Desmopressin Dose Requirements in Adults with Congenital and Acquired Central Diabetes Insipidus

Central diabetes insipidus is a rare disorder characterized by a deficiency of vasopressin. The first line drug to treat this disorder is a synthetic analogue of vasopressin, desmopressin.The primary aim of this retrospective register study was to compare desmopressin dose requirements in patients with acquired and congenital DI, and secondly to assess the influence of BMI on dose requirement and risk of hyponatremia with different drug administrations. We included all patients with suspected DI attending the endocrine department at Rigshospitalet, Copenhagen, Denmark in 2022. We identified 222 patients who were included whereof 130/222 (58.6%) were females and median age was 53 years (IQR 35 to 63). The etiology included 7/222 (3.2%) congenital and 215/222 (96.8%) acquired. After converting nasal and sublingual doses to equivalent oral doses, the median daily dose requirement was 600 μg in patients with congenital etiology compared to 200 μg in patients with acquired etiology (p=0.005). We found no association between BMI and desmopressin dose requirements (p=0.6). During the past 12 months, 66/215 (30.7%) had sodium levels<136 mmol/l including 20/215 (9.3%) with sodium levels<131 mmol/l. No increased risk of hyponatremia was found, when nasal and oral were compared (p=0.9). Daily desmopressin dose requirements were higher in patients with congenital DI compared to patients with acquired DI. However, this result was associated with uncertainty due to the small congenital group. BMI did not influence daily dose requirements and nor did type of administration influence the risk of hyponatremia.

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.

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.

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.

Management of Central Diabetes Insipidus in Disabled Children with Diluted Oral Desmopressin Lyophilisate Formulation Administered Through Nasogastric Tube: A Retrospective Case Series

BACKGROUND

Experience with nasogastric administration of oral DDAVP [desamino-D-arginine-8-vasopressin] lyophilisate (ODL) for central diabetes insipidus (CDI) in disabled children with swallowing coordination difficulties is limited.

OBJECTIVE

We aimed to assess the safety and efficacy of nasogastric use of ODL in disabled children with CDI. Time to serum sodium normalisation was compared with that of children with normal intellect and CDI treated with sublingual DDAVP.

METHODS

Clinical, laboratory and neuroimaging characteristics were evaluated for 12 disabled children with CDI treated with ODL through nasogastric tube at Dr Behcet Uz Children's Hospital, Turkey, between 2012 and 2022.

RESULTS

Six boys and six girls with a mean (±SD) age of 43 (± 40) months were evaluated. These children (mean [±SD] weight standard deviation score [SDS] - 1.2 ± 1.7; mean [±SD] height SDS - 1.3 ± 1.4) presented with failure to thrive, irritability, prolonged fever, polyuria and hypernatraemia (mean serum sodium 162 [±3.6] mEq/L). At diagnosis, mean serum and urine osmolality were 321 (± 14) mOsm/kg and 105 (± 7.8) mOsm/kg, respectively. Arginine vasopressin (AVP) levels were undetectable (< 0.5 pmol/L) at diagnosis in all patients. Nasogastric tube administration of DDAVP lyophilisate (120 µg/tablet) dissolved in water (10 mL) was commenced at a dose of 1-5 µg/kg/day in two divided doses together with controlled water intake to avoid hyponatraemia. The frequency and dose of DDAVP were titrated based on urine output and serum sodium concentration. Serum sodium declined at a rate of 0.11 ± 0.03 mEq/L/h and reached normal range in a mean duration of 174 ± 46.5 h. Serum sodium declined faster in children with normal intellect and CDI treated with sublingual DDAVP (1.28 ± 0.39 mEq/L/h; p = 0.0003). Three disabled children needed rehospitalisation because of hypernatraemia due to unintentional DDAVP omission by caregivers. No episode of hyponatraemia was observed. Weight gain and growth were normal during the median (± interquartile range) follow-up duration of 32 ± 67 months.

CONCLUSIONS

Nasogastric administration of oral DDAVP lyophilised formulation was safe and effective in the treatment of CDI in disabled children in this small retrospective series.

New developments and concepts in the diagnosis and management of diabetes insipidus (AVP-deficiency and resistance)

Diabetes insipidus (DI) is a disorder characterised by the excretion of large amounts of hypotonic urine, with a prevalence of 1 per 25,000 population. Central DI (CDI), better now referred to as arginine vasopressin (AVP)-deficiency, is the most common form of DI resulting from deficiency of the hormone AVP from the pituitary. The less common nephrogenic DI (NDI) or AVP-resistance develops secondary to AVP resistance in the kidneys. The majority of causes of DI are acquired, with CDI developing when more than 80% of AVP-secreting neurons are damaged. Inherited/familial CDI causes account for approximately 1% of cases. Although the pathogenesis of NDI is unclear, more than 280 disease-causing mutations affecting the AVP2 protein or AVP V2 receptor, as well as in aquaporin 2 (AQP2), have been described. Although the cAMP/protein kinase A pathway remains the major regulatory pathway of AVP/AQP2 action, in vitro data have also revealed additional cAMP independent pathways of NDI pathogenesis. Diagnosing partial forms of DI, and distinguishing them from primary polydipsia, can be challenging, previously necessitating the use of the water deprivation test. However, measurements of circulating copeptin levels, especially after stimulation, are increasingly replacing the classical tests in clinical practice because of their ease of use and high sensitivity and specificity. The treatment of CDI relies on desmopressin administration, whereas NDI requires the management of any underlying diseases, removal of offending drugs and, in some cases, administration of diuretics. A better understanding of the pathophysiology of DI has led to novel evolving therapeutic agents that are under clinical trial.

