STRATEGY FOR EXAMINATION OF GROWTH-HORMON E HYPERSECRETION

GH secretion is episodic in humans. Isolated plasma concentrations thu s cannot be used to diagnose excess secretion. Assays on GH secretion require repeat determinations of plasma levels over extended 24 h peri ods. In so-called conjunctive GH hypersecretion conditions (denutritio n, critical states), excessive GH secretion is associated with resista nce to this hormone, as indicated by a decrease in plasma IGF-I concen trations. In contrast, IGF-I concentrations are high and correlated wi th GH levels during permanent GH hypersecretion that occurs in acromeg aly. Testing for this disorder will vary according to the clinician's objectives.