Perianal fistulizing Crohn’s disease (PCD) is a complication of Crohn’s that affects up to 40% of Crohn’s patients. Fistulas form when abnormal connections form between the intestine and surrounding tissue.  Specifically, in the presence of inflammation, ulcers extend through the entire intestinal wall, creating a tunnel that drains pus away from the inflamed area. Fistulas may occur anywhere along the GI tract and are very painful and difficult to treat.

In good news for patients, a 2025 study published in The Journal of Clinical Investigation identifies new factors that contribute to fistulas. Examining samples of patients with PCD, researchers found that a specific immune signal--interferon gamma (IFN-γ)—was highly active in patients with PCD. This over-activation was linked to inflammation and changes in tissue that allow fistulas to form and persist.

The study also identified high numbers of a type of white blood cell, Th17 immune cells, which help protect the body from infections. In PCD, however, these cells produced large amounts of IFN-γ, fueling inflammation and tissue damage. Together with other immune cells, they created a cycle that drives fistula formation.  Combined, these new findings may pave the way for more effective treatments of fistulas and much needed relief for patients.

References

​Crohn’s & Colitis Foundation

Revealing hyperactivated IFN-γ pathways in perianal fistulizing Crohn’s disease using single-cell and spatial multi-omics, J Clin Invest. 2025; 135(17):e193413.

Service dogs are specially trained to help people with disabilities, including people with Crohn's disease.  Under the Americans with Disabilities Act (ADA) service dogs are allowed in public places like restaurants, schools, stores, and airplanes. Service dogs offer emotional support and can help with important tasks that are challenging during episodes of pain or fatigue.  Typical daily tasks that a service dog can be trained to help with  are:

• Carrying heavy items like backpacks or books
• Opening doors
• Switching lights on and off
• Fetching items such as a cellphone 
• Reminding to take a medication

Some patients report that their dogs also can recognize symptoms of a flare, sometimes before their owner does.  Another important benefit of service dogs is that they encourage their owners to be more active. Like all dogs, service dogs need exercise and playing with their owner outdoors is a great way to get it.

Determining whether a service animal is right for your child also requires careful consideration of whether your family is ready to take on the costs, new routines, veterinary care, and special training required to integrate a dog successfully into your home. 

To find out if a service dog might be right for your family, talk to your doctor and consult an accredited member of  Assistance Dogs International.

​Explaining inflammatory bowel disease (IBD) to a child is not easy. It's normal for kids to have lots of questions, but sometimes difficult for them to understand the way adults talk about the disease. To help kids learn more about what is going on, the Crohn's & Colitis Foundation (CCF) brought together a writer, artists, and medical professionals to create a comic book all about Crohn's and colitis, "Pete Learns All About Crohn's and Colitis." 

The colorful comic includes a glossary of commonly used medical terms, symptoms, and tests, and covers helpful topics such as what the intestines do, tips for taking medications, coping with embarrassing symptoms, and how to talk to friends about the disease.  Reading the comic together is a great way for parents and children to start a conversation about any concerns or questions they have about having IBD.  

A digital version of the comic is available for free on the CCF website.  

​A study published in the Gastroenterology journal by a Canadian research team documents that population and ratios of specific gut bacteria are uniquely different in those patients who develop Crohn’s disease as opposed to those who do not, and this gut bacteria differentiation can be identified years before Crohn’s Disease symptoms develop.
 
Dysbiosis involving five key bacteria contributed to subsequent Crohn’s Disease.  The five bacteria are:  “Ruminococcus torques, Blautia, Colidextribacter, an uncultured genus-level group from Oscillospiraceae, and Roseburia.”  (https://pubmed.ncbi.nlm.nih.gov/37263307/)
 
The discovery constitutes two important advances.  First, it provides clinicians with the ability to identify the bacteria populations that make one prone to development of Crohn’s Disease based upon identification of bacteria in one’s microbiome.  Second, with the specific bacteria now identified, clinicians can intervene in advance of symptoms to increase the population of good gut bacteria and decrease the population of the bacteria that instigate Crohn’s Disease.
 
