Hypopituitarism with secondary adrenocortical insufficiency and arginine vasopressin deficiency due to hypophysitis after COVID-19 vaccination: a case report.

BACKGROUND: Although vaccination against coronavirus disease (COVID-19) has several side effects, hypopituitarism due to hypophysitis has rarely been reported. CASE PRESENTATION: An 83-year-old healthy woman, who had received her fourth COVID-19 vaccine dose 2 days before admission, presented to the emergency department with difficulty moving. On examination, impaired consciousness (Glasgow Coma Scale: 14) and fever were observed. Computed tomography and magnetic resonance imaging of the head revealed swelling from the sella turcica to the suprasellar region. Her morning serum cortisol level was low (4.4 µg/dL) and adrenocorticotropic hormone level was normal (21.6 pg/mL). Central hypothyroidism was also suspected (thyroid stimulating hormone, 0.46 µIU/mL; free triiodothyronine, 1.86 pg/mL; free thyroxine, 0.48 ng/dL). Secondary adrenocortical insufficiency, growth hormone deficiency, delayed gonadotropin response, and elevated prolactin levels were also observed. After administration of prednisolone and levothyroxine, her consciousness recovered. On the 7th day of admission, the patient developed polyuria, and arginine vasopressin deficiency was diagnosed using a hypertonic saline test. On the 15th day, the posterior pituitary gland showed a loss of high signal intensity and the polyuria resolved spontaneously. On the 134th day, the corticotropin-releasing hormone loading test showed a normal response; however, the thyrotropin-releasing hormone stimulation test showed a low response. The patient's disease course was stable with continued thyroid and adrenal corticosteroid supplementation. CONCLUSIONS: Herein, we report a rare case of anterior hypopituitarism and arginine vasopressin deficiency secondary to hypophysitis following COVID-19 vaccination.

Lymphocytic hypophysitis - various course of the disease and individualized therapeutic approach. An algorithm of the follow-up.

INTRODUCTION: Lymphocytic hypophysitis (LH) is a rare inflammatory disorder of the pituitary or/and hypothalamus with variable disease course: from spontaneous remission to pituitary atrophy. The diagnosis, treatment and follow-up remain challenging. The aim of the study is to present long-term data and an individualized therapeutic approach and propose an algorithm for the follow-up of patients with probable LH. MATERIAL AND METHODS: A retrospective analysis of 18 consecutive adult patients (13 W/5 M, mean age 45.2 years) with LH diagnosed and treated in a tertiary referral center. RESULTS: The first manifestations were headaches (50.0%), polyuria/polydipsia (33.3%) and symptoms of hypopituitarism (16.7%). Somatotropic, adrenal, gonadal and thyroid axis insufficiencies were found in 44.4%, 33.3%, 33.3%, and 27.8% of patients, respectively. Arginine vasopressin deficiency was diagnosed in 8 patients (44.4%). Some of the dysfunctions were transient. Magnetic resonance imaging (MRI) revealed thickened pituitary stalk in all but 2 cases. In 2 patients an anterior pituitary lesion, most likely inflammatory was described. Four patients were given steroids (severe headaches) with clinical recovery and stable/improved MRI. One woman was operated on due to the progressive mass-related symptoms - histopathological examination confirmed LH. In the remaining 13/18 patients watchful waiting approach allowed to obtain hormonal and radiological stabilization/improvement. CONCLUSIONS: LH is a disease with a complex clinical picture and challenging diagnosis. Treatment requires an individual approach: vigilant observation is the cornerstone of therapy, with steroid/surgical treatment reserved for cases with mass-related symptoms. Further multicenter research might help in better understanding of the LH and creating standards of care in this rare disease.

A Case of Hypernatremia in a Newly Diagnosed Patient With Acute Myeloid Leukemia: Lessons for Nephrologists.

