Case Report: A New Spectroscopy Finding in Infantile Neuroaxonal Dystrophy

Abstract

Infantile neuroaxonal dystrophy (INAD) is a rare autosomal recessive disorder that is associated with developmental delay and regression. A female patient of consanguineous parents presented with gross motor delay at 15 months. She was known to have two paternal uncles who had died with a diagnosis of INAD. Over the next 15 months, she exhibited regression in several domains and following genetic testing was diagnosed with a PLA2G6 mutation in keeping with INAD. The cerebellar vermis demonstrated a significant reduction in the N-acetylaspartate/creatinine (NAA/Cr) ratio of 0.69. This case highlights what we believe to be a new imaging feature of a low NAA/Cr ratio in the cerebellar vermis with normal ratios in the cerebellar hemispheres and basal ganglia in a patient with genetically confirmed diagnosis of INAD.

Keywords

infantile neuroaxonal dystrophy - INAD - spectroscopy - cerebellar - motor delay

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