Infection with SARS-CoV-2 may alter the half-life of desmopressin (DDAVP) in patients with central diabetes insipidus

We present a 9-year-old boy with diabetes insipidus. The boy is treated with desmopressin (DDAVP) therapy. Under this therapy, the drinking quantity and the laboratory parameters were normal. No nocturia occurred any more. In the context of a clinically mild infection with SARS-CoV-2, the duration of action of DDAVP was significantly prolonged (approximately +50%). The original dosage was then reintroduced and was still sufficient until months later. A possible connection to the infection with SARS-CoV-2 can be suspected. Our case report should make physicians who care for patients with diabetes insipidus aware of such a possible prolongation of the effect of DDAVP. More frequent monitoring may be needed in such patients to assess the risk of symptomatic dilutional hyponatremia.

Idiopathic central diabetes insipidus in a large cohort of patients: the hypopituitarism ENEA rare observational (HEROS) study

Central Diabetes Insipidus (CDI) is mainly associated with structural pathologies of the hypothalamic-pituitary area. Etiologies underlying CDI are identified in most patients, however idiopathic CDI is reported in 13-17% of cases after excluding other etiologies. The Hypopituitarism ENEA Rare Observational Study (HEROS study) retrospectively collected data of patients with idiopathic CDI from 14 pituitary centers in 9 countries. The cohort included 92 patients (59 females 64%), mean age at diagnosis was 35.4 ± 20.7 years, and a mean follow up of 19.1 ± 13.5 years following CDI diagnosis. In 6 women, diagnosis was related to pregnancy. Of 83 patients with available data on pituitary imaging, 40(48%) had normal sellar imaging, and 43(52%) had pathology of the posterior pituitary or the stalk, including loss of the bright spot, posterior pituitary atrophy or stalk enlargement. Anterior pituitary hormone deficiencies at presentation included hypogonadism in 6 (6.5%) patients (5 females), and hypocortisolism in one; during follow-up new anterior pituitary deficiencies developed in 6 patients. Replacement treatment with desmopressin was given to all patients except one, usually with an oral preparation. During follow up, no underlying disease causing CDI was identified in any patient. Patients with idiopathic CDI following investigation at baseline are stable with no specific etiology depicted during long-term follow-up.

Second-line regimen for CNS-involved pediatric Langerhans cell histiocytosis

PURPOSE

Langerhans cell histiocytosis (LCH) can affect any organ. Central nervous system (CNS) involvement is rare, and its management is poorly understood. This study aimed to analyze the clinical response and prognosis of pediatric LCH with central diabetes insipidus (CDI) treated with second-line therapy with cytarabine (Ara-c), cladribine (2-cdA), dexamethasone, and vindesine.

METHODS

This retrospective case series study included pediatric LCH with CDI treated at Beijing Children's Hospital affiliated with Capital Medical University (11/2012-01/2018). After the first-line 2009-LCH regimen, patients with active disease/worse response, relapse, or no significant improvement in risk organs, pituitary, or lung were given the second-line therapy. Baseline characteristics, clinical response and adverse reactions were observed.

RESULTS

Twenty-six children with CDI and disappearance of hyperintensity in the posterior pituitary were included. They received "Regimen A" Ara-c + dexamethasone + vindesine (n = 7) or "Regimen B" Ara-c + dexamethasone + vindesine + 2-cdA (n = 19) as second-line therapy. There were 14 patients with CDI but without pituitary stalk thickening (PST) and 12 with CDI and PST. In patients with CDI alone, 4/4 patients receiving Regimen A and 3/10 receiving Regimen B improved. All patients with CDI and PST showed improvement for PST. The reappearance of hyperintensity at the posterior pituitary was observed in 10 patients with CDI. All 26 children were alive after a median follow-up of 40.5 months. There were no chemotherapy-related deaths.

CONCLUSION

A combined therapy with Ara-c, 2-cdA, dexamethasone, and vindesine could partially alleviate pituitary disease conditions in pediatric LCH with CNS involvement, with good tolerance.

Permanent central diabetes insipidus after traumatic brain injury. Case report and literature review

The authors report permanent central diabetes insipidus (CDI) in a patient after severe traumatic brain injury (TBI) in traffic accident. A 16-year-old boy entered to a medical facility in coma (GCS score 6) with the following diagnosis: acute TBI, severe cerebral contusion, subarachnoid hemorrhage, depressed comminuted cranial vault fracture, basilar skull fracture, visceral contusion. CDI was diagnosed in 3 days after injury considering polyuria and hypernatremia (155 mmol/l). Desmopressin therapy was initiated through a feeding tube. Thirst appeared when a patient came out of the coma after 21 days despite ongoing desmopressin therapy. Considering persistent thirst and polyuria, we continued desmopressin therapy in a spray form. Under this therapy, polyuria reduced to 3-3.5 liters per a day. Symptoms of CDI persisted in long-term period (2 years after TBI) while function of adenohypophysis was intact. This case demonstrates a rare development of permanent diabetes insipidus after TBI. CDI manifested only as polyuria and hypernatremia in coma. Thirst joined after recovery of consciousness. Probable causes of CDI were damage to neurohypophysis and partially injury of pituitary stalk because of extended basilar skull fracture and/or irreversible secondary lesion of hypothalamus following diffuse axonal damage after TBI.

Gefitinib Treatment Was Unsuccessful for Central Diabetes Insipidus Due to Pituitary Metastasis of Lung Adenocarcinoma

We herein report a rare case of advanced lung adenocarcinoma with central diabetes insipidus due to pituitary metastasis. Although treatment with gefitinib was dramatically effective, the symptoms of diabetes insipidus did not improve. Radiotherapy for pituitary metastasis was effective to control diabetes insipidus; however, we could not cease the administration of 1-deamino-8-D-arginine vasopressin (DDAVP). It is important for physicians to positively consider radiotherapy for pituitary metastases even if favorable tumor control is achieved with chemotherapy when diabetes insipidus becomes clinically overt. Furthermore, continuous DDAVP administration may be needed to treat central diabetes insipidus.

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.

