比较不同肾小球滤过率计算方法评价儿童慢性肾脏病肾功能的适用性

目的 肾小球滤过率(GFR)是评价肾功能的最好指标,可用直接检测法和公式估算法获得GFR,后者在临床实践中尤为常用,如24 h内生肌酐清除率、Schwartz公式以及Filler公式,但少有对这些计算方法在我国儿童慢性肾脏病(CKD)患者的适用性的研究.方法 选择2002年至2005年在我院住院、且符合入选标准和排除标准的CKD患儿为研究对象.将24 h内生肌酐清除率、Schwartz公式以及Filler公式估算的GFR(eGFR)与99mTc-DTPA肾动态显像(Gates法)测得的GFR(rGFR)进行比较.结果 入选30例患儿(男18例、女12例),平均年龄为9.4岁.CKD1期13例、CKD2期8例、CKD3期8例、CKD4期1例.CKD病因包括结构异常、肾小球肾炎、血管性疾病、肾病综合征和泌尿系结核.Bland-Altman分析显示24 h内生肌酐清除率的eGFR与rGFR的一致性相对最好;由24 h肌酐清除率和Schwartz公式得出的eGFR的准确性较Filler公式好.CKD1期时,由24 h内生肌酐清除率和Schwartz公式得出的eGFR过高估计rGFR,而由Filler公式得出的eGFR过低估计rGFR;CKD2期时,由24 h内生肌酐清除率得出的eGFR过低估计rGFR,而由Schwartz公式和Filler公式得出的eGFR过高估计rGFR.结论 3种公式获得的GFR的估计值与标准方法测得的GFR值之间存在显著差异,有待于今后开发更适用于我国儿童的肾功能估算方法.     

Schwartz公式推算原发性肾病综合征患儿肾小球滤过率

目的 了解原发性肾病综合征(PNS)患儿肾功能变化情况,比较肾小球滤过率(GFR)、血浆尿素氮(BUN)和肌酐清除率(Cr)对肾功能的评价作用.方法 使用酶法测定203例PNS患儿和100例健康儿童BUN和Cr,根据Schwartz公式推算GFR,并以此对肾功能进行分期.结果 肾病组BUN和Cr明显高于对照组,而GFR却显著降低;以GFR为分期标准,在203例PNS患儿中,肾功能1期占72.41%,2期占11.33%,3期占9.85%,4期占4.43%,5期占1.97%;GFR、BUN和Cr对PNS患儿肾功能异常的检出率差异有统计学意义,其中GFR最高.结论 PNS患儿存在不同程度的肾功能损害;Schwartz公式推算GFR可以作为临床评价PNS患儿肾功能改变的敏感指标.     

儿童慢性肾脏病营养状况及其影响因素分析

目的 了解慢性肾脏病（CKD）患儿营养状况及其影响因素,探讨能够预测营养状况的相关指标。方法 选取2009-2011年就诊于首都医科大学附属北京儿童医院肾脏内科的CKD患儿123例为CKD组, 正常儿童168名为正常对照组。测量两组身高（H）、 体重（W）、 肌酐、 胰岛素样生长因子结合蛋白3（IGFBP3）, 计算年龄标准体重（W/A）、 年龄标准身高（H/A）、 身高标准体重（W/H）、 体重指数（BMI）及肾小球滤过率（GFR）。对30例CKD组家长进行营养知识问卷调查。评价 CKD 儿童营养状况, 分析 GFR、 性别、 病程等因素与营养状况的相关性。 结果 CKD组W/A 70例（56.91%）降低,H/A 63例（51.22%）降低,W/H 60例（48.78%）降低,其发生率高于正常对照组（16.07%、18.45%、23、81%,P＜0.05）,与GFR呈显著正相关（r=0.552、0.368、0.539,P＜0.05）;CKD组血IGFBP3高于正常对照组,差异有统计学意义（t=2.725,P＜0.05）。超重和肥胖21例（17.07%）。76.67%（23/30） CKD患儿父母不了解营养知识。结论 营养不良是CKD儿童常见并发症,营养状况与肾功能相关。血IGFBP3与GFR可以作为CKD儿童营养状况的高危指标。定期营养指导、普及营养知识很重要。     

