Does having a high white blood cell count indicate leukemia?

Not necessarily: White blood counts can be elevated as a result of an infection or inflammatory process. When this happens it is called a leukemoid reaction and is a normal physiologic response.

Not necessarily: It should always be of concern and should lead to a more complete blood work, especially to see what your red blood cell count and platelet count is. If those are normal, it is unlikely leukemia. The WBC count should be rechecked two weeks later. If red blood cells or platelets are clearly abnormal, you should see a doctor immediately.

Not necessarily: While leukemia can be associated with high white cell count, infections are more commonly associated with high white cell count.

Not necessarily: There are many possible causes of a high white blood cell count including infection, allergic reactions, medication effects, other types of "inflammation", and also leukemias.