malabsorption syndrome
Introduction
Introduction to malabsorption syndrome Absorption syndrome is a syndrome caused by malabsorption of small intestine nutrients for various reasons. The absorption of nutrients must be fully digested. Therefore, the generalized malabsorption syndrome includes indigestion and malabsorption, so it is also called "digestive malabsorption syndrome". Many diseases can cause this syndrome, but their clinical manifestations and experimental findings are often similar. Absorption is a variety of nutrients, of which fat absorption disorders are the most characteristic. basic knowledge The proportion of illness: 0.12% Susceptible people: no specific population Mode of infection: non-infectious Complications: diarrhea, hypotonic dehydration, angular keratitis, nutritional anemia
Cause
Cause of malabsorption syndrome
Cause (35%):
Insufficient secretion of bile or pancreatic juice, excessive bacterial growth in the small intestine, intestinal dyskinesia, intestinal blood circulation or lymphatic circulation disorder, lesions of the small intestine itself, and loss of on-site mucosa.
Prevention
Malabsorption syndrome prevention
There is no effective preventive measure for primary malabsorption syndrome. For the malabsorption caused by biliary system and pancreatic diseases, the treatment of primary disease should be paid attention to. The improper treatment of gastrointestinal surgery is also an important factor causing digestion and malabsorption. Therefore, surgical wounds should be treated with caution, and attention should be paid to the prevention of infections such as parasites.
Complication
Malabsorption syndrome complications Complications, diarrhea, hypotonic dehydration, angular keratitis, nutritional anemia
1. Water and electrolyte disorders Patients with this disease often have hypoproteinemia, increased total fluid volume, making the extracellular fluid hypotonic, when vomiting, diarrhea, easy to cause hypotonic dehydration and serious dielectric disturbance, resulting in low Blood potassium, hyponatremia, hypocalcemia and hypomagnesemia cause symptoms.
2. Often accompanied by other nutrient deficiencies, especially vitamin A deficiency, corneal dryness and softening, and even perforation, often accompanied by vitamin B deficiency caused by angular keratitis, due to growth retardation, it is rare snoring, Often accompanied by nutritional anemia.
3. Due to low systemic immune function, it is easy to develop a variety of acute and chronic infections and infectious diseases, especially intestinal and respiratory infections, easy to spread measles, tuberculosis and other infectious diseases and parasitic diseases, digestive tract or systemic fungal infections are not Rarely, once the infection has often prolonged, Gram-negative bacilli enteritis, sepsis or urinary tract infections are often difficult to cure.
Symptom
Symptoms of malabsorption syndrome Common symptoms Abdominal pain Abdominal discomfort Abdominal syndrome Abdominal bloating Abdominal fatigue Weaning sucrose-I maltose... Loss of appetite
Malabsorption syndrome causes a series of pathophysiological changes due to nutrient, vitamin and electrolyte absorption disorders. The main clinical manifestations are:
1. Diarrhea and other gastrointestinal symptoms
Diarrhea is the main symptom, and the most characteristic, daily defecation 3-4 times or more, more feces, no shape, light color with oily luster or foam, stench, watery diarrhea, a few mild Or atypical cases may have no diarrhea, accompanied by abdominal belching, abdominal distension, abdominal discomfort, but rarely abdominal pain, some patients may have loss of appetite and nausea, vomiting.
Second, nutritional deficiency symptoms
After diarrhea occurs, due to protein loss and insufficient heat supply, patients gradually become weak, weight loss, weight loss, anemia, lower extremity edema, and hypoproteinemia.
Third, vitamin and electrolyte deficiency symptoms
Different degrees of various vitamin deficiency or electrolyte deficiency symptoms may occur, such as vitamin D and calcium absorption disorders may have bone pain, hand and foot spasm, and even pathological fractures; vitamin B family malabsorption may occur glossitis, angular cheilitis, around Neuritis and other; vitamin B12 folic acid and iron malabsorption can cause anemia; potassium ion supplementation can increase the weakness, weakness, physiological oliguria, nocturia and so on.
In addition to the above-mentioned malabsorption manifestations, secondary malabsorption syndrome also has primary disease manifestations.
Examine
Examination of malabsorption syndrome
First, the fecal fat examination
(A) Sudan III staining microscopy: normal fat does not appear in the feces, such as > 10 drops / high power field, indicating abnormal fat absorption.
(B) Quantification of fecal fat: normal <6g 24=""> 6g / 24 hours, can diagnose malabsorption syndrome.
Second, fat balance test
Daily intake of test meals, containing more than 70 grams of fat for 6 consecutive days. The feces were measured for fat content 72 hours after the collection (days 4-6), and the absorption rate was calculated.
Fat absorption rate = fat intake (3 days after) - fecal fat (3 days later) / (fat intake) × 100.
Normal value: >95%, lower than normal indicates fat absorption disorder.
Third, D-xylose absorption test
D-Xylose is a kind of pentose sugar. It is not decomposed by digestive enzymes after oral administration, and is directly absorbed through the jejunal mucosa. It is not metabolized in the body and is excreted from the kidney. If the renal function is normal, measuring the amount of D-xylose excreted in the urine can reflect the absorption function of the small intestine. METHODS: Dose of D-xylose was orally administered on a fasting basis, urine was collected for 5 hours, and D-xylose in urine was measured. Normal value: >1.25g (25%), 1.0~1.2g is suspicious, <1.0g (20%) is abnormal.
Fourth, vitamin B12 absorption test
Reflecting the ileal absorption function, first inject vitamin B121000ug to saturate the body, orally take 60 cobalt labeled vitamin B122ug, collect 48 hours of urine, measure 60 cobalt, normal value: >8-10%, 2-7% is moderate malabsorption, <2% severe malabsorption. It is often used to check the excessive growth of intestinal bacteria.
V. BT-PABA (also known as pancreatic peptide) test
After oral administration of benzoyl-L tyrosine-p-aminobenzoic acid (BT-PABA), it is decomposed in the small intestine by prionase, free para-aminobenzoic acid is easily absorbed by the small intestine, excreted by the kidney, and collected for 6 hours. Its discharge can reflect the exocrine function of the pancreas, the normal value: 55~75%.
Six, barium meal X-ray full gastrointestinal examination
Can understand the secretion and motor function of the small intestine and related diseases, such as intestinal dilatation, stenosis, mucosal fold changes, diverticulum, fistula and so on.
Diagnosis
Diagnosis and identification of malabsorption syndrome
The disease should be identified mainly with tuberculous peritonitis, megacolon and food intolerance.
For patients with long-term diarrhea and weight loss, especially those with fatty sputum, the possibility of malabsorption should be considered. In addition, patients who underwent partial esophagectomy, esophagectomy, total gastrectomy, partial gastrectomy, vagus nerve surgery, small bowel resection, etc., have pancreatic hypofunction, hepatobiliary disease, blind sputum syndrome and Other patients with small bowel lesions requiring surgery may have the presence of malabsorption syndrome.
