The use of GH provocative tests to diagnose children with short stature continues to be a controversial issue. GH secretion is considered a continuum ranging from absent to normal secretion. When GH deficiency is severe, as in GH gene defects and craniopharyngiomas, there is a very important growth failure and absent or minimal GH response to stimulation tests. These situations could be used as standards to define total GH deficiency. However, partial GH deficiency also can show growth failure, but with variability of GH secretion on provocative tests. Moreover, several factors can influence GH secretion and GH-IGF axis. Determination of cutoff values in a non-physiological test to define normality is erroneous and can induce to error. Moreover, the lack of knowledge of normal values for different tests and assays in each clinical situation increases the difficulty to decide the treatment of a child with short stature based only on the results of a GH provocative tests. The considerations above do not mean that GH provocative tests are not important for diagnosis of short stature, but that the results of these tests should not be the final determinant of a clinical decision. They should be used in association with the clinical picture and other laboratory methods available to evaluate the hypothalamo-pituitary region and the GH-IGF axis. To reduce the risk of unnecessary treatment of a child with normal pituitary function and, on the other hand, to avoid delay or no-treatment of a child that could benefit with the use of recombinant human GH should be the principles to orient a medical decision.
GH; GH-IGF axis; GH deficiency; Provocative tests; Short stature