Neuroendocrine Dysfunction in the Acute Setting of Penetrating Brain Injury: A Systematic Review

BACKGROUND

Data on neuroendocrine dysfunction (NED) in the acute setting of penetrating brain injury (PBI) are scarce, and the clinical approach to diagnosis and treatment remains extrapolated from the literature on blunt head trauma.

METHODS

Three databases were searched (PubMed, Scopus, and Cochrane). Risk of bias was computed using the Newcastle-Ottawa Scale, or the methodological quality of case series and case reports, as indicated. This systematic review was registered in PROSPERO (42020172163).

RESULTS

Six relevant studies involving 58 patients with PBI were included. Two studies were prospective cohort analyses, whereas 4 were case reports. The onset of NED was acute in all studies, by the first postinjury day. Risk factors for NED included worse injury severity and the presence of cerebral edema on imaging. Dysfunction of the anterior hypophysis involved the hypothalamic-pituitary-thyroid axis, treated with hormonal replacement, and hypocortisolism, treated with hydrocortisone. The prevalence of central diabetes insipidus was up to 41%. Most patients showed persistent NED months after injury. In separate reports, diabetes insipidus and hypocortisolism showed an association with higher mortality. The available literature for this review is poor, and the studies included had overall low quality with high risk of bias.

CONCLUSIONS

NED seems to be prevalent in the acute phase of PBI, equally involving both anterior and posterior hypophysis. Despite a potential association between NED and mortality, data on the optimal management of NED are limited. This situation defines the need for prospective studies to better characterize the clinical features and optimal therapeutic interventions for NED in PBI.

Central Diabetes Insipidus in a Preterm Neonate Unresponsive to Intranasal Desmopressin

Central or neurogenic diabetes insipidus (DI) is uncommon in the pediatric age group and rarely occurs in neonates. It should be suspected in any neonate presenting with excessive urine output and hypernatremia that persists despite increased fluid administration. Diabetes insipidus may be secondary to asphyxia, intraventricular hemorrhage, infection, and structural abnormalities or may be idiopathic or genetic. Diagnosis includes a careful history, laboratory testing, and magnetic resonance imaging. Management of neonatal DI involves a careful balance between fluid intake and pharmacologic treatment. In this article we report a case of an extremely low birth weight infant presenting with central DI possibly caused by abnormality of the pituitary gland. Persistent hypernatremia was the initial presentation. Increased fluids were given initially but were only partially helpful. Eventually subcutaneous desmopressin (DDAVP) was required. The infant was unresponsive to intranasal DDAVP and required subcutaneous DDAVP upon discharge.

Central diabetes insipidus unveiled by glucocorticoid therapy in a patient with an empty sella: A case report and literature review

RATIONALE

Some diseases contribute to hypopituitarism without clinical manifestations and the glucocorticoid therapy may unveil central diabetes insipidus. The condition is rare and usually causes problems for clinical physicians.

PATIENT CONCERNS

A 59-year-old woman presented to our hospital due to facial numbness and persistent eyelid heaviness.

DIAGNOSIS

Physical examination and cerebrospinal fluid examination supported a diagnosis of Guillain-Barre[Combining Acute Accent] syndrome. Magnetic resonance imaging showed an empty sella. Hormone test indicated hypopituitarism.

INTERVENTIONS

The patient received intravenous immunoglobulin and glucocorticoid. Central diabetes insipidus appeared after 20 days. Subsequently, the patient was prescribed 1-desamino-8-D-arginine vasopressin and prednisone.

OUTCOMES

During 6 months' follow-up, the patient's urine output was gradually reduced to normal level.

LESSONS

This case indicated that hypopituitarism may be caused by an empty sella and be masked by adrenal insufficiency. Central diabetes insipidus may present after glucocorticoid therapy.

Management of central diabetes insipidus

The treatment of central diabetes insipidus has not changed significantly in recent decades, and dDAVP and replacement of free water deficit remain the cornerstones of treatment. Oral dDAVP has replaced nasal dDAVP as a more reliable mode of treatment for chronic central diabetes insipidus. Hyponatraemia is a common side effect, occurring in one in four patients, and should be avoided by allowing a regular break from dDAVP to allow a resultant aquaresis. Hypernatraemia is less common, and typically occurs during hospitalization, when access to water is restricted, and in cases of adipsic DI. Management of adipsic DI can be challenging, and requires initial inpatient assessment to establish dose of dDAVP, daily fluid prescription, and eunatraemic weight which can guide day-to-day fluid targets in the long-term.

Role of 18F-fluorodeoxyglucose (FDG) and 18F-2-fluorodeoxy sorbitol (FDS) in autoimmune hypophysitis: a case report

BACKGROUND

Autoimmune hypophysitis is a rare disease characterized by the infiltration of lymphocytic cells into the pituitary gland. ¹⁸F-fluorodeoxyglucose (FDG) and ¹⁸F-2-fluorodeoxy sorbitol (FDS) positron emission tomography (PET) are well-established and emerging techniques, respectively, which may aid in the diagnosis and classification of autoimmune hypophysitis.

CASE PRESENTATION

Here, we report a 40-year-old female diagnosed with central diabetes insipidus and multiple pituitary hormone deficiencies, and MRI revealed homogeneous signals in the pituitary gland as well as thickened in the pituitary stalk. FDG PET localized the pituitary and pituitary stalk lesions and displayed an SUVmax of 5.5. FDS, a sensitive radiotracer for bacterial infections but remains unproven under aseptic inflammation, also demonstrated elevated radioactivity, with an SUVmax of 1.1 at 30 min and 0.73 at 120 min. Transnasal biopsy suggested a diagnosis of autoimmune hypophysitis, and the patient displayed radiological and clinical improvement after treatment with glucocorticoids and hormone replacement.

CONCLUSIONS

Autoimmune hypophysitis can display elevated FDG uptake, which aids in the localization of the lesions. In addition to revealing bacterial infection specifically, FDS can also accumulate under autoimmune conditions, suggesting that it could serve as a potential radiotracer for both bacterial and aseptic inflammation.

