The "report on xifaxan" is old now just fyi.
There was and still is some controversy over SIBO as a cause for IBS. Now they have fond some people have both IBS and SIBO. Basically Pimental jumped the gun by saying IBS is caused by SIBO. In that article I am friends with Dr Drossman and he has helped me for over ten years now, as well as many others at the UNC center for functional gi and motility disorders. I will still post more about that soon.
SIBO effects the small bowel. IBS is basically a problem with the large intestines.
In SIBO there can be malabsorbtion.
IN IBS there is no malabsorbtion.
Sibo can be cause by motility issues and be chronic.
IBS has motility issues, but motility alone does not explain the symptoms of IBS. In IBS its motility, Visceral hypersensitivity and brain gut axis dysregulation.
There are a lot of Educational Materials here.
http://www.med.unc.edu/medicine/fgidc/public_education_materials.htm
"Gut Bacteria and Irritable Bowel Syndrome
By: Eamonn, M. M. Quigley M.D., Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland
Bacteria are present in the normal gut (intestines) and in large numbers the lower parts of the intestine. These "normal" bacteria have important functions in life. A variety of factors may disturb the mutually beneficial relationship between the flora and its host, and disease may result. The possibility that gut bacteria could have a role in irritable bowel syndrome (IBS) may surprise some; there is indeed, now quite substantial evidence to support the idea that disturbances in the bacteria that populate the intestine may have a role in at least some patients with IBS. This article presents a discussion of the possible role of bacteria in IBS and various treatment approaches."
Do bacteria play a role in IBS?
The possibility that gut bacteria could have a role Irritable Bowel Syndrome (IBS) may surprize some; there is indeed, now quite substantial evidence to support the idea that distrubances in the bacteria that populate the intestines may have a role in at least some patients with IBS. What is this evidence? It can be summarized as follows:
1. surveys which found that antibiotic use, well known to distrub flora, may predispose individuals to IBS.
2. The observation that some individuals may develop IBS suddenly, and for the first time, following an episode of stomach or intestinal infection (gatroenteritis) caused by a bacterial infection.
3. recent evidence that a very low level of inflammation may be present in the bowel wall of some IBS patients, a degree of inflammation that could well have resulted from abnormal interactions with bacteria in the gut.
4. The Suggestion that IBS maybe Associated with the abnormal presents, , in the small intestines, of types and numbers; a condition termed small bacterial overgrowth (SIBO)>
5. Accumaliting evidence to indicate that altering the bacteria in the gut, by antibiotics or probiotics, may improve symptoms in IBS.
For some time, various studies have suggested the presence of changes in the kind of colonic flora in IBS patients. The most consistent finding is a relative decrease in the population of one species of 'good' bacteria, bifidobacteria.
However, the methods employed in these studies have been subject to question and other studies have not always reproduced these finding. Nevertheless, these changes in the flora, maybe primary or secondary, could lead to the increase of bacterial species that produce more gas and other products of their metabolism. These could CONTRIBUTE to symptoms such as gas, bloating and diarrhea."
"We still don't know the exact role bacteria has in IBS. More research is needed."
http://www.aboutibs.org/Publications/currentParticipate.html
However, there are other important issues in IBS in regards to cells in the gut that communicate back and forth with the brain that are also involved in IBS, ec cells and mast cells are two of them.
Harold J. DeMonaco, M.S.
Harold J. DeMonaco, M.S., is senior analyst, Innovative Diagnostics and Therapeutics, and the chair of the Human Research Committee at the Massachusetts General Hospital. He is author of over 20 publications in the pharmacy and medical literature and routinely reviews manuscript submissions for eight medical journals.
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June 19, 2001
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Irritable bowel syndrome is now recognized as a disorder of serotonin activity. Serotonin is a neurotransmitter in the brain that regulates sleep, mood (depression, anxiety), aggression, appetite, temperature, sexual behavior and pain sensation. Serotonin also acts as a neurotransmitter in the gastrointestinal tract.
Excessive serotonin activity in the gastrointestinal system (enteric nervous system) is thought to cause the diarrhea of irritable-bowel syndrome. The enteric nervous system detects bowel distension (expansion) on the basis of pressure-sensitive cells in the bowel lumen (opening). Once activated, these pressure-sensitive cells promote the release of serotonin, which in turn promotes both secretory function and peristaltic function (the contractions of the intestines that force the contents outward). At least four serotonergic receptors have been identified to be participants in the secretory and peristaltic response.
Patients with diarrhea-predominant IBS may have higher levels of serotonin after eating than do people without the disorder. This recognition led to the development of the first drug used specifically to treat diarrheal symptoms of IBS, alosetron (also known as Lotronex). Alosetron blocked the specific serotonin receptors responsible for recognizing bowel distention. In doing so, it blocked the effects of serotonin and reduced both bowel secretions and peristalsis. Constipation was the most common side effect seen. (Note: Alosetron was removed from the market by the manufacturer after repeated reports of a dangerous condition known as ischemic colitis became known.) Tegaserod (Zelmac) is another drug under development and under review by the U.S. Food and Drug Administration for approval. Tegaserod is indicated for the treatment of constipation-predominant IBS and works to increase enteric nervous system serotonin activity.
