Antidiuretic hormone deficiency secondary to inactive hydrocephalus: a case report

BACKGROUND

Diabetes insipidus is a syndrome characterized by polyuria, which is almost always associated with polydipsia. The most frequent cause is central diabetes insipidus, which is the result of an inadequate secretion of the antidiuretic hormone, and diagnosis involves differentiating it from other causes of polyuria and polydipsia.

CASE PRESENTATION

Here, we present a clinical case of a previously healthy 13-year-old Nepali boy, who, in December 2022, was found to have intense polydipsia accompanied by polyuria. He had bilateral lower limb weakness at the time of presentation. Biochemical evaluation demonstrated raised serum sodium (181 mEq/L), serum creatinine (78 μmol/L), and serum uric acid (560 μmol/L) with suppressed serum potassium (2.7 mEq/L), which was the major concern to the clinicians. Further laboratory workup revealed an increased serum osmolarity (393.6 mOsm/kg) with reduced urine osmolarity (222.7 mOsm/kg). On contrast magnetic resonance imaging of the brain, a thick-walled third ventricular cyst with bilateral foramen obstruction, thin membrane-like structure at top of aqueduct of Sylvius with gross obstructive hydrocephalus (inactive), and compressed and thinned pituitary gland with no bright spot was observed. The laboratory findings, radiological findings, and case presentation provided the provisional diagnosis of diabetes insipidus due to hydrocephalus and third ventricular cyst.

CONCLUSIONS

Central diabetes insipidus due to hydrocephalus, though rare, can have serious complications including the predilection to develop a deficit of other pituitary hormones. Thus, even if hydrocephalus is dormant with normal intracranial pressure, it must be addressed during investigations of central diabetes insipidus.

Persistent hypernatremia secondary to adipsic central diabetes insipidus in a patient with herpes-induced meningoencephalitis and COVID-19 infection: a case report

Central diabetes insipidus (CDI) typically manifests as a polyuria-polydipsia syndrome, in which normonatremia is generally maintained through the polydipsia. A 53-year-old woman presented with diabetic ketosis and hyperosmolar hyperglycemic syndrome. Her medical history included herpes meningoencephalitis, which was associated with confusion and amnesia. On physical examination, she was apyretic, confused, and had signs of extracellular dehydration. Her capillary glucose concentration was high and her urine was positive for ketones. Laboratory investigations revealed severe hyperglycemia, hypernatremia (plasma hyperosmolarity of 393.6 mOsm/L), and mild acute renal failure. In addition, she had a paucisymptomatic COVID-19 infection. Intravenous rehydration with isotonic saline solution and insulin therapy were effective at controlling the ketosis and ameliorating the hyperglycemia, but failed to normalize the hypernatremia and hyperosmolarity. She was not thirsty and had a urine output of 1 L/day, with urinary hypotonicity. Desmopressin administration reduced the hypernatremia and hyperosmolarity to within their normal ranges, and the patient's urinary osmolarity increased to 743 mOsm/L. Therefore, adipsic CDI was diagnosed. Endocrine investigations revealed isolated central hypothyroidism. The results of pituitary magnetic resonance imaging were normal. Thus, patients with impaired thirst may have an atypical presentation of CDI. In addition, the diagnosis of adipsic CDI is particularly challenging.

Preoperative Serum Copeptin Can Predict Delayed Hyponatremia after Pituitary Surgery in the Absence of Arginine Vasopressin Deficiency

BACKGRUOUND

Delayed postoperative hyponatremia (DPH) is the most common cause of readmission after pituitary surgery. In this study, we aimed to evaluate the cutoff values of serum copeptin and determine the optimal timing for copeptin measurement for the prediction of the occurrence of DPH in patients who undergo endoscopic transsphenoidal approach (eTSA) surgery and tumor resection.

METHODS

This was a prospective observational study of 73 patients who underwent eTSA surgery for pituitary or stalk lesions. Copeptin levels were measured before surgery, 1 hour after extubation, and on postoperative days 1, 2, 7, and 90.

RESULTS

Among 73 patients, 23 patients (31.5%) developed DPH. The baseline ratio of copeptin to serum sodium level showed the highest predictive performance (area under the curve [AUROC], 0.699), and its optimal cutoff to maximize Youden's index was 2.5×10-11, with a sensitivity of 91.3% and negative predictive value of 92.0%. No significant predictors were identified for patients with transient arginine vasopressin (AVP) deficiency. However, for patients without transient AVP deficiency, the copeptin-to-urine osmolarity ratio at baseline demonstrated the highest predictive performance (AUROC, 0.725). An optimal cutoff of 6.5×10-12 maximized Youden's index, with a sensitivity of 92.9% and a negative predictive value of 94.1%.

CONCLUSION

The occurrence of DPH can be predicted using baseline copeptin and its ratio with serum sodium or urine osmolarity only in patients without transient AVP deficiency after pituitary surgery.

Severe osmotic demyelination syndrome with cortical involvement in the context of severe hyponatremia and central diabetes insipidus: an uncommon presentation of an unusual combination

BACKGROUND

Osmotic demyelination syndrome (ODS) with cerebral cortical involvement is a rare complication of severe hyponatremia correction. Careful management of hyponatremia is crucial, particularly in patients with risk factors, such as alcohol use disorder and diabetes insipidus.

CASE

A patient in his 40s with a history of alcohol use disorder and central diabetes insipidus developed ODS after a 24 mEq/L osmolar increase during the treatment of hyponatremia. The patient's condition progressed into locked-in syndrome and then improved to spastic tetraparesis after cortical basal ganglia ODS improved.

DISCUSSION

The differential diagnosis of cortical demyelination includes laminar cortical necrosis, being the interpretation of Apparent Diffusion Coefficient (ADC) MRI sequence is a useful tool.This case underscores the need to investigate and improve diagnosis and treatment strategies in patients with ODS. It also emphasises the significance of careful hyponatremia correction and frequent monitoring, particularly in patients with known risk factors for ODS.

Glucocorticoid impact therapy for recurrent IgG4-related disease with diabetes insipidus as the main manifestation: A case report and literature review

RATIONALE

There is a relative wealth of experience in the initial treatment of IgG4-related disease (IgG4-RD), but little is known about therapeutic measures for recurrent cases combined with multiple organ and tissue involvement.

PATIENT CONCERNS

A 43-year-old man with a previous diagnosis of IgG4-RD due to recurrent right lacrimal gland enlargement with eyelid erythema presented with diabetes insipidus.

DIAGNOSES

We performed a pituitary Magnetic Resonance Imaging which revealed posterior pituitary rim changes with inhomogeneous enhancement and nodular-like thickening of the pituitary stalk, and performed a water-deprivation-vasopressin test confirmed central diabetes insipidus, and in combination with the patient's elevated IgG4 levels and past medical conditions, we diagnosed central diabetes insipidus, IgG4-related hypophysitis, and IgG4-RD.

INTERVENTIONS

After the patient was admitted to the hospital we gave methylprednisolone 500 mg intravenously once daily for 4 days and again for 4 consecutive days after a 10-day interval. During this period combined with mycophenolate mofetil 250 mg twice daily and desmopressin acetate 0.1 mg 3 times daily.

OUTCOMES

The patient was followed up for a sustained period of 6 months and no side effects of glucocorticoid therapy were noted, there were no signs of recurrence, and the daily urine output stabilized in the normal range.

LESSONS

We recognized that IgG4 levels do not reflect relapse or long-term control, and that glucocorticoid shock therapy is an optional and reliable treatment strategy for relapsed patients.

Central Diabetes Insipidus Due to IgG4-related Hypophysitis That Required over One Year to Reach the Final Diagnosis Due to Symptoms Being Masked by Sialadenitis

Pituitary inflammation due to IgG4-related disease is a rare condition and is sometimes accompanied by central diabetes insipidus. Central diabetes insipidus produces a strong thirst sensation, which may be difficult to distinguish when complicated by salivary insufficiency. A 45-year-old man was admitted to our department for a thorough examination of his thirst and polyuria. He had suddenly developed these symptoms more than one year earlier and visited an oral surgeon. Swelling of the left submandibular gland, right parotid gland, and cervical lymph nodes had been observed. Since his IgG4 level was relatively high at 792 mg/dL and a lip biopsy showed high plasmacytoid infiltration around the gland ducts, he had been diagnosed with IgG4-related disease. He had started taking 0.4 mg/kg/day of prednisolone, and his chief complaint temporarily improved. However, since the symptom recurred, he was referred to our institution. After admission, to examine the cause of his thirst and polyuria, we performed a water restriction test, vasopressin loading test, hypertonic saline loading test and pituitary magnetic resonance imaging. Based on the findings, we diagnosed him with central diabetes insipidus due to IgG4-related hypophysitis. We increased the dose of prednisolone to 0.6 mg/kg/day and started 10 μg/day of intranasal desmopressin. His symptoms were subsequently alleviated, and his serum IgG4 level finally normalized. We should remember that IgG4-related disease can be accompanied by hypophysitis and that central diabetes insipidus is brought about by IgG4-related hypophysitis. This case report should remind physicians of the fact that pituitary inflammation due to IgG4-related disease is very rare and can be masked by symptoms due to salivary gland inflammation, which can lead to pitfalls in the diagnosis in clinical practice.

