🔬 Peripheral blood smear. In the center of the field of view: a neutrophil with nuclear hypersegmentation.
📊 Criteria for hypersegmentation (according to ICSH): Hypersegmentation is defined as the appearance of neutrophils in any quantity with more than 5 nuclear segments or more than 3% of neutrophils having 5 segments (when examining 100 neutrophils).
❗Thus, even 1 neutrophil with 6 segments can be considered significant.
🧪 What to do upon detection? If hypersegmented neutrophils are found: 📍 Check MCV (mean corpuscular volume) — macrocytosis often accompanies hypersegmentation. 🧪 Order tests for B12, folate, homocysteine, methylmalonic acid. 🔁 Repeat the smear in dynamics — to exclude a transient effect. 🧬 If there is dysplasia of other hematopoietic cell lines — consider MDS and refer for a myelogram.
🙏 Image kindly provided by Irina Neklyudova Head of Clinical Diagnostic Laboratory, MC Academia, Ulyanovsk
