Endocrine Abstracts

Background: Arginine vasopressin deficiency (AVP-D), is a recognized complication of surgery for suprasellar tumours such as craniopharyngioma, where disruption of the hypothalamic–neurohypophyseal axis may occur. AVP-D manifests with polyuria, polydipsia, and risk of profound hypernatraemia if fluid intake is insufficient or desmopressin therapy is suboptimal. Management is particularly challenging in patients with cognitive impairment, as in this case, where self-regulation of fluid balance was compromised, necessitating careful biochemical monitoring, medication titration, and family or carer support.

Case Summary: We present a case of 43-year-old woman with a history of adamantinomatous craniopharyngioma, initially diagnosed in Nigeria, complicated by hydrocephalus requiring bilateral ventriculoperitoneal shunts (2022). She subsequently underwent cyst debulking at our centre in May 2025 after radiological progression & clinical decline. Post-operatively, she developed persistent AVP-D, presenting with polyuria & recurrent hypernatraemia (peak 176 mmol/l), necessitating multiple hospital admissions & desmopressin dose adjustments. Four weeks later, she was re-admitted with confusion and diagnosed with hyperosmolar hyperglycaemic state (HHS), with sodium of 176 mmol/l & serum osmolality of 413 mmol/kg, precipitated by infection. She was initially started on insulin alongside glimepiride for newly diagnosed type 2 diabetes, with good response and improvement in HbA1 c from 72 to 49 mmol/mol. She has since been weaned off insulin & is currently maintained on glimepiride alone. Subsequent endocrine follow-up revealed evolving panhypopituitarism with secondary adrenal insufficiency, central hypothyroidism, and hypogonadism, for which she was optimized on oral hormone replacement. Further inquiry revealed that she had an ongoing neurocognitive decline, over several years, manifesting as poor short-term memory, disorientation, and reduced ability to perform daily activities. This had been compounded by treatment burden & social challenges, particularly childcare responsibilities. Social care support, neurorehabilitation, and psychological input have been central to her ongoing care alongside endocrine & neurosurgical follow-up.

Discussion points: 1. Management of AVP-D – This case underscores the difficulty in balancing desmopressin dosing & fluid intake, especially when cognitive impairment limits self-management. Early recognition of hypernatraemia & close electrolyte monitoring are critical. 2. Metabolic complications – The development of HHS illustrates the increased risk of metabolic decompensation in patients with complex neuroendocrine disease. Coordinated diabetes input is essential to reduce morbidity & hospitalizations. 3. Neurocognitive and psychosocial impact – Beyond medical stabilization, quality of life and functional independence are major concerns. This case highlights the complexity of managing post-surgical AVP-D in a patient with multiple pituitary hormone deficits, metabolic complications, and cognitive impairment, emphasizing the need for a multidisciplinary approach.