Antimicrobial therapy in patients with impaired renal function

In order to formulate a thoughtful and rational approach to drug dosing in renal failure, the nephrologist must consider several features that influence drug disposition in uremia. Drug bioavailability is generally adversely influenced in patients with renal disease. Drug distribution is frequently altered to an unpredictable degree. Drug protein binding is affected not only by changes in the amount of circulating binding protein but also by the accumulation of endogenous toxins. Renal failure frequently affects drug biotransformation. Drug-dosing tables and nomograms are important; however, they are not a substitute for an encompassing clinical approach and sound clinical judgment.     

造影剂改变肾动脉对内皮素和一氧化氮作用的敏感性

目的　探讨造影剂导致肾血管张力改变的机理及其条件，以及内皮素和一氧化氮（ Ｎ Ｏ） 在其中的作用。方法　采用离体灌流大鼠肾动脉直径测定，观察在不同造影剂、内皮素（ Ｅ Ｔ） 、 Ｎ Ｏ及其它药物的刺激下，肾动脉直径的变化。结果　造影剂能够显著地、特异性地提高大鼠肾动脉对 Ｅ Ｔ缩血管作用的敏感性，此作用主要由 Ｅ Ｔ Ａ 受体介导，与渗透压无关；造影剂能够显著地、特异性地降低大鼠肾动脉对 Ｎ Ｏ 扩张血管作用的敏感性，这一作用主要与渗透压有关。结论　造影剂能特异性地改变大鼠肾动脉对 Ｅ Ｔ及 Ｎ Ｏ 作用的敏感性     

小儿肾脏疾病血,尿内皮素的变化

目的研究小儿肾脏疾病血、尿内皮素（ＰＥＴ、ＵＥＴ）的水平及其相互关系。方法采用同位素放免方法检测了肾病综合征（ＮＳ），肾小球肾炎（ＧＮ），肾功能衰竭（ＲＦ）共７２例患儿血及尿中ＥＴ，血心钠素（ＡＮＰ）水平。结果ＮＳ，ＧＮ，ＲＦ三组的ＰＥＴ及ＵＥＴ值明显高于对照组，尤其ＲＦ组（Ｐ＜００５，Ｐ＜０．０１）。ＡＮＰ值在ＧＮ组和ＲＦ组明显高于对照组（Ｐ＜００１）。８例ＡＲＦ患儿恢复期血ＥＴ水平下降，６例ＣＲＦ患儿虽经治疗，但血ＥＴ水平不降或上升。结论ＥＴ在小儿肾脏疾病发病机理及病情进展中可能起重要作用，其值高低与病情严重程度及预后有关。     

Contrasting renal haemodynamic effects of protein in normal subjects and glomerulonephritic patients with impaired renal function

The effects of a protein load on renal haemo-dynamics in patientswith renal failure are controversial. We measured insulin clearance( C_in and PAH clearance (C_PAH) by constant infusion techniquein six healthy subjects and 13 patients with biopsy-confirmedglomerulonephritis and chronic renal failure. The subjects were pre-equilibrated on their usual diet and studiedbefore and 2 h after 1 g protein/kg as cooked red meat. In healthysubjects this caused a significant increase of C_in (from l36±7.2(SD) to 148±7.9 ml/min/1.73 m²) and of C_PAH (from 547±142to 639±89). In contrast C_in decreased from 72.7±7.7to 60.3±8.4 in patients with chronic renal failure, whereasC_PAH showed no significant change (from 275±67.8 to 278±72.7).A similar decrease of C_in was also seen with acute infusionof amino acids (AA). The change in C_in was not related to changesof PRA or concentrations of plasma amino acids. While absoluteand fractional Na excretion increased in controls, they decreasedin patients in parallel with the decrease of C_in. The decreaseof C_in after infusion of AA was amplified by pre-equilibrationon low-sodium diet (20 mmol Na/day). The effect of meat ingestionon C_in was not obliterated, however, by pretreatment with captopril(25 mg b.i.d. for 7 days). In conclusion, in patients with chronic renal failure, a paradoxicaldecrease in C_in is seen both after oral protein and after amino-acidinfusion.     