应用~(99m)Tc-DTPA肾动态显像测定正常儿童GFR及校正研究

目的肾小球滤过率(GFR)是肾脏功能评估的重要指标之一,本研究以~(99m)Tc-DTPA肾动态显像法测定儿童GFR并校正以获得准确结果。方法对99例(8周至12岁)肾功能正常的儿童实施99mTc-DTPA肾动态显像,Gate's法测得GFR,经核医学侧位影像实测肾脏深度作衰减校正,得出校正GFR(cGFR),并作体表面积标准化。受检者根据年龄分为5组,分别为8周至1岁、1~2岁、2~3岁、3~10岁、10~12岁。结果①第1组:8周至1岁,GFR(70±10)mL/min,cGFR(84±10)mL/min;第2组:1~2岁,GFR(79±6)mL/min,cGFR(94±7)mL/min;第3组:2~3岁,GFR(85±5)mL/min,cGFR(98±4)mL/min;第4组:3~10岁,GFR(84±6)mL/min,cGFR(102±6)mL/min;第5组:10~12岁,GFR(86±7)mL/min,cGFR(105±6)mL/min。②每组GFR和cGFR比较均有显著差异(P值均0.05)。③GFR经体表面积标准化,各组值均偏高。④与Schwartz公式估算值eGFR相比,大年龄组的cGFR更与之接近。⑤GFR 95%正常值范围:第1组:8周至1岁,GFR 50~90 mL/min,cGFR 60~104 mL/min;第2组:1~2岁,GFR 67~91 mL/min,cGFR 80~108 mL/min;第3组:2~3岁,GFR75~95 mL/min,cGFR 90~106 mL/min;第4组:3~10岁,GFR 72~96 mL/min,cGFR 90~114 mL/min;第5组:10~12岁,GFR 72~100 mL/min,cGFR 93~117 mL/min。结论 ~(99m)Tc-DTPA肾动态显像法可获得儿童GFR的正常参考值范围,为临床评估肾功能提供客观量化指标。     

湖南省听力障碍儿童慢性肾脏病流行病学调查

目的 调查湖南省听力障碍儿童慢性肾脏病（CKD）的患病情况。方法 运用横断面研究,采用多阶段整群抽样方法共抽取1 500名儿童作为研究样本,现场进行问卷调查、体格检查、实验室检查。结果 1 500名儿童中,纳入资料完整的儿童1 459名。CKD患病43例,患病率为2.95%,其中 < 7岁组患病率（5.8%,35/604）显著高于7~14岁组（0.9%,8/855）（P < 0.05）。43例CKD患儿中,表现为蛋白尿31例（72%）,表现为血尿27例（63%）,表现肾小球滤过率下降11例（26%）。43例CKD患儿中,CKD 1、2、3a、3b、4、5期患病例数分别为13、19、5、3、3、0例,分别占30%、44%、12%、7%、7%、0%。CKD患病率随听力障碍程度加重而升高（P < 0.01）。结论 湖南省听力障碍儿童中CKD的患病率较高,大部分处于CKD早期,学龄前期儿童多见。听力障碍程度与CKD的患病率相关。     

慢性肾脏病5期维持性血液透析患儿营养状态的评估

目的 研究儿童慢性肾脏病（CKD）5期维持性血液透析患者营养状态,探讨各营养评估指标的临床意义。方法 对21例CKD 5期维持性血液透析患儿按体重指数进行分组,根据人体测量指标、生物化学指标、炎症指标、残存肾功能及透析充分性指标、静息能量消耗指标等进行营养状态评估,分析营养不良患儿与营养正常患儿相关指标的差异。结果 21例患儿中,营养不良10例,营养正常11例。营养不良组与营养正常组人体测量指标之间差异有统计学意义（P < 0.05）;两组间瘦素、胰岛素样生长因子1的比较差异有统计学意义（P < 0.05）;两组间IL-1、IL-6、TNF-α的比较差异有统计学意义（P < 0.05）;两组间平均24 h残余尿量的比较差异有统计学意义（P < 0.05）。而两组间白蛋白、前白蛋白、胆固醇的比较差异无统计学意义;两组间尿素清除指数（Kt/V）及实测静息能量消耗值的比较差异亦无统计学意义。结论 人体测量指标、生物化学指标、残存肾功能、炎症因子对CKD 5期维持性血液透析患儿营养状况评估具有重要的价值,而静息能量消耗测定对于CKD 5期维持性血液透析患儿营养状况评估和监测的应用价值有待研究。     