TRIAL REGISTRATION

The patient was enrolled in study NCT02450942 (clinicaltrials.gov, Registered May 21, 2015).

[Refractory Erdheim-Chester disease with central nervous system lesion complicated by central diabetes insipidus]

We report a case of Erdheim-Chester disease (ECD) complicated with central diabetes insipidus that was refractory to several treatments. A 58-year-old female suffered from fatigue, fever, thirst, polyuria, leg pain, xanthoma of her upper eyelids, and disturbance of consciousness. Computed tomography (CT) imaging showed infiltration of perivascular soft tissue surrounding the aorta, hydronephrosis, and sclerotic lesions of the femurs and tibias. Magnetic resonance imaging showed the enhancement of expansile pachymeningeal lesions. A water deprivation test revealed the presence of central diabetes insipidus. The results of skin and bone marrow biopsies were consistent with ECD. The patient was treated with prednisone (30 mg daily) and interferon-α (6 mIU three times/week). The perivascular soft tissue showed a slight improvement, but she experienced cerebral hemorrhage 4 and 8 months later. Subsequently, she was treated biweekly with IV tocilizumab (8 mg/kg). Although her clinical symptoms improved, enlargement of the meningeal tumor and hydrocephalus led to disturbance of consciousness 6 months later. After the surgical debulking of the intracranial lesion, she was treated with two cycles of IV cladribine (0.12 mg/kg for 5 d). She had a transient clinical improvement but developed central nervous system disease marked by progressive neurological symptoms.

Isolated Langerhans cell histiocytosis in the hypothalamic-pituitary region: a case report

BACKGROUND

Langerhans cell histiocytosis (LCH) is a rare disease that mainly affects children, but this disease is significantly rarer in patients who are older than 15 years. In this disease, any organ can be involved. The skeleton, skin and lung are commonly affected, and isolated hypothalamic-pituitary (HP) involvement is relatively rare. Here we report a 17-year-old adolescent with isolated HP-LCH of enlarged pituitary stalk presented with central diabetes insipidus (CDI).

CASE PRESENTATION

A 17-year-old male adolescent with polydipsia and polyuria accompanied with elevated serum sodium level and low urine osmolality for 3 weeks was referred to our hospital. After admission, hormonal evaluation showed that his growth hormone (GH) was slightly elevated, and serum osmolality and glucose were normal. The fluid deprivation-vasopressin test demonstrated CDI. Imaging examination showed an obvious thickening of the pituitary stalk. Lymphocytic hypophysitis, sarcoidosis and granulation tissue lesions were suspected. After oral 1-deamino-8-Darginine vasopressin (DDAVP) and prednisone were administered for 2 months, symptoms were relieved, and he discontinued taking the drugs by himself. On reexamination, imaging revealed changes in the size and shape of the pituitary stalk, with thickened nodules. Then, a diagnostic biopsy of the pituitary stalk lesion was performed. Immunohistochemistry confirmed the definitive diagnosis of LCH. The clinical symptoms subsided with oral hormone replacements.

CONCLUSION

CDI is a rare symptom in children and adolescents. Most of the causes are idiopathic, while others are caused by central nervous system (CNS) disorders. Meanwhile, lymphocytic hypophysitis, germinoma, LCH and other CNS disorders can all present as thickening of the pituitary stalk, diffuse enlargement of the pituitary gland, and weakening of high signal intensity in the neurohypophysis on magnetic resonance imaging (MRI). The differential diagnosis among these diseases depends on immunohistochemistry evidence.

Central diabetes insipidus: beware of Langerhans cell histiocytosis!

Langerhans cell histiocytosis (LCH) is a rare disorder, characterised by a monoclonal proliferation of aberrant histiocytes that accumulate in and infiltrate into different organs. When the hypothalamic-pituitary axis is involved, central diabetes insipidus (CDI) can be its first manifestation. Three cases of LCH with central diabetes insipidus were retrospectively analyzed: Case 1 is a 41-year old female presenting with polyuria and polydipsia. Diabetes insipidus was diagnosed and treated with desmopressin. MRI pituitary showed hypophysitis. Subsequently, she developed bone lesions and a biopsy demonstrated LCH. Case 2 is a 51-year old female presenting in 2009 with polyuria and polydipsia. Diabetes insipidus was diagnosed and treated with desmopressin. MRI pituitary revealed hypophysitis. LCH was suspected because of known pulmonary histiocytosis. Coexisting bone lesions were biopsied and confirmed LCH. Case 3 is a 44-year old female presenting with diabetes insipidus. She was treated with desmopressin as well. MRI of the pituitary gland showed impressive thickening of the infundibulum. A few months later, she developed skin lesions and a biopsy revealed LCH. Conclusively, LCH is a rare, elusive and probably underdiagnosed disease with a broad disease spectrum. Due to infiltration of the hypothalamic-pituitary axis, CDI can be the first manifestation, even before LCH is diagnosed. Therefore, LCH should be considered in the diagnostic workup of CDI.

Anti-PD-L1 Treatment Induced Central Diabetes Insipidus

CONTEXT

Immune checkpoint inhibitors, including anti-programmed cell death protein 1 (PD-1), anti-programmed cell death protein ligand 1 (PD-L1), and anti-cytotoxic T-lymphocyte antigen 4 (anti-CTLA4) monoclonal antibodies, have been widely used in cancer treatment. They are known to cause immune-related adverse events (irAEs), which resemble autoimmune diseases. Anterior pituitary hypophysitis with secondary hypopituitarism is a frequently reported irAE, especially in patients receiving anti-CTLA4 treatment. In contrast, posterior pituitary involvement, such as central diabetes insipidus (DI), is relatively rare and is unreported in patients undergoing PD-1/PD-L1 blockade.

