Is hypothalamic involvement truly a red flag for multiple sclerosis?

Any hypothalamic disturbance manifesting clinically is considered a major red flag for multiple sclerosis, whereas MRI lesions involving deep grey matter structures are considered an intermediate red flag. However, hypothalamic lesions manifesting clinically with hypersomnia have been described in some patients of multiple sclerosis. We report a case where the first and presenting feature of multiple sclerosis was acute onset hypersomnia with bilateral hypothalamic lesions. On review of recent literature, we also question whether clinical or radiological hypothalamic involvement is really so unusual that it should be considered a red flag for multiple sclerosis