Diagnosis and Treatment > Investigation > Water deprivation

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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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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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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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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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Raluca Maria Furnica Departments of Endocrinology, Pathology, and Neuroradiology, Université catholique de Louvain, Cliniques Universitaires Saint-Luc, Brussels, Belgium

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Julie Lelotte Departments of Pathology, and Neuroradiology, Université catholique de Louvain, Cliniques Universitaires Saint-Luc, Brussels, Belgium

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Thierry Duprez Departments of Neuroradiology, Université catholique de Louvain, Cliniques Universitaires Saint-Luc, Brussels, Belgium

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Dominique Maiter Departments of Endocrinology, Pathology, and Neuroradiology, Université catholique de Louvain, Cliniques Universitaires Saint-Luc, Brussels, Belgium

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Orsalia Alexopoulou Departments of Endocrinology, Pathology, and Neuroradiology, Université catholique de Louvain, Cliniques Universitaires Saint-Luc, Brussels, Belgium

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Summary

A 26-year-old woman presented with severe postpartum headaches. Magnetic resonance imaging (MRI) revealed a symmetric, heterogeneous enlargement of the pituitary gland. Three months later, she developed central diabetes insipidus. A diagnosis of postpartum hypophysitis was suspected and corticosteroids were prescribed. Six months later, the pituitary mass showed further enlargement and characteristics of a necrotic abscess with a peripheral shell and infiltration of the hypothalamus. Transsphenoidal surgery was performed, disclosing a pus-filled cavity which was drained. No bacterial growth was observed, except a single positive blood culture for Staphylococcus aureus, considered at that time as a potential contaminant. A short antibiotic course was, however, administered together with hormonal substitution for panhypopituitarism. Four months after her discharge, severe headaches recurred. Pituitary MRI was suggestive of a persistent inflammatory mass of the sellar region. She underwent a new transsphenoidal resection of a residual abscess. At that time, the sellar aspiration fluid was positive for Staphylococcus aureus and she was treated with antibiotics for 6 weeks, after which she had complete resolution of her infection. The possibility of a pituitary abscess, although rare, should be kept in mind during evaluation for a necrotic inflammatory pituitary mass with severe headaches and hormonal deficiencies.

Learning points:

  • The possibility of a pituitary abscess, although rare, should be kept in mind during evaluation for a necrotic inflammatory pituitary mass with severe headaches and hormonal deficiencies.

  • In a significant proportion of cases no pathogenic organism can be isolated.

  • A close follow-up is necessary given the risk of recurrence and the high rate of postoperative pituitary deficiencies.

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Rayna Patel Department of Stroke Medicine, Addenbrooke’s Hospital, Cambridge, UK

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Waheed Mustafa Department of Orthopaedic Surgery, Basildon University Hospital, Nethermayne, Basildon, Essex, UK

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Michael T Sheaff Department of Pathology, St Bartholemew’s Hospital, London, UK

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Sami Khan Department of Radiology, Basildon University Hospital, Nethermayne, Basildon, Essex, UK

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Summary

IgG4-related disease (IgG4-RD) is a rare but increasingly recognised condition, emerging as a clinical entity following the observation of the associations of autoimmune pancreatitis. IgG4-RD is characterised by extensive infiltration of IgG4-positive plasma cells into multiple organs and raised serum IgG4 levels. Clinical manifestations of IgG4 disease classically include autoimmune pancreatitis, lacrimal or salivary gland infiltration (formerly known as Mikulicz disease) and retroperitoneal fibrosis. More rarely, IgG4 disease can cause pituitary hypophysitis. Although most frequently described in middle-aged males, the epidemiology and pathogenesis of the disease remain largely undefined. Nevertheless, an understanding of the wide variety of clinical manifestations of this multi-system condition is undeniably important given the often excellent outcomes following treatment. We describe an unusual presentation of IgG4 disease with isolated diabetes insipidus secondary to pituitary hypophysitis. The patient in question subsequently developed chest pain secondary to mediastinal lymphadenopathy and tubulo-interstitial nephritis leading to renal dysfunction. He was successfully treated with oral steroids and had regular follow-up, and remains well at follow-up 2 years later.

Learning points

  • IgG4 disease, although rare, is increasing in prevalence largely due to increased recognition of its clinical manifestations, including autoimmune pancreatitis, lacrimal or salivary gland infiltration, retroperitoneal fibrosis and, more rarely, lymphocytic hypophysitis presenting as diabetes insipidus.

  • IgG4 disease is highly treatable, and symptoms may show complete resolution with administration of steroids, highlighting the importance of correct and timely diagnosis.

  • Causes of lymphocytic hypophysitis are varied and not distinguishable radiologically. Given the difficulty in biopsying the pituitary, careful attention must be paid to the systemic clinical presentation to provide clues as to the underlying disorder.