CASE DESCRIPTION

We describe a case of a 73-year-old man with Merkel cell carcinoma who received the anti-PD-L1 monoclonal antibody avelumab and achieved partial response. The patient developed nocturia, polydipsia, and polyuria 3 months after starting avelumab. Further laboratory testing revealed central DI. Avelumab was held and he received desmopressin for the management of central DI. Within 6 weeks after discontinuation of avelumab, the patient's symptoms resolved and he was eventually taken off desmopressin. The patient remained off avelumab and there were no signs or symptoms of DI 2 months after the discontinuation of desmopressin.

CONCLUSION

To our knowledge, this is the first report of central DI associated with anti-PD-L1 immunotherapy. The patient's endocrinopathy was successfully managed by holding treatment with the immune checkpoint inhibitor. This case highlights the importance of early screening and appropriate management of hormonal irAEs in subjects undergoing treatment with immune checkpoint inhibitors to minimize morbidity and mortality.

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.

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.

Buccally Administered Intranasal Desmopressin Acetate for the Treatment of Neurogenic Diabetes Insipidus in Infancy

CONTEXT

The treatment of neurogenic diabetes insipidus (DI) in infancy is challenging and complicated by fluid overload and dehydration. Therapy with subcutaneous (SC), intranasal (IN), or oral tablet desmopressin acetate (1-desamino-8-D-arginine vasopressin [DDAVP]) remains difficult to titrate in infants.

OBJECTIVE

Assess the efficacy and safety of buccally administered IN DDAVP for the management of infants with neurogenic DI.

DESIGN, SETTING, PARTICIPANTS, AND INTERVENTION

Retrospective review of clinical and laboratory data of 15 infants (mean age, 4.5 mo) with neurogenic DI treated at a tertiary care center. Treatment was with diluted IN DDAVP formulation (10 mcg/mL) administered buccally via a tuberculin syringe to the buccal mucosa.

RESULTS

After initial DDAVP titration of 2-3 days, IN DDAVP doses ranged from 1 to 5 mcg twice daily given buccally. Mean serum sodium concentration at DI diagnosis was 159 ± 6.6 mmol/L (range, 151-178) and improved to 142 ± 3.5 mmol/L (range, 137-147) with the buccally administered IN DDAVP. Normal sodium concentrations were established without major fluctuations. Serum sodium was then maintained in the outpatient setting at a mean of 145.7 ± 4.8 mmol/L (mean duration of follow-up, 11 mo).

CONCLUSIONS

Buccally administered IN formulation of DDAVP provides a practical and safe treatment alternative for neurogenic DI in infancy. Our approach avoided severe hypo- and hypernatremia during DDAVP titration and ongoing outpatient management of DI. The possibility for smaller dosage increments and ease of administration make IN DDAVP administered buccally preferable over other DDAVP treatment options in infants.

Transient Intraoperative Central Diabetes Insipidus in Moyamoya Patients Undergoing Revascularization Surgery: A Mere Coincidence?

We present 2 patients with Moyamoya disease undergoing revascularization surgery who developed transient intraoperative central diabetes insipidus with spontaneous resolution in the immediate postoperative period. We speculate that patients with Moyamoya disease may be predisposed to a transient acute-on-chronic insult to the arginine vasopressin-producing portion of their hypothalamus mediated by anesthetic agents. We describe our management, discuss pertinent literature, and offer possible mechanisms of this transient insult. We hope to improve patient safety by raising awareness of this potentially catastrophic complication.

Autoimmune lymphocytic hypophysitis in association with autoimmune eye disease and sequential treatment with infliximab and rituximab

INTRODUCTION

Autoimmune lymphocytic hypophysitis associates predominantly with other autoimmune endocrinopathies and is most commonly treated with glucocorticoids and/or decompressive pituitary surgery. Here we report a new association and treatment modality for lymphocytic hypophysitis.

METHODS

A 52-year-old woman presented with scleritis, uveitis, facial palsy, and central diabetes insipidus, accompanied by thickened pituitary stalk and enlarged pituitary on cranial MRI. Neurosarcoidosis was suspected and treatment with glucocorticoids and methotrexate initiated. Since symptoms persisted, infliximab (a monoclonal antibody that antagonizes tumor necrosis factor alpha) was added to her regimen. The patient initially improved but after 6 months developed recurrent pituitary enlargement, bilateral optic neuritis, and panhypopituitarism. To ascertain the nature of the pituitary lesion, she underwent transsphenoidal biopsy, which revealed lymphocytic hypophysitis with numerous CD20 positive B lymphocytes. The pathological finding suggested to us that administration of rituximab (a monoclonal antibody that lyzes B cells expressing CD20) could be useful. Following two courses of rituximab, the pituitary mass resolved and the corticotroph axis partially recovered. The patient has remained in remission during 3 years of follow up.

CONCLUSION

This is the first report of hypophysitis occurring with the triad of scleritis, uveitis, and optic neuritis, as well as the first immunotherapy based on the sequential use of infliximab and rituximab.

Management of diabetes insipidus and adipsia in the child

Central diabetes insipidus (CDI) is a complex and heterogeneous clinical syndrome affecting the hypothalamic-neurohypophyseal network and water balance. A recent national surveillance in Denmark showed a prevalence rate of twenty-three CDI patients per 100,000 inhabitants in five years. The differential diagnosis between several presenting conditions with polyuria and polydipsia is puzzling, and the etiological diagnosis of CDI remains a challenge before the identification of an underlying cause. For clinical practice, a timely diagnosis for initiating specific treatment in order to avoid central nervous system damage, additional pituitary defects and the risk of dissemination of germ cell tumor is advisable. Proper etiological diagnosis can be achieved via a series of steps that start with careful clinical observation of several signs and endocrine symptoms and then progress to more sophisticated imaging tools. This review summarizes the best practice and approach for the diagnosis and treatment of patients with CDI.

