Ulcerative Colitis, an Inflammatory Bowel Disease

Mitchell Auerbach, MD

Dr. Auerbach is a member of Westchester Digestive Disease Group whose special interests include ulcerative colitis and Crohn's disease. You can send questions about this article to Dr. Auerbach


ULCERATIVE COLITIS

The term “ colitis” is non-specific and refers to any inflammation of the colon. The colon, also known as the large bowel or the large intestine, is a hollow tube that connects the small intestine to the anus. The purpose of the colon is to reabsorb water and expel fecal wastes.

The gastroenterologist’s definition of diarrhea is a bowel movement that contains more than 8 oz. of water. This is otherwise known as bowel movements that are “ too loose or too frequent.” Under normal conditions, the nerves and muscles of the colon through coordinated action are able to regulate the forward propulsion of fecal wastes towards the rectum. The rectum then adapts by expanding to accommodate the bulky fecal matter and stores the material until defecation begins. The act of defecation is highly complex and involves the integrated action of the rectum, anal sphinctors, and the pelvic muscles all under the control of the nervous system. When a “colitis” is present, the inner lining of the bowel wall is inflamed and the colon cannot perform as it should. The transit of fecal wastes and the reabsorption of water does not occur properly and this manifests as diarrhea.
Sometimes the inflammation is limited to the rectal area. This is known as proctitis. When a colitis is present, the inflammation may only involve a short segment known as a “focal colitis” and thus symptoms may be mild; whereas, a “diffuse colitis or a pancolitis” may involve the entire colon and symptoms may be severe. As the inflammation becomes more severe, bleeding is likely to ensue. In addition, white blood cells arrive at the site to attempt to curb the inflammation. This is seen as pus exuding from the rectum. When the gastroenterologist looks into the colon with a colonoscope ( a thin, long rubber tube with a light and a camera built into the tip) to examine the tissue, the inflammation (colitis) becomes apparent immediately. When the colonic inflammation is just localized to the rectum, this is known as a “proctitis”.
As the primary purpose of the rectum is to adapt and store the fecal material, the effects of an inflamed rectum are profound. The tissue becomes hot and stiff. When a small amount of stool (feces) is presented to this region, it cannot be stored for future defecation because the adaptive compliance of the rectal muscle is lost. Instead, one experiences the immediate urge to defecate. Thus a “proctitis” leads to multiple, small, bowel movements. There is not much water in these movements because the remainder of the colon is functioning normally and is able to reabsorb water properly. When a “proctitis “ is severe, one may experience the urge to defecate, but be unable to defecate. This is known as “tenesmus” and reflects the sensation of “dry heaves” of the colon. Often an inflamed rectum will sense the presence of minimal stool and lead to immediate elimination. Another mainfestation of a hot, poorly compliant, inefficient muscle representative of a proctitis is “incomplete evacuation”. One may defecate and then feel the urge to return to the bathroom just minutes later. In addition, one may experience “incontinence” or “fecal soiling”; the inability to control the sensation to defecate. Commonly patients report that they awaken from sleep in the morning and their undergarments are stained with fecal material.
Bleeding can be mininal or severe. The bleeding that is associated with colitis or proctitis may be mild or severe depending on the extent of the inflammation. If the majority of the colon is involved, then one usually experiences loose watery bloody bowel movements. When only the rectum is involved, the patient may just experience the production of scant quantities of blood either in the toilet or on the undergarments.
The cause of ulcerative colitis is not known. Sometimes the term idiopathic ulcerative colitis is used. A condition is called idiopathic when medical science does not know the cause.
It is important to make sure there is not another cause of inflammation, such as infection.
So then, what is ulcerative colitis? It is a chronic inflammatory disorder of the rectum that often extends to involve the remainder of the large intestine in a continuous manner. The disease is characterized by exacerbations and periods of remission.
It is still unknown what causes this illness and what factors are responsible for an exacerbation. Therefore it is also known as idiopathic ulcerative colitis. Some patients may experience one flare of ulcerative colitis , respond to medical therapy, and remain in remission forever.
Thus, the diagnosis of ulcerative colitis is often very difficult to make and can be easily mistaken for another cause of colitis. Ulcerative colitis is a “clinico-pathologic” diagnosis; meaning it depends upon the patient’s proper complaints in addition to the proper colonoscopic (how it looks to the gastroenterologist during colonoscopy) and histologic (how biopsy specimens appear under the pathologist’s microscope) appearance. The diagnosis is also contingent upon the patient’s having negative stool cultures (meaning there is no infectious process). If the stool cultures do grow out an organism, then an infectious colitis would be the diagnosis, not ulcerative colitis. Often, a patient presenting with an infectious colitis will have the same presenting symptoms, as well as colonoscopic and histologic appearance. The implications for improperly diagnosing or failing to diagnose ulcerative colitis are profound as it is a chronic illness that requires long term daily medical treatment.
