Pituitary apoplexy and sudden blindness following the administration of gonadotrophin releasing hormone

GnRH agonist-associated pituitary apoplexy: a case series and review of the literature

PURPOSE

To examine the clinical presentation and longitudinal outcome of Pituitary Apoplexy (PA) after gonadotropin-releasing hormone agonist (GnRHa) in a series of patients and compare to prior reports.

METHODS

A retrospective chart review was performed on seven patients receiving GnRHa who developed PA. Prior reported cases were analyzed.

RESULTS

Six men (median age 72 years) with prostate cancer and one woman (aged 22 years) undergoing oocyte donation presented with PA between 1990 and 2020. Most presented with within 24 h of the first dose, but two developed PA 1 to 5 months after GnRHa initiation. The main clinical manifestations were headache (100%), nausea and vomiting (86%). While no patients had a previously known pituitary tumor, all had imaging demonstrating sellar mass and/or hemorrhage at presentation. Among those surgically treated (5/7), 80% (4/5) of patients had pathologic specimens that stained positive for gonadotropins; the remaining patient's pathologic specimen was necrotic. At the time of PA, the most common pituitary dysfunction was hypocortisolism. Central adrenal insufficiency and central hypothyroidism were reversible in a subset. Pituitary imaging remained stable.

CONCLUSIONS

This is the first report of a case series with PA after GnRHa administration with longitudinal follow-up. Although infrequent, PA can be life-threatening and should be suspected among patients receiving GnRHa, with or without a known pituitary adenoma, who develop acute headache, nausea and/or vomiting. Since hypopituitarism was reversible in a subset, ongoing pituitary function testing may be indicated.

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.

Pituitary tumor apoplexy

We review the etiology, investigations, management and outcomes of pituitary tumor apoplexy. Pituitary tumor apoplexy is a clinical syndrome which typically includes the acute onset of headache and/or visual disturbance, cranial nerve palsy and partial or complete endocrine dysfunction. It is associated with either infarction or hemorrhage of a pre-existing pituitary adenoma and is associated with significant morbidity and potential fatality. Not all patients will present with classic signs and symptoms, therefore it is pertinent to appreciate the clinical spectrum in which this condition can present.

Chorionic gonadotropin and its receptor are both expressed in human retina, possible implications in normal and pathological conditions

Extra-gonadal role of gonadotropins has been re-evaluated over the last 20 years. In addition to pituitary secretion of luteinizing hormone (LH) and follicle stimulating hormone (FSH), the CNS has been clearly identified as a source of hCG acting locally to influence behaviour. Here we demonstrated that human retina is producing this gonadotropin that acts as a neuroactive molecule. Müller glial and retinal pigmented epithelial (RPE) cells are producing hCG that may affects neighbour cells expressing its receptor, namely cone photoreceptors. It was previously described that amacrine and retinal ganglion (RGC) cells are targets of the gonadotropin releasing hormone that control the secretion of all gonadotropins. Therefore our findings suggest that a complex neuroendocrine circuit exists in the retina, involving hCG secreting cells (glial and RPE), hCG targets (photoreceptors) and hCG-release controlling cells (amacrine and RGC). The exact physiological functions of this circuit have still to be identified, but the proliferation of photoreceptor-derived tumor induced by hCG demonstrated the need to control this neuroendocrine loop.

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.

UK guidelines for the management of pituitary apoplexy

Classical pituitary apoplexy is a medical emergency and rapid replacement with hydrocortisone maybe life saving. It is a clinical syndrome characterized by the sudden onset of headache, vomiting, visual impairment and decreased consciousness caused by haemorrhage and/or infarction of the pituitary gland. It is associated with the sudden onset of headache accompanied or not by neurological symptoms involving the second, third, fourth and sixth cranial nerves. If diagnosed patients should be referred to a multidisciplinary team comprising, amongst others, a neurosurgeon and an endocrinologist. Apart from patients with worsening neurological symptoms in whom surgery is indicated, it is unclear currently for the majority of patients whether conservative or surgical management carries the best outcome. Post apoplexy, there needs to be careful monitoring for recurrence of tumour growth. It is suggested that further trials be carried out into the management of pituitary apoplexy to optimize treatment.

Pituitary tumor apoplexy: a review

Pituitary tumor apoplexy is an uncommon syndrome resulting often spontaneously from hemorrhage or infarction of a pre-existing pituitary adenoma. As the primary event involves the adenoma, the syndrome should be referred to as pituitary tumor apoplexy and not as pituitary apoplexy. The sudden increase in sellar contents compresses surrounding structures and portal vessels, resulting in sudden, severe headache, visual disturbances, and impairment in pituitary function. Initial management of patients with pituitary tumor apoplexy includes supportive therapy (intravenous fluids and corticosteroids), following which many patients exhibit clinical improvement. Because those patients can be effectively managed with supportive measures, many who remain clinically and neurologically unstable might benefit from urgent surgical decompression by an experienced neurosurgeon. All patients presenting with this syndrome require long-term follow-up to treat any residual tumor and/or pituitary dysfunction. Close interaction between members of the management team is necessary for optimal patients' outcome.

