Gonadotropin-releasing hormone (GnRH) agonists, currently used in the treatment of advanced prostate cancer, have been described as a rare cause of pituitary apoplexy, a potentially life-threatening clinical condition. We report the case of a 69-year-old man with a known pituitary macroadenoma who was diagnosed with prostate cancer and started treatment with GnRH agonist leuprorelin (other hormones were not tested before treatment). Few minutes after drug administration, the patient presented with acute-onset severe headache, followed by left eye ptosis, diplopia and vomiting. Pituitary MRI revealed tumor enlargement and T1-hyperintense signal, compatible with recent bleeding sellar content. Laboratory endocrine workup was significant for low total testosterone. The patient was managed conservatively with high-dose steroids, and symptoms significantly improved. This case describes a rare phenomenon, pituitary apoplexy induced by GnRH agonist. We review the literature regarding this condition: the pathophysiological mechanism involved is not clearly established and several hypotheses have been proposed. Although uncommon, healthcare professionals and patients should be aware of this complication and recognize the signs, preventing a delay in diagnosis and treatment.
Pituitary apoplexy (PA) is a potentially life-threatening complication that can be caused by gonadotropin-releasing hormone agonist (GnRHa) administration for the treatment of advanced prostate cancer.
This complication is rare but should be taken into account when using GnRHa, particularly in the setting of a known pre-existing pituitary adenoma.
PA presents with classic clinical signs and symptoms that should be promptly recognized.
Patients should be instructed to seek medical care if suspicious symptoms occur.
Healthcare professionals should be aware of this complication, enabling its early recognition, adequate treatment and favorable outcome.
Postmenopausal hyperandrogenism is a relatively rare diagnosis resulting from excess androgen production from the adrenals or ovaries. The exclusion of malignant causes is a priority. Laboratory tests and imaging are utilised to help differentiate the source of excess androgens. We report two cases of postmenopausal hyperandrogenism in women aged 75 and 67 years. Both cases presented with clinical features suggestive of hyperandrogenism which had developed gradually over the previous 2 years. Laboratory investigations confirmed a significant elevation in their serum testosterone levels. In both cases, imaging did not reveal any abnormality of the adrenals or ovaries. To help differentiate an adrenal vs ovarian source a single-dose GnRH analogue was given with measurement of testosterone and gonadotrophin levels pre and post. The reduction in gonadotrophins achieved by the GnRH analogue resulted in suppression of testosterone levels which suggested an ovarian source. Both patients proceeded to bilateral oophorectomy. Histology revealed a benign hilus cell tumour in one case and a benign Leydig cell tumour in the other.
A key part of the work-up of postmenopausal hyperandrogenism is to differentiate between an adrenal or an ovarian source of excess androgens;
Imaging may not identify small ovarian tumours or hyperthecosis and may also identify incidental adrenal masses which are non-functioning;
Current guidelines suggest ovarian and adrenal venous sampling when imaging is inconclusive but this requires technical expertise and has a high failure rate;
GnRH analogue use can successfully confirm ovarian source and should be considered as a diagnostic tool in this setting.
Hypogonadotrophic hypogonadism is due to impaired or reduced gonadotrophin secretion from the pituitary gland. In the absence of any anatomical or functional lesions of the pituitary or hypothalamic gland, the hypogonadotrophic hypogonadism is referred to as idiopathic hypogonadotrophic hypogonadism (IHH). We present a case of a young lady born to consanguineous parents who was found to have IHH due to a rare gene mutation.
The genetic basis of a majority of cases of IHH remains unknown.
IHH can have different clinical endocrine manifestations.
Patients can present late to the healthcare service because of unawareness and stigmata associated with the clinical features.
Family members of affected individuals can be affected to varying degrees.
Kallmann syndrome is a genetically heterogeneous form of hypogonadotropic hypogonadism caused by gonadotropin-releasing hormone deficiency and characterized by anosmia or hyposmia due to hypoplasia of the olfactory bulbs; osteoporosis and metabolic syndrome can develop due to longstanding untreated hypogonadism. Kallmann syndrome affects 1 in 10 000 men and 1 in 50 000 women. Defects in 17 genes, including KAL1, have been implicated. Kallmann syndrome can be associated with X-linked ichthyosis, a skin disorder characterized by early onset dark, dry, irregular scales affecting the limb and trunk, caused by a defect of the steroid sulfatase gene (STS). Both KAL1 and STS are located in the Xp22.3 region; therefore, deletions in this region cause a contiguous gene syndrome. We report the case of a 32-year-old man with ichthyosis referred for evaluation of excessive height (2.07 m) and weight (BMI: 29.6 kg/m2), microgenitalia and absence of secondary sex characteristics. We diagnosed Kallmann syndrome with ichthyosis due to a deletion in Xp22.3, a rare phenomenon.
