Kwon, a clinical researcher in infectious disease at Washington University School of Medicine in St. Louis.

Colonization is the first step before a full-blown infection can develop, the study authors explained.

The current research included 70 patients in intensive care units who received either standard care or probiotics twice a day for up to two weeks.

Probiotics are live microorganisms - popularly called “good” bacteria. Probiotics are believed to boost a person’s resistance to harmful germs, the researchers said.

Antibiotic-resistant bacteria colonized the intestines of 10% of patients who received probiotics and 15% of those who got standard care. However, this difference was not statistically significant, the researchers noted.

The study was published August 27 in the journal Infection Control & Hospital Epidemiology.



Drug-resistant bacteria pose a serious threat to hospital patients because they increase the risk of hard-to-treat infections that spread easily, the researchers said.

Kwon said that further study should be done to see if other groups of people, such as those who are less ill, might be helped with probiotics.

My Take:
This is an area of great interest but a poorly designed study. Although the probiotic group had a reduced incidence of colonization of 5% (a one-third reduction), the study size was too small to be statistically significant. By comparison, statin drugs only reduce the risk of sudden heart attack from 3% to 2% - again, a one-third reduction.

However, the greatest issue is the use of just one probiotic - Lactobacillus rhamnosis GC. There is no “one size fits all” in probiotics. Your probiotic makeup is unique and the probiotic that is beneficial for you might be harmful to someone else. Family members that are genetically related and have lived together for many years have similar probiotic composition but even that has limitations.

Finally, using a critically ill population for testing is limited by the disease processes they are fighting. The microbiome (bacterial composition of the bowel) is diminished early in the disease process, regardless of cause and has a limited ability to respond.

The Bottom Line:
Probiotic use must be specific, both in composition and duration. Your immune system will respond to any probiotic, even if the bacteria are dead (most probiotic products do not contain viable bacteria). That immune response can be positive or negative. If you take a probiotic, take a specific culture for a limited period of time, recommended by a qualified physician for specific reason.

Source: September 2, 2015 National Institutes of Health