Neutrophilic hypersegmentation as an indicator of incipient folic acid deficiency

The authors have identified a group of subjects with neutrophilic hypersegmentation who are normal or near-normal with respect to other hematologic indices (hemoglobin, mean corpuscular volume). In a high proportion of these subjects, serum folate levels are abnormally low. In this group and a non-hypersegmented-neutrophil control group there was a significant negative correlation between average numbers of neutrophilic lobes and serum folate levels. In the subjects with hypersegmented neutrophils the predominant alteration is a shift from three-lobed to five-lobed neutrophils. It is believed that neutrophilic hypersegmentation can be a valuable adjunct in documenting and/or uncovering incipient folate deficiency.