Arginine vasopressin deficiency (AVP-D), formerly known as central diabetes insipidus, is a disease characterized by polyuria, polydipsia, and hypernatremia. The concomitant diagnosis of acute myeloid leukemia (AML) is an underappreciated event that requires prompt recognition and treatment by practicing nephrologists and hematologists. This report highlights this importance by describing the case of a 39-year-old patient newly diagnosed with AML who developed severe hypernatremia. The role of diagnostic testing through desmopressin (DDAVP) challenge and copeptin testing to confirm the diagnosis of AVP-D in this context and the use of DDVAP for treatment are discussed. Practicing nephrologists and primary care providers taking care of patients with similar symptoms will benefit from understanding the pathophysiology of AVP-D, its relationship with AML, and the prognosis in this patient cohort.

Effect of steroid therapy in a 16-year-old girl observed for lymphocytic hypophysitis.

Not required for Clinical Vignette.

Coexistence of type 2 diabetes mellitus, arginine vasopressin deficiency, and Marfan syndrome: A case report.

Diabetes mellitus (DM) and arginine vasopressin deficiency (AVP-D) are characterized by polyuria. Marfan syndrome is an autosomal dominant disorder caused by pathogenetic variants in FBN1. Here, we report a patient with type 2 diabetes mellitus, AVP-D, and Marfan syndrome. Although the coexistence of type 2 diabetes mellitus and AVP-D is rare, for those patients with type 2 diabetes mellitus, the existence of AVP-D should be considered when polyuria is not in accordance with the blood glucose levels, especially for those with a low urine specific gravity. Specific symptoms or signs help to identify Marfan syndrome early, and genetic testing of the FBN1 pathogenetic variant helps to make a definitive diagnosis.

Position statement on the diagnosis and management of congenital pituitary deficiency in adults: The French National Diagnosis and Treatment Protocol (NDTP).

Pituitary deficiency, or hypopituitarism, is a rare chronic disease. It is defined by insufficient synthesis of one or more pituitary hormones (growth hormone, TSH, ACTH, LH-FSH, prolactin), whether or not associated with arginine vasopressin deficiency (formerly known as diabetes insipidus). In adult patients, it is usually acquired (notably during childhood), but can also be congenital, due to abnormal pituitary development. The present study focuses on congenital pituitary deficiency in adults, from diagnosis to follow-up, including special situations such as pregnancy or the elderly. The clinical presentation is highly variable, ranging from isolated deficit to multiple deficits, which may be part of a syndromic form or not. Diagnosis is based on a combination of clinical, biological (assessment of all hormonal axes), radiological (brain and hypothalamic-pituitary MRI) and genetic factors. Treatment consists in hormonal replacement therapy, adapted according to the period of life and the deficits, which may be progressive. Comorbidities, risk of complications and acute decompensation, and the impact on fertility and quality of life all require adaptative multidisciplinary care and long-term monitoring.

Diabetes insipidus: Vasopressin deficiency….

Diabetes insipidus is a disorder characterized by hypo-osmotic polyuria secondary to abnormal synthesis, regulation, or renal action of antidiuretic hormone. Recently, an expert group, with the support of patient associations, proposed that diabetes insipidus be renamed to avoid confusion with diabetes mellitus. The most common form of diabetes insipidus is secondary to a dysfunction of the neurohypophysis (central diabetes insipidus) and would be therefore named â€Ìƒvasopressin deficiency’. The rarer form, which is linked to renal vasopressin resistance (nephrogenic diabetes insipidus), would then be named â€Ìƒvasopressin resistance’. The etiology of diabetes insipidus is sometimes clear, in the case of a neurohypophyseal cause (tumoral or infiltrative damage) or a renal origin, but in some cases diabetes insipidus can be difficult to distinguish from primary polydipsia, which is characterized by consumption of excessive quantities of water without any abnormality in regulation or action of antidiuretic hormone. Apart from patients’ medical history, physical examination, and imaging of the hypothalamic-pituitary region, functional tests such as water deprivation or stimulation of copeptin by hyperosmolarity (induced by infusion of hypertonic saline) can be proposed in order to distinguish between these different etiologies. The treatment of diabetes insipidus depends on the underlying etiology, and in the case of a central etiology, is based on the administration of desmopressin which improves patient symptoms but does not always result in an optimal quality of life. The cause of this altered quality of life may be oxytocin deficiency, oxytocin being also secreted from the neurohypophysis, though this has not been fully established. The possibility of a new test using stimulation of oxytocin to identify alterations in oxytocin synthesis is of interest and would allow confirmation of a deficiency in those patients presenting with diabetes insipidus linked to neurohypophyseal dysfunction.