妊娠合并急性肾衰竭的临床分析

目的探讨妊娠合并急性肾衰竭ARF）诊治。方法回顾性分析24例妊娠并急性肾衰竭患者的临床资料。结果24例患者中22例患者治愈或好转出院，2例患者死亡。结论早期诊断、积极治疗妊娠合并急性肾衰竭，可以挽救母婴生命。治疗措施包括：适时终止妊娠、早期透析、积极治疗原发病、防治感染。     

急性肾衰竭患者血清胆碱酯酶变化的意义

目的通过观察急性肾衰竭（ARF）患者血清胆碱酯酶（CHE）的变化,探讨血清CHE与ARF预后的关系,并分析其临床意义。方法将68例ARF患者分为存活组（A组）及死亡组（B组）,检测其治疗前后血清CHE,并与40例肾功能正常的原发肾小球疾病患者（M组）和30例健康体检者（N组）比较。结果A组和B组患者血清CHE均较M组和N组降低;而M组与N组间无显著性差异;A组患者治疗后血清CHE恢复,与治疗前CHE相比差异有统计学意义;B组患者治疗后血清CHE持续降低。结论血清CHE可作为ARF的检测物之一,对ARF患者的病情监测和预后判断具有重要的临床意义。     

内皮素与高血压肾损害的关系研究进展

高血压肾损害是指由原发性高血压引起的肾脏结构和功能损害,高血压和肾脏损害两者之间互为因果,相互促进病变发展。内皮素(ET)系统可通过各种机制调控血压及肾脏血流,与高血压肾损害的发生、发展有着密切联系。而内皮素受体拮抗剂(ERAs)则可通过作用于内皮素受体(ETRs),阻断内皮素的效应,从而降低血压,改善肾功能,延缓高血压肾损害的进展。     

Rhabdomyolysis and secondary renal failure in critically ill surgical patients

Background

Rhabdomyolysis accounts for up to 28% of the causes of posttraumatic acute renal failure requiring dialysis. Clinically significant rhabdomyolysis is poorly characterized biochemically and difficult to diagnose.

Methods

A retrospective review of all surgical, trauma, burn, and pediatric surgical patients admitted to Grady Memorial Hospital in Atlanta, GA, from January 1995, through April 2002 was performed. Patients were screened for serum creatinine, base deficit, serum creatine kinase (CK) ≥1,000, presence of myoglobinuria, or if they had a clinical diagnosis of rhabdomyolysis by an attending surgeon.

Results

The sequential addition of admission laboratory values for serum creatinine ≥1.5 mg/dL (positive predictive value [PPV] = 33%), base deficit ≤−4 (PPV = 52%), serum CK level ≥5,000 U/L (PPV = 80%), and myoglobinuria increases the ability to predict which patients will develop dialysis-requiring acute renal failure after an episode of rhabdomyolysis. Patients with maximum CK ≥5,000 are also at increased risk for persistent renal insufficiency (Cr ≥2.0 mg/dL).

Conclusions

An algorithm for testing at-risk surgical patients was developed and may aid in the early diagnosis of clinically significant rhabdomyolysis.     

Renal and systemic effects of continued treatment with renin inhibitor remikiren in hypertensive patients with normal and impaired renal function.

BACKGROUND: Remikiren is an orally active renin inhibitor with established antihypertensive efficacy. As a single dose it induces renal vasodilatation, suggesting specific renal actions. Data on the renal effects of continued treatment by renin inhibition are not available, either in subjects with normal, or in subjects with impaired renal function. METHODS: The effect of 8 days of treatment with remikiren 600 mg o.i.d. on blood pressure, renal haemodynamics, and proteinuria was studied in 14 hypertensive patients with normal or impaired renal function.The study was conducted on an ambulatory in-hospital basis and was designed in a single-blind, longitudinal order. RESULTS: Remikiren induced a significant peak fall in mean arterial pressure of 11.2+/-0.8%, with corresponding trough values of -6+/-0.8%. This fall was somewhat more pronounced in the patients with renal function impairment (-13.3 vs -9.6%; P<0.01). Glomerular filtration rate remained stable, whereas effective renal plasma flow increased from 301+/-35 to 330+/-36 ml/min/1.73 m(2) (P<0.05). Filtration fraction and renal vascular resistance fell by 10+/-2% and 15+/-2% respectively (both P<0.01). Remikiren induced a cumulated sodium loss of -82+/-22 mmol and a positive potassium balance of 49+/-9 mmol (both P<0.01). During remikiren, proteinuria fell by 27% (range -18 to -38%; P<0.01) in the patients with overt proteinuria at onset (n=6). In the remainder of the patients albuminuria fell by 20% (range -1 to -61%, P<0.05). No side-effects were observed. CONCLUSIONS: Continued treatment with remikiren induced a sustained fall in blood pressure, renal vasodilatation, negative sodium balance, and a reduction in glomerular protein leakage. These data are consistent with a renoprotective potential of renin inhibition.     

