Assessment of prolactin release in pituitary dwarfism with the sulpiride test

We report here the results obtained with a new test of prolactin (PRL) release in six normal pre-pubertal boys, eleven children with short stature of non-pituitary origin and in thirteen pituitary dwarfs. The test consists of the administration of 100 mg of sulpiride i.m. and the measurement of PRL in serum samples up to 120 min after injection. Baseline PRL concentrations were not clearly different in the three groups. After sulpiride a marked increase (3--10 times over control values) in PRL was noted in all normal and short children without pituitary disease. A complete failure of response was observed in ten of the thirteen pituitary dwarfs. It is concluded that sulpiride has considerable potential in the differential diagnosis of children with stunted growth.