Transient Central Diabetes Insipidus (Arginine Vasopressin Deficiency) Following SARS-CoV-2 Vaccination: A Case Report and Literature Review.

INTRODUCTION: Since December 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has affected millions of people, causing the COVID-19 global pandemic. The use of novel technologies led to the development of different types of SARS-CoV-2 vaccines that have reduced severe disease courses and related deaths. Besides the positive impact of vaccination on the pandemic, local and systemic side effects have been reported; they are usually mild to moderate, although also serious adverse events have been described. CASE PRESENTATION: A 21-year-old female was referred to our hospital for the recent onset of severe polyuria and polydipsia, with the need for about 8 liters of daily water intake. The symptoms developed seven days after the administration of the second dose of the mRNA-based (Pfizer-BioNTech® BNT162b2) SARS-CoV-2 vaccine. In the suspicion of central diabetes insipidus (DI) development, she started treatment with desmopressin (Minirin® tablets) 60 mg/day with an improvement of symptoms and thirst. A thickening of the pituitary stalk was observed at the pituitary MRI with loss of the posterior pituitary bright spot on T1 weighted images. To confirm the diagnosis of central DI, both the water deprivation test and arginine stimulated copeptin test were performed; whilst the former gave no clear-cut indication of DI, the latter showed a reduced copeptin peak after arginine infusion consistent with the diagnosis of partial central DI. Furthermore, the development of symptoms right after the second dose of the vaccine strengthened the hypothesis that DI was related to the vaccination itself. After our evaluation, there was a progressive reduction of desmopressin dose to a complete discontinuation with the maintenance of a normal hydroelectrolytic balance. Clinical and biochemical follow-up was performed by repeating a pituitary MRI and a second arginine-stimulated copeptin test 15 months after the diagnosis. This time, copeptin levels reached a significantly higher peak after arginine stimulation that completely excluded central DI and at pituitary MRI, the thickening of the pituitary stalk previously described was no longer visible. CONCLUSION: Neurohypophysitis can have an abrupt onset independently of the etiology. Central DI is a rather exceptional event after SARS-CoV-2 vaccination but should be recalled in case of sudden polyuria and polydipsia. DI is indeed reported even after SARS-CoV-2 infection, thus, this report should not discourage the use of mRNA-based vaccines. Furthermore, our case demonstrates that full recovery of posterior pituitary function is possible after immunization with anti-Covid-19 BNT162b2 vaccine. Further studies are needed to clarify the possible mechanism relating to SARS-CoV-2 vaccination and this rare adverse event.

Clinical Factors Affecting Daily Dosage of Desmopressin Orally Disintegrating Tablets in Arginine Vasopressin Deficiency.

CONTEXT: Desmopressin orally disintegrating tablets (ODTs) are widely used to treat arginine vasopressin deficiency (AVP-D). However, limited information is available on the dosage regimen; the dosage for each patient is selected based on their response to the initiation dose. OBJECTIVE: To investigate the relationships between clinical characteristics and the daily dose of ODTs and to identify factors that affect ODT dosages. METHODS: This retrospective study included 209 adult patients with AVP-D. Patients were administered ODTs sublingually and instructed to restrict eating and drinking for 30 minutes after taking ODTs using a patient leaflet. ODT dose titration was conducted during hospitalization with close monitoring of urine output, body weight, and serum sodium levels. Multivariable linear regression models were applied to identify clinical factors associated with the daily dose of ODTs at discharge. We also evaluated the dosage at 1 year in 134 patients who were followed up in our hospital. RESULTS: The median daily dose of ODTs at discharge was 90 µg (IQR 60-120 µg). Multivariable linear regression models identified sex, age, and estimated creatinine clearance (eCCr) as significant factors associated with the daily dose of ODTs, with eCCr having the strongest effect. After excluding patients recovering from AVP-D, 71% of those followed up at our hospital took the same daily dose at 1 year after discharge. CONCLUSION: To achieve the safe and stable treatment of AVP-D, the daily dose of ODT needs to be selected based on a patient's sex, age, and eCCr under appropriate sublingual administration by patient education.

