A normal white blood cell count for both men and women is 4,500 to 10,000 cells per microliter, according to MedlinePlus. Anything over this range is considered high, including a count of 11,000. A high white blood cell count is referred to as leukocytosis and does not always signal illness.
Slightly high WBC results can be caused by medications such as lithium, heparin, epinephrine, corticosteroids and beta adrenergic agonists, according to MedlinePlus. People who have had their spleen removed or who smoke cigarettes may also have slightly high WBC results. Medical conditions that cause leukocytosis include anemia, bacterial infection, tissue damage, leukemia and inflammatory disease such as rheumatoid arthritis.