A nutritional Vitamin B12 deficiency (infantile tremor syndrome) presenting as hemiconvulsion hemiplegia epilepsy syndrome

Abstract

Hemiplegia Hemiconvulsion Epilepsy syndrome (HHE syndrome) is a condition characterized by the acute onset of unilateral seizures, which progress to cortical atrophy, hemiplegia and later develop epilepsy over weeks to years. Various aetiologies include infectious causes, especially meningitis, encephalitis, trauma, vascular insults, and sometimes idiopathic. Here, we present a 13-month-old female child, first in birth order, born to a non-consanguineous marriage, who presented with mild global developmental delay with acute onset right focal seizures followed by right-sided weakness and drug-resistant epilepsy. The child was found to have clinical and biochemical features of vitamin B12 deficiency with right-sided weakness. MRI of the brain initially showed edema of the left cerebral hemisphere and later atrophy on the left side. The electroencephalogram showed low voltage activity over the left cerebral hemisphere. Post-treatment with cobalamin, improvement in development was noted, with partial improvement in weakness and persistent epilepsy. In the current report, we highlight Hemiplegia Hemiconvulsion Epilepsy (HHE) syndrome on the background of nutritional vitamin B12 deficiency.