Short Bowel Syndrome
Short-bowel syndrome is a disorder clinically defined by
malabsorption, diarrhea, steatorrhea, fluid and electrolyte
disturbances, and malnutrition. The final common etiologic factor
in all causes of short-bowel syndrome is the functional or anatomic
loss of extensive segments of small intestine so that its ability
to absorb is severely compromised.
Few conditions in pediatric gastroenterology pose as great a
challenge as short bowel syndrome (SBS). It represents a complex
disorder that affects normal intestinal physiology with
nutritional, metabolic, and infectious consequences.
The small intestine is completely formed by 20 weeks' gestation.
Most of its growth prior to birth occurs in the third trimester.
Before 27 weeks' gestation, the average length of the small
intestine is 115 cm. This length increases to approximately 250 cm
with a diameter of 1.5 cm after 35 weeks' gestation. In contrast,
the adult intestine is 600 to 800 cm in length and 4 cm in
diameter. The mucosal surface area increases with age. Infants have
950 square cm; adults have 7500 square cm.
The intestine has an enormous capacity to absorb secretions and
ingested fluids. There is extra intestine normally which is why a
major loss of the intestine may not result in SBS. Absorption
occurs through the lining (mucosa) of the small intestine.
Nutrients, vitamin B12, calcium, iron, and bile acids are absorbed
through the cells of this lining. Mucus covers the surface of the
mucosa cells and acts as a trap to hold nutrients in contact with
the cell surface. Mucus also acts as a bacterial barrier.
What is Short Bowel Syndrome?
Short bowel syndrome, also refered to as SBS, or short gut
syndrome, short bowel state or simply short gut is a disorder
clinically defined by poor absorbtion of food, diarrhea and
malnutrition. Simply this means where a significant amount of bowel
(half or more of the small intestine) is lost, removed, or unable
to function inside the body and medical intervention is required in
order for the child to survive.
What causes short bowel syndrome?
The most common causes of short bowel syndrome in infants is as
- Necrotising enterocolitis (NEC) - an infection or inflammation
(swelling) of the intestine of premature babies that can lead to
the dying (necrosis) of the intestinal tract.
- Gastroschisis - congenital (before birth) defect where a hole
develops in the abdominal (stomach area) wall causing some of the
bowel to escape through the hole and continue to develop on the
outside of the baby's abdomen.
- Malrotation - a congenital (before birth) abnormality of the
- Volvulus - a complication of malrotation where the bowel twists
and the blood supply to the bowel is cut off.
- Intestinal atresia's - malformation where there is a narrowing
or absence of a portion of the intestine
- Bowel injury - from trauma
All these causes make digestion and absorbtion of food unable to
take place and the body cannot obtain the essential nutriants to
stay healthy without artificial drip feeding(see TPN and
Nutrition). Not all patients who lose significant amounts of gut
develop short-bowel syndrome.
- Other factors that determine if a patient will be affected
- The length of the bowel before any disease or complication