title: Neuropsychiatric manifestations of vitamin B12 deficiency in the absence of anemia or macrocytosis: a case report.
abstract: We describe an atypical case of a young adult who had the acute onset of neuropsychiatric symptoms consistent with vitamin B12 deficiency despite a normal hematocrit, a normal MCV, a normal peripheral blood smear, a normal bone marrow biopsy, a normal Schilling test but abnormally low serum vitamin B12 levels. The patient responded quickly to parenteral vitamin B12 therapy but had mild residual symptoms at the time of his last clinic visit.
authors.affiliation: Department of Medicine, USD School of Medicine.
authors.forename: H
authors.initials: H
authors.lastname: Shanoudy
authors.forename: A G
authors.initials: AG
authors.lastname: Salem
mesh_terms: D000328:Adult; D000748:Anemia, Macrocytic / Q000175:diagnosis / Q000523:psychology; D003937:Diagnosis, Differential; D006801:Humans; D008297:Male; D019965:Neurocognitive Disorders / Q000175:diagnosis* / Q000523:psychology; D009460:Neurologic Examination; D009483:Neuropsychological Tests; D014806:Vitamin B 12 Deficiency / Q000175:diagnosis* / Q000523:psychology