Abstract
A 16-year-old Saudi female who is a known case of glycogen storage disease type 1A (GSD1A), presented to the emergency department at King Faisal Specialist Hospital, Riyadh, Saudi Arabia on 15th January 2021 due to a complaint of persistent vomiting. Two weeks after admission, she began developing double vision and progressive leg weakness with intact sensation. She received the primary management to maintain good hydration and was admitted to the ICU for further workup. Over her hospital course, multiple investigations were conducted, the most significant of which was the MRI after sudden ocular deterioration. The result depicted findings classic for Wernicke’s encephalopathy (WE) on MRI. The patient was then started on Thiamine supplementation and MRI performed three weeks later showed significant interval improvement of the parenchymal signal abnormality with complete resolution features of Wernicke's encephalopathy. This complex case emphasizes the need for early recognition and immediate treatment with IV thiamine in such a potential condition that can lead to permanent neurological deficits that present in a non-typical fashion.