Pathophysiological and clinical aspects of the insulin-like growth factors.

Except in acromegaly, where insulin-like growth factor I (IGF I) levels are elevated, only decreased IGF levels have been observed under pathophysiological conditions. These are hypopituitarism, Laron dwarfism, leprechaunism, liver disease, primary hypothyroidism, extrapancreatic tumor hypoglycemia and severe insulin deficiency in experimental animals. For most of these diseases the diagnostic value of IGF determinations is limited. IGF I determinations may serve as a useful additional diagnostic index in acromegaly and in the evaluation of successful operative and/or radiotherapy of this disease.