先天性腎性尿崩症

BACKGROUND: Nephrogenic diabetes insipidus (NDI) is characterized by impaired renal responsiveness to arginine vasopressin, causing defective urinary concentration and large volumes of dilute urine. Long-term lithium exposure is an important acquired cause. Perioperative fasting, restricted free-water intake, and ongoing fluid losses may unmask compensated lithium-associated urinary concentrating dysfunction and precipitate severe hypernatremia. CASE PRESENTATION: A 61-year-old man underwent laparoscopic resection of a pancreatic tail lesion. His history included schizophrenia, type 2 diabetes mellitus, impaired renal function, long-term lithium therapy, and preoperative polyuria, nocturia, and polydipsia. Preoperative serum sodium was 147.1 mmol/L, creatinine 174.4 μmol/L, and eGFR 35.6 mL/min. Postoperatively, restricted free-water intake was followed by progressive polyuria, persistent negative fluid balance, altered mental status, and worsening renal function. Urine output peaked at 7,900 mL/24 h and serum sodium at 165.5 mmol/L. Despite marked hypernatremia and hypertonicity, urine specific gravity remained ≤1.005. Serum lithium before discontinuation was 0.90 mmol/L. Based on long-term lithium exposure, preoperative symptoms, persistent polyuria, recurrent severe hypernatremia, and low urine specific gravity, probable lithium-associated NDI was considered. Because urine osmolality and a standardized desmopressin response test were unavailable, NDI could not be biochemically confirmed and central diabetes insipidus could not be definitively excluded. Hyperglycemia, gastrointestinal fluid losses, and renal dysfunction may also have contributed. MANAGEMENT AND OUTCOME: Lithium was discontinued after psychiatric and multidisciplinary consultation, and hydrochlorothiazide was initiated. Treatment included gradual free-water replacement, intravenous fluid adjustment, sodium restriction, enteral free water administered separately from enteral nutrition, and close monitoring of serum sodium, potassium, renal function, urine output, glucose, and mental status. The retrospectively estimated free-water deficit was approximately 7.5 L. With combined management, serum sodium, urine output, and consciousness gradually improved. At 12 weeks, serum sodium was 142.3 mmol/L. At 13 months, urine specific gravity remained 1.004, although persistent NDI could not be confirmed. CONCLUSIONS: In patients receiving long-term lithium, postoperative polyuria, recurrent hypernatremia, and low urine specific gravity should prompt consideration of lithium-associated urinary concentrating dysfunction while other causes of water loss are assessed. Careful perioperative medication review, sodium and fluid-balance monitoring, individualized fluid management, and multidisciplinary collaboration are essential.

Hypernatremia due to polyuria following cardiac surgery is rare. We report a case that required to identify the cause of massive polyuria. A 50-year-old male underwent aortic arch replacement for acute aortic dissection. Early postoperatively, he developed marked polyuria [over 3,000 ml within 6 hours after intensive care unit (ICU) admission, over 15,000 ml within 24 hours] and hypernatremia (peak value 187 mEq/l). We first assumed vasopressin deficiency due to cardiopulmonary bypass, and desmopressin nasal spray was somewhat effective. Continuous vasopressin infusion combined with massive 5 % glucose infusion started to reduce serum sodium value to 160 mEq/l. Neither a vasopressin challenge test on post operative day 16 nor a water restriction test on post operative day 48 demonstrated an increase in urine osmolality, leading to a diagnosis of nephrogenic diabetes insipidus. This case highlighted the complexity of fluid management when nephrogenic diabetes insipidus complicates postoperative course after surgery using cardiopulmonary bypass.

In this case report, a 57-year-old man with bipolar disorder on long-term lithium treatment was admitted with catatonia. Laboratory tests revealed hypercalcemia with parathyroid hormone levels in the upper third of the normal reference interval, consistent with lithium-associated hyperparathyroidism, as well as nephrogenic diabetes insipidus. Pausing lithium and treating hypercalcemia led to a gradual improvement in catatonia. The case emphasises the importance of considering endocrine and electrolyte disturbances in cases of acute deterioration of psychiatric symptoms during lithium treatment.

