Vitamin B12 Deficiency Related Syncope in a Young Military Pilot.

Syncope and near-syncope are commonly encountered symptoms. Many cases are situationally specific or otherwise benign, with no adverse aeromedical implications. Autonomic dysfunction can produce orthostatic intolerance with resultant symptoms and is aeromedically concerning for potential occurrence in flight. Vitamin B12 deficiency is an insidious condition with protean manifestations, which can present with autonomic dysfunction. Neurological abnormalities are often reversible following adequate replacement. We describe a case of vitamin B12 deficiency in a pilot with atypical syncope and abnormal tilt-table testing who had progressively abnormal hematologic findings on review. He was also discovered to have intrinsic factor antibodies. After B12 replacement, he had normal cardiovascular response to exercise stress testing and an unremarkable centrifuge assessment. This case highlights the importance of recognizing subtle laboratory findings and serial laboratory data review in cases of atypical syncope to identify potential reversible etiologies.