Senin, 03 November 2008

How infection can cause Irritable Bowel Syndrome?


IBS research on why and how infection causes IBS focuses on two areas:
  • How the inflammation that accompanies a bowel infection damages nerves in the gut lining and alters the way the gut nervous system works
  • How a low-grade inflammation remains in the gut following the infection In general, acute GI infections cause inflammation of the mucus membrane lining the intestines. They initiate a cascade of events that don’t stop when they’re supposed to. The inflammatory process seems to have a life of its own where immune cells infiltrate the intestinal lining and become a local irritant to the nervous system.
Consuming probiotics (good bacteria) either in yogurt or in capsule form is a worthwhile preventive measure when you have an episode of infectious diarrhea. Replacing your good bacteria that may be lost with continuous diarrhea may help to avoid the future development of IBS. The best types of probiotics are those that guarantee that each capsule contains one billion live organisms.

Blaming on the bowel infections


Sheila had a horrible stomach flu. She was laid up with vomiting, diarrhea, and fever for a week. After she recovered, she dragged herself to work but couldn’t seem to get her energy back. She was still having bouts of diarrhea four weeks later that didn’t seem to be improving. Her doctor told her not to worry because the problems would eventually go away. But eventually began to seem like forever to Sheila, and three months after the flu she was diagnosed with IBS.

Frank and his wife, Sally, went to Mexico for a much-needed vacation. Within three days they were both getting the runs and fighting for time in the bathroom. They took an antibiotic that the hotel doctor recommended, which seemed to sort things out for Frank. But Sally didn’t get much better. When they got home, Sally’s doctor (after several false starts with antidiarrhea medication) finally diagnosed parasites. The antiparasite medications were harsh, but after several weeks Sally was feeling somewhat better. However, she never completely recovered and was finally diagnosed with IBS. For some people with IBS, like Sheila and Sally, the cause can be identified definitively as a bowel infection. The infection may be due to either bacteria or parasites, and the IBS that results from it is called post-infectious IBS. (Something to keep in mind: Women seem to suffer more bowel symptoms for a longer period of time after a gastroenteritis attack than men).

According to a paper published in the journal Gut in 2003, chronic bowel turmoil resembling IBS develops in approximately 25 percent of patients after an episode of infectious diarrhea. The researchers admitted that the research community had previously shown that psychosocial factors operating at the time of, or prior to, the acute illness appeared to predict the development of post-infectious IBS. (As we explain in the previous section, many people have incorrectly placed the blame for IBS on stress.) The new research, however, showed an increased number of inflammatory cells in the rectum persisting for at least three months after the acute infection. The researchers concluded that there is definitely an organic component involved in the development of post-infectious IBS.

Confusions about Irritable Bowel Syndrome cause

Karen had been to several general practitioners regarding her symptoms of chronic diarrhea, pain, and bloating. She became increasingly dissatisfied with the treatment she was getting from doctors who were unable to make a diagnosis. As she was waiting for one doctor to come into the office, Karen took a peek at her chart and was alarmed by what she read. She saw the word hypochondriac in the notes. She realized she was never going to be diagnosed by doctors who simply didn’t believe her.
Doctors originally thought that IBS was caused by stress and emotional reactions. There was a yes, but approach to anyone with IBS: Yes, it’s a real condition, but people with IBS are really just anxious, depressed, and upset. The condition was equated with an overzealous nervous stomach, and it didn’t get much respect.
We do know that bouts of IBS may be triggered by. However, if stress is the cause of IBS, why wouldn’t 100 percent of the population have IBS instead of 20 percent? Quite frankly, IBS still doesn’t always get the respect it deserves. We found one 2004 survey of family doctors that indicates the majority of them believe people with IBS and chronic fatigue syndrome are simply slacking off and not pulling their weight in society. That bias can have serious consequences for people trying to obtain a diagnosis and treatment for IBS.
But the bias isn’t universal; most gastroenterologists (especially those who stay current with IBS research) now know that IBS is a very real condition. However, because IBS doesn’t have a single trademark sign or symptom to call its own, just knowing that it’s real doesn’t mean a doctor can easily diagnose it.

Triggers and associated conditions of Irritable Bowel Syndrome

Triggers:
• Food allergy or sensitivity
• Antibiotics
• Stress
• Candida albicans

Associated conditions:
• Fibromyalgia
• Insomnia
• Painful periods
• Urinary frequency
• Chronic pelvic pain

These conditions are experienced mostly by women (especially the painful periods!). Fortunately, most experts agree that IBS is not associated with inflammatory bowel disease (Crohn’s disease or ulcerative colitis, which we discuss in this chapter) or cancer.

Possible causes of Irritable Bowel Syndrome

Several possible causes of IBS are being considered:
  • Use of analgesics: In survey studies, researchers have found that acetaminophen, the ingredient in Tylenol, has been frequently used by people who develop IBS-diarrhea. This drug is known to cause elevated levels of serotonin, and research indicates that serotonin may become elevated in patients with IBS-diarrhea after eating
  • Brain-bowel chemical imbalance: The brain and the gut are intimately connected by both the nervous system and by neurotransmitter chemicals, such as serotonin and norepinephrine. Both chemicals may be involved with the production of IBS symptoms. So far, we know that diarrhea can occur when high amounts of serotonin inhibit norepinephrine and cause levels of acetylcholine to increase. On the other hand, when norepinephrine levels increase, the result is constipation, as well as a lowering of serotonin levels and blockage of acetylcholine. For IBS patients, this chemical dance may lead to the fluctuating bowel symptoms of constipation and diarrhea. But we must ask what the cause of the imbalance is in the first place.
  • Female hormones: Considering that men don’t have high amounts of female hormone, and men do suffer from IBS, female hormones are not the cause of IBS. However, women have twice the incidence of IBS as men.