So, increasing serotonin activity in the enteric nervous system produces increased bowel secretions and peristalsis (and potentially diarrhea), whereas depressing serotonin activity produces reduced secretions and reduce peristalsis (and potentially constipation). Increasing serotonin activity in the brain would increase awareness and, in higher doses, produce anxiety, insomnia and restlessness."
also
'Functional syndromes' • Brains interpret pain signals differently
By Tina Hesman Saey
ST. LOUIS POST-DISPATCH
07/08/2007
All Tina Allen wants is a doctor like TV's Dr. House. He'd figure out what's wrong with her.
She has plenty of symptoms and diagnoses. Her medical records cram a tote bag 6 inches thick. She's boiled down the highlights for new doctors into a four-page summary. It starts with a list of 29 symptoms and 26 diagnoses and ends with a plea for a House-like commitment to get to the bottom of what's wrong.
Allen has a suite of conditions that includes irritable bowel syndrome, fibromyalgia, headaches and pain and tingling in her hands and arms.
Millions of people across the country share at least one of Allen's conditions, and many battle more than one. Advertisement
Doctors have been stumped as to why those people are so susceptible.
But researchers, including some in St. Louis, now think the ailments may have a common cause. Studies have shown that the brains of people with these conditions may interpret pain signals differently than those of other people.
Doctors have labeled the problems "functional syndromes" because they haven't found a physical cause for the complaints.
In fact, most patients with combinations of these conditions have been told at least once that the problem is all in their heads.
"The way that society and the health care system responds to these disturbances is part of the problem," said Dr. Emeran Mayer, director of neurovisceral sciences and women's health at the University of California at Los Angeles.
Separating symptoms
Most of the time patients are referred to specialists and subspecialists to deal with individual sets of symptoms. Patients tend to talk about digestive problems only with their gastroenterologists, saving joint pain and headaches and other problems for other specialists, Mayer said.
But patients will report those other problems if asked.
about eight years ago, Dr. Ray Clouse, a gastroenterologist at Washington University, and his colleagues started asking patients to fill out a form listing about 30 symptoms, only a subset of which included stomach and bowel problems. Patients who had conditions such as Crohn's disease or ulcers usually would mark only stomach pain and bleeding. But patients with irritable bowel syndrome and related conditions often would tick off nearly all the digestive tract symptoms plus a host of others including trouble sleeping, joint and muscle pain, lower back pain and headaches, Clouse said.
As many as one in five people have irritable bowel syndrome. Between 3 million and 6 million people, most of them women, suffer from fibromyalgia. People with fibromyalgia experience joint and muscle pain, fatigue and multiple tender spots. The tingling and pain in Allen's hands, a condition known as peripheral neuropathy, affects about 20 million people. about half of patients with one of the ailments also have others, such as chronic fatigue syndrome, tension headaches, restless leg syndrome or multiple chemical sensitivity.
The doctors weren't the first to note that patients with functional syndromes often have a history of psychiatric conditions such as depression or anxiety.
"That was a big distraction," Clouse said.
The correlation pushed doctors into two camps: those who believed the syndromes were psychiatric conditions and those who thought they had physical causes. The fact that low doses of antidepressants or talk therapy are often effective in treating irritable bowel syndrome and other functional disorders further complicates the matter, Clouse said.
Geared-up processing
Brain imaging studies show that the nerves of people with functional syndromes send normal pain signals to the brain. Once those signals reach the brain, though, they are processed in areas involved in emotion, stress and thinking. That processing center appears to be more active in people with functional disorders, suggesting that the interpretation of pain signals, rather than the sensation itself, goes awry in people with the syndromes, Clouse said.
What's more, the geared-up processing center may rile up the autonomic nervous system — the part of the nervous system that controls automatic responses such as sweating, heartbeat and blood pressure — so it makes the person sweat, causes cramps and triggers pain. Those sensations are sent back to the brain where the whole process repeats, each time rachetting up the patient's pain and distress, Clouse said.
Clouse and his colleague Dr. Gregory Sayuk, a Washington University gastroenterologist who specializes in irritable bowel syndrome and other functional digestive syndromes, are trying to understand how pain is processed in people with multiple functional syndromes. They have already shown that the pain processing center is more active in people with irritable bowel syndrome than in people without it.
Now they will compare how people such as Tina Allen, who have many functional syndromes, process pain with people who have only irritable bowel syndrome and with people who have no syndromes.
Allen, who is 50, made the trip from her home in Kansas City to participate in the study.
"I have believed my whole life that there's some sort of interference between my GI tract and my brain," she said. Her test results tell her she's not crazy. "I have quantifiable evidence of physical processes, so it's not just psychosomatic."
Sayuk expects to collect data on 24 volunteers by the end of the summer. It will take months to analyze the results.
More than 100 genes may be involved in making people with functional syndromes more sensitive to pain and stress, said UCLA's Mayer. As much as 20 percent of the population may carry genes that make them more susceptible to pain, Mayer said. But genes are not the whole story.
People who develop functional syndromes probably have some defect in their central nervous systems, Mayer said. Different events may trigger symptoms in different parts of the body, he said. Some studies have shown that people who get food poisoning are more likely to develop irritable bowel syndrome. Other things may trigger restless leg syndrome or pelvic pain or jaw pain.
Mayer predicts that within five years scientists will finally understand what drives functional syndromes. Finding treatments will probably take longer, but at least Allen and others may finally know what is wrong with them.