What is Crohn's Disease?
Crohn's Disease falls under the broader category of conditions known as Inflammatory Bowel Disease (IBD)--as the name implies, it affects the "bowel", that is, the muscle-lined pipe that starts at our mouth and ends at our anus which we rely on to get ingested goodness to our muscles and organs.
Crohn's is a chronic condition, that is, something that once diagnosed we live with for the rest of our lives. Similar to Diabetes, there is no cure, only treatment. Generally speaking people who have Crohn's, or its close cousin, Ulcerative Colitis (UC) were diagnosed when they were in their early to mid-twenties. Crohn's sufferers experience a number of different types of symptoms, ranging from abdominal pain to diarrhoea to blood in the stool. The symptoms present predominantly in the intestine, but there are also so-called systemic symptoms that can present such as joint pain (arthritis).
Observations about Crohn's are that there seems to be a genetic component but that it's quite complicated and really only determines a predisposition to its development (that is, the fact that you have the Crohn's "gene" doesn't necessarily mean that you'll end up with the disease). Other things have been observed to correlate with high levels of reported Crohn's cases--for instance, if you live in the city, it would seem that you are more susceptible than a country-dweller.
What causes it?
When a Crohn's sufferer experiences a so-called "flare", the lining of their intestine becomes the mistaken target of attack by their very own immune system. In this regard, Crohn's appears to share a cause with other immune-system related chronic conditions such as some forms of asthma, and arthritis. I say "appears to" because despite our best efforts to understand the likes of Crohn's and UC, we still don't know what causes it.
Given the fact that Crohn's affects the bowel, the uninitiated could easily be forgiven for suggesting that diet might be the cause of the condition (or at least be a significant contributor). Interestingly, although diet has, at least to some degree, been shown to affect the intensity of the condition, there is no definitive link between what we eat and the cause of Crohn's.
If what we eat doesn't cause Crohn's, then how about whether or not it affects our chances of triggering it? Sadly, not much is known in this regard, but more and more, our modern lifestyles are coming under the spotlight (including the vastly different profile of foods that we consume compared to a hundred years ago).
Once diagnosed, a Crohn's sufferer is advised to avoid foods high in fiber and fat, especially if they are experiencing a flare. Advice by doctors to avoid these nutritional components is largely based on the tendency of fiber and fat to aggravate an already sensitive large or small intestine. Are there any foods or food types that we can associate with the intrinsic inflammatory action of Crohn's? Once again, we just don't know enough to be able to answer this question.
Modern thinking around nutrition is starting to point a finger at certain food types as being the unashamed culprits when it comes to inflammation in general. "Inflammation" is a term which is used in the medical world to refer to a normal immune response. If our bodies detect "baddies", an army of immune cells are sent flooding to the infected area, resulting in inflammation. So inflammation is actually a perfectly normal bodily reponse to infection---it's out-of-control or misdirected inflammation which is bad and is now commonly being associated with our modern lifestyle. High glycemic (or "fast burn") carbohydrates ingested continuously and over a long period of time are now generally considered to be the cause of abnormal inflammation. Could too much sugar in our diet, from a young age be the cause of a disease like Crohn's? It's beginning to look more and more like that could be the case.
Apart from dietary considerations, the other big difference in our lifestyles now as compared to years gone by is the amount of stress we endure. In respect of Crohn's, the correlation of city living with incidence of the disease could well be attributed to the inevitable increased stress levels associated with city living.
Stress is without a doubt a major contributor to the onset of Crohn's or UC flare-ups amongst sufferers. That said, there is no proof that a particularly intense bout of stress can cause Crohn's.
Management of stress is one of the major ways in which sufferers can avoid having to deal with flare-ups in the course of their lives.
The medical world has accepted that an active lifestyle will improve quality of life for a Crohn's sufferer. This isn't tremendously surprising though---compared to a typical couch-potato, someone who deliberately exercises on a regular basis is less likely to develop a whole gamut of modern diseases. Folk who have to deal with chronic illnesses also tend to be amongst those who have developed a level of discipline in regard to exercise because they've had the ironic "benefit" of a firm health kick-up-the-behind.
Exercise is known to lower stress levels so a natural follow-on from this is that exercising should lower susceptibility to stress-related illness, including a Crohn's flare-up.
Since researchers first started looking into candidate causes of Crohn's, the possibility that it could be triggered by a bacterium or virus has never been discounted.
The fact is, although we still don't know what causes Crohn's, there is now a strong indication that it is somehow related to the bacteria that necessarily form part of our digestive system. We have a symbiotic relationship with several hundred different strains of bacterium in our gut---they feed on food in our gut, breaking it down so that the inner lining of our intestine is able to absorb the resultant nutrients. When we are born, our bodies allow the intestinal bacterial profile to become established---a few weeks after birth, the bacteria that have established themselves in our intestine are seen as "friendly" and are therefore not attacked. The problem appears to come in as a result of the immune system of a Crohn's sufferer "losing the plot" in later years and mistakenly attacking friendly bacteria or intestinal tissue in the same locality.
In any case, studies around the possibility that a certain pathogen could be the cause of Crohn's continue. A recently popular theory is the possibility that the so-called Mycobacterium Avium subspecies Paratuberculosis (MAP) bacterium is the culprit.
How is Crohn's Treated?
Since the cause of Crohn's disease is not known, the only available means of treatment revolve around the symptoms. An out-of-control immune system needs to be brought into control or "quelled", so typically drugs that have a suppressing effect on the immune system are employed.
Most people who suffer from Crohn's are healthy most of the time, but every now and again experience a flare-up. Typically their specialist will prescribe drugs that suppress the immune system, effectively calming it down. The downside of this broad immune system suppression method is that, of course, a weaker immune system means that one is more prone to infection. As advanced as we may think we are when it comes to medicine, the means that we have to deal with something like Crohn's are relatively primitive. Never-the-less, for the most part, drug-based treatment is effective.
Recently, advanced medicines known as biologics have been employed to treat Crohn's with great effectiveness. A biologic is a drug that has been manufactured to be very specific in how it operates; to use an analogy, a biologic is a snipers rifle to the shotgun of traditional medicines. Unfortunately these drugs are made using a painstaking process and have a correspondingly high price-tag. Crohn's sufferers who need a biologic to manage their condition typically require their health insurance to foot a bill in the region of $18,000 per year.
Narrowing in on a Cause
Although technology marches on and correspondingly our ability to pinpoint causes of obscure medical conditions (all the well-known ones are understood now), the exact cause of Crohn's disease remains elusive.
There is a theory that the reason for the cause of Crohn's not having been identified is that it is as a result of a complicated "perfect storm" of a multitude of factors including diet, infection, genetics and lifestyle. Some more cynical commentators suggest that a reason for the cause not having been found is simply that there is no incentive to find it--a very short step beyond knowing a definitive cause is coming up with a cure. A cure would put a stop to a what is presently an exceedingly lucrative annuity-based revenue model centering on treatment of the disease with drugs.