Pollock C, Liu P L, Györy A Z, Grigg R, Gallery E D, Caterson R, Ibels L, Mahony J, Waugh D
Department of Medicine, University of Sydney, Australia.
Kidney Int. 1989 Dec;36(6):1045-9. doi: 10.1038/ki.1989.299.
To aid investigation into the clinical problem of hematuria, assessment of abnormalities in the shape of red cells in the urine (dysmorphism) is gaining popularity in nephrology. However, there is uncertainty in the literature regarding both the number of red blood cells (RBC) in normal urine, as well as the quantification of dysmorphism. We have shown that in normal urine (N = 27) the number of RBC is less than 2,000/ml as assessed by scanning electron microscopy of filtered urine specimens from normal volunteers without known renal disease, which compared to less than 1,000/ml by centrifugation and phase contrast microscopy of the same specimen. To determine whether dysmorphism of urinary red blood cells was a significant predictor of glomerular disease we compared the number of dysmorphic cells in the urine of patients with biopsy proven glomerulonephritis (GN), before and immediately after renal biopsy. We also compared the number of dysmorphic cells in patients with glomerulonephritis to those with lower urinary tract bleeding. Renal biopsy caused significant dysmorphic hematuria, indicating that dysmorphism suggests renal rather than glomerular bleeding. Although patients with GN had significantly more dysmorphic urinary RBC when compared to those with lower tract urinary bleeding, the overlap was such that one could only be confident of renal hematuria if they accounted for greater than 75% of the total number of RBC. Non renal hematuria is present if number of dysmorphic cells is less than 17% of total RBC. Thus dysmorphism of urinary RBC is a useful diagnostic tool, but only if strict criteria established for each laboratory are adhered to.
为了辅助对血尿这一临床问题的研究，评估尿中红细胞形态异常（异形性）在肾脏病学中越来越受到关注。然而，文献中对于正常尿液中红细胞（RBC）的数量以及异形性的量化存在不确定性。我们已经表明，在正常尿液（N = 27）中，通过对无已知肾脏疾病的正常志愿者的滤过尿液标本进行扫描电子显微镜评估，RBC数量少于2000/ml，而对同一标本进行离心和相差显微镜检查时，该数量少于1000/ml。为了确定尿红细胞异形性是否是肾小球疾病的重要预测指标，我们比较了经活检证实为肾小球肾炎（GN）的患者在肾活检前和肾活检后立即尿液中异形细胞的数量。我们还比较了肾小球肾炎患者与下尿路出血患者尿液中异形细胞的数量。肾活检导致明显的异形血尿，这表明异形性提示肾脏出血而非肾小球出血。尽管与下尿路出血患者相比，GN患者尿液中的异形RBC明显更多，但两者存在重叠，以至于只有当异形RBC占RBC总数超过75%时才能确定为肾性血尿。如果异形细胞数量少于RBC总数的17%，则存在非肾性血尿。因此，尿RBC异形性是一种有用的诊断工具，但前提是要严格遵守每个实验室制定的标准。
