Psychiatric symptoms and limb tremors associated with central pontine myelinolysis: A case of alcoholism without hyponatremia

Osmotic demyelination as a complication of hyponatremia correction: a systematic review

BACKGROUND

Rapid correction of hyponatremia, especially when severe and chronic, can result in osmotic demyelination. The latest guideline for diagnosis and treatment of hyponatremia (2014) recommends a correction limit of 10 mEq/L/day. Our aim was to summarize published cases of osmotic demyelination to assess the adequacy of this recommendation.

METHOD

Systematic review of case reports of osmotic demyelination. We included cases confirmed by imaging or pathology exam, in people over 18 years of age, published between 1997 and 2019, in English or Portuguese.

RESULTS

We evaluated 96 cases of osmotic demyelination, 58.3% female, with a mean age of 48.2 ± 12.9 years. Median admission serum sodium was 105 mEq/L and > 90% of patients had severe hyponatremia (<120 mEq/L). Reports of gastrointestinal tract disorders (38.5%), alcoholism (31.3%) and use of diuretics (27%) were common. Correction of hyponatremia was performed mainly with isotonic (46.9%) or hypertonic (33.7%) saline solution. Correction of associated hypokalemia occurred in 18.8%. In 66.6% of cases there was correction of natremia above 10 mEq/L on the first day of hospitalization; the rate was not reported in 22.9% and in only 10.4% was it less than 10 mEq/L/day.

CONCLUSION

The development of osmotic demyelination was predominant in women under 50 years of age, with severe hyponatremia and rapid correction. In 10.4% of cases, there was demyelination even with correction <10 mEq/L/day. These data reinforce the need for conservative targets for high-risk patients, such as 4-6 mEq/L/day, not exceeding the limit of 8 mEq/L/day.

A rare presentation of central pontine myelinolysis secondary to hyperglycaemia

BACKGROUND

Central pontine myelinolysis (CPM) is a rare demyelinating disorder caused by the loss of myelin in the center of the basis pontis. CPM typically occurs with rapid correction of severe chronic hyponatremia and subsequent disturbances in serum osmolality. Although hyperglycaemia is recognized as a pathogenetic factor in serum osmolality fluctuations, CPM is rarely seen in the context of diabetes.

CASE PRESENTATION

A 66-year-old Chinese male presented with a history of gait imbalance, mild slurred speech and dysphagia for two weeks. MRI showed the mass lesions in the brainstem, and laboratory examinations showed high blood glucose and HbA1c, as well as increased serum osmolality. The patient was diagnosed with CPM secondary to hyperosmolar hyperglyceamia and received insulin treatment as well as supportive therapy. After six weeks of followup, the patient had fully recovered to a normal state.

CONCLUSION

CPM is a potentially fatal neurological condition and can occur in uncontrolled diabetes mellitus. Early diagnosis and timely treatment are crucial for improving the prognosis.

Rapid Correction of Hyponatremia With Isotonic Saline Leading to Central Pontine Myelinolysis

Central pontine myelinolysis (CPM) is a part of the spectrum of osmotic demyelination syndrome (ODS), which is a rare demyelinating disorder due to the rapid correction of low serum sodium. It affects the neurons of the pons but may also involve other extra-pontine sites. The disease is characterized by a wide variety of clinical features ranging from dysarthria, dysphagia, bulbar palsy, quadriplegia, and behavioral and psychiatric disturbances. We present a case of a young female who developed CPM due to rapid sodium correction after vomiting. She presented with quadriplegia and locked-in syndrome. The diagnosis is on the basis of clinical and radiographic features. Magnetic resonance imaging (MRI) of the brain is superior to computed tomography (CT) in detecting changes. It shows hyperintensities on T2-weighted images that are classically known as the trident sign in the region of the pons. The patient was managed supportively, and the family was counseled regarding the poor prognosis of the disease. Unfortunately, she met a fatal fate due to a complication of CPM that is aspiration pneumonia. It is, therefore, imperative to create more awareness regarding the disease, and measures should be taken for its prevention that includes correction of low sodium levels not greater than 10 mmol/L/day.