Central diabetes insipidus from a patient's perspective: management, psychological co-morbidities, and renaming of the condition: results from an international web-based survey

BACKGROUND

Central diabetes insipidus is a rare neuroendocrine condition. Data on treatment-associated side-effects, psychological comorbidities, and incorrect management are scarce. The aim of this study was to investigate patients' perspectives on their disease.

METHODS

This study used a cross-sectional, web-based, anonymous survey, developed by endocrinologists and patient representatives, to collect the opinions of patients with central diabetes insipidus on management and complications of their disease, psychological comorbidities, degree of knowledge and awareness of the condition among health-care professionals, and renaming the disease to avoid confusion with diabetes mellitus (diabetes).

FINDINGS

Between Aug 23, 2021, and Feb 7, 2022, 1034 patients with central diabetes insipidus participated in the survey. 91 (9%) participants were children and adolescents (37 [41%] girls and 54 [59%] boys; median age 10 years [IQR 6-15]) and 943 (91%) were adults (757 [80%] women and 186 [20%] men]; median age 44 years [34-54]). 488 (47%) participants had isolated posterior pituitary dysfunction and 546 (53%) had combined anterior and posterior pituitary dysfunction. Main aetiologies were idiopathic (315 [30%] of 1034 participants) and tumours and cysts (pre-surgical 217 [21%]; post-surgical 254 [25%]). 260 (26%; 95% CI [0·23-0·29]) of 994 patients on desmopressin therapy had hyponatraemia leading to hospitalisation. Patients who routinely omitted or delayed desmopressin to allow intermittent aquaresis had a significantly lower prevalence of hyponatraemia compared with those not aware of this approach (odds ratio 0·55 [95% CI 0·39-0·77]; p=0·0006). Of patients who had to be hospitalised for any medical reason, 71 (13%; 95% CI 0·10-0·16) of 535 patients did not receive desmopressin while in a fasting state (nil by mouth) without intravenous fluid replacement and reported symptoms of dehydration. 660 (64%; 0·61-0·67) participants reported lower quality of life, and 369 (36%; 0·33-0·39) had psychological changes subjectively associated with their central diabetes insipidus. 823 (80%; 0·77-0·82) participants encountered a situation where central diabetes insipidus was confused with diabetes mellitus (diabetes) by health-care professionals. 884 (85%; 0·83-0·88) participants supported renaming the disease; the most favoured alternative names were vasopressin deficiency and arginine vasopressin deficiency.

INTERPRETATION

This is the largest survey of patients with central diabetes insipidus, reporting a high prevalence of treatment-associated side-effects, mismanagement during hospitalisation, psychological comorbidities, and a clear support for renaming the disease. Our data are the first to indicate the value of routinely omitting or delaying desmopressin.

FUNDING

Swiss National Science Foundation, Swiss Academy of Medical Sciences, and G&J Bangerter-Rhyner-Foundation.

Central Diabetes Insipidus Following Immunization With BNT162b2 mRNA COVID-19 Vaccine: A Case Report

Introduction

Cases of central diabetes insipidus (CDI) have been reported after COVID-19 infection, with hypophysitis being the most likely cause. COVID-19 vaccines potential adverse effects may mimetize some of these complications.

Case Report

Woman 37 years old, with rheumatoid arthritis under adalimumab (40 mg twice a month) since December 2018. She was in her usual state of health when she has received the second dose of BNT162b2 mRNA COVID-19 vaccine (June 2021). Seven days later, she started reporting intense thirst and polyuria and consulted her family physician.

Blood Analysis

creatinine 0.7 mg/dL, glucose 95mg/dL, Na+ 141mEq/L, K+ 3.9 mEq/L, TSH 3.8 mcUI/L (0.38-5.33), FT4 0.9 ng/dL (0.6-1.1), cortisol 215.4 nmol/L (185-624), ACTH 21.9 pg/mL (6- 48), FSH 4.76 UI/L, LH5.62 UI/L, estradiol 323 pmol/L, IGF1 74.8 ng/mL (88-209), PRL 24.7mcg/L (3.3-26.7) osmolality 298.2 mOs/Kg (250- 325); Urine analysis: volume 10200 mL/24h, osmolality 75 mOs/Kg (300-900), density 1.002. On water restriction test: 0' - Serum osmolality 308.8mOsm/Kg vs. urine osmolality 61.0 mOsm/Kg; 60' - urine osmolality 102 mOsm/Kg; urine osmolality 1 h after desmopressine was 511mOsm/kg. MRI revealed no abnormal signs consistent with hypophysitis except for the loss of the posterior pituitary bright spot on T1 weighted imaging. Diagnosis of CDI was assumed, and started therapy with desmopressine. A report of potential adverse effect was addressed to national health authorities.

Conclusion

In hypophysitis MRI often shows loss of posterior pituitary bright spot on T1 weighted imaging, pituitary enlargement or stalk thickening but those findings were not present in this patient. To the best of our knowledge, CDI has never been reported following administration of a COVID-19 vaccine.

Central Diabetes Insipidus after Syndrome of Inappropriate Antidiuretic Hormone Secretion with Severe Hyponatremia in a Patient with Rathke's Cleft Cyst

A 49-year-old man developed severe hyponatremia associated with transient headache and was diagnosed with syndrome of inappropriate antidiuretic hormone secretion (SIADH). Fluid restriction and sodium supplementation corrected the hyponatremia. However, several days later, the patient exhibited hypernatremia with thirst and polyuria. A detailed examination indicated central diabetes insipidus (CDI) with an intrasellar cystic lesion indicative of Rathke's cleft cyst (RCC). A case of RCC exhibiting headache, hyponatremia, and subsequent hypernatremia has been reported. Our case shows that CDI may appear after SIADH in patients with RCC, especially in those with serum sodium levels that unexpectedly increase rapidly beyond the reference range.

Transcriptomic Analysis Reveals that Activating Transcription Factor 3/c-Jun/Lgals3 Axis Is Associated with Central Diabetes Insipidus after Hypothalamic Injury

BACKGROUND

Hypothalamic injury causes several complicated neuroendocrine-associated disorders, such as water-electrolyte imbalance, obesity, and hypopituitarism. Among these, central diabetes insipidus (CDI), characterized by polyuria, polydipsia, low urine specific gravity, and deficiency of arginine vasopressin contents, is a typical complication after hypothalamic injury.

METHODS

CDI was induced by hypothalamic pituitary stalk injury in male animals. Behavioral parameters and blood sample were collected to evaluate the characteristics of body fluid metabolism imbalance. The brains were harvested for high-throughput RNA sequencing and immunostaining to identify pathophysiological changes in corresponding hypothalamic nuclei.

RESULTS

Based on transcriptomic analysis, we demonstrated the upregulation of the activating transcription factor 3 (Atf3)/c-Jun axis and identified Lgals3, a microglial activation-related gene, as the most significant target gene in response to the body fluid imbalance in CDI. Furthermore, we found that the microglia possessed elevated phagocytic ability, which could promote the elimination of arginine vasopressin neurons after hypothalamic injury.

CONCLUSION

Our findings suggested that the Atf3/c-Jun/Lgals3 axis was associated with the microglial activation, and might participate in the loss of functional arginine vasopressin neurons in CDI after hypothalamic injury.

