Diagnosis and Treatment > Signs and Symptoms

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Rob Gonsalves Division of Endocrinology, Phoenix Children’s Hospital, Phoenix, Arizona, USA

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Kirk Aleck Division of Genetics, Phoenix Children’s Hospital, Phoenix, Arizona, USA

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Dorothee Newbern Division of Endocrinology, Phoenix Children’s Hospital, Phoenix, Arizona, USA

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Gabriel Shaibi Division of Endocrinology, Phoenix Children’s Hospital, Phoenix, Arizona, USA

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Chirag Kapadia Division of Endocrinology, Phoenix Children’s Hospital, Phoenix, Arizona, USA

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Oliver Oatman Division of Endocrinology, Phoenix Children’s Hospital, Phoenix, Arizona, USA

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Summary

Single-minded homolog 1 (SIM1) is a transcription factor that plays a role in the development of both the hypothalamus and pituitary. SIM1 gene mutations are known to cause obesity in humans, and chromosomal deletions encompassing SIM1 and other genes necessary for pituitary development can cause a Prader–Willi-like syndrome with obesity and hypopituitarism. There have been no reported cases of hypopituitarism linked to a single SIM1 mutation. A 21-month-old male presented to endocrinology clinic with excessive weight gain and severe obesity. History was also notable for excessive drinking and urination. Endocrine workup revealed central hypothyroidism, partial diabetes insipidus, and central adrenal insufficiency. Genetic evaluation revealed a novel mutation in the SIM1 gene. No other genetic abnormalities to account for his obesity and hypopituitarism were identified. While we cannot definitively state this mutation is pathogenic, it is notable that SIM1 plays a role in the development of all three of the patient’s affected hormone axes. He is now 6 years old and remains on treatment for his pituitary hormone deficiencies and continues to exhibit excessive weight gain despite lifestyle interventions.

Learning points:

  • Mutations in SIM1 are a well-recognized cause of monogenic human obesity, and there have been case reports of Prader–Willi-like syndrome and hypopituitarism in patients with chromosomal deletions that contain the SIM1 gene.

  • SIM1 is expressed during the development of the hypothalamus, specifically in neuroendocrine lineages that give rise to the hormones oxytocin, arginine vasopressin, thyrotropin-releasing hormone, corticotropin-releasing hormone, and somatostatin.

  • Pituitary testing should be considered in patients with severe obesity and a known genetic abnormality affecting the SIM1 gene, particularly in the pediatric population.

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Taieb Ach Department of Endocrinology and Diabetology, Douai Hospital Center, Douai, France
Department of Endocrinology, University Hospital of Farhat Hached Sousse

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Perrine Wojewoda Department of Endocrinology and Diabetology, Douai Hospital Center, Douai, France

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Flora Toullet Department of Endocrinology and Diabetology, Douai Hospital Center, Douai, France

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Roxane Ducloux Department of Endocrinology and Diabetology, Douai Hospital Center, Douai, France

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Véronique Avérous Department of Endocrinology and Diabetology, Douai Hospital Center, Douai, France

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Summary

Multiple endocrine metastases are a rare but possible complication of lung adenocarcinoma (LAC). Pituitary metastasis is a rare condition with poor clinical expression. Diabetes insipidus (DI) is its most common presenting symptom. Here we report an original case of a pituitary stalk (PS) metastasis from LAC presenting as central DI followed by adrenal insufficiency (AI) from bilateral adrenal metastasis, without known evidence of the primary malignancy. A 45-year-old woman whose first clinical manifestations were polyuria and polydipsia was admitted. She was completely asymptomatic with no cough, no weight loss or anorexia. Chest radiography was normal. Brain MRI showed a thick pituitary stalk (PS). DI was confirmed by water restriction test and treated with vasopressin with great clinical results. Explorations for systemic and infectious disease were negative. Few months later, an acute AI led to discovering bilateral adrenal mass on abdominal CT. A suspicious 2.3 cm apical lung nodule was found later. Histopathological adrenal biopsy revealed an LAC. The patient received systemic chemotherapy with hormonal replacement for endocrinological failures by both vasopressin and hydrocortisone. We present this rare case of metastatic PS thickness arising from LAC associated with bilateral adrenal metastasis. Screening of patients with DI and stalk thickness for lung and breast cancer must be considered. Multiple endocrine failures as a diagnostic motive of LAC is a rare but possible circumstance.

Learning points:

  • Adrenal metastasis is a common location in lung adenocarcinoma; however, metastatic involvement of the pituitary stalk remains a rare occurrence, especially as a leading presentation to diagnose lung cancer.

