申覆理由： Blind loop syndrome, early dumping syndrome及malabsorption皆为Billroth II手术 後之并发症之一, 然而後两并发症之发生率比blind loop syndrome高出许多, 又同时涵 概原本题目中所提及vitamin B12 deficiency, fat malabsorption, abdominal pain, distension症状, 加上blind loop syndrome有其更特异性的诊断法(如下面附件所述),因 此本题应可诊断成两个常见且合理的术後并发症：1. blind loop syndrome, 2. malaborption and early dumping syndrome, 治疗部份, 若是blind loop syndrome则应 该给予抗生素; 但malaborption add early dumping syndrome则给予营养素补充加上症 状治疗,饮食习惯改变为主,则原本之选项无法符合其治疗 申覆资料： 1. Townsend: Sabiston Textbook of Surgery, 18th ed. Chapter 47: Stomach PEPTIC ULCER DISEASE-- Metabolic Disturbances The most common metabolic defect appearing after gastrectomy is anemia. Two types have been identified, and one is related to deficiency in iron and the other to an impairment in vitamin B12 metabolism. Megaloblastic anemia can also occur after gastrectomy, especially when more than 50% of the stomach is removed such as occurs during subtotal gastrectomy. Megaloblastic anemia from vitamin B12 deficiency only rarely develops after partial gastrectomy. Vitamin B12 deficiency occurs secondary to poor absorption of the substance owing to lack of intrinsic factor secretion in the gastric juice. If a patient develops a macrocytic anemia, serum vitamin B12 levels should be obtained. If the vitamin B12 level is abnormal, the patient should be treated with intramuscular injections of cyanocobalamin every 3 to 4 months indefinitely because its administration orally is not a reliable route. Another common metabolic disturbance after gastric resections is impaired absorption of fat. On occasion, steatorrhea may be seen after a Billroth II gastrectomy and may occur as a result of inadequate mixing of bile salts and pancreatic lipase with ingested fat because of the duodenal bypass. If this occurs, a deficiency in uptake of fat-soluble vitamins may also occur. In the setting of steatorrhea, pancreatic replacement enzymes are often effective in decreasing fat loss. Blind Loop Syndrome Blind loop syndrome is a rare condition manifested by diarrhea, steatorrhea, megaloblastic anemia, weight loss, abdominal pain, and deficiencies of the fat-soluble vitamins (A, D, E, and K), as well as neurologic disorders. The underlying cause of this syndrome is bacterial overgrowth in stagnant areas of the small bowel produced by stricture, stenosis, fistulas, or diverticula (e.g., jejunoileal or Meckel's diverticulum). Under normal circumstances, the upper gastrointestinal tract contains fewer than 105 bacteria/mL, mostly gram-positive aerobes and facultative anaerobes. The syndrome can be confirmed by a series of laboratory investigations. Bacterial overgrowth can be diagnosed with cultures obtained through an intestinal tube or by indirect tests such as the 14C-xylose or 14C-cholylglycine breath tests. Excessive bacterial use of 14C substrate leads to an increase in 14CO2. After bacterial overgrowth and steatorrhea are confirmed, a Schilling test (57Co-labeled vitamin B12 absorption) may be performed, which should reveal a pattern of urinary excretion of vitamin B12 resembling that of pernicious anemia (a urinary loss of 0%-6% of vitamin B12 compared with the normal of 7%-25%). In patients with blind loop syndrome, vitamin B12 excretion is not altered by the addition of intrinsic factor, but a course of a broad-spectrum antibiotic (e.g., tetracycline) should return vitamin B12 absorption to normal. 2. Harrison’s pronciples for internal medicine, 17th edition Part 13: disorders of gastrointestinal system, section 1: Dumping Syndrome Dumping syndrome consists of a series of vasomotor and gastrointestinal signs and symptoms and occurs in patients who have undergone vagotomy and drainage (especially Billroth procedures). Two phases of dumping, early and late, can occur. Early dumping takes place 15–30 min after meals and consists of crampy abdominal discomfort, nausea, diarrhea, belching, tachycardia, palpitations, diaphoresis, light-headedness, and, rarely, syncope. These signs and symptoms arise from the rapid emptying of hyperosmolar gastric contents into the small intestine, resulting in a fluid shift into the gut lumen with plasma volume contraction and acute intestinal distention. Release of vasoactive gastrointestinal hormones (vasoactive intestinal polypeptide, neurotensin, motilin) is also theorized to play a role in early dumping. Dietary modification is the cornerstone of therapy for patients with dumping syndrome. Small, multiple (six) meals devoid of simple carbohydrates coupled with elimination of liquids during meals is important. Antidiarrheals and anticholinergic agents are complementary to diet. Maldigestion and Malabsorption Weight loss can be observed in up to 60% of patients after partial gastric resection. A significant component of this weight reduction is due to decreased oral intake. However, mild steatorrhea can also develop. Reasons for maldigestion/malabsorption include decreased gastric acid production, rapid gastric emptying, decreased food dispersion in the stomach, reduced luminal bile concentration, reduced pancreatic secretory response to feeding, and rapid intestinal transit. Decreased serum vitamin B12 levels can be observed after partial gastrectomy. This is usually not due to deficiency of IF, since a minimal amount of parietal cells (source of IF) are removed during antrectomy. Reduced vitamin B12 may be due to competition for the vitamin by bacterial overgrowth or inability to split the vitamin from its protein-bound source due to hypochlorhydria. --

※ 发信站: 批踢踢实业坊(ptt.cc) ◆ From: 61.231.144.95 ※ 编辑: Pardice 来自: 61.231.144.95 (08/05 01:53)