Grading Central Diabetes Insipidus Induced by Immune Checkpoint Inhibitors: A Challenging Task

Central diabetes insipidus (CDI) is a rare endocrine disease deriving from an insufficient production or secretion of anti-diuretic hormone. Recently, CDI has been reported as a rare side effect triggered by immune checkpoint inhibitors (ICI) in cancer patients. Despite its current rarity, CDI triggered by ICI is expected to affect an increasing number of patients because of the expanding use of these effective drugs in a growing number of solid and hematologic malignancies. An appropriate assessment of the severity of adverse events induced by anticancer agents is crucial in their management, including dosing adjustment and temporary withdrawal or discontinuation treatment. However, assessment of the severity of CDI induced by ICI may be challenging, as its main signs and symptoms (polyuria, dehydration, weight loss, and hypernatremia) can be incompletely graded. Indeed, the current grading system of toxicity induced by anticancer treatments does not include polyuria. Additionally, dehydration in patients affected by diabetes insipidus, including ICI-induced CDI, is different in certain aspects from that due to other conditions seen in cancer patients, such as vomiting and diarrhea. This prompted us to reflect on the need to grade polyuria, and how to grade it, and to consider a specific grading system for dehydration associated with CDI induced by ICI. Here we propose a new grading system for polyuria and dehydration, as critical symptoms of the CDI syndrome occurring in patients on ICI treatment, to obtain better management of both the adverse event and the triggering drugs.

Management of transient central diabetes insipidus with intravenous desmopressin in a premature infant with gastroschisis and septo-optic dysplasia: A case report

Central diabetes insipidus (CDI) may occur in the setting of intracranial abnormalities that affect the hypothalamus-pituitary system. It occurs rarely in neonates, especially in the premature population, and represents a challenging disease process to treat pharmacologically. Little is known regarding the treatment options in premature infants, including dose and route of administration of intravenous desmopressin (DDAVP). We present a case of a late premature male infant with gastroschisis and septo-optic dysplasia who developed transient CDI. He was treated with intravenous DDAVP but required frequent laboratory monitoring and a multidisciplinary approach, and ultimately his CDI resolved. Although there are minimal guidelines regarding the appropriate formulation and dosage of DDAVP for management of CDI in infants, we initiated the lowest dose available and titrated the medication based on close monitoring of urine output and serum sodium levels in order to successfully treat his transient CDI.

Lower Oxytocin Levels Are Associated with Lower Bone Mineral Density and Less Favorable Hip Geometry in Hypopituitary Men

INTRODUCTION

Hypopituitary patients are at risk for bone loss. Hypothalamic-posterior pituitary hormones oxytocin and vasopressin are anabolic and catabolic, respectively, to the skeleton. Patients with hypopituitarism may be at risk for oxytocin deficiency. Whether oxytocin and/or vasopressin contribute to impaired bone homeostasis in hypopituitarism is unknown.

OBJECTIVES

To determine the relationship between plasma oxytocin and vasopressin levels and bone characteristics (bone mineral density [BMD] and hip structural analysis [HSA]) in patients who have anterior pituitary deficiencies only (APD group) or with central diabetes insipidus (CDI group).

METHODS

This is a cross-sectional study. Subjects included 37 men (17 CDI and 20 APD), aged 20-60 years. Main outcome measures were fasting plasma oxytocin and vasopressin levels, and BMD and HSA using dual X-ray absorptiometry.

RESULTS

Mean BMD and HSA variables did not differ between the CDI and APD groups. Mean BMD Z-scores at most sites were lower in those participants who had fasting oxytocin levels below, rather than above, the median. There were positive associations between fasting oxytocin levels and (1) BMD Z-scores at the spine, femoral neck, total hip, and subtotal body and (2) favorable hip geometry and strength variables at the intertrochanteric region in CDI, but not APD, participants. No associations between vasopressin levels and bone variables were observed in the CDI or ADP groups.

CONCLUSIONS

This study provides evidence for a relationship between oxytocin levels and BMD and estimated hip geometry and strength in hypopituitarism with CDI. Future studies will be important to determine whether oxytocin could be used therapeutically to optimize bone health in patients with hypopituitarism.

Permanent diabetes insipidus in a patient with mesothelioma treated with immunotherapy

Checkpoint inhibitors have substantially improved the prognosis for patients with advanced malignancy. Treatment with immunomodulants has the ability to reactivate the immune system against tumor cells, but can also trigger the development of immune-related adverse events that reflects a loss of tolerance of the immune system for self-antigens. Regarding the endocrine system, thyroid and pituitary are the most frequent glands involved; in particular hypophysitis is commonly observed with anti-CTLA4 with a variable impaired anterior pituitary dysfunction (mainly ACTH and TSH dysregulation) while a posterior pituitary dysfunction has been rarely described. A 68-year-old man with a diagnosis of metastatic mesothelioma started in September 2016 first-line treatment with tremelimumab and durvalumab. After 3 cycles he presented sudden onset of polydipsia and polyuria without other symptoms. Diagnostic work-up, including a water deprivation test, established a diagnosis of central diabetes insipidus. Patient started sublingual desmopressin 60 mcg three times a day, that was subsequently increased up to 480 mcg/die. At magnetic resonance imaging the posterior lobe of pituitary gland did not show high signal intensity on T1-weighted images. After regression of diabetes insipidus symptoms under desmopressin, patient restarted cancer treatment and received additional 10 doses without worsening of endocrinological toxicity or further treatment-related toxicities, maintaining the same desmopressin dosage. Posterior pituitary dysfunction has been rarely observed in patients treated with immunomodulants. To our knowledge, this is the first observation of permanent central diabetes insipidus in patients treated with combined immune checkpoint inhibitors (tremelimumab and durvalumab).

ENDOCRINOLOGY IN THE TIME OF COVID-19: Management of diabetes insipidus and hyponatraemia

COVID-19 has changed the nature of medical consultations, emphasizing virtual patient counseling, with relevance for patients with diabetes insipidus (DI) or hyponatraemia. The main complication of desmopressin treatment in DI is dilutional hyponatraemia. Since plasma sodium monitoring is not always possible in times of COVID-19, we recommend to delay the desmopressin dose once a week until aquaresis occurs allowing excess retained water to be excreted. Patients should measure their body weight daily. Patients with DI admitted to the hospital with COVID-19 have a high risk for mortality due to volume depletion. Specialists must supervise fluid replacement and dosing of desmopressin. Patients after pituitary surgery should drink to thirst and measure their body weight daily to early recognize the development of the postoperative syndrome of inappropriate antidiuresis (SIAD). They should know hyponatraemia symptoms. The prevalence of hyponatraemia in patients with pneumonia due to COVID-19 is not yet known, but seems to be low. In contrast, hypernatraemia may develop in COVID-19 patients in ICU, from different multifactorial reasons, for example, due to insensible water losses from pyrexia, increased respiration rate and use of diuretics. Hypernatraemic dehydration may contribute to the high risk of acute kidney injury in COVID-19. IV fluid replacement should be administered with caution in severe cases of COVID-19 because of the risk of pulmonary oedema.

Clinical Characteristics of Pediatric Patients With Sellar and Suprasellar Lesions Who Initially Present With Central Diabetes Insipidus: A Retrospective Study of 55 Cases From a Large Pituitary Center in China

Purpose: To increase knowledge for the early differential diagnosis and accurate therapeutic strategies for pediatric patients with sellar or suprasellar region (SSR) lesions who initially present with central diabetes insipidus (CDI). Methods: This is a retrospective review of 55 pediatric patients (≤14 years old) with identified lesions in the SSR who initially presented with CDI at a large pituitary center between 2012 and 2018. The following data were summarized: demographic, clinical, endocrine, and neuroimaging data, intraoperative findings, histopathological findings, treatments, and prognosis. Results: In our group, the etiologies of the SSR lesions included germ cell tumors (GCTs, 74.5%), Langerhans cell histiocytosis (LCH, 18.2%), and craniopharyngioma (CP, 7.3%). Almost all patients (50/55, 90.9%) showed anterior pituitary dysfunction [multiple axes dysfunction (38), and isolated axis dysfunction (14)], while the GH/IGF-I axis was the most affected. Most GCT patients presented with various clinical manifestations besides CDI and had elevated β-HCG, whereas LCH and CP patients mostly presented few non-specific symptoms besides CDI and most had normal level tumor markers. Sellar MRI demonstrated that posterior pituitary bright spot disappearance occurred in all patients, and pituitary stalk thickening was observed in 96.7% of patients. Treatment varied due to the different etiologies of the SSR lesions. After follow-up for 35.4 ± 20.2 months, the proportions of patients who needed AVP (arginine vasopressin) for GCT, LCH, and CP were 86.5, 100, and 75%, respectively, and the proportions of patients who needed HRT were 89.2, 50, and 75%, respectively. Conclusion: For pediatric SSR lesions that first manifest as CDI, we should comprehensively consider clinical characteristics and imaging features to aid in their early differential diagnosis. Tumor markers and surgical histopathology are also great complements for the differential diagnosis. Additionally, various treatment strategies should be adopted according to different causes to improve the child's prognosis and quality of life.

