The Practicality & Utility of Estimated vs Measured Renal Function in Advanced Kidney Disease, Whether Treated With Dialysis or Not: Can Better Techniques be Used to Predict the Onset of the Uraemic Syndrome and Guide Dialysis Requirements
试验速览
- 阶段
- 不适用
- 状态
- 尚未招募
- 入组人数
- 150
- 试验地点
- 1
- 主要终点
- Iohexol measured glomerular filtration rate
研究概览
简要总结
The goal of this observational study is to assess if new ways of measuring kidney function can better predict when individuals will become symptomatic due to kidney failure, and whether residual kidney function can be accurately measured in those already on dialysis.
The main questions the study is trying to answer is whether measuring kidney function by clearance of iohexol is comparable to the current standard of care methods.
In addition to routine care, participants will:
- undergo a brief clinical assessment
- be given an injection of iohexol and asked to perform 4 finger prick blood tests over 24 hours, recording the time of each sample. Samples will be returned in person or posted back
- be asked to complete a questionnaire on their experience
详细描述
The eligible study population includes all adults under the care of nephrology at Manchester Foundation Trust with advanced chronic kidney disease approaching end stage renal failure and those established on haemodialysis who still produce urine. This pilot study aims to collect 50 measurements in each of three groups of participants (total 150): (1) those with advanced kidney disease not yet on dialysis; (2) those undergoing peritoneal dialysis and (3) those undergoing haemodialysis who still have residual kidney function. Those who have not yet started dialysis will have repeat measurements when they become symptomatic with renal failure and a third time after they are established on dialysis (either peritoneal or haemo-) to assess for a threshold of renal function at which individuals need to start dialysis, and consistency of the measurements whether undergoing dialysis or not. This will mean a maximum of 150 participants would be required.
Screening and recruitment will take place in advanced kidney care clinics, peritoneal dialysis clinics and dialysis units managed by Manchester University NHS Foundation Trust. Potential participants will be given information about the study by their usual care provided and, if agreeable, contacted later by the research team for further discussion and formal recruitment to the study.
Study methods:
======== Participants will have up to three sets of tests taken as part of the study depending at what stage they are recruited.
Each set of tests is done over one planned visit to hospital, except for those on haemodialysis where samples are taken from two consecutive visits. All study visits coincide with routine care with no study specific hospital visits.
研究设计
- 研究类型
- Observational
- 观察模型
- Cohort
- 时间视角
- Cross Sectional
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Adults (18 year s or older)
- •Able to give informed consent
- •Progressive chronic kidney disease predicted to start renal replacement therapy in the next 6 months OR established on dialysis (either haemodialysis or peritoneal) with residual renal function (Urine output >100ml/day)
排除标准
- •Under 18 years
- •Known allergy to iodinated contrast media
- •Unable to perform fingerprick blood testing
- •Unable to comply with urine collection
- •Unable or unwilling to give informed consent in English
- •Acute kidney injury expected to recover renal function
- •Pre-dialysis and planned renal transplant within 1 month
- •Pregnant or breast feeding
- •Significant fluid overload (significant peripheral oedema or ascites AND >10kg above estimated dry weight)
研究组 & 干预措施
Advanced Chronic Kindney Disease expected to need dialysis in the next 6 months
As per study description: individuals with progressive advanced chronic kidney disease. Interventions of interest include iohexol injection and 4x finger prick sample collection; clinical review; questionnaire. Routine blood and urine tests are also of interest.
干预措施: Iohexol Inj 300 MG/ML Diagnostic aid/agent used to measure glomerular filtration rate (GFR) (Diagnostic Test)
End stage kidney disease established on peritoneal dialysis with >100ml / 24hours urine output
As per study description: individuals with established end stage chronic kidney disease undergoing peritoneal dialysis. Interventions of interest include iohexol injection and 4x finger prick sample collection; clinical review; questionnaire. Routine blood, urine and peritoneal fluid tests are also of interest.
干预措施: Iohexol Inj 300 MG/ML Diagnostic aid/agent used to measure glomerular filtration rate (GFR) (Diagnostic Test)
End stage kidney disease established on haemodialysis with >100ml / 24hour urine output
As per study description: individuals with established end stage chronic kidney disease undergoing haemodialysis. Interventions of interest include iohexol injection and 4x finger prick sample collection; clinical review; questionnaire. Routine blood and urine tests are also of interest.
干预措施: Iohexol Inj 300 MG/ML Diagnostic aid/agent used to measure glomerular filtration rate (GFR) (Diagnostic Test)
结局指标
主要结局
Iohexol measured glomerular filtration rate
时间窗: Assessed at each study visit through study completion, up to 6 months.
Serial timed dried blood samples taken over 24 hours after injection of iohexol will be tested for iohexol concentration. The measured glomerular filtration rate will be calculated by the rate of clearance (the area under the curve for concentration vs time plot) and corrected for body surface area (derived by weight and height) to give a value in ml/min/1.73m\^2
Creatinine based estimated glomerular filtration rate (Standard of care measure for kidney function in those not receiving renal replacement therapy)
时间窗: Assessed at each study visit while the participant has not yet started renal replacement therapy through study completion, up to 6 months.
Serum creatinine concentration (micromoles/liter) will be measured from a venous blood sample. This concentration along with participant age and sex will be used to calculate estimated glomerular filtration rate, corrected for body surface area, from internationally validated mathematical equations. Resuilts are reported in ml/min/1.73m\^2
Creatinine clearance corrected for body surface area (Standard of care measure for kidney function in those receiving peritoneal dialysis)
时间窗: Assessed at any study visit where the participant is established on peritoneal dialysis through to study completion, usually 48 hours after this visit.
Creatinine clearance will be calculated from paired blood (serum creatinine concentration) and 24 hour urine (urine creatinine concentration and volume) using validated mathematical equations. This will be corrected for body surface area (derived by weight and height) to give a value in ml/min/1.73m\^2
Residual renal clearance of creatinine and urea (Standard of care measure for kidney function in those receiving haemodialysis)
时间窗: Assessed at any study visit where the participant is established on haemodialysis dialysis through to study completion, usually 48 hours after this visit.
Renal function in haemodialysis can be derived from averaging the measured creatinine and urea clearance. This is calculated using internationally validated equations and requires multiple measurements. This includes: Pre- and post- dialyisis serum creatinine \& urea concentrations from 1st dialysis visit; timed urine collection between dialysis periods measured for urine creatinine and urea concentration, volume, time of collection and time between end of dialysis visit and starting urine collection; And predialsyis serum creatinine and urea from subsequent (2nd) dialysis session. This will be corrected for body surface area (derived by weight and height) to give a value in ml/min/1.73m\^2
次要结局
- Patient acceptability of performing measured GFR as assessed by participant questionnaire(24 hours. The questionnaire should take no more than 5 minutes but requires completion of the participant's first 24 hour mGFR testing to be done.)
- Number of iohexol finger prick samples correctly returned(Assessed at each study visit through study completion, up to 6 months.)
- Single sample iohexol measured GFR(Assessed at each study visit through study completion, up to 6 months.)
- eGFR calculated by novel markers(Assessed at each study visit through study completion, up to 6 months.)
- Presence of uraemic syndrome(Assessed at each study visit through study completion, up to 6 months.)
- Concentrations of markers of renal tubular function(Assessed at each study visit through study completion, up to 6 months.)