One of the study’s authors, Dr. Kenneth Croitoru, told Crohn’s and Colitis Canada that “These years of effort led us to recently discover that a specific combination of gut bacteria is connected to the future development of Crohn’s disease. We’re starting to see the pattern of bacteria that may be triggering Crohn’s disease, moving us closer to better treatments for those with the disease or even preventing it for those at risk. I’m hopeful that within five years, patients will benefit through evidence-based treatments focused on the gut bacteria or diet modification.”   (https://crohnsandcolitis.ca/News-Events/News-Releases/Canadian-medical-research-breakthrough-Gut-bacteri).

​Traditionally it has been difficult for researches to study bacterial population changes in the small bowel, as they are only reachable during surgery or endoscopy.  Now, researchers led by Andrew Macpherson and Bahtiyar Yilmaz from the Department for Biomedical Research at the University of Bern and the University Clinic for Visceral Surgery and Medicine at the Inselspital have used patients with ileal ostomies as a means to survey the small bowel microbiome in real-time, leading to some interesting discoveries. 
 
Among the findings, ileal bacteria populations are highly variable, largely disappearing when individuals fast while sleeping overnight, only to bloom again when food is consumed at breakfast.  Interestingly, while the number of bacteria fluctuates significantly, the types of bacteria that comprise the microbiome do not.  The changes that occur in the bacterial populations also happen quickly, within hours of consuming a meal.  This differs from the bacteria in the large bowel, whose numbers and proportions remain stable.
 
The head of the study and its senior author, Andrew Macpherson, stated that "Because the system is so flexible, each bacterial species can adapt to a changing environment in the small intestine by changing the proportions of subspecies and thus prevent the species as a whole from dying out." As a result the ileal bacteria normally avoid species extinctions, unless there is an illness, malnutrition, or other environmental factor. 
 
These findings, and the use of small bowel ostomies as a research tool, will enable further research into the interaction of the small intestine microbiome and diseases like Crohn’s, Colitis, and celiac.  
 
(Plasticity of the Adult Human Small Intestinal Stoma Microbiota. Cell Host & Microbe, 2022; DOI: 10.1016/j.chom.2022.10.002).

​University of Gothenburg researchers have found a statistically significant risk of pre-term births to mothers who are Inflammatory Bowel Disease (IBD) patients.  IBD, including Crohn’s Disease and Colitis, causes visible inflammation and damage to the intestinal lining.  The new research indicates that even microscopic inflammation in a patient who might otherwise be considered to be in remission, has adverse implications for pre-term pregnancies.
 
Karl Mårild, the study's first author and corresponding author and an associate Professor of Pediatrics at Sahlgrenska Academy, University of Gothenburg, and senior consultant pediatrician at the Department of Pediatrics, Queen Silvia Children's Hospital, Gothenburg, stated:  "Our results suggest that IBD treatment aimed at not merely alleviate symptoms of IBD, but also microscopically heal the intestine, can reduce the risk of giving birth preterm. If our results hold up in future studies, they may therefore be the basis for recommendations to confirm microscopic healing before pregnancy, to reduce such risks."

Being in the hospital is no fun, but the day is a little brighter when someone shows they care with a thoughtful gift. Any thing that makes the stay more comfortable or help pass the time is welcome.  After spending many months in the hospital I'm somewhat of an expert patient, so I'm sharing here some of the great gifts people sent.

While I was in the hospital my parents spent hours playing with dolls, but not for fun.  The doll was basically my stunt double, allowing my parents to practice the complicated process of changing my parenteral nutrition infusion, setting the dosage correctly on the pump, and changing the dressings the PICC line insertion in my arm.  The expectation is that once I was discharged, my parents would take over from the nurses and be responsible for this daily process at home. Fortunately for all of us, I was able to start eating solid food again before I went home, but we'll never forget PICC baby.

For more information about PICC lines visit https://www.mayoclinic.org/tests-procedures/picc-line/about/pac-20468748

The hospital images most people remember from COVID show patients overcrowding hallways, chaotic ICUs, and exhausted staff.  For me, being admitted to a pediatric hospital at the very start of the shutdowns was a brief calm before the storm.  Bracing for the worst, non-emergency procedures were put on hold and hospital rooms emptied out.  Downtown streets were deserted, shops closed, and hospital corridors were eerily quiet.  Of course all that changed quickly and tragically, but I won't ever forget what it was like to inhabit this quiet, foreboding space, when any contact with another human was a calculated risk that could mean life or death.