Resumen ejecutivo del documento de consenso de expertos de la Sociedad Española de Neurocirugía y de la Sociedad Española de Endocrinología y Nutrición sobre: recomendaciones clínicas en el manejo perioperatorio de los tumores hipofisarios / Executive summary of the expert consensus document from the Spanish Society of Neurosurgery and the Spanish Society of Endocrinology and Nutrition: Clinical recommendations on the perioperative management of pituitary tumors

Los tumores hipofisarios (TH) suponen el 15% de los tumores intracraneales, y afectan del 10,7 al 14,4% de la población, si bien la incidencia de los TH clínicamente relevantes es de 5,1 casos/100.000 habitantes. El tratamiento quirúrgico está indicado en los TH que cursan con hipersecreción hormonal (a excepción de los TH productores de prolactina), así como en aquellos con clínica compresiva local o neurológica global. Los pacientes con TH requieren una atención multidisciplinar, idealmente en un centro de excelencia y basada en un protocolo asistencial bien definido. Con el objetivo de facilitar y estandarizar la práctica clínica ante este tipo de tumores, el presente documento recoge el posicionamiento del ÿrea de Conocimiento de Neuroendocrinología de la Sociedad Española de Endocrinología y Nutrición (SEEN) y la Sociedad Española de Neurocirugía (SENEC) sobre el manejo y el seguimiento prequirúrgico, quirúrgico y posquirúrgico del paciente con un TH (AU)

Pituitary tumors (PT) account for 15% of intracranial tumors affect 10.7 to 14.4% of the population although the incidence of clinically relevant PT is 5.1 cases/100,000 inhabitants. Surgical treatment is indicated in PTs with hormone hypersecretion (except for prolactin-producing PTs) and those with local compressive or global neurological symptoms. Multidisciplinary care, is essential for patients with PTs, preferably delivered in a center of excellence and based on a well-defined care protocol. In order to facilitate and standardize the clinical procedures for this type of tumor, this document gathers the positioning of the Neuroendocrinology Knowledge Area of the Spanish Society of Endocrinology and Nutrition (SEEN) and the Spanish Society of Neurosurgery (SENEC) on the management of patients with PTs and their preoperative, surgical and postoperative follow-up (AU)

Executive summary of the expert consensus document from the Spanish Society of Neurosurgery and the Spanish Society of Endocrinology and Nutrition: Clinical recommendations on the perioperative management of pituitary tumors.

Pituitary tumors (PT) account for 15% of intracranial tumors affect 10.7%-14.4% of the population although the incidence of clinically relevant PT is 5.1 cases/100,000 inhabitants. Surgical treatment is indicated in PTs with hormone hypersecretion (except for prolactin-producing PTs) and those with local compressive or global neurological symptoms. Multidisciplinary care, is essential for patients with PTs, preferably delivered in a center of excellence and based on a well-defined care protocol. In order to facilitate and standardize the clinical procedures for this type of tumor, this document gathers the positioning of the Neuroendocrinology Knowledge Area of the Spanish Society of Endocrinology and Nutrition (SEEN) and the Spanish Society of Neurosurgery (SENEC) on the management of patients with PTs and their preoperative, surgical and postoperative follow-up.

Hypothalamic and Pituitary Dysfunction After Extensive Brain Surgery: There Is Thirst for More Knowledge.

