Central pontine and extrapontine myelinolysis. Recent data and management in the intensive care unit

Abstract

Central pontine myelinolysis (CPM) and extrapontine myelinolysis (EPM), also known as the osmotic demyelination syndrome, are uncommon disorders, characterized by non-inflammatory demyelination involving the pons and other areas of the central nervous system. Usual predisposing factors are chronic alcoholism, malnutrition, and correction of hyponatremia. Clinical features are variable and depend on the involved brain regions. The usual CPM/EPM presentation includes tetraparesia, locked-in syndrome, abnormal movements, and psychiatric symptoms. Diagnosis is based on neuroimaging, especially magnetic resonance imaging, which shows typically hypointense lesions on T1-weighted sequences and hyperintense lesions on T2-weighted sequences. Supportive treatment is all that can be recommended. No specific treatment has been proven effective. Although earlier reports on CPM/EPM have shown very poor outcome, recent reports suggest better outcome with improved survival and recovery. However, no study has clearly identified any potential prognostic factors in CPM/EPM. Very few data are available for the most severely ill patients requiring mechanical ventilation. The uncertain benefits of aggressive and costly life-supporting treatments for these critically ill patients with severe comorbidities and neurologic impairment could have great influence on decision-making for the level of care. However, recovery is unpredictable on the basis of illness severity and decisions should not be influenced by the initial presentation since favorable outcome is possible.