How come I have friends and relatives with “colitis” who have no problems and do not take any medications? “Colitis” is a loose term often used inappropriately by the lay public and sometimes by doctors as well. Often it is not meant to mean “ulcerative colitis” but instead it may mean one of the other many forms of colitis.
Infectious colitis is one of the forms of colitis that must be distinguished from ulcerative colitis. Infectious colitis is a colitis of sudden onset in which an identifiable source is often found on culture of the stool. Like the patient with ulcerative colitis a fever may be present, as well as abdominal cramping and pain. Even the colonoscopic appearance may be the same as the patient with ulcerative colitis but more likely it will be normal. However, under the microscope the tissue will usually be different from that of the patient with ulcerative colitis. The course of the patient with an infectious colitis is more favorable than the one of a patient with chronic ulcerative colitis because it will resolve quicker and chronic treatment is generally unnecessary.
Amebic colitis is caused by a parasite. The patient with amebic colitis is often mistakenly diagnosed as having chronic UC because the symptoms and the colonoscopic and histologic characteristics are exactly the same as the patient with UC. Also, the disease can manifest as a short lived or a chronic relapsing illness. However, amebic colitis is an infectious disease caused by the intestinal protozoan parasite Entamoeba histolytica. It is prevalent in the tropical regions of the world where water supplies are often contaminated. It is less commonly encountered in the US, but it is by no means rare. Transmission of the parasite is from person to person via the fecal-oral route or from contaminated water supplies.
Ischemic colitis is caused by insufficient blood supply to the colon. Ischemic colitis is an entity that usually affects persons over the age of 50 who have vascular disease (problems with the heart or blood vessels). The blood supply to the colon is compromised and the lining of the colon may bleed and slough off. Seldom are persons under the age of 40 affected except for an occasional person who engages in such vigorous exercise, such as marathon running, that blood is shunted away from the intestines for a prolonged period of time.
It typically presents suddenly with the onset of crampy pains and the immediate urge to defecate. The bleeding is severe and the first episode usually leads to hospitalization. Unlike UC, it usually improves by supportive care (intravenous fluids) alone. If colonoscopy is performed, unlike the findings seen in ulcerative colitis, only a focal region of inflammation is seen, usually in a portion of the left colon where the blood supply is naturally least abundant. The location of the inflammation in the colon is often the tipoff to this illness.
Pseudomembranous colitis: Sometimes the use of an antibiotic can lead to a specific type of colitis in a previously healthy individual. Pseudomembranous colitis is also known as clostridium difficile colitis (c. difficile) or antibiotic-induced colitis. This illness is caused by a bacteria called Clostridium difficile. Initial attempts to isolate and culture this bacteria were very difficult, hence its name.
In order to develop a diarrheal illness or a colitis from this bacterium, three things must happen:
  1. one must acquire the organism in the intestinal tract either from another infected individual or from the environment
  2. one must have disruption of the normal (usual) bacterial composition of the intestinal tract. Each of us under normal conditions has hundreds of species of bacteria in the colon. This is necessary such that certain foods can be broken down and digested. However, if one is either taking an antibiotic or receiving chemotherpy, then one is at risk of wiping out their usual bacteria. Then the clostridium difficile can take over and thrive in the colon.
  3. In addition to C. difficile becoming acquired in the colon and taking over the colon (through disruption by an antibiotic etc...), it must release a toxin into the colon that is capable of disrupting the colon’s daily activities (mainly water re-absorption) by producing diarrhea. In fact, the toxin often leads to a colitis with resultant bloody diarrhea.
Unlike UC, the colonic appearance of this bacterial infection is heralded by the production of a pseudomembrane, which looks like a yellow plaque stuck on the tissue of the colon. Treatment involves taking another different antibiotic that is capable of wiping out the C. difficile bacterium.
Crohn's colitis is another form of inflammatory disease that is related to, but distinct from, ulcerative colitis. Crohn’s colitis is an entity that describes a colitis in a patient with Crohn’s disease, which is an inflammatory disorder that can affect many different parts of the gastrotintestinal system. Crohn's colitis may be difficult to differentiate from ulcerative colitis. Both diseases together represent the entity of “chronic inflammatory bowel disease”. They have many similarities and the colonoscopic and microscopic findings often appear the same. The medications to treat both diseases are often the same as well. One subtle difference is that patient’s with colitis from Crohn’s disease often do not have involvement of the rectum, whereas the patient with UC nearly always has involvement of the rectum. Since the overall findings in these two chronic illnesses are so similar, 15% of the time an exact diagnosis cannot be made. Then the patient is labeled as having an “indeterminate colitis”.
