91 URINARY GROWTH HORMONE (GH) – CLINICAL APPLICATION

Abstract

A radiometric assay for GH was applied to unprocessed urine (technical details previously described). A significant correlation between plasma profiles and urinary GH excretion has been found (i.e. 24 h plasma integrated concentrations (IC) to urine pg/24 h, r = 0.45. Plasma IC 24 h to night urine GH/creatinine 0.69, night plasma IC to night urine 0.58, for all correlations N = 40). In 155 24 h-urines of “normal” children (partly referred for suspected growth problems), a mean GH-excretion of 6.2 ± 6.5 ng/24 h (median 4.1, P. 10 1.3, P. 90 13.6) has been found. No clear relation was found to chronological age, bone age or puberty ratings. 10 patients with “precocious puberty” (5 idiopathic, 5 treated CAH) had a mean excretion of 9.7 ± 5.4 (median 8.4, P. 10 4.6, P. 90 19). In active acromegaly, the values varied from 73 to 500 ng/24 h. Patients with “complete” (N = 9) and “partial” (N = 7) GH-deficiency had a mean (median) excretion of 0.79 (0.75) and 3.3 (1.8) ng/24 h off therapy. The values increased to 6.2 (3.8) and 11.3 (10.5) ng/24 h during therapy (2 IU daily s.c). Before more conclusions can be drawn, the important intraindividual variation of GH-excretion has to be considered. Nevertheless, urinary GH mirrors an actual GH-production over a set time and can be applied to clinical states with suspected “abnormal” GH-production or for therapy survey.