Assessment of deoxyuridine suppression test in diagnosis of vitamin B12 or folate deficiency.

Deoxyuridine (dU) suppression tests have been performed on virtually all marrow samples aspirated at this hospital over the past 12 months. Of the 110 samples studied 26 gave abnormal results, and these 26 samples came from patients deficient in either vitamin B(12) or folate. The dU suppression test was found to be of particular value in the diagnosis of vitamin B(12) or folate deficiency in non-anaemic patients with macrocytosis and equivocal changes in marrow morphology and in patients in whom the serum vitamin B(12) or red cell folate levels were within the normal range.