Englund M, Berg U
Department of Paediatrics, Karolinska Institutet, Huddinge University Hospital, Sweden.
Transplantation. 2000 Nov 15;70(9):1342-7. doi: 10.1097/00007890-200011150-00013.
Kidney donors and transplant recipients may be at risk of complications from glomerular hyperfiltration of the single kidney. It has been assumed that tests of the existence of renal functional reserve [delta glomerular filtration rate (deltaGFR), delta effective renal plasma flow (deltaERPF)] can be used to demonstrate hyperfiltration. It would therefore be of interest to evaluate the response of the kidney graft to a protein load. i.e., testing the renal reserve and to find out whether a reduction in baseline GFR is preceded by a loss of deltaGFR.
We repeatedly studied the change in GFR and renal plasma flow (ERPF) after an oral protein load in 30 children after renal transplantation (Tx). Follow-up time was 1.0-8.0 years. Renal function was evaluated with the clearances of inulin and para-aminohippuric acid (PAH). Seven recipient/donor pairs were examined twice (median 0.3 and 4 years, after Tx).
The baseline GFR and ERPF remained stable throughout the follow-up and the increase after stimulation (deltaGFR and deltaERPF) did not change in the whole group of Tx children over the years. However, a reduction in the baseline GFR from the first to the last investigation occurred in 23 of 30 children. In the 23 patients whose baseline GFR decreased, deltaGFR was still preserved. In the recipient/donor pairs, the baseline GFR and ERPF were the same, but on the second investigation, donors showed higher deltaGFR.
Despite fairly low baseline GFR and ERPF values in the Tx children, no change occurs in the capacity to increase GFR and ERPF after a protein load during follow-up, which suggests that they are not maximally hyperfiltrating.
肾供体和肾移植受者可能面临单肾肾小球高滤过并发症的风险。人们认为，肾功能储备测试[肾小球滤过率变化（ΔGFR）、有效肾血浆流量变化（ΔERPF）]可用于证明高滤过。因此，评估肾移植受者对蛋白质负荷的反应，即测试肾储备，并了解在基线肾小球滤过率降低之前ΔGFR是否降低，将是很有意义的。
我们对30例肾移植（Tx）后儿童口服蛋白质负荷后肾小球滤过率（GFR）和肾血浆流量（ERPF）的变化进行了反复研究。随访时间为1.0 - 8.0年。通过菊粉清除率和对氨基马尿酸（PAH）清除率评估肾功能。对7对受者/供体进行了两次检查（Tx后中位数为0.3年和4年）。
在整个随访过程中，基线GFR和ERPF保持稳定，多年来Tx儿童组刺激后增加量（ΔGFR和ΔERPF）没有变化。然而，30名儿童中有23名从首次到最后一次检查时基线GFR降低。在基线GFR降低的23例患者中，ΔGFR仍然保留。在受者/供体对中，基线GFR和ERPF相同，但在第二次检查时，供体的ΔGFR更高。
尽管Tx儿童的基线GFR和ERPF值相当低，但随访期间蛋白质负荷后增加GFR和ERPF的能力没有变化，这表明他们没有最大程度地高滤过。