Craniopharyngiomas are tumors originating from the infundibular stalk, extending to the parasellar and suprasellar region, thereby conferring multiple risks of this region. In particular, hypothalamic and pituitary damage related to its natural history as well as treatment effects of craniopharyngiomas substantially affect life expectancy and quality of life. Here, we describe an adult patient presenting with polyuria, memory, and visual field impairment secondary to concurrent craniopharyngioma and intraventricular glioma. He was treated with surgical resection with postoperative course notable for hypothalamic-pituitary dysfunction, including central hypothyroidism, central adrenal insufficiency, arginine vasopressin deficiency (AVP-D, formerly diabetes insipidus) with loss of sense of thirst, and hypothalamic hypothermia. The adipsia, combined with memory dysfunction, challenged the management of constant fluctuations in his sodium (129-168 mEq/L), with ultimate treatment through vasopressin repletion, fixed fluid intake, strict urine output monitoring, and close counseling of the patient and his caregiver. This case exemplifies the complexity of the endocrine care of patients with craniopharyngiomas and highlights the need for step-wise algorithms in the treatment of hypothalamic deficiencies such as adipsia.

Sellar Suprasellar Surprise: A Rare Case of Atypical Teratoid/Rhabdoid Tumor in an Infant.

We present a case of a 10-month-old male infant who initially presented with polyuria, polydipsia, drowsiness, and fever. Neuroimaging using non-contrast computed tomography (NCCT) demonstrated obstructive hydrocephalus associated with a suprasellar mass, for which emergency neurosurgical intervention was performed with right parietal medium pressure ventriculoperitoneal (MPVP) shunting. For fever, no cause was found with sterile cerebrospinal fluid (CSF) analysis, and empirical antibiotics were administered. The patient exhibited polyuria with hypernatremia and was diagnosed with arginine vasopressin (AVP) deficiency, further complicated by visual impairment due to left optic atrophy. Hormonal workup revealed secondary hypothyroidism and hypocortisolism. Imaging by contrast-enhanced magnetic resonance imaging (CEMR) revealed a lobulated solid-cystic suprasellar mass with flow void, suggestive of adamantinomatous craniopharyngioma initially. However, despite multiple neurosurgical interventions, the patient's condition deteriorated with recurrent fever and seizures, leading to a revision of ventriculoperitoneal shunts. Repeat CEMR showed an increase in the size of the lesion with spinal leptomeningeal metastasis, suggesting a different pathology. Transventricular biopsy confirmed an atypical teratoid and rhabdoid tumor (AT/RT), World Health Organization Classification of Tumors of the Central Nervous System (CNS WHO) grade 4, characterized by diffuse growth pattern, moderate nuclear pleomorphism, clear cytoplasm, and prominent nucleoli. Immunohistochemistry revealed positive vimentin staining and loss of integrase interactor 1 (INI1) expression, consistent with AT/RT. The patient's parents were counseled on the need for multimodal management, including surgery and chemotherapy. However, due to socioeconomic constraints and a guarded prognosis, they chose to leave against medical advice. This case illustrates the diagnostic challenges in distinguishing AT/RT from other suprasellar masses and emphasizes the importance of a multidisciplinary approach in managing complex pediatric cases.

Executive summary of the expert consensus document from the Spanish Society of Neurosurgery and the Spanish Society of Endocrinology and Nutrition: clinical recommendations on the perioperative management of pituitary tumors.

Pituitary tumors (PT) account for 15% of intracranial tumors affect 10.7-14.4% of the population although the incidence of clinically relevant PT is 5.1 cases/100,000 inhabitants. Surgical treatment is indicated in PTs with hormone hypersecretion (except for prolactin-producing PTs) and those with local compressive or global neurological symptoms. Multidisciplinary care, is essential for patients with PTs, preferably delivered in a center of excellence and based on a well-defined care protocol. In order to facilitate and standardize the clinical procedures for this type of tumor, this document gathers the positioning of the Neuroendocrinology Knowledge Area of the Spanish Society of Endocrinology and Nutrition (SEEN) and the Spanish Society of Neurosurgery (SENEC) on the management of patients with PTs and their preoperative, surgical and postoperative follow-up.

