The effects of vitamin D receptor polymorphism on secondary hyperparathyroidism and bone density after renal transplantation.

Immunosuppresive treatment and secondary hyperparathyroidism (SHPT) are considered among the most important pathogenetic factors for postrenal transplant bone disease. The aim of this study was to investigate the relationships among vitamin D receptor (VDR) gene polymorphism, parathyroid hormone (PTH) levels, and bone density in renal transplant recipients. We enrolled 69 patients (47 men and 22 women; mean age, 47 +/- 11 years) who had undergone kidney transplantation 51 +/- 5 months before. All patients underwent an evaluation of the main biochemical parameters of bone metabolism as well as bone densitometry. VDR alleles were typed by a polymerase chain reaction (PCR) assay based on a polymorphic BsmI restriction site. When the patients were categorized according to the VDR genotype (BB, Bb, and bb), serum creatinine, and the cumulative doses of immunosuppressive drugs were similar across the groups. PTH levels higher than 80 pg/ml were found in 53.6% of the patients, with the highest values being detected in the bb VDR genotype (p < 0.05). PTH was significantly correlated to urinary type I collagen cross-linked N-telopeptide (NTx) values. Bone density was low in the whole population; however, spinal bone density was lower in the bb subgroup (p < 0.02). In the whole population, only PTH (p < 0.05) and body mass index (BMI; p < 0.01) were independent predictors of spinal bone density. When grouping the patients by the VDR gene polymorphism, only PTH continued to be an independent predictor of spinal bone density in the bb allele subgroup (R2 adj. = 0.17). We can conclude that the VDR genotype polymorphism affects bone density of renal transplant recipients via its effects on the severity of SHPT.     

Improved renal allograft survival with vitamin D receptor polymorphism

BACKGROUND: Polymorphisms in genes, coding for proteins involved in immune response, or the pathogenesis of atherosclerosis may influence immunological and non-immunological mechanisms that lead to allograft loss. Vitamin D receptor (VDR) agonists reduce allograft rejection in animal models, and there are a number of functional polymorphisms in VDR. METHODS: In all, 379 renal transplant recipients were genotyped for VDR (FokI & ApaI) polymorphisms, and the association of each genotype with renal allograft survival and acute rejection was determined. RESULTS: There was significantly improved allograft survival for patients who were homozygous or heterozygous for the VDR FokI T allele (Hazard Ratio [HR] = 0.488, p < 0.001). CONCLUSION: The association of VDR FokI T allele with improved renal allograft survival is a unique observation. The finding is in keeping with data showing the prevention of chronic allograft rejection with the use of Vitamin D receptor agonists.     

Risk factors for cardiovascular disease after renal transplantation

Cardiovascular diseases (CVD) have become the leading cause of mortality in renal transplant recipients. Well-known cardiovascular (CV) risk factors and graft dysfunction both play an important role in the development of the posttransplantation CV events. We studied 233 stable kidney transplant patients to establish the prevalence of CVD and to assess CV risk factors that can be evaluated (and modified) in daily clinical practice. While 6.2% of the patients had coronary heart disease (CHD) before the transplantation, 16% displayed at least 1 CV event posttransplantation. The most significant factors associated with CV events were as follows: gender, length of smoking, diabetes mellitus, hepatitis C virus antibodies (HCV), dyslipidemia, proteinuria, and serum creatinine levels.     

