Short Gut Syndrome Causes and Treatment

Short Gut Syndrome

Causes of Short Gut Syndrome:

• Short gut syndrome occurs due to massive resection of the bowel resulting in loss of length of the bowel, loss of absorptive area of the bowel and loss of valves. Superior mesenteric artery being an end artery, thrombosis at its origin is invariably fatal.
• Midgut volvulus of neonates is congenital due to arrested rotation resulting in floating caecum and mobile intestine. We had an interesting case of midgut volvulus in an 18-year-old boy consequent to a laparotomy done for perforated duodenal ulcer. While replacing the coils of bowel within the abdomen, the mesentery was probably twisted resulting in massive gangrene. This boy now has about 100 cm of the small bowel.
• Necrotising enteritis (enteritis necroticans) is a complication of infection of small bowel by Clostridium perfringens. It usually occurs after a heavy feast where pork is consumeThere is extensive suppuration of mucosal and submucosal layer of jejunum (also ileum). Serosa may show multiple dark bluish patches. Massive resection is done for a necrotic, perforated, unhealthy bowel which results in short gut syndrome.
• Radiation enteritis or radiation enteropathy results in patients who receive radiotherapy to the abdominal and pelvic regions, e.g. carcinoma cervix. Arrest of cell division resulting in mucosal thinning, ulceration followed by oedema and later, fibrosis are characteristics of this condition. Endarteritis and vasculitis also add to these changes resulting in stricture, perforations, abscess, malabsorption and multiple resection, etc.

Short Gut Syndrome Pathophysiological Effects:

It depends upon:

• Extent of resection
• Site of resection
• Presence/absence of ileocaecal valve
• Age of the patients
• Infants tolerate extensive resections better than adults. Patients with less than 100 cm of the small bowel will develop severe nutritional deficiencies and may require parenteral nutrition.
  • Malabsorption of fat and fat-soluble vitamins: Can occur after ileal resections due to interruption of enterohepatic circulation of bile salts. These bile salts enter the colon and are converted into secondary bile salts. These bile salts block absorption of water and electrolytes.
  • Gastric hypersecretion: Due to delayed clearance of gastrin, as in proximal jejunal resections, there is increased gastric secretion of acid resulting in hyperacidity.
  • Liver disease: Fatty infiltration of the liver and mild hyperbilirubinaemia are seen massive resections and jejunoileal bypass. Acute fulminant hepatic failure can also occur.

• • Gallstone formation: There is an increased incidence of cholesterol stones as a result of reduced bile salt pool, after ileal resection and jejunoileal bypass.
  • Urinary stones:
    • All types of urinary stones are common due to low levels of calcium excretion in the urine and high levels of oxalate.
    • Water and salt depletion and loss of K+ cause hyponatraemia and hypokalaemia.

Short Gut Syndrome Adaptation:

As a result of loss of significant bowel, dilatation of the remaining intestine and villous enlargement takes place. This is brought about by a humoral agent, enteroglucagon. In children, the length of the bowel is increased, the number of cells in the villi is increased (work hypertrophy). There is also evidence to suggest a gradual slowing of the transit time.

Short Gut Syndrome Treatment:

• Treatment of short gut patients is difficult. It needs a special set up of dieticians who plan ‘proper food’ for these patients in consultation with treating surgeons. It is a gradual process of feeding the patient beginning with parenteral nutrition and progressing to a normal, low-fat diet after a few months.
• In the initial 2–3 months following massive resection, total parenteral nutrition including supplementation of fluid and electrolytes is the ideal treatment. Sips of plain water or oral hypotonic solutions can be allowed.
• After 2–3 months, when an adaptation of the bowel takes place, enteral feeding is started gradually with baby food, fat-free, fibre-free, protein-rich, liquid diet. Essential fatty acids should be supplieDiarrhoea is a common problem and is treated with loper amide tablets.
• Enteral feeding can contain low fatty diet in addition to the other nutrients mentioned above.
• Small bowel transplantation is also being done when all measures fail specially when the bowel length is less than 50 cm.