malabsorption syndrome after gastrectomy
Introduction
Introduction to malabsorption syndrome after gastrectomy Most patients with gastrectomy recovered better, but after gastric resection, the patient was malabsorbed, malnourished, and the weight loss was common. Post-gastric resection syndrome (postgastrectomymalabsorptionsyndrome) occurred. basic knowledge The proportion of the disease: the disease belongs to the complication of most of the stomach resection, the incidence of this disease after the majority of gastric resection is about 20% Susceptible people: no special people Mode of infection: non-infectious Complications: malnutrition Osteoporosis
Cause
Causes of malabsorption syndrome after gastrectomy
(1) Causes of the disease
Causes of absorption of digestive tract after gastrectomy:
1. Impaired stomach skills and accelerated gastric emptying.
2. The bile and pancreas secretion is not synchronized after the meal.
3. Changes in several factors in the small intestine after gastric resection can lead to malabsorption syndrome.
(two) pathogenesis
1. Impaired gastric function and gastric emptying accelerate gastric acid after gastric resection, decrease of pepsin secretion, rapid gastric emptying, weakened food digestion, duodenal bypass, food directly into the small intestine, lack of stimulation of pancreaticobiliary secretion or Decreased, CCK release decreased, bile salt, lipase, trypsin concentration decreased in the proximal small intestine contents, chyme and bile salts, pancreatic enzymes were incompletely mixed, and fat emulsification was insufficient, resulting in malabsorption.
2. Postprandial pancreas, bile secretion, non-synchronized liquid test meal, study on the effects of biliary and pancreatic secretion after gastric surgery:
(1) Gastric emptying after gastric resection is accelerated: the normal control group needs 75.3 min after gastric emptying in the liquid test meal; Billroth I, II gastric resection patients only need 43.1 min, 44.3 min.
(2) In the normal control group, the trypsin concentration in the proximal jejunal fluid increased from 21 U/ml to 50 U/ml after 20-30 min after the liquid test meal, and the trypsin concentration remained stable at a high level after 2 h; and Billroth II In patients with gastrectomy, the trypsin concentration in the proximal jejunal fluid was lower than that in the normal control group after 20 to 30 minutes of liquid test, and the trypsin concentration in the fasting jejunal digestive juice began to rise slowly after 50 minutes of the liquid test meal. Billroth I stomach Excision of the patient over the normal control group, in order to rule out the effect of gastric emptying after gastric resection on the dilution of trypsin concentration, after the CCK of patients after Billroth I, II surgery, the trypsin concentration in the proximal jejunal digestive juice was detected, suggesting Billroth I, II The concentration of trypsin in the proximal jejunal digestive juice of the patient was the same as that in the normal control group after surgery, indicating that the secretion decreased after gastric resection resulted in a decrease in trypsin concentration in the jejunal digestive juice.
(3) After the operation of Billroth I, II, the concentration of bile salts in the proximal jejunal digestive juice of the patients after the liquid test was lower than that of the normal control group. The imbalance of pancreaticobiliary secretion after the meal constituted a relatively insufficient pancreatic function and decreased the concentration of cholate. , leading to a decrease in the absorption capacity of fats, sugars, and proteins.
3. Intestinal factors Several factors in the small intestine after gastrectomy can lead to malabsorption syndrome, including:
(1) Accelerated delivery of small intestine: loss of absorption time of proximal small intestine and poor absorption of glucose.
(2) Lactose deficiency in the small intestine reduces lactose tolerance.
(3) Bacterial growth in the small intestine:
1 Increased bacterial count in the small intestine after gastrectomy: the incidence of bacterial neoplasia in the small intestine of Billroth II gastric resection patients is 30% to 50%, the normal upper jejunum bacteria count 104/ml, gastric sinusectomy, vagus nerve stemectomy and most gastric resection The bacteria count in the upper jejunum was 108-109/ml.
2 The number of bacteria in the small intestine increased after gastric resection: only 2 to 3 strains of normal jejunum, mainly G+ cocci, facultative anaerobic lactic acid bacteria, non-anaerobic Bacteroides, especially after patients with blind sputum syndrome after gastric resection, The jejunal digestive juice is accompanied by a variety of aerobic and anaerobic bacteria that are usually parasitic in the colon. This small intestinal environment changes and gastric acid secretion decreases after gastric resection, intestinal motility changes, and the peristaltic complex wave during the small intestine digestion is lost. The scavenger function is related.
3 The effect of bacterial growth on intestinal absorption in the small intestine: bacterial growth in the small intestine causes monosaccharide in the intestinal lumen, and active transport of amino acids into the cells is impaired. Gianella studies have demonstrated bacterial growth in the small intestine after gastric resection, and intestinal villus to glucose and leucine Loss of transport function, vitamin B12 decline, with antibiotics can make these changes partially corrected, demonstrating the negative impact of bacterial growth in the small intestine on carbohydrates, protein absorption.
4 The effect of bacterial growth in the small intestine on bile acid metabolism: fat and its fat-soluble vitamin must be mixed with bile salt to form a bile salt micelle. When the bacteria in the small intestine are excessively axillary, the bacteria in the small intestine can be Primary bile acid is converted to secondary bile acid (ie, cholic acid, deoxycholic acid, chenodeoxycholic acid, lithocholic acid), and secondary bile acid does not participate in bile salt microcapsule configuration, thereby failing to form fatty acids, monoglycerides , lecithin and cholesterol, fat-soluble vitamins mixed with micelles (mixed micelle) are absorbed, resulting in malabsorption of fat and fat-soluble vitamins.
