Pituitary apoplexy after stimulation tests

Apoplexy in sporadic pituitary adenomas: a single referral center experience and AIP mutation analysis

Objective

To analyze the clinical, laboratory, and radiological findings and management of patients with clinical pituitary apoplexy and to screen for aryl hydrocarbon receptor-interacting protein (AIP) mutations.

Methods

The clinical findings were collected from the medical records of consecutive sporadic pituitary adenoma patients with clinical apoplexy. Possible precipitating factors, laboratory data, magnetic resonance imaging (MRI) findings and treatment were also analyzed. Peripheral blood samples were obtained for DNA extraction from leukocytes, and the entire AIP coding region was sequenced.

Results

Thirty-five patients with pituitary adenoma were included, and 23 (67%) had non-functioning pituitary adenomas. Headache was observed in 31 (89%) patients. No clear precipitating factor was identified. Hypopituitarism was observed in 14 (40%) patients. MRI from 20 patients was analyzed, and 10 (50%) maintained a hyperintense signal in MRI performed more than three weeks after pituitary apoplexy (PA). Surgery was performed in ten (28%) patients, and 25 (72%) were treated conservatively with good outcomes. No AIP mutation was found in this cohort.

Conclusion

Patients with stable neuroophthalmological impairments can be treated conservatively if no significant visual loss is present. Our radiological findings suggest that hematoma absorption lasts more than that observed in other parts of the brain. Additionally, our study suggests no benefits of AIP mutation screening in sporadic patients with apoplexy.

Multidisciplinary Management of Pituitary Apoplexy

Pituitary apoplexy is a rare clinical syndrome due to ischemic or haemorrhagic necrosis of the pituitary gland which complicates 2-12% of pituitary tumours, especially nonfunctioning adenomas. In many cases, it results in severe neurological, ophthalmological, and endocrinological consequences and may require prompt surgical decompression. Pituitary apoplexy represents a rare medical emergency that necessitates a multidisciplinary approach. Modalities of treatment and times of intervention are still largely debated. Therefore, the management of patients with pituitary apoplexy is often empirically individualized and clinical outcome is inevitably related to the multidisciplinary team's skills and experience. This review aims to highlight the importance of a multidisciplinary approach in the management of pituitary apoplexy and to discuss modalities of presentation, treatment, and times of intervention.

Pituitary Apoplexy

Pituitary apoplexy, a rare clinical syndrome secondary to abrupt hemorrhage or infarction, complicates 2%-12% of pituitary adenomas, especially nonfunctioning tumors. Headache of sudden and severe onset is the main symptom, sometimes associated with visual disturbances or ocular palsy. Signs of meningeal irritation or altered consciousness may complicate the diagnosis. Precipitating factors (increase in intracranial pressure, arterial hypertension, major surgery, anticoagulant therapy or dynamic testing, etc) may be identified. Corticotropic deficiency with adrenal insufficiency may be life threatening if left untreated. Computed tomography or magnetic resonance imaging confirms the diagnosis by revealing a pituitary tumor with hemorrhagic and/or necrotic components. Formerly considered a neurosurgical emergency, pituitary apoplexy always used to be treated surgically. Nowadays, conservative management is increasingly used in selected patients (those without important visual acuity or field defects and with normal consciousness), because successive publications give converging evidence that a wait-and-see approach may also provide excellent outcomes in terms of oculomotor palsy, pituitary function and subsequent tumor growth. However, it must be kept in mind that studies comparing surgical approach and conservative management were retrospective and not controlled.

Apoplexy of pituitary adenomas: the perfect storm

OBJECT

Pituitary adenomas occasionally undergo infarction, apoplexy, which often destroys much of the tumor. It is well known that apoplexy can be precipitated by several acute factors, including cardiac surgery, other types of surgery, trauma, insulin infusion, and stimulation with administration of hypothalamic releasing factors.

METHODS

The prior focus on mechanisms underlying pituitary apoplexy has been on these acute events. Less attention has been given to the endogenous features of pituitary tumors that make them susceptible to spontaneous infarction, despite that most pituitary apoplexy occurs in the absence of a recognized precipitating event. The authors examine intrinsic features of pituitary adenomas that render them vulnerable to apoplexy-features such as high metabolic demand, paucity of angiogenesis, and sparse vascularity, qualities that have previously not been linked with apoplexy-and argue that it is these features of adenomas that underlie their susceptibility to spontaneous infarction. The sensitivity of freshly cultured pituitary adenomas to hypoglycemia is assessed.

RESULTS

Adenomas have high metabolic demand, limited angiogenesis, and reduced vessel density compared with the normal gland. Pituitary adenoma cells do not survive in the presence of reduced or absent concentrations of glucose.

