Ideal Donors for Fecal Transplant Rare

Caroline Helwick

May 19, 2015

WASHINGTON, DC — It happened. An unanticipated large number of asymptomatic people failed stool screening at a large public bank. Only 8.5% of potential donors were ultimately accepted.

"It's clear that it's very difficult to become a stool donor," Laura Burns, from OpenBiome, said here at Digestive Disease Week 2015. "It's actually more difficult than getting into Harvard."

OpenBiome is a nonprofit bank, based in Medford, Massachusetts, that provides fecal microbiota to physicians around the world.

Fecal transplantation has emerged as a promising treatment for recurrent Clostridium difficile infection. To meet increasing demand, public stool banks have begun to supply fecal material from rigorously screened, universal, long-term donors. However, the best means of assessing stool donors and factors that should exclude donors have not been fully established, explained Burns, who presented results from a study conducted in conjunction with the Massachusetts Institute of Technology in Cambridge.

Many people failed stool screening because of the incidental detection of gastrointestinal pathogens, many of which are not included in standard screening panels, she explained.

Candidates for the group's Stool Donor Registry complete a 10-item prescreening survey designed to identify or rule out potential donors. Common reasons for exclusion at this stage are body mass index, recent antibiotic use, travel history, donation logistic difficulties, and lack of commitment (donors are expected to come in at least three times a week).

People not excluded by the prescreening survey are eligible for an onsite visit, during which they undergo a 109-question clinical assessment by a gastroenterologist and qualified research nurse. This is intended to rule out risk factors for transmissible diseases and potential microbiome-mediated conditions. Those who meet all criteria then undergo a comprehensive stool and serologic screening panel.

It's very difficult to become a stool donor. It's actually more difficult than getting into Harvard.

Burns reported data from 459 people in the registry. Of these, 208 were excluded by the prescreening survey.

Because of limited resources, the researchers invited only 77 of the 251 potential donors to the onsite visit for further evaluation. After clinical assessment, 50 people were excluded, mainly because of sexual history (10%), travel history (10%), or psychiatric concerns (18%).

The remaining 27 potential donors underwent blood and stool assessment, which eliminated 15 people because of stool, not blood, screening considerations.

Six people were excluded because of rotavirus, which was asymptomatic. None of these donors had healthcare exposure or contact with young children or daycare, Burns pointed out.

"We ultimately enrolled 12 donors, which was an 8.5% donor enrolment rate," she said.

Low Enrollment

As of May 15, the donor enrolment rate was just 4.0% of the registry of 6157 people. "We are just getting more and more selective," Burns told Medscape Medical News.

She said she would like to see an emphasis on the evaluation of the safety and efficacy of fecal transplantation, particularly over the long term, to better understand the role of the microbiome. Ultimately, the goal of such research would be the development of consensus-based guidelines for donor screening. Her group is currently conducting the STOOL study, which is a longitudinal evaluation of fecal transplantation in patients with recurrent C difficile.

"We want to know that, across this field, fecal material will be safe," Burns said.

Dawn Sears, MD, from Baylor Scott and White Clinic in Temple, Texas, said these findings give her more confidence in her center's decision to abandon directed donation in favor of obtaining fecal microbiota from OpenBiome.

"We are very pleased to see the rigorous collection of stool and serum of donors because we are using OpenBiome samples to treat and cure our patients with C difficile, and we are having a great experience with this," she said.

"When we were using family donors, we were finding the same thing — a large amount of norovirus. This was requiring us to repeat-screen second and third donors, and this creates expense," she pointed out. "Going to OpenBiome, we don't have to screen multiple people and we only have to pay once. We just pay $200, versus $500, times three to four, to find one good donor out of several. This is much more cost-effective."

Ms Burns is employed by OpenBiome. Dr Sears has disclosed no relevant financial relationships.

Digestive Disease Week (DDW) 2015. Abstract 499. Presented May 18, 2015.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.