Short bowel syndrome
Other names: Short gut syndrome, short gut, intestinal failure
A piece of diseasedileum following removal by surgery.
Specialty	Gastroenterology
Symptoms	Diarrhea,dehydration,malnutrition,weight loss[1]
Complications	Anemia,kidney stones[2]
Causes	Surgical removal of a large portion of thesmall intestine[1]
Risk factors	Crohn's disease,necrotising enterocolitis[2]
Treatment	Specific diet, medications, surgery[1]
Medication	Antibiotics,antacids,loperamide,teduglutide,growth hormone[1]
Prognosis	Depends on amount of small bowel remaining[2]
Frequency	3 per million per year[1]

Short bowel syndrome (SBS, or simplyshort gut) is amalabsorption disorder caused by a lack of functionalsmall intestine.^[3] The primary symptom isdiarrhea, which can result indehydration,malnutrition, andweight loss.^[1] Other symptoms may include bloating,heartburn, feeling tired,lactose intolerance, and foul-smelling stool.^[1] Complications can includeanemia andkidney stones.^[2]

Most cases are due to the surgical removal of a large portion of the small intestine.^[1] This is most often required due toCrohn's disease in adults andnecrotising enterocolitis in young children.^[2] Other causes include damage to the small intestine from other means and being born with an abnormally short intestine.^[1] It usually does not develop until less than 2 m (6.6 ft) of the normally 6.1 m (20 ft) small intestine remains.^[3][1]

Treatment may include a specific diet, medications, or surgery.^[1] The diet may includeslightly salty and slightly sweet liquids, vitamin and mineral supplements, small frequent meals, and the avoidance of high fat food.^[1] Occasionally nutrients need to be given through anintravenous line, known asparenteral nutrition.^[1] Medications used may includeantibiotics,antacids,loperamide,teduglutide, andgrowth hormone.^[1] Different types of surgery, including anintestinal transplant, may help some people.^[1]

Short bowel syndrome newly occurs in about three per million people each year.^[1] There are estimated to be about 15,000 people with the condition in the United States.^[2] It is classified as arare disease by theEuropean Medicines Agency.^[4] Outcomes depend on the amount of bowel remaining and whether or not the small bowel remains connected with the large bowel.^[2]

Signs and symptoms

The symptoms of short bowel syndrome can include:

• Abdominal pain
• Diarrhea andsteatorrhea (oily, bulky stool, which can be malodorous)
• Fluid depletion
• Weight loss andmalnutrition
• Fatigue

Persons with short bowel syndrome may have complications caused by malabsorption of vitamins and minerals, such asdeficiencies in vitaminsA,D,E,K,B₉ (folic acid), andB₁₂,calcium,magnesium,iron, andzinc. These may appear asanemia,hyperkeratosis (scaling of the skin), easybruising, musclespasms, poorblood clotting, andbone pain.

Causes

Short bowel syndrome in adults and children is usually caused by surgery. This surgery may be done for:

• Crohn's disease, an inflammatory disorder of the digestive tract
• Volvulus, a twisting of the small intestine often caused byintestinal malrotation that quickly cuts off blood supply and leads to tissue death
• Tumors of the small intestine
• Injury or trauma to the small intestine
• Necrotizing enterocolitis (premature newborn)
• Bypass surgery to treat obesity
• Surgery to remove diseases or damaged portion of the small intestine

Some children are also born with an abnormally short small intestine, known as congenital short bowel.^[1]

Pathophysiology

The length of the small intestine can vary greatly, from as short as 2.75 m (9.0 ft) to as long as 10.49 m (34.4 ft).^[5] On average it is about 6.1 m (20 ft).^[1] Due to this variation it is recommended that following surgery the amount of bowel remaining be specified rather than the amount removed.^[5]

Short bowel syndrome usually develops when there is less than 2 meters (6.6 feet) of the small intestine left to absorb sufficientnutrients.

In a process called intestinal adaptation, physiological changes to the remaining portion of the small intestine occur to increase its absorptive capacity. These changes include:

• Enlargement and lengthening of thevilli found in the lining
• Increase in the diameter of the small intestine
• Slow down in peristalsis or movement of food through the small intestine

Diagnosis

Definition

Intestinal failure is decreased intestinal function such that nutrients, water, and electrolytes are not sufficiently absorbed. Short bowel syndrome is when there is less than 2 m (6.6 ft) of working bowel and is the most common cause of intestinal failure.^[3]

Treatments

Symptoms of short bowel syndrome are usually addressed with medication. These include:

• Anti-diarrheal medicine (e.g.loperamide,codeine)
• Vitamin, mineral supplements andL-glutamine powder mixed with water
• H2 blocker andproton pump inhibitors to reduce stomach acid
• Lactase supplement (to improve the bloating and diarrhoea associated withlactose intolerance)

In 2004, theUSFDA approved a therapy that reduces the frequency and volume oftotal parenteral nutrition (TPN), comprising:NutreStore (oral solution of glutamine) and Zorbtive (growth hormone, ofrecombinant DNA origin, for injection) together with a specialized oral diet.^[6] In 2012, an advisory panel to the USFDA voted unanimously to approve for treatment of SBS the agentteduglutide, aglucagon-like peptide-2 analog developed byNPS Pharmaceuticals, who intend to market the agent in the United States under the brandname Gattex.^[7] Teduglutide had been previously approved for use in Europe and is marketed under the brand Revestive byNycomed.^[7]

Surgical procedures to lengthen dilated bowel include the Bianchi procedure, where the bowel is cut in half and one end is sewn to the other, and a newer procedure calledserial transverse enteroplasty (STEP), where the bowel is cut and stapled in a zigzag pattern. Heung Bae Kim, MD, and Tom Jaksic, MD, both of Children's Hospital Boston, devised the STEP procedure in the early 2000s. The procedure lengthens the bowel of children with SBS and may allow children to avoid the need for intestinal transplantation. As of June 2009, Kim and Jaksic have performed 18 STEP procedures.^[8] The Bianchi and STEP procedures are usually performed by pediatric surgeons atquaternary hospitals who specialize in small bowel surgery.

Prognosis

There is no cure for short bowel syndrome excepttransplant. In newborn infants, the 4-year survival rate on parenteral nutrition is approximately 70%. In newborn infants with less than 10% of expected intestinal length, 5 year survival is approximately 20%.^[9] Some studies suggest that much of the mortality is due to a complication of the total parenteral nutrition (TPN), especiallychronic liver disease.^[10] Much hope is vested inOmegaven, a type of lipid TPN feed, in which recent case reports suggest the risk of liver disease is much lower.^[11]

Although promising,small intestine transplant has a mixed success rate, with postoperative mortality rate of up to 30%. One-year and 4-year survival rate are 90% and 60%, respectively.

See also

• Bowel-associated dermatosis–arthritis syndrome, another syndrome that can result from small-bowel bypass

References

External links

• Short bowel syndrome atCurlie
• National Digestive Diseases Information Clearinghouse - Short Bowel SyndromeArchived 2014-03-21 at theWayback Machine

• Pages with script errors
• Articles with Curlie links
• Webarchive template wayback links
• Syndromes
• Diseases of intestines
• Steatorrhea-related diseases
• RTT
• RTTEM