ADHD symptoms in a young patient with central diabetes insipidus

Diabetes insipidus is known to be associated with neurodevelopmental disorders. In this case report, we present a child suffering from a central diabetes insipidus (DI) and an attention-deficit/hyperactivity disorder (ADHD). The DI was due to a mutation on the vasopressin gene, impairing its secretion. We discuss the effects of this impairment on the central nervous system and how it might be linked to ADHD symptoms.

A challenging coexistence of central diabetes insipidus and cerebral salt wasting syndrome: a case report

BACKGROUND

Combined central diabetes insipidus and cerebral salt wasting syndrome is a rare clinical finding. However, when this happens, mortality is high due to delayed diagnosis and/or inadequate treatment.

CASE PRESENTATION

A 42-year-old white man was referred to neurosurgery due to a non-functional pituitary macroadenoma. He underwent a partial resection of the tumor on July 2, 2015. On the day following surgery he presented polyuria with sodium 149 mEq/L, plasma osmolality 301 mOsm/kg, and urine osmolality 293 mOsm/kg. He started nasal desmopressin 0.05 mg/day with good response. He was already on dexamethasone 4 mg and levothyroxine 75 mcg due to hypopituitarism after surgery. On July 9 he became confused. Cerebral computed tomography was performed with no significant changes. His natremia dropped to 128 mEq/L with development of polyuria despite maintenance of desmopressin dose. His hemoglobin and hematocrit rose from 9.1 g/L to 11.6 g/L and 27.5 to 32.5, respectively. His thyroid function was normal and he was on hydrocortisone 30 mg/day. At 12 p.m. 150 mg/hydrocortisone infusion was initiated, but sodium did not increase. Plasma and urine osmolality were 264 mOsm/kg and 679 mOsm/kg, respectively. At 4 p.m. hydrocortisone was increased and hypertonic saline replacement started. Two hours later he was dehydrated with polyuria and vomiting, and natremia of 124 mEq/L. Hyponatremia was very resistant to treatment despite hypertonic saline replacement, hence desmopressin was suspended. The following day, urine spot analysis showed that natriuresis was 63 mEq/L with serum sodium 132 mEq/L. This was interpreted as a cerebral salt wasting syndrome and control was achieved with aggressive hypertonic saline replacements and fludrocortisone 0.1 mg/three times a day.

CONCLUSIONS

We present a rare case of a patient with diabetes insipidus and cerebral salt wasting syndrome, who was successfully treated. Hyponatremia in a patient with diabetes insipidus may erroneously be interpreted as inadequate diabetes insipidus control or as syndrome of inappropriate antidiuretic hormone secretion, leading to therapeutic errors. Thus, all clinical and analytical data should be evaluated together for early and correct diagnosis.

Manifestation of Central Diabetes Insipidus in a Patient with Thyroid Storm

We herein report a case of central diabetes insipidus complicated with thyroid storm. A middle-aged woman who was receiving treatment for Graves' disease suddenly complained of polydipsia, polyuria and general fatigue. Laboratory tests showed hyperthyroidism, hypernatremia, hypoosmolar urine and a decreased plasma vasopressin level. The occurrence of central diabetes insipidus with hyperthyroidism was revealed on the basis of pituitary magnetic resonance imaging, a water deprivation test and a desmopressin test. The clinical co-existence of diabetes insipidus and hyperthyroidism is very rare; however, the complication should be considered when hypernatremia and/or dehydration progress in patients with Graves's disease as a common autoimmune-related etiology.

Cardiovascular autonomic dysfunction in patients with idiopathic diabetes insipidus

INTRODUCTION

Central diabetes insipidus (DI) is a rare disease characterized by the excretion of excessive volumes of dilute urine due to reduced levels of the antidiuretic hormone arginine vasopressin (AVP), caused by an acquired or genetic defect in the neurohypophysis. The aim of this study was to identify any autonomic dysfunction (AD) in patients with DI as a possible cofactor responsible for their reportedly higher mortality.

METHODS

The study involved 12 patients (6 females) with central idiopathic DI and a well-controlled electrolyte balance, and 12 controls matched for age, sex and cardiovascular risk factors, who were assessed using the tilt, lying-to-standing, hand grip, deep breath, Valsalva maneuver and Stroop tests.

RESULTS

The tilt test showed a significantly more pronounced decrease in both systolic (- 20.67 ± 18 vs. - 1.92 ± 6.99 mmHg, p = 0.0009) and diastolic blood pressure (- 10.5 ± 14.29 vs. - 1.5 ± 5 mmHg, p = 0.012) in patients than in controls. Three patients with DI had to suspend the test due to the onset of syncope. The lying-to-standing test also revealed a marked reduction in blood pressure in patients with DI (1.05 ± 0.13 vs. 1.53 ± 0.14, p = 0.0001). Similar results emerged for the Valsalva maneuver (Valsalva ratio, 1.24 ± 0.19 vs. 1.79 ± 0.11, p < 0.0001) and deep breath test (1.08 ± 0.11 vs. 1.33 ± 0.08, p < 0.0001).

CONCLUSIONS

All the principal autonomic tests performed in the study were concordant in indicating that patients with central DI have an impaired autonomic nervous system function despite a normal hydroelectrolytic balance under desmopressin therapy. This impairment may reflect damage to the autonomic system per se and/or the absence of any vasoactive effect of AVP on vascular smooth muscle. In our opinion, patients with central DI should be educated on how to prevent orthostatic hypotension, and pharmacological treatment should be considered for patients with a more marked impairment.

[Association between central diabetes insipidus and type 2 diabetes mellitus]

Central diabetes insipidus is a rare disease of the hypothalamus and neurohypophysis. It is very unusually found in the adult with type 2 diabetes mellitus. It is manifested by a polydipsic polyuric syndrome, which must be distinguished from the poorly controlled type 2 diabetes mellitus. Given the similarity of both entities and the unusual nature of their coexistence, their suspicion is difficult. The case of a 72-year-old male with type 2 diabetes mellitus with poor insulin control (fasting hyperglycemia greater than 180 mg/dl) who had a long-standing polyuric syndrome is here presented. Hypernatremia and plasma osmolality elevated together with a low urinary osmolality led to the suspicion of diabetes insipidus, which was subsequently confirmed by the dehydration test and the administration of desmopressin sc. With 61% increase in the calculated urinary osmolarity one hour post desmopressin s.c., diabetes insipidus of central type was diagnosed. Nuclear Magnetic Resonance showed a bright spot with normal neurohypophysis, contributing to the diagnosis of the idiopathic form.

The central diabetes insipidus associated with septo-optic dysplasia (de Morsier syndrome)

INTRODUCTION

Septo-optic dysplasia (SOD) is a rare congenital heterogeneous malformation with postulated genetic and environmental etiology. Septo-optic dysplasia is characterized by classic triad: optic nerve hypoplasia, midline brain malformation and hypothalamic-pituitary endocrine deficiencies. The most common hormonal deficiencies affect growth hormone and gonadotropin but it can also be lower levels of the other hormones. The rarest form of hormone deficiency is the deficiency of the antidiuretic hormone.

CASE REPORT

The boy was born in 39th week of pregnancy in general good condition. Weakened suction reflex and spitting resulted in substantial difficulties with breastfeeding. After transfontanelle ultrasonography central nervous system defect was suspected. In the 5th month of life MRI confirmed septo-optic dysplasia on the basis of anterior genu of corpus callosum and septum pellucidum agenesis, both optic nerves and optic chiasm hypoplasia, pachygyria and polimicrogyria of the right frontoparietal cortex. Neurological examination revealed axial laxity, psychomotor development delay, difficulties in keeping eyes fixed as well as rotary and horizontal nystagmus. At the age of 3 years he underwent the endocrinological consultation due to polydipsia and polyuria. The tests revealed lower urine specific gravity tests results, therefore diabetes insipidus was diagnosed. The boy still receives desmopressin and there are no signs of central diabetes insipidus. Currently, the boy is under a multi-disciplinary medical care.

CONCLUSIONS

The attention should be focussed on early diagnosis, mutli-specialized care and treatment SOD. Hypopituitarism ranges from isolated to multiple hormone deficits, with diabetes insipidus in a minority. Although rare, SOD is an important cause of congenital hypopituitarism and should be considered in all children with midline defects and optic nerve hyploplasia.