Pregnancy may favour the development of severe autoimmune central diabetes insipidus in women with vasopressin cell antibodies: description of two cases

Recently, an increased incidence of central diabetes insipidus (CDI) in pregnancy, and less frequently in the post partum period, has been reported, most probably favoured by some conditions occurring in pregnancy. This study was aimed at investigating the influence of pregnancy on a pre-existing potential/subclinical hypothalamic autoimmunity. We studied the longitudinal behaviour of arginine-vasopressin cell antibodies (AVPcAbs) and post-pituitary function in two young women with a positive history of autoimmune disease and presence of AVPcAbs, but without clinical CDI, and who became pregnant 5 and 7 months after our first observation. The behaviour of post-pituitary function and AVPcAbs (by immunofluorescence) was evaluated at baseline, during pregnancy and for 2 years after delivery. AVPcAbs, present at low/middle titres at baseline in both patients, showed a titre increase during pregnancy in one patient and after delivery in the other patient, with development of clinically overt CDI. Therapy with 1-deamino-8-d-arginine vasopressin (DDAVP) caused a prompt clinical remission. After a first unsuccessful attempt of withdrawal, the therapy was definitively stopped at the 6th and the 7th month of post partum period respectively, when AVPcAbs disappeared, accompanied by post-pituitary function recovery, persisting until the end of the follow-up. The determination of AVPcAbs is advisable in patients with autoimmune diseases planning their pregnancy, because they could be considered good predictive markers of gestational or post partum autoimmune CDI. The monitoring of AVPcAb titres and post-pituitary function during pregnancy in these patients may allow for an early diagnosis and an early replacement therapy, which could induce the disappearance of these antibodies with consequent complete remission of CDI.

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.

Comparison of incidence of hyponatremia between intranasal and oral desmopressin in patients with central diabetes insipidus

Central diabetes insipidus (CDI), which is characterized by polyuria and polydipsia, is caused by a deficiency of the antidiuretic hormone arginine vasopressin (AVP). While CDI is treated with desmopressin, an analogue of AVP, the intranasal formulation is inconvenient and CDI patients reportedly prefer the oral formulation to the intranasal one. In Japan, intranasal desmopressin had been the only formulation for the treatment of CDI until 2012, when the desmopressin orally disintegrating tablet (ODT) was approved for treatment. In this study we analyzed 26 patients with CDI in whom intranasal desmopressin was switched to desmopressin ODT. The mean daily dose of intranasal desmopressin was 10 ± 8 μg/day, and that of desmopressin ODT was 142 ± 59 μg/day. The mean serum sodium levels were 140 ± 5 mmol/L and 140 ± 3 mmol/L with intranasal desmopressin and desmopressin ODT, respectively, and there were no significant differences between these values. The frequency of hyponatremia (<135 mmol/L) with intranasal desmopressin was 11.7% and that with desmopressin ODT was 7.6%, while the frequency of hyponatremia (<130 mmol/L) with intranasal desmopressin was 4.2% and that with desmopressin ODT was 1.3%. Statistical analyses revealed that incidence of hyponatremia was significantly decreased after the switch to desmopressin ODT. Thus, it is suggested that water balance is better controlled with desmopressin ODT than with intranasal desmopressin in patients with CDI.

Idiopathic central diabetes insipidus presenting in a very low birth weight infant successfully managed with lyophilized sublingual desmopressin

Neonatal central diabetes insipidus (DI) is an extremely rare disorder that can cause severe morbidity and mortality. We have reported a very low birth weight infant with idiopathic central DI presenting in the first month of life who was successfully treated with sublingual desmopressin therapy. In this report, we emphasize that central DI should be kept in mind in an infant with unexplained hypernatremia and polyuria. Timely diagnosis and treatment with lyophilized desmopressin may prevent severe morbidity and mortality.

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.

National Surveillance of Central Diabetes Insipidus (CDI) in Denmark: results from 5 years registration of 9309 prescriptions of desmopressin to 1285 CDI patients

CONTEXT

Epidemiological data for central diabetes insipidus (CDI) are sparse.

OBJECTIVE

The purpose of this study was to provide accurate epidemiological data on CDI on a national level.

DESIGN AND SETTING

This was a drug utilization and patient registry study during a 5-year period from 2007 to 2011.

METHODS

We used the Danish National Prescription Registry data linked with the Danish National Patient Registry to study the epidemiology of CDI using waiting time distribution and other pharmacoepidemiological methods.

PATIENTS

A total of 1285 patients with CDI were recorded in the observation period and given 9309 prescriptions for desmopressin in the nasal formulation, orodispersible tablet, or conventional tablet.

RESULTS

The period prevalence rate of CDI in Denmark over the 5-year period investigated was 23 CDI patients per 100 000 inhabitants, with a higher prevalence in children and older adults (>80 years of age). The 1-year period prevalence rate of CDI decreased in Denmark over the 5 years from approximately 10 to 7 CDI patients per 100 000 inhabitants. The yearly incidence rate of new cases of CDI was found to be 3 to 4 patients per 100 000. The incidence of (presumable) congenital CDI was found to be 2 infants per 100 000 infants. Half of the patients with CDI prescribed as oral treatment were provided dosing instructions to only administer the drug before bedtime, and one third of the CDI patients either had no specific instructions or were instructed to use the drug as needed. Hospital admissions due to severe hyponatremia occurred in 0.9% of patients over a 5-year period, predominantly in females with an incidence ratio of women to men of 1.8:1.

CONCLUSION

Half of the cases of CDI are acquired later in life. At least half of the patients with CDI are instructed to prevent nocturnal polyuria, but it is not clear whether their CDI remains uncontrolled during the daytime or, alternatively, whether they use desmopressin only as needed. Female patients with CDI had approximately twice the number of hospital admissions due to severe hyponatremia than male patients with CDI.

