Endocrine Abstracts

Hyperprolactinaemia is a common referral reason from primary and secondary care for contrast-enhanced pituitary magnetic resonance imaging (MRI). This retrospective study at University Hospitals of North Midlands, Stoke-on-Trent reviewed the records of new patients referred for pituitary MRI between 1 June 2021 and 31 May 2023 with hyperprolactinaemia as indication. 71 patients were identified. 82% of the cohort were women. Age ranged between 18-87 years; the majority were between 21-40 years (66%). 22 requests were from primary care, remaining 49 from hospital clinics. Indications for prolactin testing included menstrual irregularities (35%), infertility (22%), headache (18%), erectile dysfunction (14%), galactorrhoea (13%), antipsychotic monitoring (6%), and incidental finding (4%). 18 patients (25%) had a first prolactin of <500; 42 patients (58%) had a prolactin of 501-1000; 10 patients (14%) had 1001-5000 and 2 patients (3%) had >5000. 15 patients met the laboratory screening criteria for macroprolactin. 38 patients (54%) had repeat prolactin. 24/38 (63%) had normal repeat prolactin. Among the 24 patients with normal repeat prolactin, 23 (96%) had a normal pituitary gland, and one had a 2.5mm incidental pituitary cyst. 12 patients (17%) had pituitary adenoma (mean prolactin: 4,163); 7 (10%) macroadenoma and 5 (7%) microadenoma. Of these 12 patients, seven were treated as prolactinoma and received cabergoline (mean prolactin: 6,479). Cabergoline reduced prolactin in five patients, mean prolactin reducing to 480. In one patient, prolactin increased from 597 to 796 and one is awaiting post treatment prolactin. Two patients showed a reduction in adenoma size, two had a stable appearance and the remaining three are awaiting follow-up scans. Our data suggests that repeat prolactin testing can potentially reduce pituitary MRI requests for transient hyperprolactinaemia. Such requests add to the significant burden on radiology services. However, in those with persistently elevated prolactin, pituitary MRI is crucial for further evaluation and management.