Primary lymphocytic hypophysitis: Clinical characteristics and treatment of 50 cases in a single centre in China over 18 years

OBJECTIVE

Primary lymphocytic hypophysitis (LYH) is rare, and it is often evaluated in a small case series. This study aimed to describe the diagnosis and treatment of primary LYH in a larger cohort.

DESIGN

A retrospective study of the diagnosis and treatment of primary LYH was conducted at Peking Union Medical College Hospital from 1999 to 2016.

PATIENTS

Fifty patients (28 histologically diagnosed and 22 clinically-diagnosed) were eligible for inclusion.

MEASUREMENTS

Clinical, endocrine, pathological and imaging findings; therapies and outcomes were assessed. Ordinal logistic regression analysis was used to evaluate the association between the clinical parameters and outcomes (eg, improvements in pituitary function, regression of lesion size on MRI and disease recurrence).

RESULTS

Central diabetes insipidus (CDI) (72.0%) was the most common endocrine dysfunction. Hypogonadotropic hypogonadism was the most frequently observed (60.0%) manifestation of anterior pituitary dysfunction; adrenal insufficiency was the third most common (26.0%) manifestation; and IGF-1 axis defects were the least frequent (22.0%). Thickening of the pituitary stalk was the most frequent (96.0%) imaging finding, and 78.0% of the patients exhibited both intrasellar and suprasellar expansion. Pharmacological dose of glucocorticoids was identified to be significantly associated with increased odds of anterior pituitary function improvement. No observed covariates were significantly associated with improvement of CDI and recurrence.

CONCLUSION

The sequence of anterior pituitary deficiencies in Chinese primary LYH patients was atypical (LH/FSH>TSH>ACTH>IGF-1 axis deficiency). A pharmacological dose of glucocorticoids was significantly associated with the improved anterior pituitary insufficiency.

Clinical presentation and outcome of children with central diabetes insipidus associated with a self-limited or transient pituitary stalk thickening, diagnosed as infundibuloneurohypophysitis

OBJECTIVE

Despite lymphocytic or autoimmune infundibuloneurohypophysitis (INH) is an increasingly recognized aetiology in children with central diabetes insipidus (CDI); clinical data on epidemiology (clinical evolution, predisposing factors, complications), diagnosis and management of this entity are limited and mostly based on published case reports. The aim of this study was to gain a broader insight in the natural history of this disease by analysing the clinical presentation, radiological pituitary stalk changes, associated autoimmunity and hormonal deficiencies in children with CDI and a self-limiting or transient stalk thickening (ST), diagnosed as autoimmune infundibuloneurohypophysitis, during the last 15 years in four Belgian university hospitals.

DESIGN AND PATIENTS

The medical files of nine CDI patients with a ST at initial presentation and no signs of Langerhans cell histiocytosis or germinoma at presentation and/or during follow-up of more than 1.5 years were reviewed.

RESULTS

Age at presentation ranged from 3 to 14 years. Two patients had a positive family history of autoimmunity. Three children presented with associated growth failure, two with nausea and one with long-standing headache. Median maximal diameter of the stalk was 4.6 mm (2.7-10 mm). Four patients had extra-pituitary brain anomalies, such as cysts. One patient had central hypothyroidism, and another had a partial growth hormone deficiency at diagnosis. Within a mean follow-up of 5.4 (1.5-15) years, stalk thickening remained unchanged in two patients, regressed in one and normalized in six children. CDI remained in all, while additional pituitary hormone deficiencies developed in only one patient.

CONCLUSIONS

In this series of children INH with CDI as initial presentation, CDI was permanent and infrequently associated with anterior pituitary hormone deficiencies, despite a frequent association with nonstalk cerebral lesions.

Heterogenous patterns of recovery of thirst in adult patients with adipsic diabetes insipidus

BACKGROUND

The natural history of adipsic diabetes insipidus (ADI) is not well described, and reports of recovery of thirst are rare.

DESIGN AND METHODS

Case histories presentation. ADI was identified by demonstrating absent thirst and arginine vasopressin (AVP) responses to hypertonic saline infusion.

RESULTS

Twelve patients with ADI were identified (craniopharyngioma 5, anterior communicating artery aneurysm (ACOM) repair 4, congenital 1, neurosarcoidosis 1, prolactinoma 1). Three patients died. Six patients had permanent ADI. Three patients had recovery of thirst, with a heterogenous pattern of recovery. In the first case, ADI had developed after clipping of an ACOM aneurysm. Ten years after surgery; he sensed the return of thirst; repeated hypertonic saline infusion showed recovery of thirst and AVP secretion. In the second case, a 41-year-old female with an intrasellar craniopharyngioma developed post-operative ADI with persistent hypernatremia. Two years post-operatively, she complained of thirst, and hypertonic saline infusion showed normalization of thirst but absent AVP responses, confirming recovery of thirst, but with persistent diabetes insipidus (DI). In the third case, a 29-year-old Caucasian had craniotomy and radiotherapy for craniopharyngioma and developed ADI post-operatively. Eight years post-op, she presented with thirst, seizures and pNa of 112 mmol/l. Hypertonic saline infusion showed persistent DI but thirst responses typical of compulsive water drinking; she has had recurrent hyponatraemia since then.

CONCLUSIONS

We report that 3/12 patients with ADI recovered thirst after longstanding adipsia with heterogenous pattern of recovery. Both the mortality of 25% and the recovery rate of 25% should be considered when planning long-term surveillance.

Central Diabetes Insipidus in Infancy With or Without Hypothalamic Adipsic Hypernatremia Syndrome: Early Identification and Outcome

CONTEXT

Neonatal central diabetes insipidus (CDI) with or without adipsia is a very rare complication of various complex hypothalamic disorders. It is associated with greater morbidity and a high risk of developing both hypernatremia and hyponatremia, due to the condition itself or secondary to treatment with vasopressin analogs or fluid administration. Its outcomes have yet to be evaluated.

OBJECTIVE

To investigate the clinical outcomes of patients with neonatal-onset CDI or adipsic CDI with hypernatremia.

DESIGN, SETTING, AND PARTICIPANTS

All patients diagnosed with neonatal CDI in a university hospital-based observational study and followed between 2005 and 2015 were included and analyzed retrospectively.

MAIN OUTCOME MEASURES

The various causes of CDI were grouped. Clinical outcome and comorbidities were analyzed.

RESULTS

Ten of the 12 patients had an underlying condition with brain malformations: optic nerve hypoplasia (n = 3), septo-optic dysplasia (n = 2), semilobar holoprosencephaly (n = 1), ectopic neurohypophysis (n = 3), and unilateral absence of the internal carotid artery (n = 1). The other two were idiopathic cases. During the median follow-up period of 7.8 (4.9-16.8) years, all but one patient displayed anterior pituitary deficiency. Transient CDI was found in three (25%) patients for whom a posterior pituitary hyperintense signal was observed with (n = 2) and without (n = 1) structural hypothalamic pituitary abnormalities, and with no other underlying cerebral malformations. Patients with permanent CDI with persistent adipsia (n = 4) and without adipsia (n = 5) required adequate fluid intake and various doses of desamino-D-arginine-8-vasopressin. Those with adipsia were more likely to develop hypernatremia (45 vs 33%), hyponatremia (16 vs 4%) (P < .0001), and severe neurodevelopmental delay (P < .05) than those without adipsia. Comorbidities were common. The underlying cause remains unknown at the age of 23 years for one patient with CDI and normal thirst.

CONCLUSION

Neonatal CDI may be transient or permanent. These vulnerable patients have high rates of comorbidity and require careful monitoring.

Diagnostic Accuracy of Copeptin in the Differential Diagnosis of the Polyuria-polydipsia Syndrome: A Prospective Multicenter Study

CONTEXT

The polyuria-polydipsia syndrome comprises primary polydipsia (PP) and central and nephrogenic diabetes insipidus (DI). Correctly discriminating these entities is mandatory, given that inadequate treatment causes serious complications. The diagnostic "gold standard" is the water deprivation test with assessment of arginine vasopressin (AVP) activity. However, test interpretation and AVP measurement are challenging.

OBJECTIVE

The objective was to evaluate the accuracy of copeptin, a stable peptide stoichiometrically cosecreted with AVP, in the differential diagnosis of polyuria-polydipsia syndrome.

DESIGN, SETTING, AND PATIENTS

This was a prospective multicenter observational cohort study from four Swiss or German tertiary referral centers of adults >18 years old with the history of polyuria and polydipsia.

