A 62-year-old woman developed serious intestinal problems similar to Crohn’s disease after receiving a stem cell transplant to treat cancer. Standard treatments didn’t work, so doctors tried a procedure called fecal microbiota transplantation (FMT)—essentially transferring healthy bacteria from a donor into her gut. After the procedure, her symptoms improved significantly, and tests showed her intestines were healing. Scientists found that harmful bacteria imbalances in her gut may have caused the intestinal damage. While this single case is promising, doctors emphasize that this treatment needs careful patient selection to avoid serious complications.

The Quick Take

  • What they studied: Whether transferring healthy gut bacteria from a donor could help a patient whose intestines were damaged after receiving a stem cell transplant for cancer treatment
  • Who participated: One 62-year-old woman who received a stem cell transplant from her daughter to treat a type of blood cancer (double-hit lymphoma) that had returned after other cancer treatment
  • Key finding: After receiving healthy gut bacteria from her daughter, the patient’s severe diarrhea improved, her intestinal ulcers healed, and she could return to eating normally without symptoms returning
  • What it means for you: This case suggests that gut bacteria imbalances may play a role in intestinal damage after stem cell transplants, and replacing those bacteria might help—but this is based on one patient, so more research is needed before this becomes standard treatment

The Research Details

This is a case report, which means doctors documented what happened with one specific patient in detail. The patient received a stem cell transplant from her daughter to treat cancer. Eight months later, she developed severe intestinal problems with diarrhea and ulcers that looked like Crohn’s disease (an inflammatory bowel condition). When normal treatments didn’t work, doctors performed a procedure called fecal microbiota transplantation (FMT), where they transferred healthy bacteria from the patient’s daughter’s stool into the patient’s intestines. Doctors then used genetic testing (16S rRNA analysis) to examine which bacteria were present before and after the procedure.

Case reports are important for identifying new treatment possibilities and understanding how diseases develop in individual patients. This case is particularly valuable because it suggests that the imbalance of gut bacteria after stem cell transplants might be causing intestinal damage, which is a new insight. By documenting exactly what happened and what changed, doctors can identify patterns that might help other patients facing similar problems.

This is a single case report, which is the lowest level of scientific evidence. It shows what happened to one person but cannot prove that FMT will work for everyone with similar problems. The patient did improve, and genetic testing confirmed changes in her bacteria, which strengthens the findings. However, because it’s just one patient, we cannot be certain the bacteria transfer caused the improvement or that it would work for other patients. More research with larger groups of patients is needed to confirm these results.

What the Results Show

The patient’s most severe symptom—chronic diarrhea—gradually improved after receiving the fecal microbiota transplant. Four months after the procedure, doctors examined her intestines with a camera and found that the ulcers (open sores) had healed and scarring had begun, indicating tissue repair. The patient was able to return to eating a normal diet without restrictions, and importantly, her symptoms did not return during the follow-up period. Her original cancer also remained in remission, meaning the transplant didn’t interfere with her cancer treatment.

Genetic analysis of her gut bacteria revealed an important change: the amount of a harmful bacteria called Enterococcus decreased significantly after the fecal microbiota transplant. This finding suggests that the imbalance of bacteria in her gut—called dysbiosis—may have been a key factor in developing the intestinal damage in the first place. By restoring a healthier balance of bacteria, the transplant may have allowed her intestines to heal.

The patient did not experience acute graft-versus-host disease (a serious complication where transplanted cells attack the patient’s body) after her initial stem cell transplant, which was a positive sign. The timing of her intestinal problems—eight months after the stem cell transplant and following a viral infection (cytomegalovirus enteritis)—suggests that the combination of a weakened immune system and bacterial imbalance may have triggered the intestinal damage. The fact that conventional treatments (standard medications for inflammatory bowel disease) didn’t help before the FMT suggests this was a unique problem requiring a different approach.

Doctors have previously reported cases of inflammatory bowel disease developing after stem cell transplants, but this case adds new information by showing that gut bacteria imbalance may be involved. Most previous cases were treated with standard medications, which often don’t work well. This case is one of the first to successfully use fecal microbiota transplantation for this specific problem, suggesting a new treatment direction. However, because this is just one patient, it’s too early to say whether FMT should become standard treatment for all patients with this complication.

This study has several important limitations: it involves only one patient, so we cannot know if results would be similar for others; we cannot be completely certain that the FMT caused the improvement, as other factors may have contributed; the follow-up period was relatively short (4 months after FMT), so we don’t know if benefits will last long-term; and the patient received the transplant from a family member, which may not be possible for all patients. Additionally, the doctors note that FMT carries risks, including serious infections like sepsis, so careful selection of patients is essential.

The Bottom Line

Based on this single case, fecal microbiota transplantation may be worth considering for patients who develop Crohn’s disease-like intestinal problems after stem cell transplants and don’t respond to standard treatments. However, this should only be done under careful medical supervision by experienced doctors, as the procedure carries risks. Confidence level: Low (based on one case). Patients should discuss this option with their transplant team and understand both potential benefits and risks before proceeding.

This finding is most relevant to: patients who have received stem cell transplants and develop unexplained intestinal problems; doctors treating stem cell transplant patients; and researchers studying complications after stem cell transplants. It may be less relevant to people with typical Crohn’s disease who haven’t had stem cell transplants, as their condition develops differently. Anyone considering this treatment should have experienced doctors evaluate whether it’s appropriate for their specific situation.

In this patient, improvements began gradually over weeks to months after the procedure, with significant healing visible on examination at 4 months. However, timelines may vary for different patients. It’s important to have realistic expectations: this is not a quick fix, and benefits may take time to appear. Long-term follow-up is essential to ensure benefits persist.

Want to Apply This Research?

  • If considering or undergoing FMT for post-transplant intestinal problems, track daily bowel movement frequency and consistency (using the Bristol Stool Scale: 1-7 rating), abdominal pain levels (0-10 scale), and dietary tolerance (which foods cause symptoms). Record these daily in a symptom diary to show your doctor objective changes over time.
  • Work with your medical team to gradually expand your diet as symptoms improve, starting with easily digestible foods and slowly adding variety. Use the app to log which foods are well-tolerated versus which trigger symptoms, helping identify your personal triggers. This information helps your doctor assess whether the treatment is working and guides dietary adjustments.
  • Establish a long-term tracking system that monitors: weekly symptom severity scores, monthly dietary diversity (number of different foods tolerated), quarterly weight and nutrition status, and ongoing medication needs. Share this data regularly with your transplant team to catch any early signs of symptom return and adjust treatment as needed.

This case report describes what happened with one patient and should not be considered proof that fecal microbiota transplantation will work for everyone with similar problems. If you have had a stem cell transplant and are experiencing intestinal problems, consult with your transplant team or gastroenterologist before considering any new treatment. FMT carries risks including serious infections and should only be performed by experienced medical professionals in appropriate clinical settings. This information is educational and not a substitute for professional medical advice, diagnosis, or treatment.