单中心371例儿童慢性肾脏病2~5期回顾性研究

目的探讨儿童慢性肾脏病(CKD)的病因构成、并发症及治疗情况,为儿童CKD的综合管理提供依据。方法收集2012年1月至2018年12月在首都医科大学附属北京儿童医院肾脏科住院的CKD患儿临床资料,对其病因构成、并发症、初始治疗情况等信息进行回顾性调查及分析。结果1.本组371例CKD患儿中,男女比例为1.44∶1.00。年龄分期0~3岁35例,4~6岁54例,7~12岁189例,13~18岁93例。CKD 2期11例,CKD 3期59例,CKD 4期62例,CKD 5期239例。2.先天性肾脏和尿道畸形(CAKUT)135例,占36.39%;肾小球疾病77例,占20.76%;遗传性肾脏疾病21例,占5.66%;肾小管间质疾病12例,占3.23%;遗传代谢病4例,占1.08%;其他病因5例,占1.35%;病因不详117例,占31.64%。3.其中57例进行了肾活检,肾活检率为15.36%。病理类型以局灶节段性肾小球硬化(18例,31.58%)、硬化性肾小球肾炎(13例,22.81%)和肾小管间质肾病(10例,17.54%)为主。4.贫血和继发性甲状旁腺功能亢进(SHPT)是最常见的并发症,分别为289例(77.90%)和271例(73.05%),其次为高血压[183例(49.33%)]、心血管疾病[139例(37.47%)]和蛋白质能量消耗[51例(13.75%)]。CKD 5期患儿高血压、贫血、SHPT和心血管疾病均明显高于CKD 2~4期,差异均有统计学意义(χ^2=50.03、122.36、77.07、64.89,均P<0.01)。肾小球疾病的高血压和心血管疾病发生率高于CAKUT,差异均有统计学意义(χ^2=65.63、40.89,均P<0.01)。CAKUT的蛋白质能量消耗发生率高于肾小球疾病,差异有统计学意义(χ^2=10.58,P<0.01)。5.共190例患儿需进行初始肾脏替代治疗,血液透析129例(67.89%),腹膜透析31例(16.32%),拒绝治疗30例(15.79%),初始移植0例。结论CKD患儿CAKUT为首位病因。本中心CKD 5期CAKUT和肾小球疾病所占比例相近。儿童CKD最常见并发症为贫血。高血压、贫血、SHPT和心血管疾病等随着CKD分期进展呈增多趋势。SHPT多发生于CKD 4期以上患儿。不同病因CKD患儿并发症发生率不同。本中心初始肾脏替代治疗以血液透析为主。     

血清胱蛋白酶C对评估儿童早期肾功能损害的临床意义

由于检测血清肌酐 (Scr)来反映肾小球滤过功能 (GFR)可受到多种因素的影响 ,故其敏感性和准确性较差。自Bokenkamp 等报道血清胱蛋白酶C(CysC)作为检测儿科肾功能的指标 ,近来已越来越受到重视[1]。为此 ,我院测定了236例肾脏疾病患儿血清CysC浓度并与Scr进行对照 ,其中17例患儿虽然Scr正常但血清CysC已有明显增高。因此本研究旨在探讨血清CysC对评估小儿早期肾功能损害的临床意义。资料与方法一、对象2000年10月～2002年4月肾脏疾病住院患儿236例 ,有24例患儿血清CysC增高 ,其中早期肾功能损害17例 ,肾功能不全7例。肾功能衰竭诊断…     

儿童原发性膜性肾病16例病理特点与远期预后

目的 了解儿童原发性膜性肾病(IMN)病理特点及其远期预后。方法 回顾性收集1979至2010年6月复旦大学附属儿科医院肾脏风湿科经病理诊断为IMN的连续病例为研究对象,分析一般情况、临床表现、病理特点、治疗和随访情况,探讨其远期预后。结果 16例IMN患儿进行分析,占同期肾穿刺活检病例（1 710例）的0.94%。男10例,女6例,年龄2～12岁,平均（5.2±2.6）岁。①临床表现以肾病综合征为主（11例,68.8%）,无症状性蛋白尿5例（31.2%）,伴有高血压2例(12.5%）,起病时伴有肾功能不全2例（12.5%）。②14/16例行肾组织电镜检查,其中Ⅰ期6/14例（42.9%）,Ⅰ~Ⅱ期6/14例（42.9%）,Ⅱ期1/14例（7.1%）,Ⅱ~Ⅲ期1/14例（7.1%）。病理学检查均未见肾小管萎缩、间质纤维化等肾小管间质损伤。③未达到大量蛋白尿标准的7例患儿予随访观察,其中1例病情进展予激素和免疫抑制剂治疗;达到大量蛋白尿标准的9例患儿均予足量激素(2 mg·kg-1·d-1)治疗,其中5例激素依赖或耐药加用免疫抑制剂治疗。至2010年6月,2例失访,14例IMN患儿随访12~91个月,平均（34.0±18.7）个月,在起病后3~16个月均达完全缓解,无一例进展至慢性肾脏疾病;2例起病时伴肾功能不全的患儿肾功能均恢复。结论 儿童IMN临床表现以肾病综合征为主,小年龄、病理分期较轻且不伴肾小管间质损伤患儿的预后相对较好。     