MEASUREMENTS

A standardized combined water deprivation/3% saline infusion test was performed and terminated when serum sodium exceeded 147 mmol/L. Circulating copeptin and AVP levels were measured regularly throughout the test. Final diagnosis was based on the water deprivation/saline infusion test results, clinical information, and the treatment response.

RESULTS

Fifty-five patients were enrolled (11 with complete central DI, 16 with partial central DI, 18 with PP, and 10 with nephrogenic DI). Without prior thirsting, a single baseline copeptin level >21.4 pmol/L differentiated nephrogenic DI from other etiologies with a 100% sensitivity and specificity, rendering a water deprivation testing unnecessary in such cases. A stimulated copeptin >4.9 pmol/L (at sodium levels >147 mmol/L) differentiated between patients with PP and patients with partial central DI with a 94.0% specificity and a 94.4% sensitivity. A stimulated AVP >1.8 pg/mL differentiated between the same categories with a 93.0% specificity and a 83.0% sensitivity.

LIMITATION

This study was limited by incorporation bias from including AVP levels as a diagnostic criterion.

CONCLUSION

Copeptin is a promising new tool in the differential diagnosis of the polyuria-polydipsia syndrome, and a valid surrogate marker for AVP. Primary Funding Sources: Swiss National Science Foundation, University of Basel.

Central diabetes insipidus: alert for dehydration in very low birth weight infants during the neonatal period. A case report

CONTEXT

Central diabetes insipidus (CDI) is a rare cause of hypernatremia during the neonatal period. The diagnosis is particularly difficult in very low birth weight (VLBW) newborns.

CASE REPORT

We report on a preterm newborn who presented CDI soon after birth. On the third day of life, signs of dehydration were present despite normal fluid supply. The diuresis rate was 4.4 ml/kg/h. Although the fluid supply was then increased, the dehydration continued, with hypernatremia, normal glycemia, diuresis of 7.4 ml/kg/h and urine density of 1005 mOsmol/l. Thus, a diagnostic hypothesis of diabetes insipidus was raised. A test with a nasal vasopressin analogue (dDAVP) was performed and CDI was confirmed. Reduction of the fluid supply became possible through appropriate treatment.

CONCLUSION

The diagnosis of CDI is rarely made during the neonatal period, especially in VLBW newborns, because of the difficulty in detecting elevated diuresis. Persistent hypernatremia, usually accompanied by hyperthermia despite abundant fluid supply, weight loss and low urine osmolality are important signs of alert.

Secondary nocturnal enuresis related to central diabetes insipidus as an early manifestation of intracranial germinomatous germ cell tumors in a series of male youngsters

Nocturnal enuresis is a common symptom in children. It is usually attributed to benign causes and diagnostic evaluation is not carried out. We report three male young patients initially presenting with short stature and nocturnal enuresis, related to diabetes insipidus, caused by intracranial germinomatous germ cell tumors. In all three cases, water deprivation tests confirmed diabetes insipidus. Extensive endocrinological investigation also showed further hormone deficiencies. Magnetic resonance imaging of the brain revealed the presence of a central nervous system lesion and histology confirmed the final diagnosis. Surgery, radiation with or without chemotherapy was conducted and the patients were treated with hormone replacement therapies. The patients after a long follow-up were free of disease. We present these cases to alert clinicians to bear in mind that the presence of an intracranial germinomatous germ cell tumor should at least be considered in a child presenting with bed wetting, especially if additional symptoms and signs, including late onset puberty and growth delay or morning hypernatremia, may coexist.

Management of central diabetes insipidus with oral desmopressin lyophilisate in infants

AIM

To assess the efficiency of oral desmopressin lyophilisate (ODL) in neonatal central diabetes insipidus (CDI).

METHODS

The characteristics of four newborns with CDI treated with ODL were evaluated.

RESULTS

Four newborns with polyuria and hypernatremia were included [male, 2 (50%); mean postnatal age, 19±17 days]. At the time of hypernatremia, the mean serum and urine osmolality values were 310±16 and 179±48 mOsm/kg, respectively. Antidiuretic hormone levels were undetectable (<0.5 pmol/L) in all cases. Magnetic resonance imaging revealed anatomical malformations in all cases. ODL (60 μg/tablet) dissolved in water (3-5 mL) was initiated with a dose of 5 μg/kg/day in two equal doses, together with limitation of water intake to avoid hyponatremia. Serum sodium levels returned to normal in a mean duration of 58±9.9 h with a mean decline rate of 0.37±0.1 mEq/L/h after desmopressin administration. Rehospitalization was required for one of the infants because of hypernatremia due to non-compliance. No episode of hyponatremia was encountered. Weight gain and growth of the infants were normal during the mean follow-up duration of 8.5±1 months.

CONCLUSIONS

ODL appears to be practical and safe in the treatment of CDI during the first year of life.

[A case of possible immunoglobulin G4-related disease (IgG4-RD) with retroperitoneal fibrosis and central diabetes insipidus due to infundibulohypophysitis]

We report a case of possible immunoglobulin G4-related disease(IgG4-RD)that resulted in complications such as retroperitoneal fibrosis and infundibulohypophysitis. The patient was a 72-year-old male who presented with polyuria and polydipsia. Magnetic resonance imaging(MRI)revealed a thickened pituitary stalk and contrast enhancement with gadolinium. T1-weighted imaging revealed that the posterior pituitary high-signal zone had disappeared. Central diabetes insipidus was diagnosed on the basis of results of the hypertonic saline test. In addition, pressure due to retroperitoneal fibrosis resulted in hydronephrosis and elevated serum IgG4 levels. Because it was determined that the patient could have IgG4-RD, he was administered prednisolone, following which a decrease in the size of the pituitary stalk and retroperitoneal fibrosis was observed. IgG4-RD is characterized by elevated serum IgG4 levels and the infiltration of IgG4-positive plasma cells into various organs, including the central nervous system. Recently, IgG4-RD research teams organized by the Ministry of Health, Labour and Welfare established guidelines for the diagnosis of IgG4-RD. According to these guidelines, this case would fall under the category of "possible IgG4-RD." This case suggested that when infundibulohypophysitis is detected by neuroradiology, further investigation into the possibility of IgG4-RD should be recommended.

Draining the edema: a new role for aquaretics?

Investigations into edema formation in nephrotic syndrome have mostly focused on the primary role of sodium. While there is controversy about whether sodium retention is an inherent aspect of nephrotic syndrome (overfill hypothesis) or a secondary consequence (underfill hypothesis), the critical role of sodium in driving fluid retention is generally accepted. Consequently, treatment of edema is based on enhancing renal sodium excretion, using saluretics to block tubular reabsorption of sodium. However, there is also evidence of renal water retention: urine in nephrotic patients is typically highly concentrated (unless urinary concentrating ability is impaired by loop diuretics), and vasopressin levels are commonly elevated. Consequently, aquaretics, i.e., drugs that inhibit renal water reabsorption, may constitute effective treatments for nephrotic edema. In fact, these drugs are already approved for the treatment of non-nephrotic edematous states, such as those encountered in congestive heart or liver failure. In this edition of Pediatric Nephrology, two case reports raise the possibility that aquaretics may also be helpful in the treatment of nephrotic edema. These case reports provide no solid evidence for such treatment, and there clearly are serious concerns about inducing critical hypovolemia with potentially catastrophically consequences, such as thrombosis and shock. Yet these concerns similarly apply to saluretics, which clinicians routinely use in the treatment of edema. In addition, the described powerful effect of aquaretics with respect to the resolution of edema, as well as our understanding of the underlying physiology, argue for a more systematic, yet careful assessment of these drugs in the treatment of nephrotic syndrome.

