Atypical presentation of central pontine myelinolysis in hyperglycemia

Central pontine myelinolysis (CPM) usually occurs with rapid correction of severe chronic hyponatremia. Despite the pronounced fluctuations in serum osmolality, CPM is rarely seen in diabetics. This is a case report of CPM associated with hyperglycemia. A 45-year-old non-smoking and non-alcoholic African American male with past medical history of type 2 diabetes, hypertension, stage V chronic kidney disease and hypothyroidism presented with a two-week history of intermittent episodes of gait imbalance, slurred speech and inappropriate laughter. Physical examination including complete neurological assessment and fundoscopic examination were unremarkable. Laboratory evaluation was significant for serum sodium: 140 mmol/L, potassium: 3.9 mmol/L, serum glucose: 178 mg/dL and serum osmolality: 317 mosmol/kg. His ambulatory blood sugars fluctuated between 100 and 600 mg/dL in the six weeks prior to presentation, without any significant or rapid changes in his corrected serum sodium or other electrolyte levels. MRI brain demonstrated a symmetric lesion in the central pons with increased signal intensity on T2- and diffusion-weighted images. After neurological consultation and MRI confirmation, the patient was diagnosed with CPM secondary to hyperosmolar hyperglycemia. Eight-week follow-up with neurology was notable for near-complete resolution of symptoms. This case report highlights the importance of adequate blood glucose control in diabetics. Physicians should be aware of complications like CPM, which can present atypically in diabetics and is only diagnosed in the presence of a high index of clinical suspicion. LEARNING POINTS: Despite the pronounced fluctuations in serum osmolality, central pontine myelinolysis (CPM) is rarely seen in diabetics. This case report of CPM associated with hyperglycemia highlights the importance of adequate blood glucose control in diabetics. Physicians should be aware of complications like CPM in diabetics. CPM can present atypically in diabetics and is only diagnosed in the presence of a high index of clinical suspicion.