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1、 血液科研究室出科考试题1.急性白血病鉴别常用的组化有哪些?M2、M5 哪些组化阳性? 2.MDS 病态造血骨髓中有哪些改变? 3.白血病及 MDS 常见染色体改变有哪些? 4.ITP 骨髓象特点? 5.缺铁性贫血骨髓象特点?ANEMIA AND GASTRIC SURGERY Gastrectomy, previously used for peptic ulcer and its complications, is the preferred operation for palliation of gastric cancer either as total or partial gast
2、rectomy.Anemia is a frequent complication of gastrectomy.There are many reports addressing iron, vitamin B12 or folate deficiencies either alone or in combination after gastric surgery. The most frequent is the combination of iron and vitamin B12 deficiency40. Impaired absorption of iron following g
3、astrectomy is probably due to operative bypass of the duodenum and to rapid intestinal transit. Reduction in gastric acid (necessary for the absorption of food iron), a common consequence of subtotal gastrectomy, has also been incriminated. Vitamin B12 deficiency develops as a consequence of the dec
4、reased production of intrinsic factor which is essential for vitamin B12 absorption in the lower small bowel, and also because of a defect in the separation of vitamin B12 from its transporter protein. It is a frequent deficiency which will appear 2-4 years or even longer after gastrectomy, when the
5、 vitamin stores are exhausted. Thus, gastrectomized patients should be followed carefully to avoid iron and vitamin B12 deficiencies and anemia. Over the last few decades, bariatric surgery has been suggested as an effective treatment for obesity. There are several different procedures, including ga
6、stric bypass, laparoscopic adjustable gastric banding, vertical banded gastroplasty, biliopancreatic diversion, and biliopancreatic diversion with duodenal switch41. All of these procedures may be associated with long-term sequelae including iron, vitamin B12 and folate deficiencies41,42. ID and ane
7、mia can have a strong impact on quality of life, especially in menstruating women who make up the majority of bariatric surgery patients. Most studies report ID, ranging from 6% to 50% within months to years of followup43- 45. Vitamin B12 deficiency may appear 1-9 years after gastric bypass, and its
8、 prevalence has been estimated to be 12%-33%42. The main causes of ID after bariatric surgery are similar to those described after gastrectomy; diminished gastric acid secretion and exclusion of the duodenum. In gastric bypass, patients experience decreased gastric acid production in their proximal
9、pouch and, in addition, the duodenum is excluded from digestive continuity. Thus,banding procedures which maintain digestive continuity with the antrum and duodenum are associated with low rates of ID and other nutritional deficiencies41.Conversely, the biliopancreatic diversion with duodenal switch
10、, a gastric bypass procedure that may preserve some function of the proximal duodenum, may offer protection from ID, as compared with biliopancreatic diversion (which excludes the duodenum)46,47. Physicians should be aware that folate, vitamin B12,and iron deficiencies occur after gastric bypass, th
11、ough the time to development is variable. In an attempt to prevent nutritional deficiencies, multivitamin preparations are in general prescribed to all patients. Systematic prescription of such supplements may prevent most nutritional deficits. However, vitamin B12 and iron deficits require specific
12、 supplementation. In spite of a multivitamin, ID still develops postoperatively in some patients. Adherence to oral iron supplements is often low because of digestive intolerance, and unresponsive IDA can be an important problem in these patients. Parenteral iron treatment is recommended in those pa
13、tients refractory to oral iron supplementation. Intramuscular vitamin B12 supplementation is recommended only when a deficiency becomes clinically apparent.贫血及胃部手术 胃切除术,用于消化性溃疡及其并发症的治疗,全部或部分胃切除术缓解 胃癌的首选方法。 贫血是胃切除术后较为常见的并发症。有许多报告在胃外科手术后需要治 疗铁,维生素 B12 或叶酸单独或联合缺乏。最常见的是组合是铁和维生素 B12 的联合缺乏40.胃切除后的铁的吸收不良可能
14、是由于十二指肠绕道手术,食物 迅速通过肠道过。胃酸的减少(食物铁的吸收的必要因素)是胃大部切除术的 常见事件。随着内因子产生的减少,出现维生素 B12 缺乏,内因子是维生素 B12 在远端小肠吸收的必需元素,同时,也因维生素 B12 与转运蛋白分离存在 缺陷所致。这种缺乏常见于在胃切除术后 2-4 年或更久时,储存的维生素耗尽。 因此,胃切除术后的患者影密切随访,以避免铁及维生素 B12 缺乏及贫血的发 生。 在过去的几十年中,减肥手术已被建议作为肥胖患者的一种有效治疗手段。 有不同的手术方法,包括胃绕道手术, 腹腔镜垂直束带胃成形术,胆胰分流术, 胆胰及十二指肠球部开关分流术41。所有这些手
15、术方式,都可以引起长期的 后遗症,包括铁, 维生素 B12 和叶酸不足41,42。 铁缺失和贫血可以对生活 质量产生强烈的影响,特别是那些占减肥手术最主要部分的处于育龄期的妇女。 在术后几个月至几年的随访中,大多数研究报告表明会出现铁缺失,概率为 6至 50 43-45。在胃绕道手术 1-9 年后,可能会出现维生素 B12 缺乏, 其患病率据估计达到 12-3342。 减肥手术后发生铁缺失的大部分病例非常相似,胃酸分泌的减少和十二指 肠矿置。在胃绕道手术,患者胃近端袋胃酸的分泌和产生减少,此外,十二指 肠矿置影响了消化道连续性。胃袋成形术,保持胃窦和十二指肠的消化道的连 续性,其发生铁缺失和营
16、养不良的几率较低 41。 相反,相对于胆汁分流术 来讲,胰十二指肠开关分流术及胃旁路手术,可能保存一些近端十二指肠功能, 可以减少铁缺失46,47。 医生应该知道在胃绕道手术后会出现叶酸、维生素 B12、铁缺乏,虽然发 生的时间不同。在预防营养不良,多种维生素制剂适合所有的病人。应用这些 药物行系统的处方治疗可预防大多数营养缺乏。不过,维生素 B12 和铁缺乏, 需要特殊补充。尽管应用多种维生素,在一些术后的患者也会出现铁缺失。坚 持口服补铁往往是效果较差,这是因为其存在消化道不适症状,对于缺铁性贫 血,口服补充治疗效果缓慢,在这些患者是重要问题。在那些口服铁剂治疗后 效果不佳者,应该给予肠外铁剂治疗。当维生素 B12 缺失,引起临床症状是, 应该肌内注射维生素 B12 治疗。