Urinary excretion of GH in healthy individuals and patients with acromegaly, hypopituitarism and dwarfism.

Urinary GH excretion reflects average plasma levels. Using a highly sensitive sandwich enzyme immunoassay we determined GH concentrations in the 24 h accumulated urine samples of 54 healthy persons (aged 1.5-90 years), 8 acromegalic patients, 4 acromegalic patients after enucleation of a GH-producing adenoma, 8 patients with partial hypopituitarism and in first morning urine and 12 h accumulated daytime urine of 4 healthy children and 3 children with growth failure. GH secretion is age-dependent, with high rates between ages 1 and 20 (ages 0-20 years: 10.4 ng/g creatinine +/- 6.3 vs age > 20-75 years: 3.1 ng/g creatinine +/- 1.6). An age-dependent increase in urinary GH is found in the pubertal age group (10 ng/24 h +/- 6.8 vs prepubertal group: 4.6 ng/24 h +/- 2.95). GH excretion of patients with acromegaly differs significantly from healthy subjects (72 ng/24 h +/- 49 vs 3.9 ng/24 h +/- 2.3). After a successful operation, acromegalic patients do not differ from the collective norm. Six of 8 patients with partial hypopituitarism show lower GH concentrations in urine than healthy subjects (1.2 ng/l +/- 0.2 vs 2.6 ng/l +/- 1.2), but daily GH output does not differ, since significantly more urine is then excreted. At night, healthy children secrete significantly more GH than during the day (night: 0.16 ng.kg-1 x (12 h)-1 +/- 0.02 vs day: 0.07 ng.kg-1 x (12 h)-1 +/- 0.03), while output is the same for GH-deficient children. Both groups have similar GH daytime output, but GH-deficient children have significantly less nocturnal output.(ABSTRACT TRUNCATED AT 250 WORDS)