Severe hyperprolactinemia associated with internal carotid artery aneurysm: differential diagnosis between prolactinoma and hypothalamic-pituitary disconnection

Abstract

sellar and parasellar masses blocking inhibitory hypothalamic dopaminergic tonus can produce hyperprolactinemia. one of these conditions, seldom reported, is internal carotid artery aneurysm causing pituitary stalk compression and hyperprolactinemia, the majority of which is related to small increases in serum prolactin levels. the aim of this study is to report the case of a patient with an internal carotid aneurysm and severe hiperprolactinemia. A 72 years old female patient, on oncology follow-up for clinically controlled cervical carcinoma, was evaluated due to worsening chronic headaches. during the investigation, computed tomography and magnetic resonance imaging (Mri) showed a sellar mass associated with high prolactin level (1.403 µg/l) that initially was considered a macroprolactinoma, and treated with bromocriptine. However, subsequent pituitary Mri suggested an internal carotid aneurysm, which was confirmed by an angioresonance imaging of cerebral vessels. on low bromocriptine dose (1.25 mg/day), there was a prompt normalization of prolactin levels with a great increase (> 600 µg/l) after withdrawal, which was confirmed several times, suggesting HPd. We report a patient with internal carotid artery aneurysm with severe hyperprolactinemia never reported before in patients with HPd, and the need for a differential diagnosis with macroprolactinomas even considering high prolactin levels. Massas selares e parasselares podem produzir hiperprolactinemia por bloquear o tônus inibitório hipotalâmico de dopamina. uma destas condições, raramente reportada, é o aneurisma de artéria carótida interna causando compressão da haste hipofisária e hiperprolactinemia, a maioria com pequenas elevações da prolactina. o objetivo deste estudo é descrever o caso de uma paciente com aneurisma de carótida interna e grave hiperprolactinemia. Paciente feminina, 72 anos, em acompanhamento oncológico por carcinoma de colo de útero clinicamente controlado, avaliada por causa da piora de cefaléia crônica. durante investigação, tomografia computadorizada e ressonância magnética (rM) de hipófise mostraram massa selar associada com altos níveis de prolactina (1.403 µg/l), sendo avaliado como macroprolactinoma e tratado com bromocriptina. entretanto, rM subseqüente sugeriu aneurisma de carótida interna que foi confirmado por angiorressonância de vasos cerebrais. em uso de baixas doses de bromocriptina (1,25 mg/dia), houve pronta normalização da prolactina com grande elevação (> 600 µg/l) após a retirada do medicamento, sendo confirmado por várias vezes sugerindo dHH. reporta-se uma paciente com aneurisma de artéria carótida interna com grave hiperprolactinemia, nunca descrita anteriormente em pacientes com dHH, e a necessidade do diagnóstico diferencial com macroprolactinoma, mesmo considerando altos níveis de prolactina. Descritores: Hiperprolactinemia; Aneurisma de artéria carótida interna; desconexão hipotálamo-hipofisária; Prolactinoma; diagnóstico diferencial de tumor hipofisário

Challenges and pitfalls in the diagnosis of hyperprolactinemia

“…Previously, there have been reports of a NFPA with PRL of 662 ng/mL and an intrasellar plasmacytoma with suprasellar extension and PRL levels of 504 ng/mL (86,87). More recently, very high PRL levels (1,403 ng/mL) were also reported in a patient with a giant aneurysm of the internal carotid artery (88).…”

Concurrent Panhypopituitarism and Hyperprolactinemia Due to a Giant Internal Carotid Aneurysm Revealed by Thyroid Hormone Withdrawal During Follow-Up Management of Thyroid Cancer

“…Previously, GICAA was found to be associated with both hypopituitarism and hyperprolactinemia (6). In fact, a prolactin concentration of 1,403 ng/mL has been documented in GICAA without concurrent pituitary tumor (7). Presumably, prolactin was elevated secondary to pituitary stalk compression.…”

Persistence of intrasellar trigeminal artery and simultaneous pituitary adenoma: description of two cases and their importance for the differential diagnosis of sellar lesions

“…There are reports of aneurisms that mimic pituitary adenomas by causing hormonal changes, such as hypopituitarism and hyperprolactinemia, mostly due to mass effect (hypothalamic-pituitary disconnect) (13).…”