Pituitary Stalk Morphology as a Predictor of New-Onset Adrenocortical Insufficiency and Arginine Vasopressin Deficiency after Transsphenoidal Resections of Pituitary Macroadenomas: A Retrospective Single-Center Study with a Focus on iMRI.

BACKGROUND: A new-onset adrenocortical insufficiency (NAI) is the most critical postoperative endocrinological complication after transsphenoidal surgery for macroadenomas. Because of increased mortality risk, arginine vasopressin deficiency (AVP-D) is also a relevant postoperative complication. This study aimed to identify easy-to-acquire magnet resonance imaging (MRI) aspects of the pituitary stalk to predict these insufficiencies after transsphenoidal surgery. METHODS: Pituitary stalk morphology was reviewed intraoperatively and three months postoperatively in the MRIs of 48 transsphenoidal surgeries for macroadenomas. NAI was validated in endocrinological follow-up controls 10-14 months post-surgery. RESULTS: Intraoperative pituitary stalk diameters were 0.5 mm larger in patients who developed NAI and AVP-D. The odds ratio was 29 for NAI and 6 for AVP-D in binary regression analysis. A value of 2.9 mm was identified as the optimal cut-off for the minimal pituitary stalk diameter regarding NAI, with a high specificity of 89%. There was no difference in pituitary stalk diameter regarding these insufficiencies three months post-surgery. CONCLUSIONS: We identified an increased pituitary stalk diameter in intraoperative MRIs as a predictive factor of NAI and AVP-D after transsphenoidal surgery. These findings might improve the early detection of NAI and, thus, optimal management. However, validating these retrospective findings in prospective studies is obligatory.

Diagnostic Accuracy of Copeptin in the Differential Diagnosis of Patients With Diabetes Insipidus: A Systematic Review and Meta-analysis.

OBJECTIVE: Accurate diagnosis of diabetes insipidus (DI) is of significant importance for correct management. We aimed to evaluate the diagnostic accuracy of copeptin level measurements in the differential diagnosis between DI and primary polydipsia (PP). METHODS: A literature search of electronic databases from January 1, 2005, to July 13, 2022, was performed. Primary studies that evaluated the diagnostic accuracy of copeptin concentration in patients with DI and PP were considered eligible. Two reviewers independently screened relevant articles and extracted data. The Quality Assessment of Diagnostic Accuracy Studies 2 tool was used to assess the quality of the included studies. The hierarchical summary receiver operating characteristic model and bivariate method were used. RESULTS: Seven studies including 422 patients with polydipsia-polyuria syndrome were included; of the 422 patients, 189 (44.79%) presented with arginine vasopressin deficiency (AVP-D, cranial DI) and 212 (50.24%) with PP. The summary estimates of the diagnostic performance of stimulated copeptin to differentiate between PP and AVP-D were 0.93 (95% CI, 0.89-0.97) for sensitivity and 0.96 (95% CI, 0.88-1.00) for specificity. Baseline copeptin level showed high performance in identifying AVP resistance (nephrogenic DI), with a pooled sensitivity of 1.00 (95% CI, 0.82-1.00) and specificity of 1.00 (95% CI, 0.98-1.00); however, it showed little value in the differentiation between PP and AVP-D. CONCLUSION: Copeptin level measurement is a useful tool for the differential diagnosis of patients with DI and PP. Stimulation before copeptin measurement is necessary in the diagnosis of AVP-D.

Risk Factors Related to Transient Diabetes Insipidus Development Following Transsphenoidal Pituitary Adenoma Resection: A Multicentric Study.

