Leukocytosis refers to an increase in the number of white blood cells (leukocytes). It is a common reaction to a variety of inflammatory states.
(A) Heavy, perivascular and interstitial neutrophilic infiltration (arrowhead) are present (H&E stain, ×40). (B) Fibrinoid necrosis of the small blood vessels with fibrin extravasation and leukocytosis forming nuclear dust (arrowhead) are visible on skin biopsy (H&E stain, ×200). Pulmonary Leukocytoclastic Vasculitis as an Initial Presentation of Myelodysplastic Syndrome: Tuberculosis and Respiratory Diseases. Not altered. CC.
| Newborn infant | > 38,000 per mm3 (13.0 to 38.0 × 109 per L) |
| Infant two weeks of age | > 20,000 per mm3 (5.0 to 20.0 × 109 per L) |
| Adult | > 11,000 per mm3 (4.5 to 11.0 × 109 per L) |
| Pregnant female (third trimester) | > 13,200 per mm3 (5.8 to 13.2 × 109 per L) |