  • The posterior pituitary and the infundibulum are the preferential sites for metastases, as they receive direct arterial blood supply from hypophyseal arteries.

  • Patients diagnosed with diabetes insipidus due to pituitary stalk thickness should be considered as a metastasis, after exclusion of the classical systemic and infectious diseases.

  • The diagnosis of an endocrinological metastatic primary lung adenocarcinoma for patients without respiratory symptoms is often delayed due to a lack of correlation between endocrinological symptoms and lung cancer.

  • The main originality of our case is the concomitant diagnosis of both endocrinological failures, as it was initiated with a diabetes insipidus and followed by an acute adrenal insufficiency.

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Aishah Ekhzaimy Department of Medicine and College of Medicine, King Saud University, Riyadh, Saudi Arabia

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Afshan Masood Obesity Research Center, and College of Medicine, King Saud University, Riyadh, Saudi Arabia

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Seham Alzahrani Department of Medicine and College of Medicine, King Saud University, Riyadh, Saudi Arabia

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Waleed Al-Ghamdi Department of Medicine and College of Medicine, King Saud University, Riyadh, Saudi Arabia

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Daad Alotaibi Department of Medicine and College of Medicine, King Saud University, Riyadh, Saudi Arabia

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Muhammad Mujammami Department of Medicine and College of Medicine, King Saud University, Riyadh, Saudi Arabia

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Summary

Central diabetes insipidus (CDI) and several endocrine disorders previously classified as idiopathic are now considered to be of an autoimmune etiology. Dermatomyositis (DM), a rare autoimmune condition characterized by inflammatory myopathy and skin rashes, is also known to affect the gastrointestinal, pulmonary, and rarely the cardiac systems and the joints. The association of CDI and DM is extremely rare. After an extensive literature search and to the best of our knowledge this is the first reported case in literature, we report the case of a 36-year-old male with a history of CDI, who presented to the hospital’s endocrine outpatient clinic for evaluation of a 3-week history of progressive facial rash accompanied by weakness and aching of the muscles.

Learning points:

  • Accurate biochemical diagnosis should always be followed by etiological investigation.

  • This clinical entity usually constitutes a therapeutic challenge, often requiring a multidisciplinary approach for optimal outcome.

  • Dermatomyositis is an important differential diagnosis in patients presenting with proximal muscle weakness.

  • Associated autoimmune conditions should be considered while evaluating patients with dermatomyositis.

  • Dermatomyositis can relapse at any stage, even following a very long period of remission.

  • Maintenance immunosuppressive therapy should be carefully considered in these patients.

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Ilan Rahmani Tzvi-Ran Department of Internal Medicine F, Soroka University Medical Center, Beer Sheva, Israel

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Judith Olchowski Department of Internal Medicine F, Soroka University Medical Center, Beer Sheva, Israel

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Merav Fraenkel Department of Internal Medicine F, Soroka University Medical Center, Beer Sheva, Israel

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Asher Bashiri Department of Internal Medicine F, Soroka University Medical Center, Beer Sheva, Israel

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Leonid Barski Department of Internal Medicine F, Soroka University Medical Center, Beer Sheva, Israel

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Summary

A previously healthy 24-year-old female underwent an emergent caesarean section without a major bleeding described. During the first post-operative days (POD) she complained of fatigue, headache and a failure to lactate with no specific and conclusive findings on head CT. On the following days, fever rose with a suspicion of an obstetric surgery-related infection, again with no evidence to support the diagnosis. On POD5 a new-onset hyponatremia was documented. The urine analysis suggested SIADH, and following a treatment failure, further investigation was performed and demonstrated both central hypothyroidism and adrenal insufficiency. The patient was immediately treated with hydrocortisone followed by levothyroxine with a rapid resolution of symptoms and hyponatremia. Further laboratory investigation demonstrated anterior hypopituitarism. The main differential diagnosis was Sheehan’s syndrome vs lymphocytic hypophysitis. Brain MRI was performed as soon as it was available and findings consistent with Sheehan’s syndrome confirmed the diagnosis. Lifelong hormonal replacement therapy was initiated. Further complaints on polyuria and polydipsia have led to a water deprivation testing and the diagnosis of partial central insipidus and appropriate treatment with DDAVP.

Learning points:

  • Sheehan’s syndrome can occur, though rarely, without an obvious major post-partum hemorrhage.

  • The syndrome may resemble lymphocytic hypophysitis clinically and imaging studies may be crucial in order to differentiate both conditions.

  • Hypopituitarism presentation may be variable and depends on the specific hormone deficit.

