Background Glomerular volume increases when demand exceeds nephron supply, which may lead to glomerulosclerosis. It is unclear if determinants of glomerular volume are consistent between populations that differ by severity of comorbidities.

Methods We studied kidney biopsy specimens from living kidney donors (n=2453) and patients who underwent radical nephrectomy for a renal tumor (n=780). We scanned specimen sections into high-resolution digital images, manually traced glomerular profiles, and calculated mean glomerular volumes using the Weibel–Gomez stereologic formula (separately for nonsclerosed glomeruli and globally sclerosed glomeruli). We then assessed the relationship of glomerular volume with age, clinical characteristics, and nephrosclerosis on biopsy specimen.

Results Compared with kidney donors, patients with tumors were older and more frequently men, obese, diabetic, or hypertensive, had more glomerulosclerosis and interstitial fibrosis on biopsy specimen, and had 12% larger nonsclerosed glomeruli (P<0.001). In both populations, male sex, taller height, obesity, hypertension, and proteinuria associated with larger nonsclerosed glomeruli to a similar extent. In patients with tumors, diabetes, glomerulosclerosis >25%, and interstitial fibrosis >25% also associated with larger nonsclerosed glomeruli. Independent clinical predictors of larger nonsclerotic glomeruli were family history of ESRD, male sex, taller height, obesity, diabetes, and proteinuria. After adjustment for these characteristics, nonsclerotic glomerular volume did not differ between populations and was stable up to age 75 years, after which it decreased with age. Many of these findings were also evident with globally sclerotic glomerular volume.

Conclusions Characteristics associated with glomerular volume are consistent between patient populations with low and high levels of comorbidity.

背景当需求超过肾脏供应时，肾小球体积增加，这可能导致肾小球硬化。尚不清楚因合并症的严重程度而不同的人群之间肾小球体积的决定因素是否一致。

方法我们研究了来自活体肾脏供体（n = 2453）和接受根治性肾切除术治疗肾肿瘤的患者（n = 780）的肾脏活检标本。我们将标本切片扫描成高分辨率的数字图像，手动追踪肾小球轮廓，并使用Weibel–Gomez立体公式（分别针对非硬化性肾小球和整体性硬化性肾小球）计算平均肾小球体积。然后，我们评估了活检标本中肾小球体积与年龄，临床特征和肾硬化之间的关系。

结果与肾脏供体相比，肿瘤患者年龄更大，男性，肥胖，糖尿病或高血压患者更为常见，在活检标本中肾小球硬化和间质纤维化程度更高，非硬化性肾小球增大了12％（P<0.001）。在这两个人群中，男性，较高的身高，肥胖，高血压和蛋白尿与较大的非硬化性肾小球相关程度相似。在患有肿瘤的患者中，糖尿病，肾小球硬化> 25％和间质纤维化> 25％也与较大的非硬化性肾小球相关。较大的非硬化性肾小球的独立临床预测因素是ESRD家族史，男性，身高，肥胖，糖尿病和蛋白尿。对这些特征进行调整后，人群之间的非硬化性肾小球体积没有差异，并且在75岁之前一直稳定，此后随着年龄的增长而下降。这些发现中的许多也与全球硬化性肾小球体积有关。

结论在合并症程度较低和较高的人群中，与肾小球体积相关的特征是一致的。