CONCLUSIONS

The authors propose that the frequent ischemic infarction of pituitary adenomas is the product of intrinsic features of these tumors. These endogenous qualities create a tenuous balance between high metabolic demand and marginal tissue perfusion. Thus, the tumor is vulnerable to spontaneous infarction or to acute ischemia by any event that acutely alters the balance between tumor perfusion and tumor metabolism, events such as acute systemic hypotension, abruptly decreased supply of nutrients, hypoglycemia with insulin administration, or increase in the tumor's metabolic demand due to administration of hypothalamic releasing factors. It may be possible to take advantage of these intrinsic features of pituitary adenomas by using aspects of this vulnerability for development of new approaches for treatment.

Pituitary apoplexy associated with endocrine stimulation test: endocrine stimulation test, treatment, and outcome

Pituitary apoplexy is a rare clinical syndrome attributable to hemorrhage or hemorrhagic infarction of pituitary tumors or pituitary glands. The features of pituitary apoplexy associated with the endocrine stimulation test remain to be elucidated and the importance of surgical treatment has not been discussed enough. We report two rare patients who were treated successfully by endoscopic endonasal transsphenoidal surgery within several hours after onset of pituitary apoplexy associated with the endocrine stimulation test. Their postoperative course was uneventful. We reviewed earlier reports on this clinical entity, document its features especially as related to the endocrine stimulation test, discuss the significance of immediate surgical treatment, and present our treatment outcomes. Performing only conservative treatment is not recommended. We suggest that the necessity of endocrine stimulation test should be assessed on a case-by-case basis and in patients subjected to the test, and neurosurgical support should be sought.

Pituitary apoplexy

Pituitary apoplexy is rare endocrine emergency which can occur due to infarction or haemorrhage of pituitary gland. This disorder most often involves a pituitary adenoma. Occasionally it may be the first manifestation of an underlying adenoma. There is conflicting data regarding which type of pituitary adenoma is prone for apoplexy. Some studies showed predominance of non-functional adenomas while some other studies showed a higher prevalence in functioning adenomas amongst which prolactinoma have the highest risk. Although pituitary apoplexy can occur without any precipitating factor in most cases, there are some well recognizable risk factors such as hypertension, medications, major surgeries, coagulopathies either primary or following medications or infection, head injury, radiation or dynamic testing of the pituitary. Patients usually present with headache, vomiting, altered sensorium, visual defect and/or endocrine dysfunction. Hemodynamic instability may be result from adrenocorticotrophic hormone deficiency. Imaging with either CT scan or MRI should be performed in suspected cases. Intravenous fluid and hydrocortisone should be administered after collection of sample for baseline hormonal evaluation. Earlier studies used to advocate urgent decompression of the lesion but more recent studies favor conservative approach for most cases with surgery reserved for those with deteriorating level of consciousness or increasing visual defect. The visual and endocrine outcomes are almost similar with either surgery or conservative management. Once the acute phase is over, patient should be re-evaluated for hormonal deficiencies.

Clinical relevance of precipitating factors in pituitary apoplexy

OBJECTIVE

The pathogenesis of pituitary apoplexy and the role of precipitating factors in pituitary apoplexy are poorly understood. Most of the published cases are in the form of case reports. We assessed the presumed precipitating factors in a series of patients treated surgically for pituitary apoplexy and reviewed the contemporary published literature.

METHOD

Thirty-eight consecutive patients with pituitary apoplexy were treated surgically by the Department of Neurosurgery at the University of Virginia, Charlottesville, VA, between January 1996 and March 2006. Their medical records were retrospectively reviewed. Contemporary published cases from 1990 to 2006 were also reviewed.

RESULTS

Nine patients (24%) were identified as having precipitating factors for pituitary apoplexy. The factors identified were coronary artery surgery (two patients), other major surgery (two patients), pregnancy (two patients), gamma knife irradiation, anticoagulant therapy, and coagulopathy secondary to liver failure. The presentation, histology, and outcome were compared between those patients with a precipitating factor and those in whom none was identified. A review of the published literature showed that coronary artery surgery, pituitary stimulation, and coagulopathy were the most common precipitating factors.

CONCLUSION

A minority of patients with pituitary apoplexy will have precipitating factors. The majority of patients with precipitating factors will have histopathology showing hemorrhagic infarction or hemorrhage. The most common precipitating factors are pituitary stimulation, surgery, particularly coronary artery surgery, and coagulopathy. Caution in doing endocrine investigation, surgery, or anticoagulation in patients with a known pituitary tumor is advised. Patients with no diagnosed pituitary tumor but with a known precipitating factor who have neuro-ophthalmological deterioration or endocrine failure should undergo prompt magnetic resonance image scans and endocrine investigation and endocrine replacement as indicated.

Gonadotropin-releasing hormone agonist-induced pituitary apoplexy in treatment of prostate cancer: case report and review of literature

OBJECTIVE

To describe a case and review the literature on the rare complication of pituitary apoplexy after administration of a gonadotropin-releasing hormone agonist (GnRHa) for treatment of patients with prostate cancer.

