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.

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.

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.

Central Diabetes Insipidus in the Background of Lithium Use: Consider Central Causes Despite Nephrogenic as the Most Common.

BACKGROUND Nephrogenic diabetes insipidus is a well-known adverse effect of lithium use. Albeit rare, there have also been documented cases of central diabetes insipidus (CDI) associated with lithium use. CASE REPORT A 31-year-old woman with a past medical history of bipolar disorder, managed with lithium 300 mg by mouth every day for 3 years, was assessed for a 1-year history of polyuria with accompanying polydipsia. During her initial hospital stay, her estimated urine output was more than 4 L per day. Initial labs showed elevated serum sodium (149 mmol/L; reference range 135-145), elevated serum osmolality (304 mOsm/kg; reference range 275-295), urine osmolality of 99 mOsm/kg (reference range 50-1200), and urine specific gravity (1.005; reference range 1.005-1.030). Lithium was at a subtherapeutic level of 0.05 mEq/L (reference range 0.6-1.2). Magnetic resonance imaging of the brain revealed no abnormalities of the pituitary gland. Two different occasions of desmopressin administration resulted in >50% increase in urine osmolality, confirming the diagnosis of CDI. Common causes of CDI, including trauma, tumors, and familial CDI, were ruled out and chronic lithium use was determined as the most probable cause for the patient's CDI. CONCLUSIONS CDI in the background of chronic lithium use is rarely reported. We present this case to consider CDI as a differential diagnosis when evaluating polyuria and hypernatremia in patients with long-term lithium use. These presentations warrant the consideration of both types of diabetes insipidus in the differential diagnoses.

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.

Central diabetes insipidus with anti-rabphilin-3A antibody positivity causing hypovolemic shock after resection of tumorous lesions in the pelvic cavity.

A 36-year-old female was pointed out to have liver enzyme elevation by routine health checkup. Subsequent contrast-enhanced CT scan identified gigantic uterine fibroids and retroperitoneal tumor. She was referred to the gynecologist at JA Toride Medical Center and planned to undergo a uterus enucleation and biopsy of the retroperitoneal tumor. The surgery was conducted without any troubles. After the surgery, the patient presented polyuria with urine volume 10-20 L a day and developed hypovolemic shock. Laboratory test revealed hypotonic urine and hypernatremia. Arginine vasopressin (AVP) loading test suggested shortage of endogenous vasopressin. Since the subcutaneous administration of AVP was not sufficient to control the urine volume, continuous intravenous infusion of AVP was initiated. After achieving hemodynamic stability, the treatment was switched to oral desmopressin. MRI finding indicated attenuation of high signal in posterior pituitary in T1 weighted image while neither enlargement of pituitary nor thickening of pituitary stalk was indicated by enhanced MRI. Hypertonic salt solution test indicated no responsive elevation of AVP, confirming the diagnosis of central diabetes insipidus (CDI). Her anterior pituitary function was preserved. Only anti-rabphilin-3A antibody was found positive in the serum of the patient, while other secondary causes for CDI were denied serologically and radiologically. Hence, lymphocytic infundibuloneurohypophysitis　(LINH) was suspected as the final diagnosis. Hormonal replacement therapy by nasal desmopressin was continued and the patient managed to control her urine volume. In cases of CDI considered idiopathic with conventional examinations, anti-rabphilin-3A antibody may be a clue for determining the cause as LINH.

Delay in desmopressin therapy: Disaster in waiting.

WHAT IS KNOWN AND OBJECTIVE: Central diabetes insipidus (DI) is a complex disease that requires firm adherence to desmopressin therapy. There is little information on the onset of hypernatremia after withdrawal of desmopressin. CASE SUMMARY: We present a case of an elderly woman with central DI whose serum sodium jumped from 141 to 171 mEq/L after 48-72 h of holding oral desmopressin. Her DI crisis resolved with intravenous desmopressin and free water administration. WHAT IS NEW AND CONCLUSION: Based on this precipitous onset of DI crisis, we recommend not withholding desmopressin for more than 24 h.

[Diagnosis and tactics of managing a patient with central diabetes insipidus on the example of a clinical case].

Diagnosis and differential diagnosis of patients with diabetes insipidus is often a difficult task for the endocrinologist. This case report focuses on a patient with a long history of central idiopathic diabetes insipidus who had a substantial decrease in desmopressin requirements during the last year of follow-up. Conducting tests with osmotic stimulation (test with water deprivation, infusion test with hypertonic solution) made it possible to answer the question of the persistence of the disease, as well as to determine a further management plan, taking into account the physiological characteristics of our patient.

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.

[Permanent central diabetes insipidus after traumatic brain injury. Case report and literature review]. / Razvitie postoyannogo tsentral'nogo nesakharnogo diabeta posle travmaticheskogo povrezhdeniya golovnogo mozga. Klinicheskii sluchai i obzor literatury.

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.

Secondary autoimmune hypothalamitis with severe memory impairment 7 years after the onset of diabetes insipidus due to lymphocytic hypophysitis: a case report.

BACKGROUND: Autoimmune hypothalamitis is a very rare neuroendocrine disorder that causes central diabetes insipidus, headache, visual impairment, and sometimes cognitive impairment. Autoimmune hypothalamitis may occur in association with autoimmune hypophysitis, including lymphocytic hypophysitis, or in isolation. It is not known whether autoimmune hypothalamitis and autoimmune hypophysitis are consecutive diseases. CASE PRESENTATION: A 52-year-old woman developed autoimmune hypothalamitis 7 years after developing central diabetes insipidus due to lymphocytic hypophysitis, resulting in severe memory impairment. High-dose intravenous methylprednisolone therapy improved her cognitive function and decreased the size of the lesion. CONCLUSION: This case presented a unique clinical course, with a long period of time between the onset of autoimmune hypopituitaritis and the development of autoimmune hypothalamitis.

