This appeared only once, in Question 24.5 from the first paper of 2009. As such, it is a of little importance. However, while looking to expand on the college answer, I was disturbed to find that nowhere is there a list of differentials for this.
Thus, for completeness, here is one such list, within a familiar VINDICATE template.
Vascular:
Infectious:
Neoplastic:
Drug-related:
Idiopathic/inflammatory:
Autoimmune:
Traumatic
Endocrine:
Oh's Intensive Care manual: Chapter 49 (pp. 549) Disorders of consciousness by Balasubramanian Venkatesh
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