Prevention
Prevention of malabsorption syndrome after gastrectomy
Pay attention to rest, work and rest, life in an orderly manner, and maintaining an optimistic, positive and upward attitude towards life can be of great help in preventing diseases.
Complication
Complications of malabsorption syndrome after gastrectomy Complications, malnutrition, osteoporosis
Malabsorption after gastrectomy often leads to complications such as malnutrition, weight loss, weight loss, and osteoporosis.
Symptom
Symptoms of malabsorption syndrome after gastrectomy Common symptoms Small stomach syndrome, stomach acid reduction, diarrhea, malabsorption syndrome, osteoporosis, gastric emptying, fast, wasting, dumping syndrome, iron deficiency anemia, steatorrhea
1. Malnutrition: Small stomach syndrome, discomfort after eating causes the patient to be in a state of semi-starvation for a long time, and the dumping syndrome and malabsorption of the gastrointestinal tract cause the patient to lose weight and malnutrition.
2. Anemia: due to postoperative gastric acid reduction, affecting the absorption of iron, leading to iron deficiency anemia, due to lack of anti-anemia factors after gastric resection, resulting in vitamin B12 malabsorption, leading to megaloblastic anemia.
3. Diarrhea: Due to the II type anastomosis, the gastric emptying is too fast, the small bowel movement is enhanced, digestion and malabsorption are caused, and the food and bile, the pancreatic juice can not be well mixed, and the emulsification of the pancreatic juice to break down fat and bile salts is lost. Fat action, affecting fat absorption, leading to steatorrhea.
4. Osteopathy: 5 to 10 years after surgery, osteomalacia is more common, severe cases can cause osteoporosis, the main symptoms are bone pain, lower extremity weakness, easy fracture, etc. No longer passes through the duodenum, calcium absorption is reduced, and fat malabsorption also affects the absorption of fat-soluble vitamin D.
In order to rule out the deficiency of pancreatic function, the malabsorption caused by special causes such as sputum syndrome, gastric jejunal colon fistula, gastric ileal mismatch anastomosis, etc., in addition to routine blood test, should be used for upper digestive tract barium meal, barium enema and digestive tract endoscopy .
Examine
Examination of malabsorption syndrome after gastrectomy
1. Blood routine: The total amount of hemoglobin in the blood is reduced due to anemia.
2. Intestinal absorption function test:
(1) Determination of fat globules, nitrogen content, muscle fiber and chymotrypsin content in feces: When the fat globule is more than 100 in the high-power field of the microscope (Sultan III staining), fat malabsorption may be considered; when the nitrogen content in the feces increases, Considering the absorption of carbohydrates; the increase of muscle fibers in feces and the decrease in chymotrypsin content suggest poor intestinal absorption.
(2) D-xylose test: D-xylose excretion in urine is often reduced in patients with poor intestinal absorption.
(3) Radionuclide labeled vitamin B12 absorption test (Schilling test): In the small intestine absorption dysfunction, the urinary radionuclide content is significantly lower than normal.
Should be used for digestive tract barium meal, barium enema and endoscopy.
Diagnosis
Diagnosis and identification of malabsorption syndrome after gastrectomy
Diagnostic criteria
Diagnosis of bacterial growth in the small intestine:
1. Duodenum, upper jejun digestive juice bacterial culture: the advantage is that the number of bacteria can be directly determined, the disadvantages are invasive and easy to be contaminated.
2.14C-glycocholate breath test: oral administration of 5UCi l4C glycocholate to patients, 14C glycine decomposed by bacteria in the small intestine, 14C glycine by bacterial enzymes, metabolism in the intestinal lumen produces 14CO2, absorbed through the intestinal mucosa Blood, after oral administration of 14C glycocholate 1h, 14CO2 exhaled through the lungs, exhaled 14CO2 can be directly measured, exhaled 14CO2 increase means no increase in bile acid, no increase in bile acid may be due to excessive production of intestinal bacteria, intestinal bacterial growth In patients with syndrome, exhaled 14CO2 is 10 times larger than normal, so the 14C glycochaldate breath test is helpful for over-diagnosis of bacterial hyperplasia in the small intestine after gastrectomy.
3.14C xylose breath test: xylose is mainly absorbed in the proximal jejunum. If the decomposition increases, it indicates excessive bacterial overgrowth in the small intestine. In patients with intestinal bacterial syndrome, the increase of 14CO2 in the exhaled breath within 60 minutes after the test begins. It is considered to be the first choice for the diagnosis of intestinal bacterial syndrome, and has good sensitivity and specificity.
Differential diagnosis
1. Chronic hepatobiliary diseases: such as chronic hepatitis, cirrhosis and intrahepatic bile duct obstruction, etc., due to the lack of bile salts, fat can not be emulsified and transported, it can lead to steatorrhea.
2. Small bowel disease: excessive small intestine resection (such as short bowel syndrome when the small intestine is removed more than 75% of the total length or only 120cm remaining), stomach, colon fistula or stomach, ileal fistula can be due to the absorption area of the small intestine Decrease, or food that passes through the small intestine or jejunum and through the fistula to the colon, can eventually lead to diarrhea.
