Central Pontine Myelinosis and Osmotic Demyelination Syndrome

Abstract

smotic demyelination syndrome (ODS) was first described in 1959 by Adams and Victor, who reported "pontine myelinolysis" in alcoholic patients (1). On pathophysiological considerations, and as an increasing number of manifestation sites in addition to the pons were detected, central pontine myelinolysis (CPM) and extrapontine myelinolysis (EPM) were combined into "osmotic demyelination syndrome". Exact epidemiological data are still lacking, as there is not always a clear distinction between ODS and a prior or underlying disease. Furthermore, ODS is not always detected radiologically. As a result, the introduction of magnetic resonance imaging (MRI) led to increasing incidences of ODS, with the demonstration of oligosymptomatic as well as asymptomatic manifestations. Overall, ODS accounts for 0.4% to 0.56% of all neurological admissions to tertiary referral hospitals and 0.06% of all medical hospital admissions (2-4). MRI-based studies describe SummaryBackground: Osmotic demyelination syndrome (ODS), which embraces central pontine myelinolysis (CPM) and extrapontine myelinosis (EPM), is often underdiagnosed in clinical practice, but can be fatal. In this article, we review the etiology, pathophysiology, clinical features, diagnosis, treatment, and prognosis of ODS.Methods: Pertinent publications from the years 1959 to 2018 were retrieved by a selective search in PubMed.Results: The most common cause of ODS is hyponatremia; particular groups of patients, e.g., liver transplant recipients, are also at risk of developing ODS. The pathophysiology of ODS consists of cerebral apoptosis and loss of myelin due to osmotic stress. Accordingly, brain areas that are rich in oligodendrocytes and myelin tend to be the most frequently affected. Patients with ODS often have a biphasic course, the first phase reflecting the underlying predisposing illness and the second phase reflecting ODS itself, with pontine dysfunction, impaired vigilance, and movement disorders, among other neurological abnormalities. The diagnostic modality of choice is magnetic resonance imaging (MRI) of the brain, which can also be used to detect oligosymptomatic ODS. The current mainstay of management is prevention; treatment strategies for manifest ODS are still experimental. The prognosis has improved as a result of MRI-based diagnosis, but ODS can still be fatal (33% to 55% of patients either die or remain permanently dependent on nursing care). Conclusion:ODS is a secondary neurological illness resulting from a foregoing primary disease. Though rare overall, it occurs with greater frequency in certain groups of patients. Clinicians of all specialties should therefore be familiar with the risk constellations, clinical presentation, and prevention of ODS. The treatment of ODS is still experimental at present, as no evidence-based treatment is yet available.

Osmotic Demyelination Syndrome Despite Appropriate Hyponatremia Correction

“…The prognosis has improved significantly as a result of an MRI-based early diagnosis of CPM. However, it still can be fatal and 33% to 55% of patients can die or remain in a permanent vegetative state [6]. Among variable risk factors, chronic alcoholism is considered as the most common cause of ODS [7][8].…”

“…The prognosis of ODS has improved significantly because of an magnetic resonance imaging (MRI)based early diagnosis. However, 33% to 55% of patients can die or remain in a permanent vegetative state [6].…”

Aspectos prácticos para la clasificación, diagnóstico y manejo de hiponatremia en el paciente hospitalizado

“…Este fenómeno se conoce como SDO, suele generar síntomas 3-4 días después del evento y causando un compromiso neurológico variable con secuelas irreversibles 30 . También, se han identificado algunos factores de riesgo como: concentración de sodio menor a 105 mEq/L, consumo crónico de alcohol, desnutrición y enfermedad hepática avanzada 31 . Por lo anterior, es importante establecer metas seguras de corrección del sodio con el objetivo de mantener al paciente en un rango terapéutico, pero sin aumentar el riesgo de SDO.…”

Follow-Up of Brain Single-Photon Emission Computed Tomography (SPECT) and Magnetic Resonance Imaging (MRI) in a Case of Seizure Caused by Osmotic Demyelination Syndrome

“…Osmotic demyelination syndrome (ODS) is an uncommon neurological disorder found in about 0.4–0.56% of all neurological admissions in tertiary hospitals [ 1 – 3 ].…”