  • Euvolemic hyponatremia workup must include thyroid function test and 08:00 AM cortisol levels.

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Mara Ventura Department of Endocrinology, Diabetes and Metabolism

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Leonor Gomes Department of Endocrinology, Diabetes and Metabolism

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Joana Rosmaninho-Salgado Department of Medical Genetics, Pediatric Unit, Coimbra Hospital and Universitary Center, Coimbra, Portugal

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Luísa Barros Department of Endocrinology, Diabetes and Metabolism

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Isabel Paiva Department of Endocrinology, Diabetes and Metabolism

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Miguel Melo Department of Endocrinology, Diabetes and Metabolism

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Diana Oliveira Department of Endocrinology, Diabetes and Metabolism

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Francisco Carrilho Department of Endocrinology, Diabetes and Metabolism

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Summary

Intracranial germinomas are rare tumors affecting mostly patients at young age. Therefore, molecular data on its etiopathogenesis are scarce. We present a clinical case of a male patient of 25 years with an intracranial germinoma and a 16p11.2 microdeletion. His initial complaints were related to obesity, loss of facial hair and polydipsia. He also had a history of social-interaction difficulties during childhood. His blood tests were consistent with hypogonadotropic hypogonadism and secondary adrenal insufficiency, and he had been previously diagnosed with hypothyroidism. He also presented with polyuria and polydipsia and the water deprivation test confirmed the diagnosis of diabetes insipidus. His sellar magnetic resonance imaging (MRI) showed two lesions: one located in the pineal gland and other in the suprasellar region, both with characteristics suggestive of germinoma. Chromosomal microarray analysis was performed due to the association of obesity with social disability, and the result identified a 604 kb 16p11.2 microdeletion. The surgical biopsy confirmed the histological diagnosis of a germinoma. Pharmacological treatment with testosterone, hydrocortisone and desmopressin was started, and the patient underwent radiotherapy (40 Gy divided in 25 fractions). Three months after radiotherapy, a significant decrease in suprasellar and pineal lesions without improvement in pituitary hormonal deficiencies was observed. The patient is currently under follow-up. To the best of our knowledge, we describe the first germinoma in a patient with a 16p11.2 deletion syndrome, raising the question about the impact of this genetic alteration on tumorigenesis and highlighting the need of molecular analysis of germ cell tumors as only little is known about their genetic background.

Learning points:

  • Central nervous system germ cell tumors (CNSGTs) are rare intracranial tumors that affect mainly young male patients. They are typically located in the pineal and suprasellar regions and patients frequently present with symptoms of hypopituitarism.

  • The molecular pathology of CNSGTs is unknown, but it has been associated with gain of function of the KIT gene, isochromosome 12p amplification and a low DNA methylation.

  • Germinoma is a radiosensitive tumor whose diagnosis depends on imaging, tumor marker detection, surgical biopsy and cerebrospinal fluid cytology.

  • 16p11.2 microdeletion syndrome is phenotypically characterized by developmental delay, intellectual disability and autism spectrum disorders.

  • Seminoma, cholesteatoma, desmoid tumor, leiomyoma and Wilms tumor have been described in a few patients with 16p11.2 deletion.

  • Bifocal germinoma was identified in this patient with a 16p11.2 microdeletion syndrome, which represents a putative new association not previously reported in the literature.

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Laura Hamilton Adams Department of Endocrinology, Diabetes, and Metabolism, University of Kentucky, Lexington, Kentucky, USA

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Derick Adams Department of Endocrinology, Diabetes, and Metabolism, University of Kentucky, Lexington, Kentucky, USA

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Summary

Co-secreting TSH and growth hormone pituitary adenomas are rare. We present a case of a 55-year-old woman who presented with symptoms of neck fullness. Ultrasound revealed multiple thyroid nodules and examination revealed several clinical features of acromegaly. She was found to have a co-secreting TSH and growth hormone pituitary macroadenoma. She underwent surgical resection followed by gamma knife radiation, which resulted in complete remission of her TSH and GH-secreting adenoma.

Learning points:

  • TSH-secreting pituitary adenomas are rare and about one-third co-secrete other hormones.

  • Thyroid nodules are common in acromegaly and can be the presenting sign of a growth hormone-secreting pituitary adenoma.

  • In the workup of acromegaly, assessment of other pituitary hormones is essential, even in the absence of symptoms of other pituitary hormone dysfunction.

  • Complete remission of co-secreting GH and TSH pituitary macroadenomas is possible with surgery and radiation alone.

