Diagnosing vitamin B12 deficiency, a common geriatric disorder.

Vitamin B12 deficiency in the elderly is a common disorder associated with an increased morbidity if it goes undetected, as often happens. Its diagnosis can be enhanced if the clinician recognizes the associated clinical features of nonspecific symptoms, glossitis, and dermatologic and neuropsychiatric abnormalities, and realizes the limitations of various tests (serum B12 assay, parietal cell and intrinsic factor antibody, mean corpuscular volume, and Schilling tests). Available data indicate it is sufficient to prescribe replacement B12 injections three or four times a year.