Cerebral encephalopathy with extrapontine myelinolysis in a case of postpartum hypernatremia

Abstract

Extrapontine myelinolysis, a fairly common metabolic disorder, is associated with neurological complications. Central pontine and extrapontine myelinolysis are commonly recognized with rapid correction of sodium. Myelinolysis, however, has rarely been described with hypernatremia. We report a rare case of post-partum hypernatremic encephalopathy associated with serum sodium levels as high as 200 mEq/l on presentation. Although the serum sodium levels were brought down gradually, subsequent imaging showed progression of demyelination and deterioration of the neurological status.

Keywords: Demyelination; encephalopathy; extrapontine myelinilysis hypernatremia; postpartum.

Figure 1(A and B)

MRI reveals hyperintense signal involving bilateral para-sagittal parietal regions, caudate nuclei, external capsules and thalami (arrows) on axial T2W Images (1A and B)

Figure 2(A-H)

Diffusion weighted images reveal restricted diffusion with hyperintense signal involving bilateral para-sagittal parietal regions, body and splenium of corpus callosum, external capsules, thalami and cerebellar peduncles (2A D). Corresponding ADC images show corresponding decreased signal in the above mentioned lesions (2E-2H)

Figure 3(A-D)

MRI done after 1 week, diffusion weighted images reveal progressive restricted diffusion with hyperintense signal (arrows) involving parietal-temporal cortex and subcortical white matter, body and splenium of corpus callosum, external capsules, thalami and cerebellar peduncles. (3A-3D)