METHODS

We present a detailed case report of a patient with immediate signs of pituitary apoplexy after receiving a GnRHa and review the 6 previously reported cases in the literature. A 60-year-old man presented to a local hospital with severe headache, nausea, vomiting, and diplopia. Prostate cancer had recently been diagnosed, and he had received his first dose of a GnRHa 4 hours before this presentation. On physical examination, he was confused and had ptosis of the left eye. A head computed tomographic scan without contrast enhancement showed soft tissue filling the sella, without intracranial hemorrhage or mass effect. He was discharged with the diagnosis of viral meningitis. Three weeks later, he presented again with severe headache and diplopia. He had confusion, lethargy, disorientation, a blood pressure of 88/64 mm Hg, and left cranial nerve III, IV, and VI paralysis. Magnetic resonance imaging of the brain revealed an enhancing pituitary mass with hemorrhage extending to the optic chiasm, consistent with pituitary apoplexy. Laboratory results were consistent with panhypopituitarism. Surgical excision revealed a necrotic pituitary macroadenoma with hemorrhage. Tumor immunohistochemical staining was positive only for luteinizing hormone.

CONCLUSION

We describe a rare adverse effect of GnRHa therapy, which unmasked a gonadotropin-secreting pituitary macroadenoma. This case adds to the 6 previously reported cases of GnRHa administration inducing pituitary apoplexy in men with prostate cancer.

Apoplexy accompanying pituitary adenoma as a complication of preoperative anterior pituitary function tests

Pituitary apoplexy occurs as a very rare complication of the pituitary function test. We have experienced two cases of pituitary apoplexy following anterior pituitary function tests for preoperative assessment: a triple bolus test and a TRH test. To elucidate such a rare complication, we outline our two cases and review 28 cases from the literature. The clinical characteristics, etiology, pathophysiology, and diagnostic and therapeutic implications are also discussed. The combined data suggest that pituitary function tests have the potential to precipitate pituitary apoplexy, and its manifestations range from a clinically benign event to a catastrophic presentation with permanent neurological deficits or even death, although most patients may fortunately have a good outcome. We suggest that the pituitary function test should not be done as a routine test, and when such a test is planned, the patient should be observed with caution for any symptomatic changes for at least 2 hours following the test for appropriate treatment. Further, MRI, especially enhanced studies, may provide an earlier diagnosis of the pituitary apoplexy since CT scan images often fail to demonstrate either density changes or obvious enlargement of the pituitary adenoma at the acute stage.

Pituitary Apoplexy

OBJECTIVE:

Pituitary apoplexy is a rare yet potentially fatal disease. We reviewed the combined experience of the University of Virginia in Charlottesville, VA, and Groote Schuur Hospital, University of Cape Town, South Africa, with 62 cases of pituitary apoplexy.

METHODS:

An Internet web site with a database was constructed, and the records of 62 patients were entered into the database from both institutions and then systematically analyzed.

RESULTS:

The average age of patients was 51.1 years; 60% were male, and the average length of follow-up was 55 months. The average time of presentation was 14.2 days after the ictus, and 81% had no previous history of pituitary tumor. Headache was the most common presenting symptom (87%). Diminished visual acuity was found in 56% of patients, bitemporal hemianopia in 34%, ocular palsies in 45%, and diminished level of consciousness in 13%. Seventy-three percent of the patients had laboratory evidence of hypopituitarism, and 8% had diabetes insipidus. Fifty-eight patients underwent surgery, 3 were treated conservatively, and 1 died before intervention. Histological examination revealed hemorrhagic infarction in 47%, simple infarction in 40%, and frank hemorrhage in 8%. Seventy-nine percent had a good outcome, although 83% required subsequent hormonal replacement therapy.

CONCLUSION:

Pituitary apoplexy is often misdiagnosed because the majority of patients have undetected pituitary adenomas, and the presentation is often mistaken for subarachnoid hemorrhage. Most cases of pituitary apoplexy occur spontaneously, although precipitating factors have been suggested. Magnetic resonance imaging is the imaging modality of choice. Treatment includes high-dose corticosteroid administration and surgery. Transsphenoidal surgery is indicated in patients with diminished levels of consciousness, hypothalamic dysfunction, and visual deterioration. Conservative management for patients with isolated cranial nerve palsies has been advocated but remains controversial.

Pituitary tumor apoplexy: characteristics, treatment, and outcomes

Pituitary tumor apoplexy is an uncommon event heralded by abrupt onset of severe headache, restriction of visual fields, deterioration of visual acuity, and weakness of ocular motility frequently coupled with clinical indications of decreased endocrine function. Hemorrhage into or necrosis of a preexisting sellar mass, usually a pituitary macroadenoma, produces an expansion of sellar contents. Compression of adjacent structures elicits the variable expression of symptoms referable to displacement of the optic nerves and chiasm and impingement of the third, fourth, and sixth cranial nerves. Damage to or destruction of the anterior pituitary leads to multiple acute and/or chronic hormone deficiencies in many patients. Medical management may be used in rare cases in which the signs and symptoms are mild and restricted to meningismus or ophthalmoplegia deemed to be stable. In patients with visual or oculomotor lability or an altered level of consciousness, expeditious surgical decompression, accomplished most commonly through a transsphenoidal approach, should be performed to save life and vision and to optimize the chance of regaining or maintaining pituitary function.