Blind loop syndrome
Blind loop syndrome
Blind loop syndrome occurs when part of the small intestine is bypassed and cut off from the normal flow of food and digestive juices.
The bypassed portion of intestine, known as a blind loop, leads to a series of problems. Food can't pass through the loop, and digestive fluids stagnate. As a result, food ferments, encouraging bacterial growth and interfering with absorption of essential nutrients. Blind loop syndrome often leads to diarrhea, weight loss and malnutrition.
Blind loop syndrome — sometimes called stasis syndrome or stagnant loop syndrome — often occurs as a complication of abdominal surgery. But blind loop syndrome can also result from structural defects and some diseases. Although blind loop syndrome occasionally requires surgery, most people respond well to antibiotics.
Because blind loop syndrome affects digestion and absorption of nutrients, signs and symptoms of the disorder often include:
When to see a doctor
If you have severe abdominal pain, get immediate medical care.
Although digestion begins in your mouth, the real work of breaking down and absorbing nutrients takes place in your small intestine, the longest section of your digestive tract measuring about 20 feet (6.1 meters). Connecting your stomach and large intestine, your small intestine is where food mixes with digestive juices from your stomach, pancreas, liver and gallbladder, and where small nutrient molecules — amino acids from proteins, monosaccharides from carbohydrates and most fats — are absorbed into your bloodstream.
Unlike your large intestine (colon), which has billions of bacteria to help break down indigestible fiber, your small intestine normally contains relatively few microorganisms. Because your small intestine is rich in enzymes, it doesn't need the enzymatic action of bacteria. In fact, stomach acid and secretions from your liver and pancreas actually act as antibacterial agents. What's more, the strong muscular contractions (peristalsis) that propel food through your small intestine prevent bacteria from colonizing there.
But in blind loop syndrome, food can't move through the bypassed section of intestine, and the stagnant food becomes an ideal breeding ground for microorganisms — a condition called bacterial overgrowth syndrome. The bacteria may produce toxins as well as interfere with the absorption of nutrients. The greater the length of small bowel involved in the blind loop, the greater the degree of bacterial overgrowth.
What triggers blind loop syndrome
Your digestive tract stretches from your mouth to your anus. It includes the organs necessary to digest food and process waste. ...
Factors that increase your risk of bacterial overgrowth in the small intestine include:
A blind loop can cause an escalating series of problems, including:
Preparing for your appointment
If you have signs and symptoms that are common to bile loop syndrome, make an appointment with your doctor. After an initial evaluation, you may be referred to a doctor who specializes in the diagnosis and treatment of digestive disorders (gastroenterologist).
Here's some information to help you get ready for your appointment, and what to expect from your doctor.
Information to gather in advance
For blind loop syndrome, some basic questions to ask your doctor include:
In addition to the questions that you've prepared to ask your doctor, don't hesitate to ask questions at any time that you don't understand something.
What to expect from your doctor
Tests and diagnosis
The first step in diagnosing blind loop syndrome is usually an imaging test, such as:
You may also have additional tests to check for bacterial overgrowth in your small intestine, for poor fat absorption, or for other problems that may be causing or contributing to your symptoms:
In some cases, when the likelihood of bacterial overgrowth is high, your doctor may begin treatment with antibiotics immediately without specific testing (empiric therapy).
Treatments and drugs
Whenever possible, doctors treat blind loop syndrome by dealing with the underlying problem — surgically repairing a postoperative blind loop, stricture or fistula, for example. But, the blind loop can't always be reversed. In that case, treatment focuses on correcting nutritional deficiencies and eliminating bacterial overgrowth.
Doctors may also switch among different drugs to help prevent bacterial resistance. Ironically, because antibiotics wipe out most intestinal bacteria — both normal and abnormal — they can cause some of the very problems they're trying to cure, including diarrhea and an imbalance of bacteria in the digestive tract.
The following measures may improve vitamin deficiencies, reduce intestinal distress and help with weight gain:
Last Updated: 2010-01-19
© 1998-2013 Mayo Foundation for Medical Education and Research (MFMER). All rights reserved. A single copy of these materials may be reprinted for noncommercial personal use only. "Mayo," "Mayo Clinic," "MayoClinic.com," "Mayo Clinic Health Information," "Reliable information for a healthier life" and the triple-shield Mayo logo are trademarks of Mayo Foundation for Medical Education and Research.
Terms and conditions of use