Risk factors for cardiovascular events after successful renal transplantation

BACKGROUND: Cardiovascular disease is a frequent cause of morbidity after renal transplantation. The aims of this study were to evaluate the incidence of cardiovascular events and to identify the main risk factors for cardiovascular complications and mortality in 2071 white adults with a renal transplant functioning for at least 1 year. METHODS: Clinical events, routine biochemistry, and prescribed drugs at month 1, month 6, and yearly after transplantation were analyzed. RESULTS: The incidence of cardiovascular events increased over time. At 15 years after transplantation, only 47% of surviving patients had not experienced any cardiovascular event. Risk factors associated with cardiovascular complications were male gender (P=0.04), age (P<0.0001), arterial hypertension before transplantation (P<0.0001), longer pretransplant dialysis (P<0.0001), cardiovascular event before transplantation (P<0.0001), older era of transplantation (P=0.0009), center-specific effect (P=0.003), posttransplant diabetes mellitus (P=0.01), increased pulse pressure after transplantation (P=0.02), intake of corticosteroids (P=0.016), intake of azathioprine (P=0.016), lower serum albumin after transplantation (P=0.004), and higher serum triglyceride levels after transplantation (P=0.007). The risk of death was increased in patients with low or elevated hematocrit, while it was minimal with values around 38%. CONCLUSIONS: The occurrence of fatal and nonfatal cardiovascular events after successful renal transplantation not only relates to baseline cardiovascular risk factors present at transplantation, but also to immunosuppressive drugs and posttransplantation traditional and nontraditional risk factors.     

肝移植术后慢性肾功能损伤的危险因素分析

目的 探讨影响肝移植术后慢性肾功能损伤(CRD)的危险因素.方法 回顾性分析2007年1月至2008年1月于中国人民武装警察部队总医院接受肝移植术后生存时间＞3年的101例患者的临床资料,应用MDRD公式计算术前以及术后1、3年的肾小球滤过率(GFR).根据术后GFR是否＜60 ml/min将患者分为CRD组(16例)和对照组(85例).采用x2检验或t检验对可能影响肝移植术后肾功能的16项危险因素(性别、年龄、高血压、糖尿病、肌酐、尿素氮、他克莫司浓度、术前GFR、热缺血时间、冷缺血时间、国际标准化比值、TP、TBil、ALT、AST、ALP)进行单因素分析,将差异有统计学意义的因素进行Logistic多因素回归分析.结果 101例肝移植患者手术前GFR为(103±22) ml/min,其中3例患者术前GFR＜60 ml/min;101例患者肝移植术后l、3年GFR分别为(91 ±22) ml/min和(83 ± 21) ml/min,其中7例患者肝移植术后1年GFR＜ 60 ml/min,16例患者术后3年GFR＜ 60 ml/min.单因素分析结果表明:高血压、糖尿病、肌酐、尿素氮、他克莫司浓度和术前GFR是肝移植术后CRD的危险因素(x2=9.400,21.917,f =51.024,91.620,41.381,99.000,P＜0.05).多因素分析结果表明:高血压、糖尿病和术前GFR是肝移植术后CRD的独立危险因素(OR=65.438,17.903,0.911,P＜0.05).结论 GFR降低和手术前合并高血糖和高血压是肝移植术后CRD的危险因素.     

肾移植术后巨细胞病毒肺炎的危险因素

分析肾移植术后巨细胞病毒（CMV）肺炎的发病和死亡危险因素．采取有效的防治措施，有利于减少术后CMV肺炎的发病和改善疾病预后。分析肾移植术后巨细胞病毒（CMV）肺炎的发病和死亡危险因素．采取有效的防治措施，有利于减少术后CMV肺炎的发病和改善疾病预后。     

Risk factors of arterial hypertension after renal transplantation

Arterial hypertension often present after kidney transplantation is of multifactorial origin. The aim of this study was to determine the role of donor and recipient factors in the development of hypertension after renal transplantation. We retrospectively analyzed the data of 280 patients transplanted between 1985 and 2005, who still had functioning grafts at 1 year after transplantation. We recorded donor and recipient parameters. One hundred eighty-seven patients (66.8%) were hypertensive. Upon multivariate analysis of recipient factors, pretransplant hypertension (odds ratio) [OR]: 8.5, 95% confidence interval [CI]: 4.5 to 16.1); serum creatinine level > 130 micromol/L at 6 months (OR: 2.5, 95% CI: 1.3 to 4,7), male gender (OR: 2.02, 95% CI: 1.2 to 3.4), and chronic rejection (OR: 2.4, 95% CI: 1.2 to 4.7) were independent predisposing factors. Among donor factors, age was significantly associated with arterial hypertension upon univariate analysis. In conclusion, recipient factors, especially pretransplant hypertension, contribute to the disorder in renal transplant patients.     

