Abstract Disclosure: M. Shrivastava: None. L. Kaur: None. B. Armendariz: None. R. Kaur: None. A. Shetty: None. In patients with end stage renal disease (ESRD), hypoglycemia accounts for up to 3.6% of all the admissions with mortality rates of up to 30%. A combination of impaired insulin clearance, changes in glucose metabolism and dialysis process makes the patients with end stage renal disease vulnerable to neuroglycopenia.Case description:53 year old female with past medical history of insulin dependent type 2 diabetes mellitus, ESRD secondary to diabetes, on hemodialysis(HD) thrice weekly since two years, presented to the emergency with altered mental status, respiratory distress, tachycardia. Lab work revealed blood glucose(BG) of 23 mg/dl, HbA1c of 8.4%, eGFR of 6, and arterial blood gas showed hypercapnic respiratory acidosis. Patient received dextrose, with no improvement of symptoms. Eventually she developed acute hypercapnic respiratory failure requiring endotracheal intubation with mechanical ventilation, and was transferred to the ICU. As per family, a night prior to presentation, last recorded BG after dinner was 253 mg/dl, she took her night time glargine, which was recently increased by her primary care for poorly controlled HbA1c levels. Brain MRI and long term EEG monitoring findings were consistent with underlying extensive brain injury secondary to prolonged hypoglycemia. Unfortunately, the patient's condition did not improve despite HD and BG correction, eventually she underwent compassionate extubation. Case Discussion:The insulin requirements in ESRD patients are reduced by approximately 50%, regardless of residual insulin secretion. Malnutrition and acidosis reduce hepatic glycogen stores and availability of gluconeogenic precursor, expected compensatory renal gluconeogenesis is compromised by decreased renal function causing hypoglycemia, which is further worsened by inappropriately high plasma insulin levels caused by reduced renal insulin breakdown. Diabetes mellitus patients with ESRD are frequently managed with basal-bolus insulin regimen, and HD up to thrice weekly, leaving them without HD for up to 3 days especially over the weekend. This can result in accumulation of insulin metabolites causing delayed insulin clearance as seen in our patient. In such cases even long acting insulin, such as glargine, can have compounding effects, which could possibly cause fatal complications such as neuroglycopenia. In such patients continuous glucose monitor use with tapering dose glargine regimen may help eliminate this compounding effect. Conclusion: Neuroglycopenia is a rare manifestation of diabetes mellitus with ESRD. Compromised renal gluconeogenesis and impaired insulin clearance can cause inappropriately high plasma levels of insulin. In such patients continuous glucose monitoring along with tapering dose of long acting insulin should be utilized for proper glycemic control to limit compounded effect of insulin metabolite accumulation. Presentation: 6/3/2024