Causes of White Blood Cell Disorders based on TCM
Etiology and Pathogenesis: In traditional Chinese medicine, it's beleived that blood cell disorders has a close relation to the heart, liver, spleen and kidney. And it's particularly close relations to spleen and kidney. The primary cause of the disease is the deficiency of spleen and kidney. In addition, toxic heat invasion and stagnant blood coagulation can be important reasons for blood cell disorders.

In TCM spleen is considered to be the foundation of acquired constitution. It's the source of qi and blood. It is the spleen that nourishes the Zang-Fu organs. If the spleen is too weak to produce Qi and blood, then there is the syndrome of blood deficiency. Further, the kidney is the origin of congenital constitution. It is kidney that contols the bone, produces bone marrow and the vital essence. If the kidney is not strong enough to produce vital essence, then there would come to the syndrome of blood deficiency as well. So, it's very important to improve the function of spleen and kidney when treating blood cell disorders in traditional Chinese medicine.

Besides, in TCM it is believed that heat toxins, radiotherapy, and chemotherapy can lead to blood cell disorders. When heat toxins invades the human body, nutrient qi and yin fluid will be damaged.
 
Causes of White Blood Cell Disorders in western medicine
Blood cell disorders may be caused by disease or they may be inherited from your parents (hereditary). For example, an iron deficiency due a lack of iron in the diet or problems with absorbing iron can result in your body not being able to produce enough red blood cells, while a genetic condition, such as polycythemia vera, can cause it to produce too many. If you have an autoimmune disease, such as lupus, your immune system may destroy your own blood platelets. This will hamper your body’s ability to stop episodes of bleeding. Low or compromised white blood cells are caused by infections that destroy or overwhelm them. Some health conditions destroy white blood cells faster than the bone marrow can produce them. Your body may also increase its production of white blood cells to fight a disease or infection.

Leukocytosis
Diseases that cause leukocytosis include leukemia and acute infections. Leukemia increases the number of white blood cells tremendously. A normal white blood cell count is below 11,000. Counts of more than 100,000 are possible with leukemia. Another cause of leukocytosis is bacterial or parasitic infection. When the body is fighting these infections, it will increase the number of white blood cells. This increase may overcome the infection. When it does not, antibiotics or other drugs can help the body defeat the infection. When the infection is over, the white blood cell count will probably decrease.

Neutropenia
Some diseases can destroy white blood cells or damage the body’s ability to make them. Leukemia, which increases the overall number of white blood cells, actually decreases the number of healthy white blood cells. HIV/AIDS destroys white blood cells. Some parasites also attack white blood cells. Chemotherapy, which is used to treat cancer and other diseases, can destroy white blood cells. As a result, a child being treated with chemotherapy is also at risk for developing serious infections.