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Huanyu Ding Department of Endocrinology and Metabolism, the First Affiliated Hospital of Sun Yat-sen University, Guangzhou, 510080, People's Republic of China

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Yang Li Department of Pathology, the First Affiliated Hospital of Sun Yat-sen University, Guangzhou, 510080, People's Republic of China

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Caishun Ruan Department of Endocrinology and Metabolism, Longyan People Hospital, Longyan, 364000, People's Republic of China

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Yuan Gao Department of General Practice, Community Health Center of Qianjin Street, Tianhe District, Guangzhou, 510660, People's Republic of China

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Hehua Wang Department of Hematology, the First Affiliated Hospital of Sun Yat-sen University, Guangzhou, 510080, People's Republic of China

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Xiangsong Zhang Department Nuclear Medicine, the First Affiliated Hospital of Sun Yat-sen University, Guangzhou, 510080, People's Republic of China

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Zhihong Liao Department of Endocrinology and Metabolism, the First Affiliated Hospital of Sun Yat-sen University, Guangzhou, 510080, People's Republic of China

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Summary

Erdheim-Chester disease (ECD), one type of systemic non-Langerhans cell histiocytosis, has been rarely seen and is characterized by the accumulation of foamy CD68+CD1a- histiocytes. We reported a case of ECD and reviewed the clinical features of 13 cases of ECD reported so far in China. A 53-year-old male was diagnosed with central diabetes insipidus in March 2014, followed by fever, splenomegaly and anemia in July 2014. His initial pituitary magnetic resonance imaging (MRI) revealed the absence of high signal at T1-weighted image in posterior pituitary without any lesion. A further positron emission tomography/computer tomography (PET/CT) images showed elevated metabolic activity of 18F-2-fluro-D-deoxy-glucose (FDG) and low 13N-NH3 uptake in the posterior pituitary, and multi-organ involvement. Biopsy at right femur lesion revealed that granulomatous infiltration of foamy histiocytes and Touton giant cells surrounded by fibrosis tissues. Immunohistochemistry stain was positive for CD68, negative for CD207/Langerin and S-100. The diagnosis of ECD was confirmed and the treatment with pegylated interferon was effective. ECD was a possible immune-related disorder concluding from the IgG4 immunohistochemistry results. We summarized the pathological manifestations for ECD and its differential diagnosis from Langerhans cell histiocytosis (LCH) and Rosai-Dorfman disease (RDD). ECD should be considered by both pathologists and clinicians in the differential diagnosis when central diabetes insipidus is accompanied with multi-organ involvement, especially skeletal system involvement, or recurrent fever.

Learning points

  • ECD should be considered when central diabetes insipidus is accompanied with multisystem involvement, especially symmetric/asymmetric bone lesions, or recurrent fever.

  • PET/CT scanning was helpful for locating pituitary lesion, discovering multiple system involvement and indicating the biopsy sites.

  • Conducting proper immunohistochemistry stains was important for diagnosing ECD. ECD might be correlated with immune disorder.

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Ramesh Srinivasan Department of Paediatric Endocrinology, Royal Victoria Infirmary, Newcastle-upon-Tyne Hospitals NHS Trust, Newcastle-upon-Tyne NE1 4LP, UK

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Stephen Ball Department of Endocrinology, Royal Victoria Infirmary, Newcastle-upon-Tyne NE1 4LP, UK
The Medical School, Newcastle University, Newcastle NE24HH, UK

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Martin Ward-Platt Ward 35, Royal Victoria Infirmary, Newcastle-upon-Tyne NE1 4LP, UK

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David Bourn The Institute of Genetic Medicine, Newcastle University, International Centre for Life, Central Parkway, Newcastle-upon-Tyne NE1 3BZ, UK

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Ciaron McAnulty The Institute of Genetic Medicine, Newcastle University, International Centre for Life, Central Parkway, Newcastle-upon-Tyne NE1 3BZ, UK

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Tim Cheetham Department of Paediatric Endocrinology, Royal Victoria Infirmary, Newcastle-upon-Tyne Hospitals NHS Trust, Newcastle-upon-Tyne NE1 4LP, UK
The Institute of Genetic Medicine, Newcastle University, International Centre for Life, Central Parkway, Newcastle-upon-Tyne NE1 3BZ, UK

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Summary

Aim: Differentiating familial cranial diabetes insipidus (CDI) from primary polydipsia can be difficult. We report the diagnostic utility of genetic testing as a means of confirming or excluding this diagnosis.

Patient and methods: The index case presented at 3 months with polydipsia. He was diagnosed with familial CDI based on a positive family history combined with what was considered to be suspicious symptomatology and biochemistry. He was treated with desmopressin (DDAVP) but re-presented at 5 months of age with hyponatraemia and the DDAVP was stopped. Gene sequencing of the vasopressin gene in father and his offspring was undertaken to establish the underlying molecular defect.

Results: Both father and daughter were found to have the pathogenic mutation c.242T>C (p.Leu81Pro) in exon 2 of the AVP gene consistent with a diagnosis of familial diabetes insipidus. The index case did not have the pathogenic mutation and the family could be reassured that he would not require intervention with DDAVP.

Conclusions: Gene sequencing of AVP gene can have a valuable role in predicting whether or not a child is at risk of developing CDI in future. This can help to prevent family uncertainty and unnecessary treatment with its associated risks.

Learning points

  • Differentiating patients with familial cranial diabetes insipidus from those with primary polydipsia is not always straightforward.

  • Molecular genetic analysis of the vasopressin gene is a valuable way of confirming or refuting a diagnosis of familial CDI in difficult cases and is a valuable way of identifying individuals who will develop CDI in later childhood. This information can be of great value to families.

Open access