评价对比剂肾病患者继发终末期肾脏病的风险模型及应用性研究

目的搜集与对比剂肾病(CIN)相关的临床指标,构建评判该患者继发终末期肾脏病(ESRD)的风险性模型,并验证其应用性。方法连续性纳入CIN患者为研究队列,分析研究对象初始入院时的各项临床资料及实验室检查结果,并对其进行为期18个月的随访以确认预后,依据随访结果,进行远期风险性预测和相关危重度评判分析。结果本次研究纳入215例CIN患者,14例失访,19例随访期内进展至ESRD。Cox回归分析显示,近期重复接受造影、高MRS量表评分、高尿肾损伤分子-1(uKIM-1)含量、高尿微量蛋白(umAlb)含量、高尿中性粒细胞明胶酶相关脂质运载蛋白(uNGAL)含量为CIN患者发病18个月内继发ESRD的独立危险因素。以umAlb=36.80ng/ml、uNGAL=128.21ng/ml、uKIM-1=137.56pg/ml为临界值预测CIN患者进展至ESRD的ROC曲线下面积分别为0.746、0.756、0.768。结论本研究建立CIN患者继发ESRD的风险预测模型,并对相关危险因素进行了量化,进一步完善了CIN的诊疗体系。     

Percutaneous nephrolithotomy in patients with normal versus impaired renal function

This study aimed to compare the results of percutaneous nephrolithotomy (PCNL) in patients with impaired renal function (IRF) and normal renal function (NRF). Records of 300 consecutive patients who underwent PCNL from July 2002 to July 2005 were retrospectively reviewed. Nineteen patients (6.3%) had serum creatinine values higher than 1.5 mg/dl before surgery (IRF Group). Nineteen gender and age matched patients with normal renal function were chosen as controls (NRF Group). The surgical parameters, outcome, and complication rates were compared. The effect of PCNL on the renal function was assessed in patients with IRF. There were 13 male and 6 female patients in both groups. In the IRF group, seven patients had a solitary kidney and three had bilateral stones. Thus, PCNL was performed on 22 kidneys. No patients in the NRF Group had solitary kidney or bilateral stones and PCNL was performed on 19 kidneys. There were no statistically significant differences between the two groups for success and complication rates (P = 0.376 and P = 0.184, respectively). In a mean follow-up of 15.6 months, mean serum creatinine decreased from 2.8 to 2.6 mg/dl (P = 0.273) in patients of the IRF group. Similar stone clearance and complication rates were obtained with PCNL in patients with impaired and normal renal function. Surgery does not cause biochemical deterioration in patients with compromised renal function before treatment.     

持续肾替代治疗在肝移植术后急性肾损伤的应用

目的 探讨持续肾替代治疗(CRRT)对肝移植术后急性肾损伤的治疗效果.方法 回顾性分析82例肝移植围手术期应用CRRT患者的肾功能情况,对其治疗前后的主要指标进行检测.结果 与治疗前比较,治疗后患者丙氨酸氨基转移酶(ALT)、总胆红素(TBil)、血尿素氮(BUN)、肌酐(Cr)、肌酸磷酸激酶(CPK)、C反应蛋白(CPR)、肌酐下降,差异均有统计学意义(P＜0.05).与治疗前比较,CRRT治疗后患者血K+、Na+、Cl-、HCO3-、中心静脉压(CVP)显著好转,差异亦具有统计学意义(P＜0.05).其他生化指标与治疗前比较变化不大,差异无统计学意义(P＞0.05).对开始血滤治疗的时机进行研究显示,在急性肾损伤RIFLE分级Ⅰ级开始血滤治疗的患者肾功能恢复的比例明显高于在F级开始血滤治疗的患者(P＜0.05).结论 CRRT治疗能明显改善肝移植术后急性肾损伤患者的预后.     