儿童慢性肾脏病贫血诊断与治疗专家共识

正贫血是慢性肾脏病(chronic kidney disease,CKD)患儿的常见并发症,CKD 1～5期均可发生,且随肾功能下降逐渐增高,CKD 5期时贫血已非常普遍[1-3]。与成人相比,儿童CKD贫血发生较早,进展速度快,不仅影响患儿体内组织氧的供应及     

Measurement of renal function in patients with Fabry disease

Appropriate measurement of the glomerular filtration rate (GFR) is important for the assessment of renal function. This paper reviews the methods used to assess GFR in clinical trials of enzyme replacement therapy (ERT) in patients with Fabry disease, which include inulin clearance, 24-hour creatinine clearance, chromium ethylene diamine tetraacetate (⁵¹Cr-EDTA) clearance and cystatin C concentrations. GFR has also been estimated using calculations based on creatinine clearance (the Cockcroft–Gault formula) and the Modification of Diet in Renal Disease (MDRD) equation. Analysis of the results of these studies shows that there are striking discrepancies between estimated and measured GFR. For example, the MDRD equation overestimates GFR in patients with Fabry disease who have normal renal function. In addition, cystatin C has been shown to be of limited use for measuring renal function during ERT, because it is influenced by other factors such as age, gender and weight.
Conclusion: The use of exact methods, such as inulin clearance, ¹²⁴I-iothalamate, ⁹⁹mTc-DTPA, ⁵¹Cr-EDTA and iohexol, appears to be mandatory for a robust evaluation of the effects of ERT on GFR in patients with Fabry disease.     

How to monitor renal function in pediatric solid organ transplant recipients

Abstract:  The aim is to review the tools for early detection of renal dysfunction after pediatric solid organ transplantation. Currently, the most widely used marker for detection of renal dysfunction involves measurement of GFR. Inulin clearance forms the "gold standard" method for measuring GFR; however, nuclear medicine methods (⁵¹Cr EDTA and ⁹⁹Tc DTPA isotope clearance studies) have replaced inulin clearance. The measurement of serum creatinine has a low sensitivity for the early detection of renal damage. The Schwartz formula using patient height and serum creatinine requires center-specific constants and has limitations associated with creatinine determination. These limitations may be overcome using a cystatin C-based GFR estimation. In diabetic nephropathy, and more recently in hemolytic uremic syndrome, microalbuminuria has been established as a useful screening tool for renal damage, while its predictive value in the transplantation setting needs to be established. All transplant recipients should be screened for hypertension. Early referral for ambulatory 24-h blood pressure monitoring and involvement of pediatric nephrologists should be considered. All pediatric solid organ transplant recipients receiving CNI should be screened regularly for high blood pressure and early evidence of renal damage using either GFR scans or cystatin C-based GFR estimations.     

Estimation of Glomerular Filtration Rate in Children Using 99m-Technetium DTPA

ABSTRACT. The usefulness of radionuclide imaging studies with 99m-technetium diethylenetriaminepen-taacetic acid (Tc-DTPA) for quantitating the glomerular filtration rate (GFR) in children was studied. This was compared to the conventional methods for measuring GFR using 51-chromium-EDTA clearance (Cr-EDTA), creatinine clearance and a height/plasma creatinine formula. In the 22 children studied, the correlation coefficient between renal uptake of DTPA and Cr-EDTA was 0.90 ( p <0.001). In contrast, there was a poorer correlation between Cr-EDTA and creatinine clearance ( r =0.69) or the derived GFR using height/creatinine formula ( r =0.83). The regression line between Tc-DTPA uptake and Cr-EDTA clearance was used to derive a formula for calculating the predicted GFR. This was tested in 10 additional children, and the correlation between the predicted GFR and measured GFR (using Cr-EDTA clearance studies) was 0.92 ( p <0.001). Quantitative estimation of the GFR during renal imaging studies is a feasible and convenient method of assessing renal function.     

