What causes short bowel syndrome?

summary

Short bowel syndrome refers to the malabsorption syndrome in which the residual functional bowel cannot maintain the nutritional needs of patients after extensive small bowel resection (including partial colectomy). It is characterized by severe diarrhea, weight loss, progressive malnutrition and disorder of water and electrolyte metabolism, which affects the development of the body and has a high mortality rate. At present, nutritional support and small bowel transplantation are the main treatment methods, but the curative effect is uncertain. The quality of life of patients still depends on the remaining small bowel length and its functional status. What causes short bowel syndrome?

What causes short bowel syndrome?

There are many different causes of adult short bowel syndrome in adults (Table 1), mainly due to mesenteric vascular embolism or thrombosis, and acute volvulus leading to extensive small bowel resection (75% or more). The causes of mesenteric vascular embolism or thrombosis are: old age, chronic congestive heart failure, atherosclerosis and heart valve disease, long-term use of diuretics, hypercoagulable state, oral contraceptives; Short bowel syndrome can also occur in morbidly obese patients with jejuno ileal short circuit surgery; The rare causes of short bowel syndrome are: abdominal injury, primary or secondary intestinal tumor, radiation intestinal lesions; Rare cases are: medical errors in the treatment of peptic ulcer stomach ileum anastomosis, resulting in clinical symptoms similar to extensive small bowel resection.

The etiology of short bowel syndrome in children can be divided into pre - and postnatal causes (Table 1). The main cause before birth is intestinal atresia. Ectopic fixation or abnormal torsion of the small intestine caused by malrotation of the midgut can occur in the uterus or at any time after birth; Neonatal necrotizing enteritis is increasing, which has been considered as the main cause of neonatal short bowel syndrome. In addition, the rare factors after birth are Hirschsprung's disease involving small intestine, mesenteric vascular embolism or thrombosis. Radiation enteritis or Crohn's disease can also cause this syndrome, but it mainly exists in older children.

After extensive small bowel resection, a series of pathophysiological changes will occur in the digestive tract function, leading to a group of syndromes with malnutrition as the main symptom. The severity of the syndrome depends on the following factors: the scope and location of the resection of the intestinal tract; the location of the intestinal tract; the location of the intestinal tract; Whether to keep the ileocecal valve or not; The functional status of residual intestinal tract and other digestive organs (such as pancreas and liver); The compensatory ability of the remaining small intestine and large intestine.

matters needing attention

The most important factors for the occurrence of this disease are the extent of resection and the site of small intestine resection. When the resection of small intestine reaches or exceeds 50%, significant malabsorption can occur. More than 70% of the patients can have severe symptoms or even death. Duodenum, proximal jejunum and distal ileum are the main intestinal segments for digestion and absorption of small intestine, As long as the above intestinal segments are preserved, even 50% of the patients with resection of the middle small intestine can still tolerate it. However, if 2 / 3 of the distal ileum is resected or 25% of the ileocecal valve and jejunum are resected, severe diarrhea and malabsorption can be caused. Therefore, in the implementation of small bowel resection, the patient's life is basically safe, It is an important measure to keep the main part of the small intestine as much as possible, and to have a sufficient length of active intestinal tube is an important measure to reduce the occurrence of this disease, which is a common factor affecting short bowel syndrome.