内皮素和降钙素基因相关肽在急性肾缺血再灌注损伤中的作用

为研究大鼠急性肾缺血再灌注损伤血液和肾组织中内皮素（ＥＴ）和降钙素基因相关肽（ＣＧＲＰ）的动态变化规律，放射免疫法检测急性肾缺血再灌注损伤大鼠血浆和肾皮质、髓质ＥＴ和ＣＧＲＰ水平变化，结果肾组织ＥＴ水平于再灌注３ｈ达到高峰，２４ｈ仍维持较高水平，肾组织ＣＧＲＰ水平再灌注２４ｈ达到高峰，血浆ＥＴ和ＣＧＲＰ于再灌注损伤后虽升高，但无显著性差异，认为肾组织ＥＴ和ＣＧＲＰ升高在急性肾缺血再灌注损伤和修复中     

Acute renal haemodynamic effects of radiocontrast media in patients undergoing left ventricular and coronary angiography.

BACKGROUND: Tubular toxicity and renal ischaemia have been implicated in the pathogenesis of radiocontrast media induced nephropathy (CIN), but their respective role remains unclear. Aims. In order to evaluate changes in renal blood flow in response to intra-arterial contrast media administration, we aimed to continuously measure renal arterial perfusion by means of renal blood flow velocity (RBFV) during left ventricular and coronary angiography and subsequent coronary intervention in patients with chronic kidney disease (CKD). Patients and METHODS: Ten patients (7 males, 63.4 +/- 11.7 years) with serum creatinine (SCr) >1.5 mg/dl participated in the study. The first five patients received low-osmolar iopromide and the others iso-osmolar iodixanol contrast medium. RBFV was measured using a 0.014-inch Doppler guide wire, which was inserted through a separate contralateral femoral sheath via a 5 F Cobra diagnostic catheter into the renal artery. Data were recorded at 500 Hz to allow beat-to-beat analysis of RBFV and pressure. All patients were pre-treated with acetylcysteine and hydration. RESULTS: Immediately after left ventricular angiography no significant changes in RBFV were detected. Over time, however, following repeated administration of the additional contrast medium into the coronary arteries, RBFV decreased significantly from baseline until the end of the investigation, 28.4 (19.1/42.7) to 22.9 (16.9/30.6) cm/s (median and quartiles; P = 0.005), in the absence of significant changes in systemic arterial blood pressure. In individual patients the reduction in RBVF varied from 3.7% to 39.5%. On average the decline in RBFV was more pronounced in patients receiving iopromide (from 41.6 cm/s to 29.3 cm/s) than in those receiving iodixanol (from 19.3 to 17.8 cm/s; P = 0.008 for the difference of relative decline). However, in the iopromide treated patients, coronary intervention was more frequently performed (5/5 versus 2/5) and the median duration of the procedure tended to be longer [85 (32-150) min versus 38 (27-110) min; P > 0.2]. CONCLUSIONS: The administration of non-ionic low-osmolal contrast media has no immediate effect on renal perfusion in patients with CKD. However, during the course of coronary angiography a gradual decline in renal blood flow may occur, the extent of which varies, presumably depending on individual pre-disposition as well as on the amount of the contrast medium.     

前列地尔联合持续性血液净化对急性肾功能衰竭的疗效影响

目的 探讨前列地尔联合连续性血液净化对急性肾功能衰竭患者肾功能的影响.方法 急性肾功能衰竭患者60例,按随机数字表法分为前列地尔组(30例)和对照组(30例),两组均予以连续性血液净化治疗7d,前列地尔组在此基础上联合前列地尔治疗.记录治疗3、7d后患者的血肌酐、血尿素氮,血尿酸、肌酐清除率、尿量、APACHEⅡ评分....     

