Elsherbiny Hisham E, Alexander Mariam P, Kremers Walter K, Park Walter D, Poggio Emilio D, Prieto Mikel, Lieske John C, Rule Andrew D
Division of Nephrology and Hypertension.
Division of Anatomic Pathology.
Clin J Am Soc Nephrol. 2014 Nov 7;9(11):1892-902. doi: 10.2215/CJN.02560314. Epub 2014 Oct 15.
The relationship of kidney function and CKD risk factors to structural changes in the renal parenchyma of normal adults is unclear. This study assessed whether nephron hypertrophy and nephrosclerosis had similar or different associations with kidney function and risk factors.
DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: From 1999 to 2009, 1395 living kidney donors had a core needle biopsy of their donated kidney during transplant surgery. The mean nonsclerotic glomerular volume and glomerular density (globally sclerotic and nonsclerotic) were estimated using the Weibel and Gomez stereologic methods. All tubules were counted in 1 cm(2) of cortex to determine a mean profile tubular area. Nephron hypertrophy was identified by larger glomerular volume, larger profile tubular area, and lower nonsclerotic glomerular density. Nephrosclerosis was identified by higher globally sclerotic glomerular density.
The mean (± SD) age was 44 ± 12 years, 24-hour urine albumin excretion was 5 ± 7 mg, measured GFR was 103 ± 17 ml/min per 1.73 m(2), uric acid was 5.2 ± 1.4 mg/dl, and body mass index was 28 ± 5 kg/m(2). Of the study participants, 43% were men, 11% had hypertension, and 52% had a family history of ESRD. Larger glomerular volume, larger profile tubular area, and lower nonsclerotic glomerular density were correlated. Male sex, higher 24-hour urine albumin excretion, family history of ESRD, and higher body mass index were independently associated with each of these measures of nephron hypertrophy. Higher uric acid, higher GFR, and older age were also independently associated with some of these measures of nephron hypertrophy. Hypertension was not independently associated with measures of nephron hypertrophy. However, hypertension and older age were independently associated with higher globally sclerotic glomerular density.
Nephron hypertrophy and nephrosclerosis are structural characteristics in normal adults that relate differently to clinical characteristics and may reflect kidney function and risk factors via separate but inter-related pathways.
正常成年人的肾功能、慢性肾脏病（CKD）危险因素与肾实质结构改变之间的关系尚不清楚。本研究评估了肾单位肥大和肾硬化与肾功能及危险因素之间的关联是相似还是不同。
设计、地点、参与者及测量方法：1999年至2009年期间，1395名活体肾供者在移植手术期间对其捐献的肾脏进行了粗针活检。采用韦贝尔（Weibel）和戈麦斯（Gomez）体视学方法估算非硬化性肾小球的平均体积和肾小球密度（包括整体硬化和非硬化的）。在1平方厘米的皮质中对所有肾小管进行计数，以确定平均剖面肾小管面积。肾单位肥大通过较大的肾小球体积、较大的剖面肾小管面积和较低的非硬化性肾小球密度来确定。肾硬化通过较高的整体硬化性肾小球密度来确定。
平均（±标准差）年龄为44±12岁，24小时尿白蛋白排泄量为5±7毫克，实测肾小球滤过率（GFR）为每1.73平方米103±17毫升/分钟，尿酸为5.2±1.4毫克/分升，体重指数为28±5千克/平方米。研究参与者中，43%为男性，11%患有高血压，52%有终末期肾病（ESRD）家族史。较大的肾小球体积、较大的剖面肾小管面积和较低的非硬化性肾小球密度相互关联。男性、较高的24小时尿白蛋白排泄量、ESRD家族史和较高的体重指数与这些肾单位肥大的指标均独立相关。较高的尿酸、较高的GFR和较高的年龄也与其中一些肾单位肥大的指标独立相关。高血压与肾单位肥大的指标无独立相关性。然而，高血压和较高的年龄与较高的整体硬化性肾小球密度独立相关。
肾单位肥大和肾硬化是正常成年人的结构特征，它们与临床特征的关系不同，可能通过独立但相互关联的途径反映肾功能和危险因素。
