MEASUREMENT OF URINARY ANDROGEN SULFATES WITHOUT PREVIOUS HYDROLYSIS - A TOOL TO INVESTIGATE ADRENARCHE - DETERMINATION OF TOTAL 17-KETOSTEROID SULFATES

According to published data the group of urinary total 17-ketosteroid sulfates appears to represent an index of overall adrenal androgen pro duction, at least before the onset of puberty. To quantify total 17-ke tosteroid sulfates a modified colorimetric assay based on the Zimmerma nn reaction was validated. 17-ketosteroid sulfates were measured witho ut previous hydrolysis (as conjugated Zimmermann chromogens against au thentic dehydroepiandrosterone sulfate (DHEAS) as assay standard) afte r C-18 reversed-phase extraction and LH-20 chromatography. Intra- and inter-assay coefficients of variation were 8.4% (15.0%) and 5.9% (17.6 %), respectively, at urinary 17-ketosteroid sulfate concentrations of 10.8 (1.9) nmol/ml. Recoveries observed in spiking and parallelism exp eriments varied between 88 and 102%. In a group of 4-year-old children showing a renal DHEAS output of less than 0.1 mu mol/d/l. 73 m(2) (me asured by radioimmunoassay) a relatively high median 17-ketosteroid su lfate excretion of 1.29 mu mol/d/l. 73 m(2) was found. Older children sulfates whereas excretion of DHEAS/d/1.73 m2 more than tripled from a ge group to age group. For children from 8 years onwards, adolescents, and adults, linear regression analysis indicated that urinary DHEAS e levations seem to contribute with a constant proportion of similar to 70% to the increments of total urinary 17-ketosteroid sulfates. These findings suggest that the attainment of such a constant relationship ( between the total 17-ketosteroid sulfates and their major component) f rom about 8 years of age onwards could represent the hormonal correlat e of the completion of the continuos zona reticularis in the adrenal g land (developing around this age from a focal reticularis zone).