肾移植术后早期移植肾失功的危险因素分析

目的探讨肾移植术后发生早期移植肾失功的危险因素。方法回顾性分析35例肾移植术后2个月内发生移植肾失功患者（失功组）和同期70例未发生移植肾失功患者（对照组）的临床资料,应用单因素分析和多因素逐步Logistic回归分析找出导致早期移植肾失功的危险因素和独立危险因素,得出回归方程,并计算该模型判断有危险因素病例的早期移植肾失功的准确率。结果单因素分析表明,两组间供肾的热缺血时间、冷缺血时间、供肾血管异常、受者术前群体反应性抗体（panel reactive antibody,PRA）水平、供受者之间人类白细胞抗原（human leucocyte antigen,HLA）位点错配数是影响肾移植术后早期移植肾失功的危险因素（P〈0.05-0.01）。多因素逐步Logistic回归结果提示供受者之间HLA位点错配数、受者术前PRA水平、供肾冷缺血时间是早期移植肾失功的独立危险因素,其优势比分别为7.823、5.389和1.259（P〈0.05-0.01）。由此得出回归方程为：Y=-8.544＋2.057X1＋1.684X2＋0.230X3,该模型对具有危险因素的病例发生早期移植肾失功的预测准确率为80%。结论供受者之间HLA位点错配数、受者术前PRA水平、供肾冷缺血时间是肾移植术后早期移植肾失功的高危因素。     

北方汉族人群维生素D受体基因Bsm I位点多态性与前列腺癌易感性的相关性分析

目的 :研究低发病的中国汉族人群维生素D受体基因 (VDRG)BsmⅠ 位点单核苷酸多态性 (SNP)与前列腺癌的关系 ,探讨不同种族前列腺癌发病的基因差异。　方法 :收集中国北方地区汉族人群 10 3例前列腺癌病人及10 6例健康对照者外周血标本 ,应用变性高效液相色谱 (DHPLC)检测VDRG第 8内含子BsmⅠ多态位点 ,并对该位点SNP分布进行分析。　结果 :BsmⅠ 多态位点bb、Bb、BB基因型和等位基因在北方地区汉族前列腺癌病人及对照者中的分布频率差异无显著性 (P >0 .0 5 ) ,基因型分布频率分别为 92 .2 3%、7.77%、0和 94.34 %、5 .6 6 %、0 ;等位基因B、b分别为 3.88%、96 .12 %和 2 .91%、97.0 9%,而与高发病人群的分布相比有显著不同。　结论 :VDRGBsmⅠ多态性在低发病的中国汉族人群与前列腺癌无相关 ,其分布与高发病人群有明显差异 ,提示VDRGBsmⅠ多态性可能是前列腺癌发病种族差异的原因之一。     

Risk factors for development of acute renal failure after liver transplantation

BACKGROUND: Acute renal failure (ARF) is a common complication after liver transplantation (LTx). Identification of risk factors may prevent the development and attenuate the impact of ARF on patients outcome after LTX. METHODS: Retrospective analysis of variables in the pre, intra, and postoperative periods of 92 patients submitted to LTx was performed in order to identify risk factors for development of ARF after LTx. ARF was defined as serum creatinine > or = 2.0 mg/dL in the first 30 days after LTx. Univariate and multivariate analysis by logistic regression were performed. RESULTS: ARF group comprised 56 patients (61%). Preoperative serum creatinine was higher in ARF group. During the intraoperative period, ARF group required more blood transfusions, developed more episodes of hypotension and presented longer anesthesia time. In the postoperative period, ARF group presented higher serum bilirubin and more episodes of hypotension. Dialysis was required in 10 patients (11%). The identifled risk factors for development of ARF were: preoperative serum creatinine > 1.0 mg/dL. more than five blood transfusions in the intraoperative period, hypotension during intra and postoperative periods. The identified mortality risk factors were hypotension in the postoperative period and no recovery of renal function after 30 days. CONCLUSIONS: Several factors are involved in the pathogenesis of ARF after LTx and may influence patients outcome and mortality. Pretransplant renal function and hemodynamic conditions in the operative and postoperative periods were identified as risk factors for development of ARF after LTx. Nonrenal function recovery and postoperative hypotension were identified as mortality risk factors after LTx.     

