Leukemoid reaction is defined as a reactive leukocytosis in response to infection, inflammation, or therapeutic agents such as growth factors and malignancy.

• 摘要类白血病反应常常出现于身体对感染，发炎，和药物（如生长激素）所产生血液中白血球上升的情形。只有少数恶性肿瘤有类似的情形。