Chromatographic system for the simultaneous measurement of plasma 18-hydroxy-11-deoxycorticosterone and 18-hydroxycorticosterone by radioimmunoassay: reference data for neonates and infants and its application in aldosterone-synthase deficiency.
J Chromatogr B Analyt Technol Biomed Life Sci 2003;
785:293-301. [PMID:
12554142 DOI:
10.1016/s1570-0232(02)00921-2]
[Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A new chromatographic system for the steroid precursor separation and a sensitive radioimmunoassay system for the subsequent measurement of 18-hydroxy-11-deoxycorticosterone and 18-hydroxycorticosterone has been developed. 18-Hydroxy-11-deoxycorticosterone and 18-hydroxycorticosterone were extracted with methylene chloride and separated from cross-reacting steroids by Sephadex LH-20 column chromatography. Anti-18-hydroxy-11-deoxycorticosterone and anti-18-hydroxycorticosterone antibodies raised in rabbits were used. The lower detection limit of the assay is 0.03 nmol/l and 0.128 nmol/l for 18-hydroxy-11-deoxycorticosterone and 18-hydroxycorticosterone, respectively. Normal values for this assay in 128 healthy neonates and infants aged 0-5 months were established as a basis for the early hormonal diagnosis of aldosterone synthase deficiency types I and II. Its application for the diagnosis of aldosterone synthase deficiency is demonstrated in two patients with homozygous mutation/deletion in the encoding CYP11B2 gene.
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