A procedure that was touted as the future of medicine left a patient dead last summer, and now doctors are bringing transparency to the still-new technology.

Doctors, books and blogs have been publicizing fecal microbiota transplantation (FMT) — a procedure where stool from a donor is transplanted into the intestinal tract of a recipient in order to restore healthy bacteria to the gut — for years as a possible cure-all for a spate of illnesses including ulcers, leukemia and liver disease.

But in June, the FDA announced that two people who had fecal transplants from the same donor got sick with E. coli — and one of them died. But few details were shared about the scary incidents.

Now, doctors at Massachusetts General Hospital, where the incidents took place, want to give their side of the story, and hopefully dispel some of the fear hanging over current clinical trials of the procedure.

They published their rebuttal Wednesday in the New England Journal of Medicine.

“We wanted to set the record straight,” co-author Dr. Elizabeth Hohmann, an associate professor of medicine and infectious diseases at Massachusetts General Hospital and Harvard Medical School, told NBC News.

Clinical trials are ongoing. The procedure was originally developed — and has been successfully used — to treat the superbug Clostridium difficile (C. diff), a life-threatening, diarrhea-producing, antibiotic-resistant infection.

In the report, the doctors explain that both cases used contaminated stool by the same donor, even though they were in different clinical trials — one for liver disease and the other for leukemia. After developing E. coli, even with extensive treatment, the patient with leukemia could not be saved.

“This is a cautionary and sad tale,” Hohmann told NBC News. “It points out some of the important medical issues about immune-compromised [patients].”

The incidents were a lesson-learned situation, she continued.

“Maybe … changing the microbiome is not always a good idea,” she said of patients with compromised immune systems, such as those with cancer.

Even with the FDA’s new guidelines, which mandate both the poop and the donor be tested for “multidrug resistant organisms,” Hohmann warns that there are a lot of other organisms out there that aren’t being screened for.

“We can increase the ways we look for this,” she told NBC News. “But we can’t 100 percent eliminate it.”