IBS – Cause, Symptoms & Management
IBS – Cause, Symptoms & Management
Irritable Bowel Syndrome or IBS, is a functional disorder of the gastrointestinal tract characterized by chronic abdominal pain and major alterations in bowel habits with no discernable organic cause. It was first described in 1892 by a Canadian physician, William Osler, who called it mucous colitis. It is also called spastic colon, nervous colon, irritable colon, and irritated bowel.
Irritable bowel syndrome is one disease that many people have but few talk about. An estimated 15% of the population have it and have been treated for it. However, the incidence is difficult to establish because of misdiagnosis by the health care professional and underreporting by the patient himself.
The causes of irritable bowel syndrome remain poorly understood but are currently under avid research. Postulated causes are: those related to enteric infection, those with central neurohormonal mechanisms and those related to dietary intake.
The disorder often manifests after a bout of gastroenteritis or stomach flu. This may be due to the persistence of colonic muscle hyperreactivity, and alterations in neural and immunologic processes of the small and large bowels. Infection with Giardia lamblia has been shown to lead to an increased prevalence of irritable bowel syndrome and chronic fatigue syndrome.
The limbic system of our brain mediates emotional and autonomic response. It has been shown to enhance bowel motility and reduce gastric motility in patients with IBS. Limbic system abnormalities have been described in patients suffering from irritable bowel syndrome and major depression. The hypothalamic-pituitary axis may also be closely involved. Disturbances in motility correspond to increase in hypothalamic release of corticotrophin-releasing factor in response to stress.
An intolerance to dietary fats may lead to bloating and distention. Also, short-chain carbohydrates such as fructose may also lead to irritable bowel symptoms.
The symptoms of irritable bowel syndrome are incredibly varied and may range from the very mild to the extreme. They are commonly directly associated with the digestive system and may include abdominal pain, abdominal distention, diarrhea, constipation, a combination of diarrhea and constipation, an increase in the frequency of stools, an urgency to pass stool, a feeling that you have not completely emptied the bowels after passing out stool, clear or whitish mucorrhea or mucus discharge with stools (sticky substance passed out with stool), nausea and vomiting, heartburn, and dyspepsia.
There may be presence of symptoms that do not directly concern the digestive tract. These may include sexual dysfunction, dyspareunia or pain during sexual intercourse, loss of libido, urinary frequency and urgency, fibromyalgia, headache, tiredness and chronic fatigue, backache, depression and anxiety.
Diagnosis is usually done by a careful history and by excluding other gastrointestinal diseases that have similar symptoms. An attempt to form suitable criteria to diagnose irritable bowel syndrome by symptoms was done to minimize the need for many tests to exclude other conditions. This set of criteria is the Rome III criteria for diagnosing Functional Gastrointestinal Disorders (FGID). Rome III says that one must have abdominal pain or discomfort for a minimum of three days per month over a period of three months and that this should be accompanied by any two of the following: abdominal pain is relieved by defecation, onset of the pain is accompanied by change in frequency of passing stools, and onset of pain is accompanied by a change in the appearance of stool.
There are four subtypes of IBS according to the Rome III criteria:
IBS-C is IBS with constipation, if more than 25% of stools are hard and lumpy and less than 25% of stools are loose and watery.
IBS-D is IBS with diarrhea, if more than 25% of stools are loose and watery and less than 25% of stools are hard and lumpy.
IBS-M is IBS mixed, if more than 25% of stools are hard and lumpy and more than 25% of stools are loose and watery.
IBS-U is IBS unsubtyped.
The stools are classified according to the Bristol Stool Form Scale.
There are a vast number of differential diagnoses for irritable bowel syndrome. These include colitis, Crohn’s disease, parasitic infection, celiac disease, food intolerance, depression, and colon cancer. These differential diagnoses are important and must be ruled out before a diagnosis of irritable bowel syndrome is made.
The following symptoms should alert the physician to a possible serious cause of the IBS-like symptoms: onset during middle age or in older individuals, acute onset of symptoms, progressiveness or worsening of the symptoms, symptoms occurring at night, anorexia or loss of appetite, weight loss, febrile episodes, rectal bleeding, painless diarrhea, steatorrhea or passage of fat with stools, and intolerance to milk, dairy products and gluten (a protein in wheat).
While there really is no definitive cure because the cause is yet unknown, irritable bowel syndrome can be successfully managed according to its predominant symptoms. Changes in diet and lifestyle, pharmaceutical drugs, and behavior therapy can be employed to manage the symptoms of irritable bowel syndrome.
Increasing the amount of insoluble fiber in the diet used to be one of the management options. It is believed to add bulk to the stool and enable the gut to function more routinely. This has however been noted to be untrue. While it is effective in persons without irritable bowel syndrome, the same cannot be said for IBS sufferers and may even cause the symptoms to worsen. Specialized diets and recipes have been formulated for patients with IBS and these may be worth trying.
Antispasmodics, laxatives, enhancers of gastric and colonic motility and tricyclic antidepressants are some of the pharmaceuticals used to treat the disorder. The side-effects of these drugs may not be very optimal for the patient though, and may even cause the symptoms of irritable bowel syndrome to worsen. As such, the benefits of use of these drugs should be carefully weighed against its adverse effects. In addition, they may even mask the symptoms of a serious gastrointestinal disorder such as colon cancer.
Recently, research has been done into the role of probiotic bacteria. This area of research looks promising for patients whose lives have been disrupted by irritable bowel syndrome.
Other avenues of treatment that are worth noting are hypnosis, mindfulness and cognitive behavior therapy (CBT). Given that IBS is a brain-gut dysfunction, hypnosis and behavior therapy must be considered a valid form of treatment. Hypnosis used alone has an 80% success rate, it has near-zero adverse effects, it is entirely comfortable, and it may even result in the improvement of other symptoms such as headache and fatigue. CBT, is also an effective treatment for IBS. It involves specific strategies for relaxation, coping with stress and facing difficult situations. Mindfulness has also proven to be very effective in helping sufferers of IBS. When these three modalities are integrated, the results can be quite remarkable.