[PET-CT documented complete remission of Erdheim-Chester disease, lasting more than 4 years from treatment initiation with cladribine]

Erdheim-Chester disease is a very rare histiocytic disease. It represents one form of juvenile xanthogranuloma in WHO classification of blood diseases. The disease often causes B symptoms, skeletal pain and also may cause diabetes insipidus and retroperitoneal fibrosis. Selection of therapy depends on published case reports and small clinical trials. There are no recommendations for treatment based on randomized studies. Interferon α is probably the most commonly used drug for this disease. Some remissions have been described after treatment. However, long-term interferon α application is needed which is associated with numerous side effects. There are limited experiences with clabridine in this indication. In Pubmed Medline database, we have found 3 publications dedicated to description of treatment response after cladribine in Erdheim-Chester disease and other 7 papers evaluating effect of cladribine on juvenile xanthogranuloma forms, mostly with positive outcome. Based on these 10 publications we choose cladribine as first-line treatment in our patient. The treatment started in October 2009 with combination of 2-chlorodeoxyadenosine (Litak) 5 mg/m2 sc. + cyclophosphamide 150 mg/m2 iv. + dexamethasone 24 mg iv., five days consecutively. These cycles were repeated monthly. Mentioned formula was submitted 4 times and 3 times in limited application on day 1 - 3. The reason of that was neutropenia grade 3. All symptoms disappeared after treatment. Only diabetes insipidus persisted because damage of pituitary stalk is irreversible. Therapeutic effect was monitored by PET-CT imaging, initially every 6 months, later in 12-month intervals. PET-CT imaging showed complete remission of disease and 4.5 years duration of remission after treatment. The treatment was well tolerated with no complications implying hospitalization. Only mild thrombocytopenia and neutropenia remains after 4.5 years. Based on case report and publications we consider cladribine as appropriate firs-line drug for Erdheim-Chester disease. Therapeutic failure after 3-4 cycles may suggest other options (interferon α, anakinra, vemurafenib), but only in the case if healthcare provider is willing to cover this new and more expansive treatment than therapy with cladribine.

Adipsia increases risk of death in patients with central diabetes insipidus

Central diabetes insipidus (CDI) is caused by deficiency of arginine vasopressin, an antidiuretic hormone. Patients with CDI manifest polyuria which is usually compensated for by increases in water intake. However, some patients are not able to sense thirst due to the destruction of osmoreceptors in the hypothalamus. These adipsic CDI patients are easily dehydrated and the consequent dehydration could be life-threatening. The objective of this study was to investigate the prognosis of adipsic CDI patients. We have reviewed 149 patients with CDI in three hospitals using databases of the electronic medical recording systems, and examined whether adipsia could affect the morbidity and mortality in CDI patients with multivariable analyses. Twenty-three patients with CDI were adipsic while the remaining 126 patients were non-adipsic. The multivariate analyses showed that the incidence of serious infections which required hospitalization was significantly higher in the adipsic CDI patients compared to that in non-adipsic CDI patients (p <0.001). A total of 6 patients with CDI died during the follow-up (median duration; 60 months, range 1 to 132 months). Four of them were adipsic, three of whom died of infection. The statistical analyses revealed that the risk of death in adipsic CDI patients was significantly higher than in non-adipsic patients (p =0.007). It is thus suggested that adipsic CDI patients were susceptible to serious infections which could be the causes of death.

[A practical algorithm for polydipsia in children]

There is a lack of consent on a clinical diagnostic work-up for children with polydipsia. This can result in a delay in diagnosis in some children and unnecessary investigations in others. We describe three children who presented with polydipsia. Two of them were diagnosed with psychogenic polydipsia and one with central diabetes insipidus. We discuss the differential diagnosis and relevant clinical signs before going on to propose a clinical diagnostic algorithm that can be used in children with polydipsia. A systematic diagnostic work up for children with polydipsia helps to differentiate between those in whom polydipsia is unlikely to have a somatic cause and those where a water deprivation-test is indicated. A water deprivation test in children is an invasive procedure and should be performed by a paediatric endocrinologist or nephrologist.

Growth retardation due to panhypopituitarism and central diabetes insipidus following Russell's viper bite

Russell's viper envenomation and its related complications, especially acute kidney injury, is an important cause of morbidity and mortality in tropical developing countries of South Asia. Unusual complications, especially hypopituitarism, are rare and probably missed due to lack of clinical suspicion and diagnostic facilities. We report a rare presentation of growth retardation resulting from hypopituitarism due to Russell's viper envenomation along with central diabetes insipidus. Awareness of the fact that hypopituitarism may occur in this clinical setting is necessary for early diagnosis and treatment, especially among general care practitioners taking care of these patients.

[Acute myeloid leukemia with monosomy 7 and inv(3)(q21q26.2) complicated with central diabetes insipidus]

A 20-year-old female presented with thirst, polyposia, and polyuria and was referred to our hospital because of leukocytosis and anemia. Bone marrow aspiration revealed 66.8% myeloperoxidase-positive blasts and trilineage myelodysplasia. The karyotype was 45, XX, inv(3)(q21q26.2), -7[19]. Therefore, a diagnosis of AML with inv(3)(q21q26.2) complicated by -7 was made. Moreover, hyposthenuria and a low anti-diuretic hormone (ADH) level were observed. Although cerebrospinal fluid analysis was normal, magnetic resonance imaging (MRI) revealed the absence of hyperintensity in the neurohypophysis in T1-weighted images. Therefore, she was also diagnosed with diabetes insipidus. After she was administered a desmopressin nasal spray, the volume of urine produced decreased. Following treatment with second induction therapy containing high-dose cytarabine for AML, she achieved complete remission in the bone marrow. Moreover, when the abnormality on MRI and the volume of urine were normalized, she discontinued desmopressin. Although diabetes insipidus is a rare complication of AML, the majority of AML patients who have diabetes insipidus have the abnormal karyotypes with inv(3)(q21q26.2)/t(3;3)(q21;q26.2) and monosomy 7. Further study is required to clarify the pathogenesis and develop a strategy for the treatment of this category of AML.

Suprasellar non-Langerhans cell histiocytosis (Erdheim-Chester disease)--a case report

Erdheim-Chester disease (ECD) is an uncommon non-Langerhans cell histiocytosis that affects multiple body systems and can present clinically in a myriad of ways. An adult onset is most common with bony involvement and constitutional symptoms. We report the case of a 52-year-old female presenting with diabetes insipidus and a suprasellar mass on imaging, with no evidence of extracerebral involvement. Histopathology was consistent with ECD.

[Perioperative management of a child with central diabetes insipidus who underwent two surgeries before and after desmopressin administration]

A 14-year-old girl weighing 32 kg was diagnosed with suprasellar tumor causing hydrocephalus, hypothyroidism, adrenal dysfunction and central diabetes insipidus. She was treated with levothyroxine and hydrocortisone and urged to take fluid to replace urine. She was scheduled to undergo ventricular drainage to relieve hydrocephalus prior to tumor resection. For the first surgery, desmopressin was not started and urine output reached 4,000 to 6,000 ml x day(-1), urine osmolality 64 mOsm x l(-1) and urine specific gravity 1.002. Anesthesia was induced with sevoflurane and maintained with propofol and remifentanil. Maintenance fluid was with acetated Ringer's solution and urine loss was replaced with 5% dextrose. Bradycardia and hypotension occurred after intubation, which was treated with volume load. Infusion volume was 750 ml and urine output was 1100 ml during 133 min of anesthesia. Postoperative day 1 nasal desmopressin was started. Ten days later, partial tumor resection was performed. Anesthesia was induced with propofol and fentanyl and maintained with sevoflurane and remifentanil. Infusion volume was 610 ml, urine output 380 ml, and blood loss 151 ml during 344 min of anesthesia. Hemodynamic parameters were stable throughout the procedure. Pathology of the tumor was revealed to be germinoma. Bradycardia and hypotension experienced during the first surgery was suspected to be caused by preoperative hypovolemia brought by polyuria. Desmopressin was proved to be effective to treat excessive urine output and to maintain good perioperative water balance.

Variant of lymphocytic infundibulo-neurohypophysitis presenting with unique clinical and radiological features

Lymphocytic hypophysitis (LYH) is a chronic inflammation that primarily affects the pituitary gland. This disorder has recently been classified into lymphocytic adenohypophysitis (LAH), lymphocytic infundibulo-neurohypophysitis (LINH), and lymphocytic infundibulo-panhypophysitis (LIPH) according to the affected area. We report a case of LINH in a 68-year-old woman who presented with diabetes insipidus (DI). In this case, the posterior lobe was affected in both endocrinological assessment and magnetic resonance imaging (MRI) findings. In contrast, the anterior pituitary was not affected in endocrinological assessment but was affected in MRI findings. Indeed, the patient did not develop hypopituitarism. We believed that these clinical and radiological features were unique in regard to the classification of LYH. To confirm the classification of LYH and the distinction from pituitary adenoma, a pituitary biopsy was performed. Based on the pathological and endocrinological assessment, the patient's disorder was finally diagnosed as a variant of LINH. Current evidence recommends that surgical intervention for LYH should be avoided because the natural course of LYH is essentially self-limiting. Therefore, the accumulation of the knowledge of many variants of LYH is important for the preoperative differential diagnosis of pituitary masses. Our clinical observation could be useful for avoiding unnecessary surgical intervention.

