Central Pontine Myelinolysis in a Normonatremic Patient with Depression

Osmotic Demyelination Syndrome in the Setting of Normonatremia: A Case Report and Review of the Literature

Osmotic demyelination syndrome (ODS) is a rare complication associated with rapid sodium changes, typically encountered in patients with severe hyponatremia. ODS in patients with normonatremia (ODSIN) is less recognized. We describe a patient with MRI-detected ODSIN following neurotrauma and reviewed the relevant literature. We present a 57-year-old female with subdural hematoma following ground-level fall. Her initial sodium was 140 mEq/L but over 2 days, rose 17 mEq/L, peaking at 157 mEq/L. On exam, unexplainable, unexpected left-sided hemiplegia with weakness sparing her face were noted; ODS was suspected. MRI revealed central pontine T2 hyperintensity, T1 hypointensity, and FLAIR hyperintensity. Treatment included gradual lowering of sodium with normal saline and free water. She was discharged to a skilled nursing facility (SNF) with sodium 138 mEq/L and upon 4-year follow-up had moderate disability and required some assistance to support activities of daily living. Our literature search yielded 23 cases (22 normonatremic; 1 where normonatremia progressed to hypernatremia). Common signs/symptoms were hyperreflexia, dysarthria, and gait disturbance. Common comorbidities were alcoholism, dialysis, and renal disease/failure. Cranial MRI confirmed all cases, frequently revealing central pontine T2 and FLAIR hyperintensity and T1 hypointensity. Our review further characterizes the diverse etiologies, clinical course, and radiographic features of ODSIN. Clinicians should consider this diagnosis when neurological symptoms occur even in the setting of normonatremia.

Symptomatic and asymptomatic pontine hyperintensities: are they central pontine myelinolysis? Case series

The diagnosis of central pontine hyperintensities on cranial magnetic resonance imaging has wide-spectrum clinical entities, and the pro-type diagnosis of these is central pontine myelinolysis. The rapid changes in extracellular environment due to an imbalance of electrolytes or metabolic or toxic stress to the myelin sheath can cause demyelination of white matter tracts in pons, which is why this situation could have different etiologies than just rapid sodium changes. Central pontine myelinolysis can be presented with different clinical scenarios from asymptomatic to death. Here, we present eight patients who had central pontine hyperintensities on radiological imaging but showed various clinical symptoms and different etiologies. The etiologies of these cases are hypertriglyceridemia, alcohol consumption, antidepressant usage, immunocompromised situations, uncontrolled diabetes mellitus, liver and kidney failure, electrolyte changes, and adrenal insufficiency. We aimed to take attention with this case series to the fact that not only fast correction of hyponatremia is the cause of central pontine myelinolysis, but also different etiologies could play a role in this situation, and making the central pontine myelinolysis diagnosis considering different diagnosis is very important.

Osmotic Demyelination Syndrome in a High-Risk Patient Despite Cautious Correction of Hyponatremia

Hyponatremia is a common electrolyte disorder requiring careful management to prevent severe complications. Osmotic demyelination syndrome (ODS) is a serious neurological disorder that can develop from rapid correction of hyponatremia. Herein, is a description of the case of a 61-year-old man with multiple risk factors, including alcoholism, hypokalemia, malnutrition, and alcoholic liver cirrhosis, who developed ODS despite adherence to the recommended correction rate for hyponatremia. The patient presented to the emergency department with generalized weakness, gait disturbance, and decreased muscle strength. Initial laboratory investigations revealed severe hyponatremia, hypokalemia, and dehydration. The patient was treated with cautious correction of the hyponatremia below 8 mmol/L per day. However, on the seventh hospital day, he developed tremors, rigidity, and decreased consciousness and was diagnosed with osmotic demyelination syndrome. Despite receiving general supportive care, desmopressin, and dextrose 5% in water to reduce the serum sodium levels, the patient did not show significant improvement and was transferred to a nursing home for long-term conservative care on day 35 of hospitalization. This case report highlights the challenges associated with the diagnosis and management of osmotic demyelination syndrome and the importance of identifying patients at high risk of developing this neurological disorder.