Assessment of growth hormone status in acromegaly: what biochemical markers to measure and how?

Various studies have evaluated the usefulness of measuring insulin-like gro wth factor I (IGF-I) and IGF-binding proteins, compared with growth hormone (GH), in the diagnosis and follow-up of patients with acromegaly. The clin ical use of recently developed, highly sensitive GH assays has improved our understanding of the secretion of GH at very low concentrations. Studies e xamining the GH nadir after oral glucose administration in healthy adults s uggest that GH values should be suppressed to no more than 0.14 mu g/l afte r oral glucose administration. The highly sensitive GH assays are now being used in the diagnosis of patients with acromegaly and in post-treatment fo llow-up. In addition, the use of IGF-I immunoassays has confirmed that seru m IGF-I level is a reliable and useful biochemical marker for determining G H excess. The widespread use of highly sensitive, carefully validated assay s offers accurate and reproducible biochemical information that will help i n the overall clinical management of patients with acromegaly, including th e monitoring of disease remission, disease cure and treatment titration reg imen, as well as the early recognition of patients with residual disease. ( C) 2000 Harcourt Publishers Ltd.