Catatonia is a neuropsychiatric syndrome characterized by disturbances in motor activity, affect, and autonomic function. Although often associated with primary mood or psychotic disorders, it can be precipitated or sustained by systemic infections such as urinary tract infection (UTI). We describe a 60-year-old man with recurrent catatonia and diagnoses of schizophrenia, bipolar disorder, and major neurocognitive disorder, whose latest episode of catatonia, described in this case report, was preceded by psychosocial stress and appeared to be exacerbated by polymicrobial UTI, bacteremia, and urosepsis. He had a history of neuroleptic malignant syndrome (NMS) and an inconsistent response to electroconvulsive therapy (ECT), limiting usual first-line treatment options. During this admission, he developed Klebsiella pneumoniae UTI with Staphylococcus simulans bacteremia and later Pseudomonas aeruginosa urosepsis, in the context of mixed central and nephrogenic diabetes insipidus likely related to long-term lithium therapy. The patient's catatonia proved refractory to very high-dose lorazepam but improved with an intensive, multimodal regimen including intravenous (IV) benzodiazepines (diazepam, midazolam), enteral and subsequently oral lorazepam, zolpidem, memantine, and aggressive treatment of infection and electrolyte abnormalities. He ultimately regained baseline function and was discharged on a slow taper of benzodiazepines and zolpidem. This case illustrates the bidirectional relationship between infection, autonomic and immune dysregulation, and catatonia; highlights practical challenges when treatment with benzodiazepines and ECT is constrained by medical comorbidity; and supports considering adjunctive GABAergic and glutamatergic agents in carefully selected cases of refractory catatonia, under close specialist supervision.

Background Polyuria-polydipsia syndrome encompasses a heterogeneous group of disorders, including central diabetes insipidus (CDI), nephrogenic diabetes insipidus (NDI), and primary polydipsia. Despite presenting with similar clinical manifestations, these conditions differ markedly in their underlying pathophysiology, prognosis, and management. Distinguishing between them remains clinically challenging, particularly in patients with partial disease and in resource-limited settings where newer diagnostic biomarkers such as copeptin are not routinely available. This study highlights the diagnostic complexity and diverse etiologies of polyuria-polydipsia syndrome through a retrospective case series. Methods We conducted a retrospective observational study of patients presenting with polyuria-polydipsia syndrome at a tertiary care center over a five-year period. Clinical, biochemical, and radiological data were retrieved from medical records. Patients underwent diagnostic evaluation based on clinical indication, including assessment of serum and urine osmolality and a supervised water deprivation test with or without a desmopressin challenge, as appropriate. Additional imaging and genetic investigations were performed where clinically indicated. Patients were classified as having CDI, NDI, or primary polydipsia based on the available clinical, biochemical, radiological, and, where applicable, genetic findings in accordance with standard diagnostic criteria. Results A total of seven patients were included, demonstrating diverse etiologies: complete CDI (n = 1), CDI associated with pituitary stalk interruption syndrome (n = 1), partial CDI (n = 1), NDI with a possible CLCN5 gene variant (n = 1), primary polydipsia (n = 1), pheochromocytoma presenting as a diabetes insipidus mimic (n = 1), and CDI secondary to postoperative and post-radiotherapy craniopharyngioma with panhypopituitarism (n = 1). Despite similar presenting complaints, each case exhibited distinct biochemical and radiological profiles. The water deprivation test followed by a desmopressin challenge enabled definitive diagnosis. Etiology-specific management resulted in significant clinical improvement across the cohort. Conclusion Polyuria-polydipsia syndrome represents a diagnostically challenging entity with diverse underlying etiologies. A structured approach integrating clinical evaluation, biochemical testing, dynamic assessment, and imaging remains effective for accurate diagnosis, even in the absence of advanced biomarkers. Recognition of atypical and reversible causes is essential to avoid misdiagnosis and ensure appropriate, targeted management.