Risk factors of acute renal failure after liver transplantation

The objective of this study was to determine the risk factors of postoperative acute renal failure (ARF) in orthotopic liver transplantation (OLT). We reviewed 184 consecutive OLT. Postoperative ARF was defined as a persistent rise of 50% increase or more of the S-creatinine (S-Cr). The patients were classified as early postoperative ARF (E-ARF) (first week) and late postoperative ARF (L-ARF) (second to fourth week). Preoperative variables were age, sex, comorbidity, indication for OLT, Child-Pugh stage, united network for organ sharing status, analysis of the blood and urine, and donor's data. Intraoperative variables were systolic arterial pressure, mean arterial pressure, pulmonary capillary wedge pressure, cardiac index, and systemic vascular resistance index. Surgical technique, number of blood products transfused, need for adrenergic agonist drugs, and intraoperative complications were also important. Postoperative variables were duration of stay in the intensive care unit, time on mechanic ventilation, liver graft dysfunction, need for adrenergic agonist drugs, units of blood products infused, episodes of acute rejection, re-operations, and bacterial infections. Firstly we carried out a univariate statistical analysis, and secondly a logistic regression analysis. The risk factors for E-ARF were: pretransplant ARF (odds ratio (OR)=10.2, P=0.025), S-albumin (OR=0.3, P=0.001), duration of treatment with dopamine (OR=1.6, P=0.001), and grade II-IV dysfunction of the liver graft (OR=5.6, P=0.002). The risk factors for L-ARF were: re-operation (OR=3.1, P=0.013) and bacterial infection (OR=2.9, P=0.017). The development of E-ARF is influenced by preoperative factors such as ARF and hypoalbuminemia, as well as postoperative factors such as liver dysfunction and prolonged treatment with dopamine. The predicting factors of L-ARF differ from E-ARF and correspond to postoperative causes such as bacterial infection and surgical re-operation.     

维生素D受体基因Apa I多态性与骨质疏松症相关性的研究

目的研究维生素D受体（vitamin Dreceptor,VDR）基因ApaⅠ多态性与原发性骨质疏松症的相关性。方法应用聚合酶链反应-限制性片段长度多态性分析技术测定山东半岛地区155例骨质疏松患者和113例对照者维生素D受体基因ApaⅠ多态性,比较两组基因型和等位基因分布频率。结果两组基因型和等位基因差异有显著性（P〈0.05）。男性及〈65岁骨质疏松组同相应对照组相比差异无显著性,女性及≥65岁骨质疏松组同相应对照组相比差异有显著性（P〈0.05）;≥65岁女性骨质疏松组aa基因型与a等位基因频率高于其对照组。结论山东半岛地区汉族人群中,维生素D受体基因ApaⅠ多态性与原发性骨质疏松症存在相关性,65岁及以上女性a等位基因是易感基因,aa基因型个体存在易感性。     

Risk factors for hypertension 3 years after renal transplantation in children

We performed a case-control study in renal transplant patients between 1998 and 2003 to identify risk factors for arterial hypertension over the medium term in pediatric patients undergoing renal transplantation. Three years after transplant, patients were classified into hypertensive or control groups. The following risk factors were analyzed: hypertension before transplant, glomerular filtration rate at sixth posttransplant month, acute rejection episodes, renal artery stenosis, accumulated prednisone and calcineurin inhibitor doses, presence of native kidneys, donor type (living or cadaver), body mass index at 1 year posttransplant, and glomerular disease as renal insufficiency etiology. Of 161 transplants, 124 fulfilled the inclusion criteria; 63 were hypertensive, and 61 were controls. Univariate analysis showed hypertension before transplant (52/63 vs. 27/61, p < 0.001), glomerulopathies (23/63 vs. 12/61, p = 0.001), glomerular filtration rate at 6 months (71 +/- 18 vs, 80 +/- 18 ml/min per 1.73 m(2), p = 0.003) as risk factors. A tendency to statistical significance was observed with regard to body mass index (SDS) in the first year (0.40 +/- 1.10 vs, 0.04 +/- 1.10, p = 0.072). Multivariate analysis showed statistical significance concerning previous hypertension and glomerular filtration rate at 6 months. Hypertension before transplant and early graft function are the major risk factors for hypertension in the medium term following renal transplant.     