Desmopressin orally disintegrating tablet in Japanese patients with central diabetes insipidus: a retrospective study of switching from intranasal desmopressin

Central diabetes insipidus (CDI) is a rare disease characterized by polyuria and polydipsia. Patients with CDI have been successfully treated with desmopressin administered either by intranasal instillation or oral tablets. Recently, a desmopressin orally disintegrating tablet (ODT) was approved as the first oral desmopressin tablet for CDI treatment in Japan. We conducted a retrospective single-center study of 15 Japanese CDI patients treated with desmopressin ODT therapy, which aimed to evaluate the efficacy and safety of switching to desmopressin ODT and to analyze the clinical factors that affect the desmopressin ODT dose in Japanese patients. The daily mean dose of desmopressin ODT was 104 ± 46.30 μg and the mean ratio of oral to nasal desmopressin dose was 17.0 ± 7.6, both of which are considerably smaller than those of previous dose-titration study. Moreover, the nasal spray group needed significantly smaller ratios of nasal to oral desmopressin than the nasal drop group (11.7 ± 6.5 vs 21.0 ± 5.5, p = 0.02). The ratio of oral to nasal desmopressin dose had a significant inverse correlation with the required nasal desmopressin dose. Multiple regression analysis demonstrated the ratios of nasal to oral desmopressin dose depended on intranasal formulations. In conclusion, desmopressin ODT was safe and effective in the treatment of Japanese adult CDI patients. When switching to ODT, we should care about the possibility that patients require smaller ODT doses than what was initially expected based on previously published data and also nasal formulations in terms of their differences of expected switching ratio.

Clinical review: Treatment of neurohypophyseal diabetes insipidus

CONTEXT

In recent years, there have been several improvements in the treatment of neurohypophyseal diabetes insipidus (DI). They include new formulations of the vasopressin analog, desmopressin; a better understanding of the effect of fluid intake on dosing; and more information about treatments of infants, children, and pregnant women who present special challenges. This review aims to summarize past and current information relative to the safety and efficacy of treatments for the types of DI caused by a primary deficiency of vasopressin.

EVIDENCE ACQUISITION

The review is based on publications identified primarily by a PubMed search of the international literature without limitations of date.

EVIDENCE SYNTHESIS

In acute settings where fluid intake is determined by factors other than thirst, desmopressin should be given iv in doses that have a short duration of action and can be adjusted quickly in accordance with changes in hydration as indicated by plasma sodium. In ambulatory patients, the oral formulations (tablet or melt) are preferred for their convenience. If fluid intake is regulated normally by the thirst mechanism, the tablets or melt can be taken safely 1 to 3 times a day in doses sufficient to completely eliminate the polyuria. However, if fluid intake consistently exceeds replacement needs as evidenced by the development of hyponatremia, the dose should be reduced to allow higher than normal rates of urine output or intermittent breakthrough diuresis. This regimen is often indicated in infants or children because their rate of fluid intake tends to be greater than in adults. In all cases, the appropriate dose should be determined by titration, owing to considerable interindividual differences in bioavailability and antidiuretic effect.

CONCLUSIONS

Desmopressin can provide effective and safe therapy for all patients with neurohypophyseal or gestational DI if given in doses and by a route that takes into account the determinants of fluid intake.

Severe water intoxication secondary to the concomitant intake of non-steroidal anti-inflammatory drugs and desmopressin: a case report and review of the literature

Most of the clinical data on the safety profile of desmopressin (DDAVP), which is an effective treatment for both polyuric conditions and bleeding disorders, originate from studies on the tailoring of drug treatment, whereas few reports exist describing severe side effects secondary to drug-drug interaction. We herein describe a case of severe hyponatremia complicated by seizure and coma due to the intake of non-steroidal anti-inflammatory drugs (NSAIDs) in a patient on DDAVP replacement therapy for central diabetes insipidus (DI). A 50-yr-old Caucasian man, with congenital central DI, developed an episode of generalized tonic-clonic seizure, resulting in coma immediately after being admitted to the Emergency Unit for weakness and emesis. Based on his medical history and clinical findings, water intoxication secondary to ketoprofen intake (200 mg/day for the last 3 days) concomitant with DDAVP replacement therapy (Minirin(®) 60 mcg 4 tablets a day) was hypothesized as being the cause of the severe euvolemic hypotonic hyponatremia (natremia 113 mEq/l, plasma osmolality 238 mOsm/Kg). After standard emergency procedures, appropriate gradual restoration of serum sodium levels to the normal range was achieved in 72 hours. Hydratation was maintained according to water excretion and desmopressin therapy was re-introduced. We discuss this case report in the context of the published literature. The present report first highlights the potentially life-threatening side effects associated with over-the-counter NSAIDs during DDAVP replacement therapy for central DI. Risks and benefits of co-treatment should be carefully considered and therapeutic alternatives to NSAIDs should be recommended to patients with central DI in order to improve DDAVP safety.

Efficacy and safety of desmopressin orally disintegrating tablet in patients with central diabetes insipidus: results of a multicenter open-label dose-titration study

Central diabetes insipidus (CDI) is associated with arginine vasopressin (AVP) deficiency with resultant polyuria and polydipsia. Intranasal desmopressin provides physiological replacement but oral formulations are preferred for their ease of administration. This study aimed to demonstrate the efficacy and safety of desmopressin orally disintegrating tablet (ODT) in the treatment of Japanese patients with CDI, and confirm that antidiuresis is maintained on switching from intranasal desmopressin to desmopressin ODT. A total of 20 patients aged 6-75 years with CDI were included in this 4-week multicenter, open-label study. Following observation, patients switched from intranasal desmopressin to desmopressin ODT with titration to optimal dose over ≤5 days at the study site. Following three consecutive doses with stable patient fluid balance, patients were discharged with visits at Weeks 2 and 4. Following titration from intranasal desmopressin to ODT, the mean 24-hour urine volume was unchanged, indicating similar antidiuresis with both formulations. The proportion of patients with endpoint measurements (urine osmolality, 24-hour urine volume, hourly diuresis rate and urine-specific gravity) within normal range at Days 1-2 (intranasal desmopressin) and Week 4 (desmopressin ODT) was similar. The mean daily dose ratio of intranasal desmopressin to desmopressin ODT (Week 4) was 1:24 but a wide range was observed across individuals to maintain adequate antidiuretic effect. Hyponatraemia was generally mild and managed by dose titration. Desmopressin ODT achieved sufficient antidiuretic control compared to intranasal therapy and was well tolerated over long-term treatment. The wide range of intranasal:ODT dose ratios underline the importance of individual titration.

