Saturday, February 7, 2015

Woman becomes obese after fecal transplantation from overweight donor

A new case report published in the journal Open Forum Infectious Diseases reveals that a woman who was treated for a recurrent Clostridium difficile infection with the gut bacteria of an overweight donor quickly and unexpectedly gained weight herself following the procedure. The authors say the case suggests doctors should avoid using bacteria from overweight donors for such treatment.

Infection with C. difficile can cause inflammation of the colon, leading to diarrhea, fever, loss of appetite, abdominal pain and nausea.

According to the Centers for Disease and Prevention (CDC),
C. difficile is responsible for around 337,000 infections and
14,000 deaths in the US each year. Elderly individuals and
people with certain medical conditions are most at risk of C. difficile infection.

For primary C. difficile infection, antibiotics are the first port of call when it comes to treatment, and for most patients this is effective. Some patients, however, may experience recurrent C. difficile infection. In such cases, fecal microbiota
transplantation (FMT) may be recommended.

FMT is a procedure in which a stool is collected from a donor free of C. difficile, and "friendly" gut bacteria are
isolated from the fecal matter.

This bacteria are then transferred to the recipient's gut, with the aim of replacing
the good gut bacteria that may have been suppressed by
overpopulation of C. difficile.

The 32-year-old woman described in the case report underwent
FMT at Newport Hospital, RI, in 2011 after experiencing recurrent C. difficile infection.

According to the report authors, including Colleen R. Kelly of
the Warren Alpert Medical School at Brown University in Providence, RI, the woman weighed 136 pounds and had a
body mass index ( BMI) of 26 at the time of the procedure.

The donor bacteria used for transplantation came from the
woman's 16-year-old daughter, who was healthy but overweight - with a weight of 140 pounds, which later rose to 170 pounds, and a BMI of 26.4.

Woman experienced continued weight gain after FMT, despite diet and exercise
The report states that 16 months after undergoing FMT, the patient reported a weight gain of 34 pounds, taking her weight
to 170 pounds and her BMI to 33, which is classed as obese.

Despite undergoing an exercise program and a supervised liquid protein diet, the woman continued to gain weight; 3
years after the procedure, she weighed 177 pounds and had a BMI of 34.5. Today, the woman remains obese.

Prior to undergoing FMT, the woman tested positive for
Helicobacter pylori infection alongside C. difficile infection.

This was treated with amoxicillin, clarithromycin and proton pump inhibitor, and such treatment has been associated with gain, the authors note.

"However," they add, "it is notable that [the patient] was never obese prior to FMT, and that the stool donor similarly
experienced significant weight gain, raising the possibility that the obesity was at least in part a consequence of FMT." They
add that previous studies in animal models have shown it is
possible that obese microbiota can be transmitted.

As such, the authors say this case report indicates that doctors should avoid using obese patients as donors for FMT:
In an editorial linked to the study, Dr. Ana A. Weil and Dr.
Elizabeth L. Hohmann - both of the Massachusetts General
Hospital - say this case report emphasizes the importance of
investigating the long-term effects of FMT and raises a number of questions about the donor selection process for the

"FMT has not been studied in large-scale controlled trials, and we have much to learn about the effects of this treatment
beyond the intended restoration of a diverse microbiota," they

"Careful study of FMT will advance knowledge about safe
manipulation of the gut microbiota. Ultimately, of course, it is hoped that FMT studies will lead to identification of defined
mixtures of beneficial bacteria that can be cultured, manufactured and administered to improve human health."

In November 2014, Medical News Today reported on a study suggesting that people who have a class of bacteria in their gut
called Christensenellaceae - the presence of which is mainly
influenced by genes - are more likely to have a lower body