Measurement of renal function in patients with Fabry disease

Appropriate measurement of the glomerular filtration rate (GFR) is important for the assessment of renal function. This paper reviews the methods used to assess GFR in clinical trials of enzyme replacement therapy (ERT) in patients with Fabry disease, which include inulin clearance, 24-hour creatinine clearance, chromium ethylene diamine tetraacetate (51Cr-EDTA) clearance and cystatin C concentrations. GFR has also been estimated using calculations based on creatinine clearance (the Cockcroft-Gault formula) and the Modification of Diet in Renal Disease (MDRD) equation. Analysis of the results of these studies shows that there are striking discrepancies between estimated and measured GFR. For example, the MDRD equation overestimates GFR in patients with Fabry disease who have normal renal function. In addition, cystatin C has been shown to be of limited use for measuring renal function during ERT, because it is influenced by other factors such as age, gender and weight. Conclusion: The use of exact methods, such as inulin clearance, 124I-iothalamate, 99mTc-DTPA, 51Cr-EDTA and iohexol, appears to be mandatory for a robust evaluation of the effects of ERT on GFR in patients with Fabry disease.     

Inaccuracy of glomerular filtration rate estimation from height/plasma creatinine ratio.

Use of a height/plasma creatinine formula to estimate glomerular filtration rate (GFR) is simpler and less invasive than renal or plasma clearance methods. The aim of this study was to determine whether these formulas enabled accurate prediction of GFR measured from the plasma clearance of 51Cr labelled ethylenediaminetetra-acetic acid (51Cr-EDTA). Thirty nine patients underwent GFR measurement at least six months after potentially nephrotoxic chemotherapy. Altman-Bland analysis was performed on the measured GFR and that estimated simultaneously using the original and a modified Counahan-Barratt formula and the Schwartz formula. The limits of agreement of the estimated GFR with the measured GFR were unacceptably wide in each case, despite highly significant correlation coefficients. The bias was smallest for the modified Counahan-Barratt formula. Use of these formulas to estimate GFR in children is insufficiently accurate for research purposes and has limitations in clinical practice. Furthermore, use of correlation coefficients to evaluate different methods of measuring GFR is inappropriate.     

Inaccuracy of glomerular filtration rate estimation from height/plasma creatinine ratio

Use of a height/plasma creatinine formula to estimate glomerular filtration rate (GFR) is simpler and less invasive than renal or plasma clearance methods. The aim of this study was to determine whether these formulas enabled accurate prediction of GFR measured from the plasma clearance of 51Cr labelled ethylenediaminetetra-acetic acid (51Cr-EDTA). Thirty nine patients underwent GFR measurement at least six months after potentially nephrotoxic chemotherapy. Altman-Bland analysis was performed on the measured GFR and that estimated simultaneously using the original and a modified Counahan-Barratt formula and the Schwartz formula. The limits of agreement of the estimated GFR with the measured GFR were unacceptably wide in each case, despite highly significant correlation coefficients. The bias was smallest for the modified Counahan-Barratt formula. Use of these formulas to estimate GFR in children is insufficiently accurate for research purposes and has limitations in clinical practice. Furthermore, use of correlation coefficients to evaluate different methods of measuring GFR is inappropriate.     

Assessment of glomerular filtration rate in infants. Comparison of three methods used in clinical practice

Glomerular filtration rate was assessed in 66 infants less than 1 year of age. Results obtained by 3 different routine methods were compared to those obtained by the standard inulin clearance (GFR): 1. clearance values calculated from plasma creatinine concentration (mg/dl) and height (cm), using a k value of 0.55 derived from inulin clearance did not reliably reflect GFR (Y = 37.5 + 0.51 Cin, r = 0.82); 2. creatinine clearance values calculated over 3 h overestimated standard inulin clearance at all levels of GFR below 100 ml/min.1.73m2 (Y = 25.1 + 0.75 Cin, r = 0.77). 3. Clearance values calculated as the sum of twice the creatinine clearance plus the urea clearance, divided by 3, overestimated the standard inulin clearance at low levels of GFR and underestimated it at high GFR (Y = 20.6 + 0.66 Cin, r = 0.82). The study of several techniques for estimating GFR in infants demonstrates that there is no ideal substitute for the traditional inulin clearance when precise measurement of glomerular filtration rate is needed, and that simple 3 h creatinine clearances represent a satisfactory and rational estimate of GFR in clinical practice.     

