Hypersegmentation
Normal neutrophilic nuclei have 3-4 segments, and few with 5 segments may be present. One speaks of hypersegmentation when there are many neutrophils with 5 segments (>3-5% of all segmented neutrophils), or when neutrophils with 6 or more segments are present.
The most common and typical cause is folic acid or vitamin B12 deficiency. In addition, infection with Helicobacter pylori or treatment with medications such as hydroxyurea and G-CSF also causes neutrophil hypersegmentation.
