Etiologies and Clinical Manifestations of Hyperprolactinemia in A Medical Center in Southern Taiwan

The aim of this study was to investigate the etiologies and clinical manifestations of hyperprolactinemia in a medical center. From May 1999 through October 1999, 140 consecutive patients with hyperprolactinemia were enrolled. Medical records of demographic data, presenting symptoms, departments visited, serum prolactin level, brief history, comprehensive drug history (drug name or classes of drug), pituitary imaging studies, and causes of hyperprolactinemia were analyzed. Of the 125 females patients studied, 53 ( 42% ) had menstrual problems, 41 ( 33% ) had galactorrhea, and 19 ( 15% ) were infertile. In contrast, epilepsy ( 11 patients, 73% ) was the leading symptom and cause of hyperprolactinemia in male patients. The etiologies of hyperprolactinemia included idiopathic hyperprolactinemia (46 patients, 32.9%), drug-induced hyperprolactinemia (33 patients, 23.6%), and pituitary tumors ( 28 patients, 20% ). Four of 33 ( 12% ) patients with drug-induced hyperprolactinemia had prolactin levels between 100 ng/mL and 200 ng/mL while another six ( 18% ) patients had prolactin levels above 200 ng/mL. Although the prolactin levels in the macroadenoma group seem higher than in the microadenoma group ( 169±33.4 ng/mL vs 89±15.6 ng/mL, p = 0.105 ), the difference was not statistically significant. Idiopathic hyperprolactinemia, drug-induced hyperprolactinemia, and pituitary tumors were the major causes of hyperprolactinemia. There were no significant differences in clinical manifestations among patients with different etiologies. High prolactin levels were not diagnostic of prolactinoma and serum prolactin levels were not predictive of tumor size. ( J Intern Med Taiwan 2004; 15: 19-24 )