SHM Converge Scientific Abstract ePoster Gallery-The Missing Link? A Case of Myocardial Infarction and Pulmonary Embolism in a Patient With Vitamin B12 Deficiency

Pdf Summary

This case report describes a 49-year-old vegetarian man, despite taking vitamin B12 supplements, who presented with 8 months of progressive neurologic decline including paresthesias, gait instability, sensory ataxia, memory impairment, and inability to ambulate. He also had a recent myocardial infarction and was found during evaluation to have an incidental acute non-occlusive pulmonary embolism.<br /><br />Workup showed severe vitamin B12 deficiency (150 pg/mL), markedly elevated methylmalonic acid, and severe hyperhomocysteinemia. MRI/MRA findings were consistent with subacute combined degeneration of the spinal cord, explaining his neurologic symptoms. Anti–intrinsic factor antibodies were positive, indicating pernicious anemia as the likely cause of his deficiency despite his vegetarian diet and supplementation.<br /><br />The patient was treated with intramuscular cyanocobalamin and therapeutic anticoagulation with apixaban. He improved rapidly, reporting better sensation, memory, and cognition after the first B12 injection, and gradually regained mobility with a rolling walker before discharge to acute rehabilitation.<br /><br />The report emphasizes that vitamin B12 deficiency is usually recognized for neurologic manifestations, but it can also cause elevated homocysteine, which is associated with arterial thrombosis, venous thromboembolism, coronary artery disease, and increased mortality. This case highlights the need for clinicians to consider pernicious anemia even in patients who report adequate dietary intake or supplementation, and to recognize vitamin B12 deficiency as a potential contributor to both neurologic and thrombotic events.

Asset Subtitle

F. Jeffrey Lorenz

Meta Tag

Author List Anna Ptasinski, F. Jeffrey Lorenz, Scott Weismiller, Sheila Nguyen

Category Clinical Vignettes

Concept Vitamin B12 Deficiency

Concept Subacute Combined Degeneration

Concept Pernicious Anemia

Concept Methylmalonic Acid

Concept Homocysteine

Distinguished Non-Finalist

Presenter Organization Penn State College of Medicine

Presenting Author F. Jeffrey Lorenz

Track Adult

Keywords

vitamin B12 deficiency

pernicious anemia

subacute combined degeneration

hyperhomocysteinemia

methylmalonic acid

neurologic decline

pulmonary embolism

myocardial infarction

intrinsic factor antibodies

cyanocobalamin

Vitamin B12 Deficiency

Subacute Combined Degeneration

Pernicious Anemia

Methylmalonic Acid

Homocysteine