Long-term Iron Needs of Renal Transplant Recipients

描述(由申请人提供)：该项目的长期目标是：(A)针对肾移植受者(RTxRs)的需要制定口服铁/抗坏血酸补充剂，(B)评估作为移植后(TX后)常规护理的一部分，口服铁/抗坏血酸补充剂满足这一患者群体铁需求的有效性，以及(C)建立与移植/肾脏病中心合作的咨询服务。许多RTxR有患缺铁性贫血的风险。大多数是因为他们有绝对缺铁(AID)，尽管有些人有相对缺铁(RID)。目前尚不存在识别和治疗移植后贫血(PTA)的有效策略，其发展需要深入了解影响RTXR中铁吸收和利用的因素。我们最近开发了一种非侵入性方法，可以评估铁吸收/利用的效果。我们的方法是基于口服已知数量的稳定同位素标记铁(58Fe)和不可吸收的标记DyCl3，然后在实验室分析一到两个粪便样本的58Fe-过量/Dy和两周后获得的血液样本的58Fe-过量。我们建议调查影响RTXR铁状态的因素，以及作为长期护理的一部分，如何为他们的红细胞生成需求提供铁。在第一阶段，我们将确定我们满足RTxRs铁需求的总体战略的可行性，方法是证明AID患者在整个TX后期间从低剂量抗坏血酸亚铁中吸收/利用足够高的铁，从而允许将其用于此目的。在IE阶段，我们将研究铁补充剂的参数-剂量、频率、铁和抗坏血酸的最有效配方-这些参数对于制定有效的策略和与免疫抑制治疗等问题有关的重要因素。

DESCRIPTION (provided by applicant): The long-term objectives of this project are to: (a) Formulate an oral iron/ascorbic acid supplement specific to the needs of renal transplant recipients (RTxRs), (b) evaluate the efficacy of oral iron/ascorbic acid supplementation to meet the iron needs of this patient population as part of their routine post-transplant (post-Tx) care, and (c) establish a consulting service to work in collaboration with transplant/nephrology centers. Many RTxRs are at risk for iron-deficiency anemia. Most because they have absolute iron deficiency (AID) although some have relative iron deficiency (RID). An effective strategy to identify and treat post-transplant anemia (PTA) currently does not exist and its development necessitates insight into factors that affect iron absorption and utilization in RTxRs. We have recently developed a noninvasive method that permits evaluation of the efficacy of iron absorption/utilization. Our method is based on oral administration of a known amount of stable-isotope-labeled iron (58Fe), and the nonabsorbable marker DyCl3, followed by laboratory analysis of the ratio 58Fe -Excess/Dy in one or two stool samples and 58Fe -Excess in a blood sample obtained two weeks later. We propose to investigate factors that affect iron status of RTxRs and how to provide iron for their erythropoietic needs as part of their long-term care. During Phase-I, we will establish the feasibility of our overall strategy for meeting the iron needs of RTxRs by demonstrating that absorption/utilization of iron from low-dose ferrous ascorbate is sufficiently high throughout the post-Tx period in patients with AID to permit its use for this purpose. During Phase- IE, we will investigate parameters of iron supplementation-dose, frequency, most effective formulation of iron plus ascorbate - that are important for development of an effective strategy and in relation to issues such as immunosuppressive therapy.