Profound hypernatremia due to central diabetes insipidus

Diabetes insipidus is a rare endocrine disorder in paediatric patients. Polyuria is a cardinal manifestation that is extremely difficult to recognize in diapered infants. Careful urine quantification is the key to diagnosis in appropriate clinical setting. We report a case of a 4 months old infant presenting with an acute life threatening event following an episode of vomiting and decreased oral intake. She had profound hypernatremia which persisted after stabilization. Polyuria unrecognized by the mother was revealed by 24-hour urine output measurement. A diagnosis of diabetes insipidus was made after appropriate laboratory investigations including serum and urine osmolality. The central nature of the disease was confirmed by neuroimaging which showed holoprosencephaly.

Anterior hypopituitarism is rare and autoimmune disease is common in adults with idiopathic central diabetes insipidus

OBJECTIVE

Central diabetes insipidus is a rare clinical condition with a heterogenous aetiology. Up to 40% of cases are classified as idiopathic, although many of these are thought to have an autoimmune basis. Published data have suggested that anterior hypopituitarism is common in childhood-onset idiopathic diabetes insipidus. We aimed to assess the incidence of anterior hypopituitarism in a cohort of adult patients with idiopathic diabetes insipidus.

DESIGN AND PATIENTS

We performed a retrospective review of the databases of two pituitary investigation units. This identified 39 patients with idiopathic diabetes insipidus. All had undergone magnetic resonance imaging scanning and dynamic pituitary testing (either insulin tolerance testing or GHRH/arginine and short synacthen testing) to assess anterior pituitary function.

RESULTS

One patient had partial growth hormone deficiency; no other anterior pituitary hormonal deficits were found. Thirty-three percent had at least one autoimmune disease in addition to central diabetes insipidus.

CONCLUSIONS

Our data suggest that anterior hypopituitarism is rare in adult idiopathic diabetes insipidus. Routine screening of these patients for anterior hypopituitarism may not, therefore, be indicated. The significant prevalence of autoimmune disease in this cohort supports the hypothesis that idiopathic diabetes insipidus may have an autoimmune aetiology.

Central diabetes insipidus and hypothalamic type of hypopituitarism associated with atypical location of Rathke's cleft cyst

A 68-year-old woman was admitted to determine the pathogenesis of weight loss and polyuria. Physical findings on admission showed BMI of 20.9, blood pressure of 147/69 mmHg, and that she had ciliac, axillar and pubic hair loss. Laboratory findings showed that plasma adrenocorticotropic hormone (ACTH) was 4.6 pg/mL with serum cortisol of 1.2 µg/dL. Serum luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were markedly reduced. Serum growth hormone (GH) and insulin growth factor (IGF)-1 were 0.054 ng/mL and 25 ng/mL, respectively. Serum prolactin was as high as 85.6 ng/mL. The levels of all the pituitary hormones were elevated in response to a mixture of exogenous corticotrophin-releasing hormone (CRH), luteinizing hormone-releasing hormone (LH-RH), thyrotropin-releasing hormone (TRH), and growth hormone-releasing hormone (GRH). However, there was no response of ACTH and GH release to insulin-induced hypoglycemia and no response of LH and FSH release to clomiphene. Urine volume was more than 4,000 mL, with low urine osmolality of 134 mmol/kg. Plasma arginine vasopressin (AVP) was 0.8 pg/mL. There was no increase in urine osmolality and plasma AVP in response to 5% hypertonic saline load. Magnetic resonance imaging revealed Rathke's cleft cyst at the pituitary stalk level, but there was no abnormal finding in the hypothalamus. These findings indicate central diabetes insipidus and hypothalamic type of hypopituitarism, resulting from the atypical location of Rathke's cleft cyst.

Reversible impairment of the processing of proopiomelanocortin into ACTH in pituitary enlargement suspected of lymphocytic hypophysitis

We describe a 64-year-old woman with a cystic pituitary mass presenting with central diabetes insipidus. Brain magnetic resonance imaging (MRI) with enhancement showed enlargement of the pituitary gland with cystic portions and thickening of the pituitary stalk with homogeneous enhancement. Combined anterior pituitary stimulation test and insulin-induced hypoglycemic test confirmed the diagnosis of panhypopituitarism, including adrenocortical insufficiency due to pituitary and hypothalamic dysfunction by stalk compression. Interestingly, the response of serum cortisol to CRH was low and delayed, in contrast to the marked increase in plasma ACTH. Molecular analysis of her plasma ACTH by Sephadex G75 gel exclusion chromatography coupled with radioimmunoassay (RIA) indicated a peak for high molecular weight ACTH, i.e., proACTH, in addition to that for 1-39 ACTH. Three years later, enlargement of the pituitary gland with cystic portions and thickening of the pituitary stalk disappeared completely, followed by the decrease in plasma proACTH level. By the results of endocrinological study and the change of pituitary MRI findings, lymphocytic hypophysitis was suggested. Synthesis of immature ACTH is generally thought to be due to impaired processing of the precursor proopiomelanocortin (POMC) through activation of prohormone convertase (PC)-1 by CRH. It is possible that the immature ACTH in this case was produced by impaired processing of the precursor POMC due to decreased CRH, dysfunction of corticotrophs in the anterior pituitary by compression of the normal pituitary, or antibodies targeting hypothalamic and/or pituitary cells. This report suggested that impaired processing of POMC may unusually play a role in adrenocortical insufficiency exhibited in lymphocytic hypophysitis.

Pituitary and systemic autoimmunity in a case of intrasellar germinoma

Germinomas arising in the sella turcica are difficult to differentiate from autoimmune hypophysitis because of similar clinical and pathological features. This differentiation, nevertheless, is critical for patient care due to different treatments of the two diseases. We report the case of an 11-year-old girl who presented with diabetes insipidus and growth retardation, and was found to have an intra- and supra-sellar mass. Initial examination of the pituitary biopsy showed diffuse lymphocytic infiltration of the adenohypophysis and absent placental alkaline phosphatase expression, leading to a diagnosis of hypophysitis and glucocorticoid treatment. Because of the lack of clinical and radiological response, the pituitary specimen was re-examined, revealing this time the presence of scattered c-kit and Oct4 positive germinoma cells. The revised diagnosis prompted the initiation of radiotherapy, which induced disappearance of the pituitary mass. Immunological studies showed that the patient's serum recognized antigens expressed by the patient's own germinoma cells, as well as pituitary antigens like growth hormone and systemic antigens like the Sjögren syndrome antigen B and alpha-enolase. The study first reports the presence of pituitary and systemic antibodies in a patient with intrasellar germinoma, and reminds us that diffuse lymphocytic infiltration of the pituitary gland and pituitary antibodies does not always indicate a diagnosis of autoimmune hypophysitis.

Objective assessment of thirst recovery in patients with adipsic diabetes insipidus

Adipsic diabetes insipidus (ADI) is characterised by impaired thirst and defective AVP secretion. We have assessed the thirst response to graded osmotic stimulation using a visual analog scale (VAS) in patients with a history of ADI following surgery for a craniopharyngioma. The patients were thought to be regaining their thirst response but we wanted to confirm that this was the case objectively before relaxing their strict fluid balance regimen. Three patients with adipisa in the presence of hypernatremia following surgery for a craniopharyngioma are described. Their median age at surgery was 13 years (range 11-15 years). All patients had previously demonstrated no desire to drink despite a serum osmolality in excess of 300 mOsmol/kg. Fluid balance was maintained postoperatively with a regimen involving a fixed daily fluid intake and DDAVP dose together with daily weights and regular assessment of capillary sodium concentrations. Patients were thought to be regaining thirst sensation and so were assessed by hypertonic saline infusion (HSI) with thirst measured using a VAS. Patients underwent a HSI test 4, 6 and 9 months post surgery. All had abnormally low AVP production at raised plasma osmolalities but the visual analogue scale confirmed partial or complete thirst recovery. The intensive regimen used to maintain stable serum sodium concentrations was relaxed without the patients subsequently developing a significant hyperosmolar state. We have shown objective recovery of thirst perception in patients with adipsia within 9 months of surgery, despite persistence of cranial diabetes insipidus. These observations indicate that both osmoreceptors regulating thirst and their efferent pathways demonstrate more plasticity than those regulating AVP production. The HSI and thirst VAS are an objective way of assessing patients known to have ADI who are thought to be recovering thirst perception.