Krüger C, Höper K, Weissörtel R, Hensen J, Dörr H G
University Hospital for Children, University of Erlangen-Nürnberg, Germany.
Eur J Pediatr. 1996 Oct;155(10):858-61. doi: 10.1007/BF02282834.
In congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency, measurement of plasma renin activity (PRA) has been the method of choice in diagnosing salt loss and in monitoring adequacy of mineralocorticoid replacement therapy. Due to methodological problems in PRA determinations, direct immunoradiometric assays for the measurement of active renin concentration have been developed. We measured PRA and active renin concentrations simultaneously in 39 patients with CAH (30 salt-wasting, 9 simple virilizing) to evaluate the potential role of this new method in the management of this disease. PRA was determined with an enzymatic assay (sample volume: 2 x 1000 microliters plasma), active renin concentration with a direct immunoradiometric assay (sample volume: 2 x 200 microliters plasma or serum). We found a highly significant correlation between active renin and PRA in our patients (P < 0.001), as previously shown in healthy subjects. Active renin was as reliable as PRA to assess the quality of mineralocorticoid replacement.
In children, active renin determination is preferable to PRA determination because of methodological advantages and a smaller sample volume. It correlates well with PRA and determines the activation of the renin-angiotensin system as precisely as PRA. Active renin determination is useful in the surveillance of mineralocorticoid replacement therapy in CAH.
在因21-羟化酶缺乏所致的先天性肾上腺皮质增生症（CAH）中，血浆肾素活性（PRA）测定一直是诊断失盐以及监测盐皮质激素替代治疗是否充分的首选方法。由于PRA测定存在方法学问题，已开发出用于测定活性肾素浓度的直接免疫放射分析方法。我们同时测定了39例CAH患者（30例失盐型、9例单纯男性化型）的PRA和活性肾素浓度，以评估这种新方法在该疾病管理中的潜在作用。PRA采用酶法测定（样本量：2×1000微升血浆），活性肾素浓度采用直接免疫放射分析方法测定（样本量：2×200微升血浆或血清）。我们发现患者的活性肾素与PRA之间存在高度显著的相关性（P<0.001），正如之前在健康受试者中所显示的那样。活性肾素在评估盐皮质激素替代质量方面与PRA一样可靠。
在儿童中，由于方法学优势和样本量较小，测定活性肾素比测定PRA更可取。它与PRA相关性良好，并且在确定肾素-血管紧张素系统的激活方面与PRA一样精确。活性肾素测定在CAH盐皮质激素替代治疗的监测中很有用。