Evaluation of Renal Function and Morphology in Children by 99mTc-DTPA Gamma Camera Renography

ABSTRACT. The purpose of the present investigation was to evaluate the use of ^99mTc-DTPA (diethylene-triaminepenta-acetate) gamma camera renography for the study of kidney function as well as morphology. Sixty-nine children with urinary tract infection or congenital hydronephrosis aged 6 days to 13.6 years were studied. A method for determination of the glomerular filtration rate (GFR) from the recorded curves without use of blood or urine samples was tested in 65 consecutive children. From each renogram an uptake index was determined. After a weight/height correction the sum of right and left kidney uptake index correlated with total GFR determined from plasma clearance of ⁵¹Cr-EDTA (ethylenediaminetetra-acetate) measured on the same day ( r = 0.96). The relative standard error of estimating GFR from the renograms was 10.7 % at GFR = 100 ml/min and 14.6 % at GFR = 50 ml/min. In a subgroup including 20 children no difference was found in kidney morphology and length studied by renography and intravenous urography, the latter providing more details concerning the urinary tract. Relative kidney length did not correlate with relative renal function determined by renography, emphasizing the difficulty in determination of relative renal function by urography. In conclusion, not only relative but also absolute renal function (GFR) can be determined in children by ^99mTc-DTPA renography; at the same time kidney and urinary tract morphology are evaluated. In our hands, ^99mTc-DTPA renography has become a useful diagnostic tool, lowering the need for the more cumbersome intravenous urography and ⁵¹Cr-EDTA plasma clearance. However, intravenous urography is mandatory for the detailed study of the urinary tract, and use of the ⁵¹Cr-EDTA plasma clearance technique is necessary when a very reliable determination of GFR is wanted.     

Investigating current practices in renal function measurement and carboplatin dosing in children with cancer – a UK perspective

Abstract

Renal function-based carboplatin dosing is a well-accepted practice in pediatric oncology. However, the accuracy of this approach is only as precise as the method of kidney function measurement, most commonly involving determination of glomerular filtration rate (GFR). Recent work by the Children’s Oncology Group has raised concerns over nuclear medicine-based methodologies used to calculate GFR across US clinical centers. Current practices of GFR measurement, methods used to calculate carboplatin dosage and the utility of therapeutic drug monitoring were investigated in 21 UK primary pediatric oncology treatment centers through a questionnaire-based study. Information obtained was compared to results previously published in 2008 following a similar survey. In relation to GFR measurement, the main changes observed were a shift toward a greater number of samples being taken following tracer administration and an increase in number of centers using the Brochner-Mortensen correction factor. In relation to the use of renal function assessment data to inform dosing, EDTA elimination half-life in conjunction with body weight was used to calculate carboplatin dose in 18/21 (86%) centers, with uncorrected GFR and body weight utilized in 9/21 (43%) centers. A total of 14/21 (67%) centers utilize therapeutic drug monitoring approaches to carboplatin treatment in defined patient groups including neonates and infants. Results suggest that while GFR measurement across UK centers is relatively consistent, some uncertainties remain. In addition, for patient sub-populations where there are concerns over the potential for marked inter-patient variability in carboplatin exposures, adaptive dosing approaches are now well established.     

Renal function assessment in child and adolescent heart transplant recipients during routine cardiac catheterization

CKD identification after pediatric heart transplantation (PHT) is limited by inaccuracies in estimates of GFR. We hypothesized that GFR can be measured by a modified iohexol clearance protocol in PHT recipients and that the CKiD formula provides a better estimate of GFR than other estimating equations. A cross‐sectional study of PHT recipients, ages 2–18 yr, undergoing coronary angiography was undertaken. The angiography dose of iohexol was divided by the area under the curve from three iohexol levels post‐infusion to calculate GFR. Agreement between iGFR and multiple estimating equations (eGFR) was assessed. In 31 subjects, median age was 15.0 yr (IQR 7.6, 16.6). Mean iGFR was 93.8 (s.d. 22.5) mL/min/1.73 m²; 16 (52%) had an iGFR <90 mL/min/1.73 m². The full CKiD formula (mean eGFR 88.9, s.d. 14.9) had low bias (?5.0), narrowest 95% limits of agreement (?42.0, 32.1), highest 30% (94%) and 10% (52%) accuracy, and highest correlation coefficient (0.576) relative to iGFR. We describe a novel modified iohexol clearance method to assess GFR after PHT. Over half of the cohort had an iGFR <90, suggesting CKD. The full CKiD formula performs best with respect to bias, accuracy, and correlation.