Gates Gary F
Nuclear Medicine Department, Providence St. Vincent Medical Center, Portland, OR 97225, USA.
Clin Nucl Med. 2004 Apr;29(4):231-7. doi: 10.1097/01.rlu.0000117998.67737.ae.
Glomerular filtration rate (GFR) and effective renal plasma flow (ERPF) were determined in 92 patients to calculate filtration fraction (GFR/EFPR) and evaluate its change in renal diseases. This information was used as the rationale for a renogram protocol using DTPA (to estimate GFR) and MAG3 (to produce images and curves).
Individual kidney GFR and ERPF were determined by gamma camera techniques using Tc-99m DTPA and I-131 OIH. Two hundred sixty-one determinations were performed in 92 patients who in turn were grouped into 4 categories: normal, obstruction, renal vascular disease, and chronic insufficiency.
Mean filtration fractions in normal patients and those with obstruction were similar (0.16 and 0.15, respectively), whereas they were lower in renal vascular disease (0.11) and chronic renal insufficiency (0.08). Low filtration fraction indicates disproportionate loss of GFR compared with ERPF and was the pattern observed with advancing renal disease in most patients. The exception was ATN or contrast nephropathy when filtration fraction was increased (0.22) as a result of disproportionate loss of ERPF compared with GFR.
OIH is no longer available in the United States, and MAG3 is now used as the renal tubular agent in renography. Clearance of MAG3 does not directly measure ERPF, but this might not be a significant loss in clinical practice if GFR is measured during renography because it is more adversely affected by renal disease than ERPF (with the exception of ATN and contrast nephropathy). Accordingly, a renogram protocol is presented for the combined use of DTPA and MAG3 resulting in GFR estimation (from DTPA) while yielding superior renal images and renogram curves from MAG3.
对92例患者测定肾小球滤过率（GFR）和有效肾血浆流量（ERPF），以计算滤过分数（GFR/EFPR）并评估其在肾脏疾病中的变化。这些信息被用作采用二乙三胺五乙酸（DTPA，用于估计GFR）和巯基乙酰三甘氨酸（MAG3，用于生成图像和曲线）的肾图检查方案的理论依据。
采用γ相机技术，使用锝-99m DTPA和碘-131邻碘马尿酸（OIH）测定个体肾脏的GFR和ERPF。对92例患者进行了261次测定，这些患者依次被分为4类：正常、梗阻、肾血管疾病和慢性肾功能不全。
正常患者和梗阻患者的平均滤过分数相似（分别为0.16和0.15），而在肾血管疾病（0.11）和慢性肾功能不全（0.08）患者中则较低。低滤过分数表明与ERPF相比，GFR不成比例地降低，这是大多数患者肾脏疾病进展时观察到的模式。例外情况是急性肾小管坏死（ATN）或造影剂肾病，此时由于与GFR相比ERPF不成比例地降低，滤过分数增加（0.22）。
在美国，OIH已不再可用，目前MAG3被用作肾图检查中的肾小管显像剂。MAG3的清除率并不直接测量ERPF，但如果在肾图检查期间测量GFR，这在临床实践中可能并非重大损失，因为与ERPF相比，GFR受肾脏疾病的影响更大（ATN和造影剂肾病除外）。因此，本文提出了一种联合使用DTPA和MAG3的肾图检查方案，该方案可通过DTPA估计GFR，同时通过MAG3获得优质的肾脏图像和肾图曲线。
