The exact cause of Crohn's disease is unknown, however, researchers believe that a combination of genetic, environmental, immunological, and microbial factors contribute to the disease.
Genetics: Studies have shown that having a family member with Crohn's disease increases the risk of developing the disease by 20-25%. While a genetic factor is believed to be the main contributor to Crohn's, not all people with the disease have a family history of it.
Environmental Factors: Studies suggest that people living in industrialized countries are more likely to develop Crohn's disease. It is believed that environmental factors may contribute to the development of Crohn's by altering the immune system's response to certain bacteria in the gut.
Immune System: People with Crohn's disease have an abnormal response to bacteria in their intestines. The immune system in people with Crohn's disease overreacts, leading to inflammation and damage to the intestines.
Microbial Factors: Studies have shown that certain bacteria, such as Escherichia coli and certain types of Mycobacteria, are more common in people with Crohn's disease. It is believed that these bacteria may be involved in the inflammation and damage to the intestines.
In conclusion, the main cause of Crohn's disease is still unknown, however, a combination of genetic, environmental, immunological, and microbial factors are believed to contribute to the development of the disease.