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Natassia Rodrigo Department of Endocrinology and Diabetes, Royal North Shore Hospital, Sydney, and University of Sydney, Sydney, Australia

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Samantha Hocking Department of Endocrinology and Diabetes, Royal North Shore Hospital, Sydney, and University of Sydney, Sydney, Australia

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Summary

This case illustrates the exceedingly rare phenomenon of transient diabetes insipidus, in association with pre-eclampsia, occurring in the post-partum period following an in vitro fertilisation pregnancy, in an otherwise well 48-year-old lady. Diabetes insipidus can manifest during pregnancy, induced by increased vasopressinase activity secreted by placental trophoblasts and usually manifests in the third trimester. This presentation elucidates not only the intricate balance between the physiology of pregnancy and hormonal homeostasis, but also the importance of post-partum care as the physiological changes of pregnancy still hold pathological potential in the weeks immediately following delivery.

Learning points:

  • Diabetes insipidus (DI) is a rare complication of pregnancy occurring in 1 in 30 000 pregnancies.

  • It is associated with excessive vasopressinase activity, secreted by placental trophoblasts, which increases the rate of degradation of anti-diuretic hormone.

  • It is responsive to synthetic desmopressin 1-deanimo-8-d-arginine vasopressin as this form is not degraded by placental vasopressinase.

  • Vasopressinase is proportional to placental weight, which is increased in pregnancies conceived with assisted reproductive techniques including in vitro fertilisation.

  • Vasopressinase-induced DI is associated with pre-eclampsia.

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Snezana Burmazovic Department of Intensive Care Medicine, Lucerne Cantonal Hospital, Lucerne, Switzerland

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Christoph Henzen Department of Internal Medicine and Endocrinology, Lucerne Cantonal Hospital, Lucerne, Switzerland

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Lukas Brander Department of Intensive Care Medicine, Lucerne Cantonal Hospital, Lucerne, Switzerland

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Luca Cioccari Department of Intensive Care Medicine, Lucerne Cantonal Hospital, Lucerne, Switzerland
Australian and New Zealand Intensive Care Research Centre, School of Public Health and Preventive Medicine, Monash University, Prahran, Australia

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Summary

The combination of hyperosmolar hyperglycaemic state and central diabetes insipidus is unusual and poses unique diagnostic and therapeutic challenges for clinicians. In a patient with diabetes mellitus presenting with polyuria and polydipsia, poor glycaemic control is usually the first aetiology that is considered, and achieving glycaemic control remains the first course of action. However, severe hypernatraemia, hyperglycaemia and discordance between urine-specific gravity and urine osmolality suggest concurrent symptomatic diabetes insipidus. We report a rare case of concurrent manifestation of hyperosmolar hyperglycaemic state and central diabetes insipidus in a patient with a history of craniopharyngioma.

Learning points:

  • In patients with diabetes mellitus presenting with polyuria and polydipsia, poor glycaemic control is usually the first aetiology to be considered.

  • However, a history of craniopharyngioma, severe hypernatraemia, hyperglycaemia and discordance between urine-specific gravity and osmolality provide evidence of concurrent diabetes insipidus.

  • Therefore, if a patient with diabetes mellitus presents with severe hypernatraemia, hyperglycaemia, a low or low normal urinary-specific gravity and worsening polyuria despite correction of hyperglycaemia, concurrent diabetes insipidus should be sought.

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Florence Gunawan Geelong University Hospital, Barwon Health, Geelong, Victoria, Australia

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Elizabeth George
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Adam Roberts
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Summary

Immune checkpoint inhibitors are the mainstay of treatment for advanced melanoma, and their use is being increasingly implicated in the development of autoimmune endocrinopathies. We present a case of a 52-year-old man with metastatic melanoma on combination nivolumab and ipilumimab therapy who developed concurrent hypophysitis, type 1 diabetes mellitus (T1DM) and diabetes insipidus. He presented prior to third cycle of combination treatment with a headache, myalgias and fatigue. Biochemistry and MRI pituitary confirmed anterior pituitary dysfunction with a TSH: 0.02 mU/L (0.5–5.5 mU/L), fT4: 5.2 pmol/L (11–22 pmol/L), fT3: 4.0 pmol/L (3.2–6.4 pmol/L), cortisol (12:00 h): <9 nmol/L (74–286 nmol/L), FSH: 0.7 IU/L (1.5–9.7 IU/L), LH: <0.1 IU/L (1.8–9.2 IU/L), PRL: 1 mIU/L (90–400 mIU/L), SHBG: 34 nmol/L (19–764 nmol/L) and total testosterone: <0.4 nmol/L (9.9–27.8 nmol/L). High-dose dexamethasone (8 mg) was administered followed by hydrocortisone, thyroxine and topical testosterone replacement. Two weeks post administration of the third cycle, he became unwell with lethargy, weight loss and nocturia. Central diabetes insipidus was diagnosed on the basis of symptoms and sodium of 149 mmol/L (135–145 mmol/L). Desmopressin nasal spray was instituted with symptom resolution and normalization of serum sodium. Three weeks later, he presented again polyuric and polydipsic. His capillary glucose was 20.8 mmol/L (ketones of 2.4 mmol), low C-peptide 0.05 nmol/L (0.4–1.5 nmol/L) and HbA1c of 7.7%. T1DM was suspected, and he was commenced on an insulin infusion with rapid symptom resolution. Insulin antibodies glutamic acid decarboxylase (GAD), insulin antibody-2 (IA-2) and zinc transporter-8 (ZnT8) were negative. A follow-up MRI pituitary revealed findings consistent with recovering autoimmune hypophysitis. Immunotherapy was discontinued based on the extent of these autoimmune endocrinopathies.

