by Eric Hal Schwartz
Our digestive system is a zoo, filled with trillions of dangerous bacteria. Thanks to billions of years of evolution, however, we can not only keep the voracious creatures from hurting us, but actually turn them into essential participants in digestion. Crohn’s disease is one possible breakdown of this fragile arrangement into a chronic inflammatory bowel disease with painful and potentially fatal consequences if left untreated.
“It can be a disabling, degrading and devastating disease,” said Dr. Theo Heller, chief of the Translational Hepatology Unit at the National Institute of Diabetes and Digestive and Kidney Diseases at the National Institute of Health.
Crohn’s disease has complex links to genetics, the immune system and physical conditions still not completely understood despite ongoing medical advancements.
Although the inflammation is most common in the lower intestine, Crohn’s can cause problems anywhere along the digestive track. Some of the common symptoms, like stomach and gut pain, diarrhea, fever, rashes and joint pain are common enough that many people are not even aware of the source of their pain.
“Patients don’t even realize how sick they are,” Heller said.
Fatigue and irritability, often a result of needing the bathroom 20 times a day or more are also common to Crohn’s sufferers, especially before they receive treatment.
“It destroys the foundations of people’s lives,” Heller said.
The broad swath of possible Crohn’s symptoms makes a simple diagnosis difficult even as tests have improved.
“There’s no specific defining measurement for Crohn’s,” said Dr. Michael Zasloff, the director immunology at Georgetown University.
Although it has a genetic origin present from birth, most people do not begin to experience symptoms until young adulthood, Zasloff said. It’s then that the abdominal discomfort starts for most people with Crohn’s disease. The exact origins of Crohn’s disease are complex enough that the combination of genetic and environmental factors is still being uncovered but the basic expression of the disease at least is pretty well understood.
“It’s a defect in the way we sense and handle the microbiome [microscopic ecosystem],” Heller said.
That inability to control the bacteria and keep them where the body normally corrals them for use as digestive aids means the bacteria can spread to other areas where they are a dangerous infection. The infection and the body’s efforts to fight the bacteria give rise to the medical issues of Crohn’s disease.
“There’s failure to manage and contain the normal bacteria within the small intestine,” Zasloff said.
Naturally, the body responds to the unwanted presence of bacteria with the immune system, sending white blood cells to the area and inflaming the region in an effort to fight the strayed bacteria. Heller said Crohn’s is often confused with irritable bowel syndrome (IBS) but that while patients with Crohn’s may have IBS, it is not the same disease. If left untreated, the symptoms and pain can get worse and worse and can ultimately be fatal.
It’s thanks to advances in areas like genetics that Crohn’s is as explicable as it is today, Zasloff said. Since it was first named Crohn’s disease in the 1930s, baffled doctors have ascribed causes including childhood stress to the disease.
“Our understanding of Crohn’s has dramatically changed in the last 10 years,” Zasloff said.
Crohn’s is not very common, and just one in 544 people in the United States has it, according to the World Health Organization. Its genetic component means it runs in families, however, and in some populations, the incidence is much higher than the overall population.
“The highest percentage of people who have it are Ashkenazim,” Heller said.
Happily for those suffering from Crohn’s, it is possible to manage the disease with drug therapy like immunosuppressants and anti-inflammatory drugs to limit the inflammation caused by the bacteria. Depending on the kind and intensity of the symptoms, surgery to remove some of the colon or intestine helps patients control the symptoms. Although there are variations in each expression of the disease, Heller said that bland food can help limit abdominal stress in patients and that heart-healthy diets and keeping up good overall health can play an important role in helping patients.
The future for Crohn’s patients looks bright, both Heller and Zasloff agree. Between advances in understanding how the disease works, and personalized medicines to address the root of the problem and not just the symptoms, the next decade or so should see a marked improvement in how Crohn’s disease is treated. Future therapy may act as a way to replace the broken management system, artificially making up for the body’s inability to manage the zoo of bacteria.
“It will be a real revolution,” Heller said.