Kallmann syndrome is a genetically heterogeneous disease characterized by hypogonadotropic hypogonadism with anosmia or hyposmia associated with defects in the production or action of gonadotropin-releasing hormone (GnRH) and hypoplasia of the olfactory bulbs.
Several genes have been implicated in Kallmann syndrome, including KAL1, located in the Xp22.3 region, which is responsible for X-linked Kallmann syndrome. KAL1 encodes the protein anosmin-1. X-linked ichthyosis is caused by deficiency of the steroid sulfatase enzyme, encoded by STS, which is also located in the Xp22.3 region. Deletions involving this region can affect both genes and result in contiguous gene syndromes.
Phenotype can guide clinicians toward suspicion of a specific genetic mutation. KAL1 mutations are mostly related to microgenitalia, unilateral renal agenesis and synkinesia, although patients need not present all these abnormalities.
Longstanding untreated hypogonadism is associated with poor sexual health, osteoporosis and metabolic syndrome with the concomitant risk of developing type 2 diabetes mellitus and obesity.
Treatment aims to promote the development of secondary sex characteristics, build and sustain normal bone and muscle mass and restore fertility. Treatment can also help minimize some psychological consequences.
Treatments available for patients with congenital GnRH deficiency such as Kallmann syndrome include gonadal steroid hormones, human gonadotropins and GnRH. The choice of therapy depends on the goal or goals.
Primary amenorrhoea is defined as the failure to commence menstruation by the age of 15 years, in the presence of normal secondary sexual development. The potential causes of primary amenorrhoea extend from structural to chromosomal abnormalities. Polycystic ovarian syndrome (PCOS) is a common cause of secondary amenorrhoea but an uncommon cause of primary amenorrhoea. An early and prompt diagnosis of PCOS is important, as up to 30% of these women are predisposed to glucose intolerance and obesity, with the subgroup of women presenting with primary amenorrhoea and PCOS displaying a higher incidence of metabolic dysfunction. We describe a case of an 18-year-old female presenting with primary amenorrhoea of unknown aetiology. Although initial investigations did not demonstrate clinical or biochemical hyperandrogenism or any radiological evidence of polycystic ovaries, a raised luteinising hormone (LH) suggested a diagnosis of PCOS. If PCOS was the correct diagnosis, then one would expect intact hypothalamic GnRH and pituitary gonadotropin release. We used the novel hormone kisspeptin to confirm intact hypothalamic GnRH release and a GnRH stimulation test to confirm intact pituitary gonadotroph function. This case highlights that kisspeptin is a potential unique tool to test GnRH function in patients presenting with reproductive disorders.
Polycystic ovarian syndrome (PCOS) can present with primary amenorrhoea, and therefore, should be considered in the differential diagnosis.
PCOS is a heterogeneous condition that may present in lean women with few or absent signs of hyperandrogenism.
GnRH stimulation tests are useful in evaluating pituitary function; however, to date, we do not have a viable test of GnRH function. Kisspeptin has the potential to form a novel diagnostic tool for assessing hypothalamic GnRH function by monitoring gonadotropin response as a surrogate marker of GnRH release.
Confirmation of intact GnRH function helps consolidate a diagnosis in primary amenorrhoea and gives an indication of future fertility.
Pituitary apoplexy represents an uncommon endocrine emergency with potentially life-threatening consequences. Drug-induced pituitary apoplexy is a rare but important consideration when evaluating patients with this presentation. We describe an unusual case of a patient with a known pituitary macroadenoma presenting with acute-onset third nerve palsy and headache secondary to tumour enlargement and apoplexy. This followed gonadotropin-releasing hormone (GNRH) agonist therapy used to treat metastatic prostate carcinoma. Following acute management, the patient underwent transphenoidal debulking of his pituitary gland with resolution of his third nerve palsy. Subsequent retrospective data interpretation revealed that this had been a secretory gonadotropinoma and GNRH agonist therapy resulted in raised gonadotropins and testosterone. Hence, further management of his prostate carcinoma required GNRH antagonist therapy and external beam radiotherapy. This case demonstrates an uncommon complication of GNRH agonist therapy in the setting of a pituitary macroadenoma. It also highlights the importance of careful, serial data interpretation in patients with pituitary adenomas. Finally, this case presents a unique insight into the challenges of managing a hormonal-dependent prostate cancer in a patient with a secretory pituitary tumour.
While non-functioning gonadotropinomas represent the most common form of pituitary macroadenoma, functioning gonadotropinomas are exceedingly rare.
Acute tumour enlargement, with potential pituitary apoplexy, is a rare but important adverse effect arising from GNRH agonist therapy in the presence of both functioning and non-functioning pituitary gonadotropinomas.
GNRH antagonist therapy represents an alternative treatment option for patients with hormonal therapy-requiring prostate cancer, who also have diagnosed with a pituitary gonadotropinoma.