An audit of the diagnostic usefulness of PRL and TSH responses to domperidone and high resolution magnetic resonance imaging of the pituitary in the evaluation of hyperprolactinaemia

Abstract

The majority of patients with a normal dynamic response of PRL to domperidone had a normal or near normal pituitary MRI scan. In the two cases where an abnormality was detected it could have been an incidental microadenoma or cyst, thus suggesting that pituitary scanning could normally be omitted in patients whose PRL response to domperidone is normal (24% of our total). The group of patients with an abnormal dynamic response of PRL to domperidone was not generally amenable to further diagnostic refinement by considering the degree of hyperprolactinaemia or the TSH response to domperidone because of overlap of these parameters between the diagnostic subgroups. Therefore any degree of hyperprolactinaemia associated with a blunted PRL response to domperidone warrants pituitary imaging.