Definition of Blind loop syndrome:

Blind loop syndrome occurs when part of the intestine becomes bypassed, so that digested food slows or stops moving through the intestines. This causes bacteria to grow too much in the intestines and leads to problems in absorbing nutrients.

Causes, incidence, and risk factors:

The name of this condition refers to the "blind loop" formed by the bypassed intestine. This blind loop does not allow digested food to flow normally through the intestinal tract.

When a section of the intestine is affected by blind loop syndrome, the bile salts needed to digest fats become ineffective. This leads to in fatty stools and poor absorption of fat and fat-soluble vitamins. Vitamin B12 deficiency may occur because the extra bacteria that develop in this situation use up all of the vitamin.

Blind loop syndrome is a complication that occurs:

• After many operations, including subtotal gastrectomy (surgical removal of part of the stomach) and operations for extreme obesity
• As a complication of inflammatory bowel disease

Diseases such as diabetes or scleroderma may slow down movement in a segment of the intestine, leading to blind loop syndrome.

Symptoms:

• Diarrhea
• Fatty stools
• Fullness after a meal
• Loss of appetite
• Nausea
• Unintentional weight loss

Signs and tests:

During a physical examination, the doctor may notice a mass in, or swelling of, the abdomen. Possible tests include:

• Abdominal CT scan
• Abdominal x-ray
• Contrast enema study

Treatment:

Treatment generally starts with antibiotics for the excess bacteria growth, along with vitamin B12 supplements. If antibiotics don't work, surgery to help the food flow through the intestine may be considered.

Expectations (prognosis):

Many patients get better with antibiotics. If surgical repair is required, the outcome is typically very good.

Complications:

• Complete intestinal obstruction
• Death of intestine (intestinal infarction)
• Hole (perforation) in intestine
• Malabsorption and malnutrition

Calling your health care provider:

Call your health care provider if you have symptoms of blind loop syndrome.