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.

Management of pituitary apoplexy

Pituitary apoplexy is a rare clinical syndrome caused by sudden haemorrhaging or infarction of the pituitary gland, generally within a pituitary adenoma. Headache of sudden and severe onset is the main symptom, associated with visual disturbances or ocular palsy. Signs of meningeal irritation or altered consciousness may complicate the diagnosis. Corticotropic deficiency (secondary adrenal failure) may be life-threatening if untreated. Computed tomography (CT) or magnetic resonance imaging (MRI) confirm the diagnosis by revealing a pituitary tumour with haemorrhagic and/or necrotic components: CT is most useful in the acute setting (24 - 48 h), MRI is useful for identifying blood components in the subacute setting (4 days to 1 month). Owing to the highly variable course of this syndrome and the limited individual experience, the optimal management of acute pituitary apoplexy is controversial. Some authors advocate early transphenoidal surgical decompression for all patients, whereas others adopt a more conservative approach for selected patients (those without visual acuity or field defects and with normal consciousness). Glucocorticoid treatment must always be initiated immediately, at a dose of hydrocortisone 50 mg every 6 h.

Subarachnoid haemorrhage: diagnosis, causes and management

The incidence of subarachnoid haemorrhage (SAH) is stable, at around six cases per 100 000 patient years. Any apparent decrease is attributable to a higher rate of CT scanning, by which other haemorrhagic conditions are excluded. Most patients are <60 years of age. Risk factors are the same as for stroke in general; genetic factors operate in only a minority. Case fatality is approximately 50% overall (including pre-hospital deaths) and one-third of survivors remain dependent. Sudden, explosive headache is a cardinal but non-specific feature in the diagnosis of SAH: in general practice, the cause is innocuous in nine out of 10 patients in whom this is the only symptom. CT scanning is mandatory in all, to be followed by (delayed) lumbar puncture if CT is negative. The cause of SAH is a ruptured aneurysm in 85% of cases, non-aneurysmal perimesencephalic haemorrhage (with excellent prognosis) in 10%, and a variety of rare conditions in 5%. Catheter angiography for detecting aneurysms is gradually being replaced by CT angiography. A poor clinical condition on admission may be caused by a remediable complication of the initial bleed or a recurrent haemorrhage in the form of intracranial haematoma, acute hydrocephalus or global brain ischaemia. Occlusion of the aneurysm effectively prevents rebleeding, but there is a dearth of controlled trials assessing the relative benefits of early operation (within 3 days) versus late operation (day 10-12), or that of endovascular treatment versus any operation. Antifibrinolytic drugs reduce the risk of rebleeding, but do not improve overall outcome. Measures of proven value in decreasing the risk of delayed cerebral ischaemia are a liberal supply of fluids, avoidance of antihypertensive drugs and administration of nimodipine. Once ischaemia has occurred, treatment regimens such as a combination of induced hypertension and hypervolaemia, or transluminal angioplasty, are plausible, but of unproven benefit.

Apoplexy of a pituitary macroadenoma with reversible third, fourth and sixth cranial nerve palsies following administration of hypothalamic releasing hormones: MR features

Pituitary apoplexy in patients with pituitary macroadenomas can occur either spontaneously or following various interventions. We present a case of a 71-year-old woman who developed third, fourth, and sixth cranial nerve palsies following administration of the four hypothalamic releasing hormones for routine preoperative testing of pituitary function. The MR examination showed interval tumor growth with impression of the floor of the third ventricle. There were also changes in signal intensity characteristics of the mass, suggestive of intratumoral bleeding. A transsphenoidal surgery with subtotal resection of the pituitary adenoma was performed. Microscopical examination revealed large areas of necrosis and blood surrounded by adenomatous tissue. Third, fourth, and sixth cranial nerve palsies completely resolved within 4 months. We conclude that MR imaging is useful in the demonstration of pituitary apoplexy following preoperative stimulation tests, but we suggest that these tests should be abandoned in patients with pituitary macroadenomas.