Learning points:

  • The most effective regime for treatment of metastatic melanoma is combination immunotherapy with nivolumab and ipilumimab, and this therapy is associated with a high incidence of autoimmune endocrinopathies.

  • Given the high prevalence of immune-related adverse events, the threshold for functional testing should be low.

  • Traditional antibody testing may not be reliable to identify early-onset endocrinopathy.

  • Routine screening pathways have yet to be adequately validated through clinical trials.

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Alicia R Jones Department of Endocrinology and Diabetes, Western Health, St Albans, Victoria, Australia

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Alan McNeil Dorevitch Pathology, Heidelberg, Victoria, Australia

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Christopher Yates Department of Endocrinology and Diabetes, Western Health, St Albans, Victoria, Australia
Department of Medicine, The University of Melbourne (Royal Melbourne Hospital), Parkville, Victoria, Australia

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Bala Krishnamurthy Department of Endocrinology and Diabetes, Western Health, St Albans, Victoria, Australia
Department of Medicine, The University of Melbourne (St. Vincent’s Hospital), Fitzroy, Victoria, Australia

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Peter S Hamblin Department of Endocrinology and Diabetes, Western Health, St Albans, Victoria, Australia
Department of Medicine, The University of Melbourne (Western Campus), St Albans, Victoria, Australia

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Summary

A variety of neoplastic, inflammatory and congenital conditions can cause pituitary stalk thickening. Differentiating between these causes is important as targeted treatment may be offered. Diagnostic work-up consists of a thorough history, examination, biochemical analysis and imaging. We present the case of a 33-year-old male who presented with diabetes insipidus and had pituitary stalk thickening on magnetic resonance imaging. Further investigations revealed an elevated CSF βhCG, which raised the possibility of an intracranial germ cell tumor. However, when repeated on four different assays, the βhCG levels were discordant. On serial imaging, the pituitary stalk thickening reduced slightly, which would be unexpected for a germ cell tumor. This case raises the difficulties interpreting CSF βhCG, as not all immunoassays for βhCG have been validated for use in CSF. The Roche Diagnostics Elecsys and Siemens Centaur assays have been validated for CSF βhCG, and so we advocate using one of these methods. If unavailable or serum/CSF results are ambiguous, serial MRI is appropriate, with pituitary stalk biopsy considered if the stalk measures >6.5 mm or other imaging abnormalities are present.

Learning points:

  • Most adult patients with central diabetes insipidus have imaging abnormalities on a pituitary MRI. The most common abnormalities are loss of the posterior pituitary bright spot and pituitary stalk thickening, both of which are non-specific.

  • Causes of pituitary stalk thickening include neoplastic, inflammatory, infective and congenital lesions.

  • Investigation of pituitary stalk thickening should encompass the many possible causes and include biochemical analyses as well as imaging of the chest, abdomen and pelvis. Further investigations should be guided by the clinical context, but may include testicular ultrasound, CSF analysis and pituitary stalk biopsy.

  • Germ cell tumors involving the pituitary stalk may be suspected on clinical grounds, but in the absence of a tissue diagnosis (biopsy) confirmation may be difficult and relies on biochemical assessment of blood and possibly CSF as well as serial MRI imaging.

  • CSF βhCG levels should be analyzed on an instrument validated for use in CSF or on multiple instruments, and the pitfalls of testing this marker (false negative in some germ cell tumors, false positives in other conditions, lack of internationally agreed reference ranges for diagnosing germ cell tumors) should be considered when interpreting the results.

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