Spastic colitis is another name for irritable bowel syndrome. Spastic colitis: This is a “loose term” to describe one variant of an irritable bowel syndrome. An irritable bowel syndrome, unlike the other types of colitis discussed before, may cause discomfort but not blood loss, infection, or life-threatening disease. Patients with an irritable bowel do not have any significant inflammation of the colon. Instead, they suffer from what is known as a functional disorder of the large bowel. They may experience excessive gas production, constipation, diarrhea, or lower abdominal crampy pain. These symptoms may be worsened by stress or poor dietary habits (eating low fiber, high fat, greasy foods). These persons generally lack weight loss, bloody bowel movements, and nocturnal bowel movements ( the need or urge to awaken in the middle of the night from sleep to move one’s bowels.) On colonoscopy, a patient with a “spastic colon” will not have any significant inflammation noted. However, on occasion, there may be a few patches of thick red folds representing “spasticity” of the bowel. This condition is best treated by a high fiber diet, a prudent diet, and stress reduction and exercise (i.e. aerobic activity).
Who is susceptible to ulcerative colitis? Ulcerative colitis usually affects young adults ages 20-40 but can occur at any age. Most believe that there is a second peak incidence that occurs at ages 55-65. It affects men and women equally. It occurs throughout the world but is more prevalent in the US, UK, Northern Europe and Australia. In the United States, Jews appear to be more affected than non-Jews. However, the disease has been reported in all ethnic groups. There does not appear to be any urban or rural differences in disease incidence.
Many theories about the cause of ulcerative colitis have been discredited. Ulcerative colitis was known to be a distinct entity as early as the late Ninteenth Century. At that time, reasearchers believed that the ulcerations found in an affected patient’s colon, as seen on autopsy studies, were due to an infectious process. However, no specific pathogen could be identified repeatedly and this theory lost credence. Then it was believed that food allergy was responsible for disease onset in select persons. Doctors found that patients who were placed on milk-free diets improved quickly. Then, when milk was re-introduced they became ill again. When further studies were performed, again, these theories have not held up. Years ago, many believed that it was psychiatric illness that led to disease onset. Patients were told that they had “a nervous stomach” responsible for their symptoms. However, no studies have verified these beliefs. It appears on occasion that one’s onset of disease may initiate after an extremely stressful life event. Thus, it is speculated that “ severe stress” may be one of many possible “triggers” that leads to disease onset. Still it is unknown what causes this chronic illness.
An abnormal immune response may cause ulcerative colitis. Smoking has been proposed as a factor contributing to the etiology of this illness. It has now been well accepted that ulcerative colitis is a disease of non-smokers although the direct mechanism is not understood. It is known that a non-smoker or an ex-smoker is at higher risk of acquiring this illness than a current smoker. In fact, this risk is highest in persons who have just recently quit smoking. This finding has led to reasearch involving the use of nicotine in the treatment of acute, active as well as chronic (remissive) ulcerative colitis.
It is now generally believed that there is an immunologic basis to the onset of disease activity. It is felt that certain individuals when exposed to a specific “trigger” develop an exaggerated immune response. This response is an inflammatory response that develops in the colon and is responsible for the underlying inflammation. In “normal conditions”, when the body recognizes a bacteria or virus or even a food product as “foreign”, multiple “inflammatory cells” (white blood cells ) are attracted to the scene and activate cell products which can “kill” or inactivate these “foreign substances”. In addition, in the “normal response”, the immune system is able to shut itself down, or turn off, when the attack is over. In a patient programmed to develop ulcerative colitis, the defect arises in that the immune response is too efficient, too exaggerated, and unable to be turned off. The entire response is over amplified and the release of inflammatory mediators, also known as cytokines, is massive. This is the basis for the abnormal “cellular response” that occurs in inflammatory bowel disease (both ulcerative colitis and Crohn’s disease). It is the inability to suppress ones own immune response that leads to the inflammatory condition. This is in complete opposition to the patient with the Human Immunodiefieciency Syndrome (HIV). An HIV infected patient is unable to mount the proper attack when exposed to foreign “triggers”. In addition