Unusual association of a pituitary adenoma and a neurological emergency: case report and diagnostic steps

Abstract

A 44-year-old female patient was admitted to the Emergency Department with a 2-day complaint of severe headache in the left frontal region. Her menstrual and pathological history was uneventful. Since 25 years she had been suffering from recurrent headache episodes with vomiting; in the last few years she had been taking oral estroprogestin contraceptives, with a concomitant symptom relief regarding frequency and severity. The latest attack had begun insidiously and was described as not different from the usual pattern; no features suggesting raised intracranial pressure, such as worsening at night or with the recumbent position, were reported. Incidentally, the patient reported the recent appearance of galactorrhea and discovery of elevated PRL serum concentrations (3,952 pmol/L, n.v.\1,100 pmol/L = 24.2 ng/mL). Finding on emergency computerized tomography (CT) imaging was a roundish isodense sellar mass; a presumptive diagnosis of pituitary adenoma was made.The patient was admitted to our Department of Internal Medicine. She appeared alert and attentive, orientated but suffering from intense pulsatile headache with nausea, only temporarily relieved by tramadole and ketorolac i.v. The endocrinological work-up disclosed serum PRL levels 2,486 pmol/L and undetectable gonadotropins compatible with the assumption of estroprogestin pill, stopped at admission; the patient was not assuming other drugs potentially responsible of hyperprolactinemia. The possibility of artifactually low values due to the ''hook effect'' was excluded using a 1:100 dilution of serum; the search for macroprolactinemia yielded negative results. Thyroid function was normal (TSH 2 mU/L; free thyroxine 14 pmol/L; free triiodothyronine 4.8 pmol/L) as well as corticotropin plasma concentration (4.8 pmol/L) and adrenal response to a low-dose ACTH test (1 lg), with cortisol concentration 364 nmol/L in basal conditions and 588 nmol/L after stimulation.The neurological examination did not show evidence of focal deficits or nuchal rigidity; speech was normal, tendon reflexes were symmetric and the plantar reflex was bilaterally in flexion. Fundus oculi examination revealed papilledema. Chest and abdominal examination was unremarkable.Contrast enhancement magnetic resonance imaging (MRI) of the sellar region (Fig. 1) showed a large wellcircumscribed dumbbell-shaped sellar and suprasellar mass, which involved the pituitary gland, dislocated the infundibular stalk on the left, abutted the optic chiasm and eroded into the sphenoid sinus. Hypothesizing a macroprolactinoma, a trial with cabergoline (0.5 mg twice a