Pituitary apoplexy after pituitary function test: a report of two cases and review of the literature.
BACKGROUND
Although most of pituitary apoplexy occur spontaneously, some precipitating factors have been reported. We experienced two cases of pituitary apoplexy after a pituitary function test.


METHODS
In order to clarify the causal relation between the pituitary function test and apoplexy, we presented our two cases and reviewed 20 cases in the literature.


RESULTS
(Case 1) A 48-year-old man with a pituitary macroadenoma received an injection of 500 micrograms thyrotropin-releasing hormone (TRH), 100 micrograms gonadotropin-releasing hormone (GnRH), and 0.1U/kg insulin as a preoperative test of pituitary function. Fifteen minutes later, he complained of diminished vision and headache. (Case 2) A 54-year-old man with a large cystic adenoma had an administration of 500 micrograms TRH and 100 micrograms GnRH. Ten minutes later, he complained of blurring of his left eye and headache. Although, in both cases, CT scans showed neither intratumoral hemorrhage nor infarction, the surgical specimen showed necrotic and hemorrhagic adenoma. The patients made excellent clinical recoveries after surgical decompression. Twenty-two reports including our two cases were reviewed. In 15 cases (68%), TRH was associated with apoplectic events and seemed to be the agent most likely to have an etiologic role because of its vasoactive properties. Eighteen patients (82%) had pituitary macroadenomas with suprasellar extension. In 72% of 18 surgical cases, some recovery of visual function was obtained.


CONCLUSIONS
An apparent relationship between the test and the apoplectic events raises the possibility of the development of pituitary apoplexy after a pituitary function test. Unless there is a specific indication, pituitary function test should be avoided especially in patients with a large pituitary tumor.
Masago
A
A
Department of Neurosurgery, Nagoya City University Medical School, Japan.
Ueda
Y
Y
Kanai
H
H
Nagai
H
H
Umemura
S
S
D000236:Adenoma / Q000175:diagnosis; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010899:Pituitary Apoplexy / Q000175:diagnosis / Q000209:etiology*; D010901:Pituitary Function Tests / Q000009:adverse effects*; D010911:Pituitary Neoplasms / Q000175:diagnosis