to the abnormal “cellular” response in the patient with ulcerative colitis, there is an abnormal “humoral” response. This means that these patients inappropriately recognize their own cells and tissues as if they were a “foreign” substance. When one is infected with a virus or bacteria, the body usually makes a substance called an anitbody that is directly targeted to inactivate that specific invader. However, the patient with (UC) often recognizes his/her own tissues and cells as being “foreign” (like an invading bacteria), and produces antibodies against him/herself. This also leads to activation of numerous protective inflammatory components creating significant inflammation within the body. Thus, the goal of treatment is to suppress that rampant inflammatory response that develops in the affected patient. This is the rationale for the immunosuppressives and immunomodulatory agents (corticosteroids, Imuran®, 6-mercaptopurine, cyclosporine, methotrexate) being used to treat this illness.
Can I get ulcerative colitis if none of my relatives have the disease? It has been widely believed that there is a familial incidence of ulcerative colitis. Most studies have shown that 1-10% of persons with ulcerative colitis have a relative with the disease. The most impressive data comes from studies performed in Sweden. It is felt that first degree family relatives are more likely to be affected than other family members. A study performed in Copenhagen, Denmark reported a 10-fold increase in the risk of developing ulcerative colitis in first-degree relatives (parents, siblings, and children) of patients with this illness. Also, the risk appeared higher if the disease had been diagnosed in the patient before the age of 50.
In conclusion, it appears that there are many individuals who are genetically suceptible to acquire ulcerative colitis if exposed to the right environmental trigger. The exact trigger is unknown and has been postulated to include viral or bacterial infection, food allergy, nonsteroidal anti-inflammatory medications, smoking cessation, and oral contraceptives. Presumaby many genertically susceptible individuals are never exposed to the proper inciting factor and therefore, do not go on to develop the disease.
Treatment of ulcerative colitis includes both medicine and surgery. Ulcerative colitis is a very complex disease with many therapeutic approaches and alternatives available. There is not one standard medication nor one simple treatment. Overall, when a patient presents with sudden onset of active disease, the goal is to induce a remission, or a reveral of disease. Once remission has been achieved, the therapeutic objective becomes to sustain that remission for many, many years. In fact, some patients never experience a second flare of disease activity.
The initial therapeutic regimen varies with the extent of disease (meaning the amount and location of colonic tissue involved) and the activity of disease (meaning how severe is the inflammation.) As noted earlier, when the inflammation is limited to the rectum (proctitis), therapy with locally-acting medicated enemas and suppositories is often quite useful and all that is needed. If, on the other hand, inflammation is severe and involves most of the colon, then additional oral “systemic” therapy is warranted. The extent of disease is best assessed by the use of the colonoscope and interpretation of the colonoscopic appearance in conjunction with the pathologist’s report of the biopsied tissue. However, if the patient is quite ill having high fevers and multiple bloody bowel movements, then it may not be advisable or necessary to perform colonoscopy. The patient is classified as having moderate to severe disease and as is treated as such.
Very severe ulcerative colitis is called fulminant colitis. The classification of the severity or activity of the disease is based upon a modification of a classification scale proposed by many years ago by two British physicians, Drs. Truelove and Witts. They assessed the following factors:
  • The number of bowel movements over a 24 hour period with or without bleeding.
  • The presence of fever
  • The heart rate
  • Whether the patient is anemic (having a low red blood cell count)
  • The presence of an elevated sedimentation rate (a blood test that when elevated often indicates that there is marked inflammation somewhere in the body)
  • The presence of abnormal findings on physical exam
Mild disease would be characterized as
  • less than four bowel movements daily
  • the absence of rectal bleeding or abdominal cramping
  • and the lack of fever, elevated heart rate, anemia, or an elevated sedimentation rate
In contrast, severe disease would include
  • more than eight loose bowel movments daily, often with rectal bleeding
  • the presence of fever, weight loss, a heart rate greater than 100, an anemia (a low red blood cell count)
  • abdominal cramping, and “tenesmus”(rectal urgency)
Activity in between these two extremes is considered moderate disease. Those patients with severe disease who do not respond to therapy are labelled as having fulminant disease and often require emergent colectomy (the removal of the colon.) As ulcerative colitis involves only the colon, surgical removal of the colon results in a “cure “ of the disease. However, rarely is this drastic step necessary and most patients live a normal lifespan without ever undergoing surgery on the colon.

10/15/98

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