Endocrine Abstracts

JOINT2487

Introduction: Hyperprolactinemia is a common reason of referral to endocrinology outpatient clinics. This condition may be due to physiological, pharmacological or pathological causes. After ruling out some of them, many studies suggest performing a serial prolactin measurement to eliminate stress hyperprolactinemia, and then continuing to study those who truly present altered prolactin values. Objective: to evaluate the subsequent effectiveness of serial prolactin measurement in the detection of pituitary lesions.

Materials and Methods: Descriptive study of 53 patients who underwent serial prolactin measurements between the years 2023-24 in follow-up in our clinics. Demographic (sex, age), analytical (basal prolactin, at 20 and 40 minutes) and radiological (magnetic resonance imaging (MRI) of the sella turcica and the presence of a lesion there) variables were collected. Regarding the measurement, a peripheral intravenous line was inserted and a baseline, at 20 and at 40 minutes value was taken. It was established that prolactin was elevated above 20 (men) or 25 (women). The statistical analysis was performed with the IBM SPSS v.25 programme (Statistical significance P < 0.05).

Results: 53 patients were analysed, 83% of whom were women with a mean age of 29.9 ± 12.6 years. 73.6% and 77.4% of patients showed normal prolactin levels at 20 and 40 minutes, respectively. Basal and 20-minute prolactin, basal and 40-minute prolactin and basal and 20 and 40-minute prolactin means difference were 4.1 ± 6.3, 6.4 ± 10.1, and 2.2 ± 5.7, all of which were statistically significant. All patients with elevated prolactin levels at 40 minutes underwent sella turcica MRI, and lesions were observed in 58.3% of them.

Conclusion: In most cases, normalisation of prolactin levels is observed when serial measurements are performed at 20 and 40 minutes. In addition, a statistically significant difference is identified between the basal prolactin values and those obtained in subsequent measurements. Also, in most patients with an altered prolactin value at 40 minutes, the presence of a pituitary MRI lesion is observed. This supports the usefulness of serial prolactin measurement, not only to rule out stress hyperprolactinemia, but also to focus the diagnostic procedure on those patients with true hyperprolactinemia.