Malabsorption syndrome of the small intestine

　　It is a clinical syndrome caused by the impairment of the digestion and absorption function of the small intestine due to various reasons, resulting in the normal absorption of nutrients not being possible and being excreted through feces, leading to nutritional deficiency. Various causes include the impairment of the digestion and absorption function of the small intestine due to intestinal tumors and other diseases, resulting in the normal absorption of nutrients not being possible and being excreted through feces, leading to nutritional deficiency.

　　1. Insufficient small intestinal absorption area such as excessive small intestinal resection (short bowel syndrome), gastrocolonic fistula, inappropriate gastrointestinal anastomosis, jejuno-colonic fistula, etc.

　　2. Small intestinal mucosal lesions such as small intestinal inflammation, including infectious, radioactive, drug-induced (neomycin colchicine, etc.); parasitic diseases, such as giardiasis, nematodiasis, etc.

　　3. Intestinal wall infiltrative lesions such as lymphoma, tuberculosis, Crohn's disease, Whipple's disease, etc.

　　4. Small intestinal motility disorders such as hyperkinetic thyroid function, which affects the absorption time of the small intestine, and hypokinetic disorders such as pseudo-obstruction of the small intestine, systemic sclerosis, leading to excessive growth of small intestinal bacteria.

　　5. Lymphatic flow disorders such as lymph hypoplasia, lymphatic obstruction (trauma, tumor, tuberculosis, etc.), and circulatory disorders (portal hypertension, congestive heart failure).

　　1. Medical history and symptoms

　　The number of diarrhea, duration, appearance and amount of feces, 80%-97% of patients have diarrhea, which is typically steatorrhea, with light feces color, large amount, greasy or foamy, often with a bad smell. The number of bowel movements ranges from several to more than ten, and sometimes presents intermittent diarrhea, abdominal pain, and abdominal distension is rare. It is also necessary to inquire about the presence of symptoms such as weight loss, fatigue, cramps in the hands and feet, abnormal sensation, stomatitis, corneal dryness, night blindness, edema, and other symptoms of malnutrition. Past examination and treatment also help in diagnosis.

　　2. Physical examination findings

　　Patients may have symptoms such as weight loss, mild abdominal tenderness, abnormal sensation in the distal extremities, stomatitis or ulcer, hyperpigmentation like pellagra, edema, concave nails, muscle tenderness, clubbing (toes), etc.

　　1. It is best to adopt a high-calorie, high-protein, high-vitamin, easy-to-digest, non-irritating low-fat diet.

　　2. Malabsorption syndrome is more common in the elderly, mainly related to the degenerative changes of the elderly digestive system. After entering the elderly period, the villi of the small intestine become shorter, the absorption area decreases, and the pancreas gradually atrophies, which can promote or worsen malabsorption syndrome.

　　3. Physical labor should be limited, and it is not advisable to live in a hot environment.

　　Most have macrocytic anemia, serum electrolytes, plasma albumin, cholesterol, and even folic acid, vitamin B12 levels are low, fecal fat quantification > 6g/d, dextrose absorption test

　　For patients with poor digestion and absorption, due to symptoms such as diarrhea, abdominal pain, weight loss, anemia, and systemic malnutrition, dietary adjustment plays a very important role in improving the above symptoms and promoting the recovery of the patient.
　　(1) Provide sufficient heat energy and protein. Due to the long-term chronic course, the body consumes a lot, and sufficient heat energy should be provided to prevent further weight loss. High-protein, high-calorie, low-fat semi-liquid or soft food can be provided, with more than 100 grams of protein per day, 40 grams of fat per day, and a total of 10460 megajoules (2500 kcal) per day of heat energy. Choose foods with low fat content and easy digestion. For severe cases, intravenous hyperalimentation or elemental diet and slurry diet can be adopted to ensure heat energy and positive nitrogen balance.
　　(2) Supplement sufficient vitamins. In addition to food supplementation, vitamin preparations can be given if necessary. Based on clinical symptoms, focus on supplementing the corresponding vitamins, such as vitamin A, vitamin B complex, vitamin C, vitamin D, vitamin K, etc.
　　(3) Pay attention to electrolyte balance. The supplementation of electrolytes is extremely important in severe diarrhea, and early intravenous supplementation can be used. Fresh fruit juice, oil-free meat soup, mushroom soup, etc., should be given in the diet. Iron-deficiency anemia patients can eat iron-rich foods such as animal liver, and iron preparations can be taken orally if necessary.
　　(4) Small and frequent meals. Choose fine, soft, easily digestible foods, which can ensure sufficient nutrition without increasing the burden on the intestines. In cooking, try to make the food fine, broken, and soft, and prefer to use methods such as boiling, braising, stewing, and steaming, avoiding methods such as frying, deep-frying, and stir-frying to reduce the amount of fat supplied. Attention should be paid to the color, smell, taste, and shape of the food, and every effort should be made to increase the appetite of the patient. It is advisable to have 6 to 7 meals a day.
　　(5) To ensure nutritional supply, substitute therapy can be used for patients with decreased appetite. Oral essential nutrients, complete nutrition preparations, etc., can be used to supplement nutrition.

　　Substitution therapy is an important measure for the treatment of such diseases. The best choice is intravenous hyperalimentation to supplement lost electrolytes and various nutrients and vitamins. In necessary cases, white blood cells or blood transfusion may be administered intravenously. There are also some special measures for specific causes.

　　1. Celiac disease

　　Zinc sulfate 200mg, oral, 3 times daily; vitamin K4, 8mg, IM once daily; 10% calcium gluconate 10ml, IV. In severe cases, hydrocortisone infusion or prednisone oral treatment may be applied.

　　2. Tropical inflammatory diarrhea

　　Tetracycline 250-500mg, 4 times daily, for one month, then changed to 2 times daily for half a year maintenance.

　　3. Whipple's disease

　　Procaine penicillin G 1.2 million μg + streptomycin 1.0g, IM, once daily, for a total of two weeks, changed to tetracycline 0.5g, oral, 4 times daily, maintained for several months.