Venous thromboembolism in the setting of pediatric central diabetes insipidus: a systematic review of the literature and report of 2 cases.

OBJECTIVE: Central diabetes insipidus (DI) is frequently identified preoperatively and/or postoperatively in patients with sellar or parasellar lesions. Early diagnosis and effective perioperative management of central DI is critical to minimize disruptions in fluid homeostasis. In particular, although venous thromboembolism (VTE) is generally less common in pediatric patients than their adult counterparts, isolated reports suggest that VTE occurs at a higher frequency in pediatric patients with central DI. METHODS: Using the PubMed, Scopus, and Springer Link databases, the authors performed a systematic review of the literature with regard to the incidence of VTE in pediatric patients with central DI. Inclusion criteria were availability of the full text in English, diagnosis of central DI and VTE in the same patient, and pediatric age defined as ≤ 21 years. Data were reported as median and interquartile range for continuous variables and as frequencies and percentages for categorical variables. Risk of bias assessments of the individual studies were performed using the Joanna Briggs Institute Critical Appraisal Checklists for case series and case reports. RESULTS: Of 2094 search results, 12 articles met the inclusion criteria and described a total of 17 cases of VTE in pediatric patients with central DI. Two additional patients from the authors' institution were added to this cohort. The underlying pathologies included craniopharyngioma (n = 6), suprasellar germinoma (n = 4), epileptic encephalopathy (n = 2), pilocytic astrocytoma (n = 2), prolactinoma (n = 2), Cushing disease (n = 1), failure to thrive (n = 1), and congenital hypothalamic syndrome (n = 1). Thrombotic complications included deep vein thrombosis (n = 10 [53%]), cerebral venous sinus thrombosis (n = 6 [32%]), pulmonary embolism (n = 4 [21%]), inferior vena cava thrombosis (n = 2 [11%]), and disseminated intravascular coagulation (n = 1 [5%]). There was a 26% mortality rate. CONCLUSIONS: VTE is a rare but potentially devastating postoperative complication that appears to have a higher incidence among patients with central DI. Although this review was limited by heterogeneous information across limited reports, pediatric neurosurgical patients with DI may benefit from more aggressive VTE surveillance and prophylaxis.

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.

Variability in Oral Desmopressin Dose Requirements in Children with Central Diabetes Insipidus.

There is inconsistency in the amount of oral desmopressin that children with central diabetes insipidus require. We investigated whether clinical characteristics influenced desmopressin dose requirements in 100 children with central diabetes insipidus. Extremely large doses were associated with acquired etiology (P = .04), greater body mass index z score, intact thirst, and additional pituitary hormone deficiencies (P < .001).

Anti-PD-1 treatment-induced immediate central diabetes insipidus: a case report.

Modulating PD-1 expression can constrain tumor growth. Hodgkin's lymphoma patients commonly express PD-L1 on tumor cells. We report the case of a 60-year-old male patient with relapsed classical Hodgkin's lymphoma who suffered from immediate-onset chill, hyperthermia and polyuria following initial treatment with sintilimab, an anti-PD-1 monoclonal antibody. The results revealed central diabetes insipidus (cDI). After 3 months of treatment with glucocorticoids and desmopressin acetate, his symptoms and the results were consistent with the resolution of cDI and the treatment course was discontinued. Diabetes insipidus is a rare complication of immunotherapeutic treatment, and this is the first case report to our knowledge to have described immediate-onset cDI caused by anti-PD-1 treatment.

Lay abstract For relapsed classical Hodgkin's lymphoma, anti-PD-1 monoclonal antibodies have been related to potent safety profiles and efficacy. Reported here is a case of a 60-year-old man diagnosed as having relapsed classical Hodgkin's lymphoma. He achieved a durable response over 4 months with four rounds of traditional chemotherapy, and then the disease relapsed. Sintilimab, an anti-PD-1 monoclonal antibody, was executed for salvage therapy. In spite of the patient-acquired durable response, central diabetes insipidus was detected after the first application of sintilimab. According to our knowledge this is the first case to report immediate-onset central diabetes insipidus caused by the treatment of anti-PD-1. In the present study, we discussed and analyzed the types and clinical causes of diabetes insipidus for this patient.

Perioperative management of cranial diabetes insipidus in a patient requiring a tracheostomy.

Cranial diabetes insipidus (DI), which can cause life-threatening dehydration, is treated with desmopressin, often intranasally. This is challenging in patients whose nasal airflow is altered, such as those requiring tracheostomy. We report the case of a patient, taking intranasal desmopressin for cranial DI, who underwent partial glossectomy, free-flap reconstruction and tracheostomy. Postoperatively, she could not administer nasal desmopressin due to reduced nasal airflow. She developed uncontrollable thirst, polyuria and hypernatraemia. Symptoms were relieved by switching to an enteric formulation. A literature review showed no cases of patients with DI encountering difficulties following tracheostomy. The Royal Society of Endocrinology recommends perioperative planning for such patients, but gives no specific guidance on medication delivery in the context of altered airway anatomy. Careful perioperative planning is required for head and neck patients with DI, particularly for those undergoing airway alteration that may necessitate a change in the mode of delivery of critical medications.