OBJECTIVE: To analyze and find risk factors associated with developing transient diabetes insipidus (DI) using a multicenter case series after trans-sphenoidal surgery. METHODS: Medical records of patients who underwent trans-sphenoidal surgery for pituitary adenoma resection between 2010 and 2021 at 3 different neurosurgical centers by 4 experienced neurosurgeons were retrospectively analyzed. The patients were divided into 2 groups (DI group or control group). Logistic regression analysis was conducted to identify risk factors associated with postoperative DI. Univariate logistic regression was performed to identify variables of interest. Covariates with a P value <0.05 were incorporated into multivariate logistic regression models to identify independently associated risk factors for DI. All statistical tests were conducted using RStudio. RESULTS: A total of 344 patients were included; 68% were women, the mean age was 46.5 years, and nonfunctioning adenomas were the most frequent (171, 49.7%). The mean tumor size was 20.3 mm. Covariates associated with postoperative DI were age, female gender, and gross total resection. The multivariable model showed that age (odds ratio [OR] 0.97, CI 0.95-0.99, P = 0.017) and female gender (OR 2.92, CI 1.50-6.03, P = 0.002) remained significant predictors of DI development. Gross total resection was no longer a significant predictor of DI in the multivariable model (OR 1.86, CI 0.99-3.71, P = 0.063), suggesting that this variable may be confounded by other factors. CONCLUSIONS: The independent risk factors for the development of transient DI were female and young patients.

Changing the Name of Diabetes Insipidus: A Position Statement of the Working Group for Renaming Diabetes Insipidus.

Recent data show that patients with a diagnosis of diabetes insipidus (DI) are coming to harm. Here we give the rationale for a name change to arginine vasopressin deficiency and resistance for central and nephrogenic DI, respectively.

Disorders of Salt and Water Balance After Pituitary Surgery.

Transsphenoidal surgery is the first-line treatment for many clinically significant pituitary tumors and sellar lesions. Although complication rates are low when performed at high-volume centers, disorders of salt and water balance are relatively common postoperatively. Both, or either, central diabetes insipidus (recently renamed arginine vasopressin deficiency - AVP-D), caused by a deficiency in production and/or secretion of arginine vasopressin, and hyponatremia, most commonly secondary to the syndrome of inappropriate antidiuresis, may occur. These conditions can extend hospital stay and increase the risk of readmission. This article discusses common presentations of salt and water balance disorders following pituitary surgery, the pathophysiology of these conditions, and their diagnosis and management.

A Novel Form of Familial Vasopressin Deficient Diabetes Insipidus Transmitted in an X-linked Recessive Manner.

CONTEXT: Familial pituitary diabetes insipidus has been described only in an autosomal dominant or recessive mode of inheritance. OBJECTIVE: This work aims to determine the cause of a novel form of familial diabetes insipidus (DI) that is controlled by desmopressin therapy but segregates in an X-linked recessive manner. METHODS: Thirteen members from 3 generations of the kindred with familial DI were studied. Water intake, urine volume, urine osmolality, plasma osmolality, and plasma vasopressin were measured under basal conditions, during fluid deprivation, 3% saline infusion, and water loading. Magnetic resonance images of the posterior pituitary also were obtained. In affected males, the effects of desmopressin therapy and linkage of the DI to markers for chromosome Xq28 were determined. In addition, the genes encoding vasopressin, aquaporin-2, the AVPR2 receptor, and its flanking regions were sequenced. RESULTS: This study showed that 4 males from 3 generations of the kindred have DI that is due to a deficiency of vasopressin, is corrected by standard doses of desmopressin, and segregates with markers for the AVPR2 gene in Xq28. However, no mutations were found in AVPR2 or its highly conserved flanking regions. Exome sequencing confirmed these findings and also revealed no deleterious variants in the provasopressin and aquaporin-2 genes. The 4 obligate female carriers osmo-regulated vasopressin in the low normal range. CONCLUSION: X-linked recessive transmission of DI can be due to a defect in either the secretion or the action of vasopressin. Other criteria are necessary to differentiate and manage the 2 disorders correctly.