Norlund L, Fex G, Lanke J, Von Schenck H, Nilsson J E, Leksell H, Grubb A
Department of Clinical Chemistry, University Hospital, Lund, Sweden.
Scand J Clin Lab Invest. 1997 Oct;57(6):463-70. doi: 10.3109/00365519709084595.
Recent studies have indicated that serum and plasma cystatin C are better markers for glomerular filtration rate (GFR) than serum creatinine, ubiquitously used for this purpose. To fully exploit the value of serum and plasma cystatin C as GFR markers, reliable age and sex-correlated reference intervals are required. The present study comprised cystatin C determinations in plasma and sera from 259 individuals from a well-defined area in the southernmost part of Sweden. From demographic lists two men and two women were randomly selected from each one-year birth cohort above 20 years of age. No sex differences were found for plasma and serum cystatin C, whereas an increase in the cystatin C levels with age was noted, corresponding to the known age-related decrease in GFR. The following reference intervals are recommended for practical clinical use: S-Cystatin C (both sexes): 20-50 years, 0.70-1.21 mg l-1 and 50+ years, 0.84-1.55 mg l-1. The same samples were also used for determination of beta 2-microglobulin levels in order to calculate reference intervals for the beta 2-microglobulin/cystatin C-ratio, which is a more distinct marker for cell proliferation, particularly lymphoproliferation, than is the serum level of beta 2-microglobulin alone, since the ratio should be virtually uninfluenced by GFR. The beta 2-microglobulin/cystatin C-ratios were uninfluenced by sex and age and 1.45-2.43 is recommended as the serum reference interval for practical clinical use. Serum creatinine was determined in the same samples and the creatinine level was found to be strongly influenced by sex and weakly by age.
近期研究表明，血清和血浆胱抑素C作为肾小球滤过率（GFR）的标志物，比血清肌酐更好，血清肌酐一直被用于此目的。为了充分利用血清和血浆胱抑素C作为GFR标志物的价值，需要可靠的与年龄和性别相关的参考区间。本研究对来自瑞典最南部一个明确区域的259名个体的血浆和血清进行了胱抑素C测定。从人口统计学列表中，在20岁以上的每个一岁出生队列中随机选择两名男性和两名女性。未发现血浆和血清胱抑素C存在性别差异，然而，随着年龄增长，胱抑素C水平升高，这与已知的与年龄相关的GFR下降相对应。建议将以下参考区间用于实际临床应用：血清胱抑素C（男女）：20 - 50岁，0.70 - 1.21 mg l-1；50岁及以上，0.84 - 1.55 mg l-1。相同的样本还用于测定β2-微球蛋白水平，以计算β2-微球蛋白/胱抑素C比值的参考区间，该比值是细胞增殖（特别是淋巴细胞增殖）的更明显标志物，比单独的血清β2-微球蛋白水平更明显，因为该比值实际上不受GFR影响。β2-微球蛋白/胱抑素C比值不受性别和年龄影响，建议将1.45 - 2.43作为实际临床应用的血清参考区间。在相同样本中测定了血清肌酐，发现肌酐水平受性别影响较大，受年龄影响较小。
