POLYS (Polymorphonuclear Cells) on Blood Test: Understanding Neutrophils

POLYS = polymorphonuclear leukocytes = neutrophils (most common type). "Poly" = multi-lobed nucleus.

Normal Ranges (Absolute Neutrophil Count - ANC)

• Adults: 1,500–8,000/µL
• Children: 1,500–10,000/µL (higher in infants)
• % of WBCs: 50–70%

Key Functions

• First responders to bacterial/fungal infection
• Phagocytosis, degranulation, NETosis (neutrophil extracellular traps)
• Acute inflammation mediators
• Short lifespan (hours in circulation, days in tissue)

Abnormal Results

Finding	Term	Common Causes
↑ ANC	Neutrophilia	Bacterial infection, inflammation, stress, steroids, smoking, myeloproliferative neoplasms
↓ ANC	Neutropenia	Chemo, radiation, autoimmune, drugs (clozapine), B12/folate deficiency, congenital, sepsis (consumption)

Clinical Context

ANC <500 = severe neutropenia (infection emergency). ANC >30,000 = leukemoid reaction (rule out CML). Always interpret with clinical picture, not in isolation.