Predictors of mortality in elderly patients with acute renal failure in a developing country

This prospective study was undertaken to systematically analyze the predictors of mortality in the elderly in a developing country. All elderly patients with ARF hospitalized at this tertiary care centre over 1 year were studied. Various predictors analyzed were hospital-acquired ARF, causative factors of ARF, preexisting hypertension and diabetes mellitus, severity of renal failure (initial and peak serum creatinine, need for dialysis), and complications of ARF: infection during the course of illness; serum albumin levels and critical illness defined as presence of two or more organ system failures excluding renal failure. Of 33,301 patients admitted, 4,255 (12.7%) were elderly. Of these 69 (1.6%) had ARF. On analysis of the whole group, both young and elderly, age >60 years had an independent predictor of mortality (odds ratio 5.6, P = 0.001). Forty-two of the 69 (60.9%) elderly ARF patients died. The mortality was significantly increased in those elderly with hospital-acquired ARF (79.2%, P = 0.027), those with sepsis as a cause of ARF (71.2%, P = 0.004), those who required dialysis (72.5%, P = 0.022), those developing an infection during the course of ARF (87.9%, P = 0.000) and in those with a critical illness (90.0%, P = 0.00). On logistic regression analysis of those variables that were significant on univariate analysis, only critical illness (odds ratio 9.97) and infection during course (odds ratio 9.72) were the independent predictors of mortality. To conclude, ARF complicates only 1.6% of hospitalized elderly patients but is associated with a high mortality rate of 61%. Infection during the course of illness and critical illness were the independent predictors of mortality.     

体外膜肺氧合期间患者发生急性肾功能衰竭的危险因素

目的探寻体外膜肺氧合(extracorporeal membrane oxygenation,ECMO)期间患者发生急性肾功能衰竭(acute renal failure,ARF)的危险因素。方法选择本院2006年1月至2014年12月所有接受ECMO辅助患者170例,男91例,女79例,年龄18~73岁。回顾性分析ECMO辅助患者相关资料,收集患者一般资料,包括性别、年龄;相关疾病史,包括高血压病、糖尿病、心脏病史、ECMO前情况;ECMO辅助期间正性肌力药剂量评分值输血量;机械通气时间、ECMO辅助时间、ICU停留时间;并发症;ECMO前乳酸,ECMO期间C反应蛋白和脑尿钠肽(brain natriuretic peptide,BNP)峰值。将ECMO期间患者按是否发生ARF分为两组,先通过组间单因素分析筛选出影响肾功能的可能危险因素,然后经Logistic回归分析确定ECMO辅助ARF的独立危险因素。结果本研究共纳入研究对象170例,其中发生ARF 91例(53.5%),单因素分析:ECMO前行CPR、ECMO前乳酸水平高、ECMO期间正性肌力药剂量评分值高、大量血制品(红细胞、血浆、血小板)输注、C反应蛋白水平高、BNP水平高、长时间的ECMO辅助是患者发生ARF危险因素。多因素分析表明ECMO前高乳酸水平(OR 2.96,95%CI 1.38~6.34,P=0.005),ECMO期间正性肌力药剂量评分值高(OR 3.17,95%CI1.52~6.61,P=0.002)是ECMO辅助患者发生ARF的独立危险因素。结论 ECMO期间患者ARF发生率高,ECMO期间大剂量正性肌力药的应用,ECMO前高乳酸水平是ARF的危险因素。     

双侧上尿路结石梗阻并发急性肾功能衰竭(附40例报告)

目的：探讨双侧上尿路结石梗阻并发急性肾功能衰竭的诊断及治疗方法。方法：通过Ｂ超、ＫＵＢ、逆行插管造影检查明确诊断并通过肾、输尿管切开取石，肾穿刺造瘘，输尿管插管引流，ＥＳＷＬ达到治疗目的。结果：术后全部患者尿毒症症状减轻或消失，血尿素氮（ＢＵＮ）、血肌酐（Ｃｒ）均不同程度降低或恢复正常。结论：对双侧上尿路结石宜争取同期施行双侧手术，因并发严重感染或患者一般情况差而无法取石者则应及早作输尿管逆行插管     

Acute renal failure after exercise in a child with renal hypouricaemia

We describe a 12-year-old boy with renal hypouricaemia who presented with acute renal failure after a 6-h sports training session. Back and loin pain were noted at presentation. Although serum creatinine and blood urea nitrogen were elevated, the serum uric acid concentration was normal (2.6 mg/dl). This decreased to 0.3 mg/dl after recovery. The pyrazinamide and probenecid tests revealed that the cause of renal hypouricaemia in this patient was totally defective uric acid reabsorption. Acute renal failure after exercise is a rare but serious complication in paediatric patients with renal hypouricaemia.