Stríbrná J, Schück O, Vítko S, Teplan V, Matl I, Skibová J, Stollová M
Klinika nefrologie IKEM, Praha.
Vnitr Lek. 1997 Oct;43(10):655-8.
In subjects with a transplanted kidney frequently tubular functions are impaired even when the glomerular filtration is within the normal range. In the present work the authors are dealing in more detail with the problem of tubular sodium reabsorption in the transplanted kidney. The purpose of the investigation was to assess to what extent these changes can be explained as the consequence of adaptational changes due to reduction of the number of nephrons and whether these changes have to be taken into consideration in the differential diagnosis of acute changes of graft function. The glomerular filtration rate (GF) was assessed on the basis of polyfructosan clearance, fractional sodium and potassium excretion (FENa and FEK) in a group of 12 subjects with a stabilized function of a transplanted kidney (group A), in 11 subjects after nephrectomy in healthy donors for transplantation (group B) and in 27 subjects after nephrectomy indicated for a pathological process in one kidney (group C). The mean values of GFR were as follows: Group A: 1.21 (+/- 0.19)ml/s/1.73 sq.m Group B: 1.19 (+/- 0.17)ml/s/1.73 sq.m Group C: 1.24 (+/- 0.21)ml/s/1.73 sq.m The mean values of GFR in different groups did not differ significantly. The mean values of FENa in different groups were as follows: Group A: 3.02 (+/- 1.59)% Group B: 2.05 (+/- 0.77)% Group C: 2.01 (+/- 1.17)% The mean value of FENa in group A was significantly higher than the mean value in group B (p < 0.01) and in group C (p < 0.01). The assembled findings support the idea that reduced tubular sodium reabsorption in the transplanted kidney (with a stabilized value of GFR) cannot be explained only as a manifestation of adaptation of tubular function as a result of the reduced number of functioning nephrons. The persisting osmotic sodium diuresis in the transplanted kidney must be viewed from the aspect of possibly impaired water preservation and the development of dehydration associated with a drop of GFR and must be differentiated from rejection.
在肾移植受者中，即使肾小球滤过率在正常范围内，肾小管功能也常常受损。在本研究中，作者更详细地探讨了移植肾中肾小管钠重吸收的问题。研究目的是评估这些变化在多大程度上可解释为由于肾单位数量减少导致的适应性变化的结果，以及在移植肾功能急性变化的鉴别诊断中是否必须考虑这些变化。基于多聚果糖清除率、钠和钾排泄分数（FENa和FEK），对12例移植肾功能稳定的受试者（A组）、11例健康供体肾切除后准备移植的受试者（B组）和27例因一侧肾脏病变而进行肾切除的受试者（C组）进行了肾小球滤过率（GF）评估。GFR的平均值如下：A组：1.21（±0.19）ml/s/1.73平方米；B组：1.19（±0.17）ml/s/1.73平方米；C组：1.24（±0.21）ml/s/1.73平方米。不同组的GFR平均值无显著差异。不同组的FENa平均值如下：A组：3.02（±1.59）%；B组：2.05（±0.77）%；C组：2.01（±1.17）%。A组的FENa平均值显著高于B组（p<0.01）和C组（p<0.01）。综合研究结果支持这样一种观点，即移植肾中肾小管钠重吸收减少（GFR稳定）不能仅解释为由于功能肾单位数量减少导致的肾小管功能适应性表现。必须从可能受损的水潴留以及与GFR下降相关的脱水发展方面来考虑移植肾中持续存在的渗透性钠利尿，并必须与排斥反应相鉴别。