Gonadotropin-releasing hormone-induced partial empty sella clinically mimicking pituitary apoplexy in a woman with a suspected non-secreting macroadenoma

Pituitary apoplexy has been reported as a rare complication of dynamic testing used for the study of pituitary functional reserve. In 1993, a diagnosis of non-secreting macroadenoma with moderate functional hyperprolactinaemia was made in a 43-year-old woman. Soon after the start of therapy with bromocriptine up to 5 mg/die, the patient complained of nausea and postural hypotension. As the symptoms persisted even when the dose was reduced to 2.5 mg/die, the patient was transferred to therapy with quinagolide at the dosage of 37.5 microg/die. PRL levels quickly normalized (range 1.4-5.7 ng/ml) as well as menstrual cycles, and no side-effect was reported. In 1995 a sellar magnetic resonance imaging (MRI) showed no shrinkage of the known macroadenoma. In 1996, few hours after a gonadotropin-releasing-hormone (GnRH) test, which showed normal LH and FSH response and with baseline PRL levels in the normal range, the patient started complaining of severe frontal headache, nausea and vomiting. No gross visual defects were present. An emergency computed tomography (CT) showed no evident hemorrhagic infarction in the macroadenoma. The symptoms completely resolved in few days with steroidal and antiemetic therapy. A new MRI performed in 1998 showed a partial empty sella and PRL levels were in the normal range under dopaminergic treatment. The pituitary functional reserve proved normal on dynamic testing. The temporal association between the onset of symptoms and the GnRH test strongly suggests an association between the two events. No evident signs of pituitary apoplexy (either on emergency CT or hormonal evaluation) were detected. The authors suggest that GnRH can cause severe side-effects that mimic pituitary apoplexy without related morphological evidence and that, in our particular case, it can have caused the gradual disappearance of the non-secreting macroadenoma. Moreover, a causal role of the chronic dopaminergic treatment cannot be completely ruled out.

Pituitary apoplexy probably due to TRH and GnRH stimulation tests in a patient with acromegaly

Pituitary apoplexy is the most serious and life-threatening complication of pituitary adenomas. Most of the cases occur spontaneously but it may occur also after a number of events such as the pituitary stimulation tests. We report a case of acromegaly due to a giant pituitary adenoma in which pituitary apoplexy developed 88 hours after TRH/GnRH stimulation test. The patient had severe headaches, nausea, vomiting, visual disturbance and mental alteration and the computed tomography (CT) scans revealed intratumoral and intraventricular bleeding. The pituitary mass was removed by transsphenoidal approach. The patient developed pneumonia and died on the 9th postoperative day. Pituitary apoplexy was confirmed at surgery and on histological examination. Immunohistochemical staining was positive for GH and PRL. This case indicates that pituitary apoplexy may develop several days after TRH/GnRH stimulation test.

Pituitary apoplexy of a gonadotroph adenoma following gonadotrophin releasing hormone agonist therapy for prostatic cancer

Treatment of prostatic cancer with GnRH agonist is a medical alternative to surgical castration, although hyperstimulation of the tumor can occur. We describe an unusual unwanted effect of such a treatment which unmasked a clinically silent gonadotroph adenoma. A 62-year-old man developed after the first injection of leuprorelin-depot a sudden intracranial hypertension, which was related to apoplexy of an unknown pituitary adenoma. Its gonadotroph origin was recognized after surgery by immunocytochemistry. Retrospectively, the tumor was shown to secrete in vivo both FSH and LH when on therapy with the agonist, demonstrating the lack of desensitization. Testosterone levels were also markedly and sustainly high when on therapy, a particularly unwanted effect in prostatic cancer. As gonadotroph adenomas occur in men in the same age group as prostatic cancer, the question is raised whether hormonal testing and pituitary imaging should be performed before starting a therapy with GnRH agonist in men.

Pituitary Tumor Apoplexy: Pathophysiology, Clinical Manifestations, and Management

Pituitary tumor apoplexy represents a rare clinical syndrome caused by hemorrhagic infarction of an existing, often previously unrecognized, large adenoma. We present our approach and experience in the field, and we provide a summary of pertinent published literature addressing diagnosis, management, and pathophysiology of the clinical manifestations of pituitary tumor apoplexy. Although many precipitating factors are known, most episodes occur spontaneously and present clinically with relatively sudden onset of severe headache, visual field defects, and ophthalmoplegia. Either computed tomography (nonenhanced and enhanced) or magnetic resonance imaging in a symptomatic patient can define pertinent anatomical changes and aid in establishing diagnosis. Immediate treatment with corticosteroids is necessary. Patients with the mild form of the syndrome respond quickly to steroids and can be managed conservatively with continued glucocorticoid therapy. Most patients with persistent neural deficits require urgent transsphenoidal decompression. Unless surgery is delayed, results of transsphenoidal decompression are usually very good, and improvements in neurological symptoms and endocrine function are noted within hours to days of the procedure. Patients need to be closely followed up after the episode because a large number continue to have residual tumor requiring additional therapy, or they have pituitary hormone abnormalities that need treatment. Close interaction between neurosurgeons and endocrinologists in the management of patients with pituitary tumor apoplexy is essential for optimal outcome.

Clomiphene-induced pituitary apoplexy in a patient with acromegaly

We describe the case of an acromegalic woman with primary infertility who was treated with clomiphene, and subsequently developed pituitary apoplexy.

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.