Risk factors for changes in bone mineral density and the effect of antiosteoporosis management after renal transplantation

Using the pretransplant bone mineral density (BMD) data records of renal recipients, we retrospectively examined risk factors affecting posttransplant changes in BMD and the effect of antiosteoporosis management. For 294 kidney transplant recipients from January 1996 to September 2003, BMD values were expressed as spine and femur T-scores. Gender, age, pretransplant diabetes, blood type compatibility, mode and duration of dialysis, and previous transplantation were considered to be variables affecting BMD changes. T-test or ANOVA was used to compare risk factors. At the time of transplantation, mean spine T-scores were significantly lower among the retransplant group. Mean femur T-scores were significantly lower among the retransplant group, older patients (older than 45 years), and female recipients. Prolonged hemodialysis (>12 months) and retransplant were risk factors for BMD loss during the first year posttransplant. Early application of antiosteoporosis management was effective to ameliorate posttransplant BMD loss. However, antiosteoporosis management after 1 year posttransplant was relatively ineffective. Pretransplant evaluation of BMD and the possibility of significant BMD loss during the first posttransplant year should not be overlooked. Prophylaxis against bone loss and treatment should be started as soon as possible after transplantation for recipients with either normal or abnormal pretransplant BMD.     

Pretransplant serum vitamin D levels and risk of cancer after renal transplantation

BACKGROUND: Serum levels of 25-OH-D3 inversely correlate with the incidence of various types of cancers in the general population. Because risk factors and incidence of cancer in renal transplant recipients (RTRs) are different from the general population, this study was designed to determine whether pretransplant 25-OH-D3 levels could be predictive of cancer risk in RTRs. METHODS: Pretransplant 25-OH-D3 levels were reviewed in 363 consecutive RTRs. The impact of 25-OH-D3 levels on the development of cancer was then analyzed with respect to other known risk factors. RESULTS: One hundred twenty-four patients (34.2%) showed vitamin D deficiency, 185 (51%) vitamin D insufficiency, and 54 (14.8%) with normal vitamin D levels. Thirty-two cancers (8.8%) occurred in 32 patients. A higher incidence of cancer was observed in patients with vitamin D deficiency (13.7% vs. 7% for patients with vitamin D insufficiency [P=0.068] and 3.7% for those with normal vitamin D levels [P=0.007]). 25-OH-D3 levels were lower in patients who developed cancer after transplantation (13.7+/-6 vs. 18.3+/-17.8 ng/mL, P=0.022). Age (hazard ratio, 1.06; 95% confidence interval, 1.02-1.11, for each 1 year increase; P=0.009) and low 25-OH-D3 levels (hazard ratio, 1.12; 95% confidence interval, 1.04-1.23, for every 1 ng/mL decrease; P=0.021) were independent risk factors for development of cancer. CONCLUSION: Pretransplant level of 25-OH-D3 is an important determinant for subsequent development of cancer after transplantation. Future studies should examine whether 25-OH-D3 supplementation can effectively decrease the incidence of cancer in RTRs.     

Risk factors for nontraumatic osteonecrosis of the femoral head after renal transplantation

We investigated risk factors for osteonecrosis of the femoral head (ONF) in renal transplant recipients, who are susceptible to the disease. Among 287 renal transplant recipients, 18 ONF patients with enough data were included, and 18 age- and sex-matched recipients without ONF were nominated as reference cases. Risk factors were analyzed using a conditional logistic regression method. There were no differences between the ONF patients and the reference cases regarding the types of immunosuppressant or the donor (living or cadaveric, father or mother, matching blood type and human leukocyte antigens). The daily oral steroid dosage (prednisolone 25.0mg/day or more) and blood urea nitrogen level 2 months after transplantation were the only factors with relevance to the occurrence of ONF. We propose that oral steroid dosages should be low or reduced after renal transplantation, and acute rejection should be controlled with pulsed therapy.