[Central diabetes insipidus: diagnosis and management]

Central diabetes insipidus (CDI) is caused by deficient secretion of antidiuretic hormone (ADH) due to different conditions that can affect the hypothalamic neurons. It results in an inability to retain normal quantities of free water, which leads to polyuria, including at night, and polydipsia. In adults, it is mostly due to the "idiopathic" form or present after pituitary surgery or a traumatic brain injury. In rare cases, an underlying systemic disease is found. The diagnosis of CDI is based on the water deprivation test. Pituitary MRI and specific clinical and biological work-up are recommended to precise etiology. Treatment of choice is desmopressin, a synthetic analogue of the endogenous ADH hormone. A multidisciplinary team generally provides management and monitoring of CDI.

The hypothalamic-neurohypophyseal system: current and future treatment of vasopressin and oxytocyn related disorders

The hypothalamus and posterior pituitary form a complex neurohumoral system playing a key role in maintaining body fluid homeostasis and reproductive function. We review the pathophysiology mechanisms of posterior pituitary hormones and their implications, beyond water balance and delivery, in social functioning, pair bonding and affiliative behavior. Actual and future treatments for neurohypophysis related disorders are also discussed, particularly focusing on the development of new therapeutic compounds and patents.

A case of transient central diabetes insipidus after aorto-coronary bypass operation

Diabetes insipidus (DI) is characterized by excessive urination and thirst. This disease results from inadequate output of antidiuretic hormone (ADH) from the pituitary gland or the absence of the normal response to ADH in the kidney. We present a case of transient central DI in a patient who underwent a cardiopulmonary bypass (CPB) for coronary artery bypass grafting (CABG). A 44-yr-old male underwent a CABG operation. An hour after the operation, the patient developed polyuria and was diagnosed with central DI. The patient responded to desmopressin and completely recovered five days after surgery. It is probable that transient cerebral ischemia resulted in the dysfunction of osmotic receptors in the hypothalamus or hypothalamus-pituitary axis during CPB. It is also possible that cardiac standstill altered the left atrial non-osmotic receptor function and suppressed ADH release. Therefore, we suggest that central DI is a possible cause of polyuria after CPB.

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.

Desmopressin-induced posterior reversible encephalopathy syndrome

We herein report the case of a patient who presented with an acute decrease of visual acuity, hypertension, focal seizures and transient mental dysfunction while undergoing desmopressin treatment. Neuroimaging revealed bilateral occipital-parietal lesions that presented with vasogenic edema. After controlling the hypertension and discontinuing the desmopressin treatment, the patient's condition improved. A follow-up imaging examination performed six months later showed complete resolution of the lesions. It is important to recognize posterior reversible encephalopathy syndrome (PRES) as a rare and serious complication of desmopressin administration. Both the blood pressure and water electrolyte balance should be carefully monitored in patients receiving desmopressin therapy.

Desmopressin duration of antidiuretic action in patients with central diabetes insipidus

The key question answered by this study is whether it is possible to deliver a pharmacokinetic and pharmacodynamic duration of antidiuretic action long enough to ensure adequate antidiuresis with two daily administrations of desmopressin in patients with central diabetes insipidus (CDI). We studied the efficacy and safety of desmopressin i.v. in 13 CDI patients using two 3-way crossover designs, in the doses 30, 60, 125 ng, and 125, 250 and 500 ng. Duration of action, minimum output rate, max osmolality and average osmolality during action (AUC osmolality) were measured every 30 min for the first 2 h during the infusion, and then every hour or every second hour until the urine output rate was greater than 2 ml/kg/30 min. The duration of antidiuretic action was 4, 8 and 11 h, respectively, for 125, 250, and 500 ng, increasing from 250 to 500 ng but for the remaining secondary dynamic efficacy parameters no difference could be detected based on descriptive statistics between the doses 250 and 500 ng, indicating that the upper plateau region of the dose-response curve had been reached. All treatment emergent adverse events were classified as unrelated or unlikely related to trial medication. No serious adverse events occurred. Data on duration of action indicates that it is possible to achieve antidiuretic control with 500 ng i.v. corresponding to 160 μg orodispersible tablets twice daily in CDI patients. Today, the Minirin Melt label recommends the majority of CDI patients a dose of 60 to 120 μg t.i.d.

Familial neurohypophyseal diabetes insipidus due to a novel mutation in the arginine vasopressin-neurophysin II gene

BACKGROUND

Familial neurohypophyseal (central) diabetes insipidus (DI) is caused by mutations in the arginine vasopressin-neurophysin II (AVP-NPII) gene. The majority of cases is inherited in an autosomal dominant way. In this study, we present the clinical features of a mother and her son with autosomal dominant neurohypophyseal DI caused by a novel mutation.

CASE

A thirty-four-year-old woman and her three-year-old son were evaluated because of polyuria and polydipsia since the age of 1.5 years onwards. Both patients were subjected to a water deprivation test confirming the diagnosis of central DI. Magnetic resonance imaging of the brain of the mother showed a hypothalamus without apparent abnormalities and a relatively small neurohypophysis without a hyperintense signal. Mutation analysis showed a c.322G>T (p.?/p.Glu108X) in Exon 2 of the AVP-NPII gene in both mother and son.

DISCUSSION

This study reports neurohypophyseal DI in a mother and her son due to a novel mutation in Exon 2 of the AVP-NPII gene. Clinical and pathophysiological aspects of this disease are shortly reviewed and discussed.