Neutrophil

The neutrophil, AKA polymorphonucleocyte or PMN is a white blood cell. It is often seen in the context of acute inflammation.

Histology

• Little dots = the multilobular nucleus - key feature.
• Neutrophils are often found with friends, i.e. lymphocytes, plasma cells.

DDx of little dots:

• Nuclear debris - apoptotic cell.
  • Apoptotic cell -- has nuclear condensation (pyknosis), eosinophilic cytoplasm.

Notes:

• You find PMNs by their nucleus; on a histologic section don't bother looking for the cell membrane (they are usually impossible to see).
• A collection of PMNs... think about necrosis and abscess.

Pathology

Hypersegmentation = megaloblastic anemia.

See also

• Basics.
• Dysgranulopoiesis.
• Red blood cell.
• Chronic granulomatous disease - caused by neutrophil dysfunction.
• Eosinophil.