Blood in the human body contains many types of cells. White blood cells or WBC is one of the types that are responsible for the body’s immune system. These cells are made inside the bone marrow. The WBC count is an important measurement to decide on various health conditions. Low count of white blood cells, also known as leukopenia, keeps people at a risk of infection. This condition can be diagnosed with a complete blood test. Certain medications can increase or even decrease the number of WBC in blood.

Causes of low white blood cell count
The WBC count, also known as leukocyte, is measured in terms of the number of cells per volume of blood. There is no particular number which can be defined as a normal count of WBC, but 4,500-10,000 WBCs per cubic millimeter can be considered as the normal range. The causes for low blood platelet counts are as follows:

• Bone marrow – Congenital disorders can cause low functioning of bone marrow in individuals.
• Radiation therapy – Used to treat cancer, radiation therapy damages healthy WBC along with cancer cells. One of the causes of low white blood cell count is when this cancer treating therapy destroys stem cells in the bone marrow.
• Chemotherapy – Most of the chemotherapy medications destroy cells in the bone marrow, which is responsible for producing WBC. Though the cell count improves with time, doctors may suggest alternate chemotherapy medicines if the patient is at a high risk of WBC counts.
• Leukemia – This cancer grows in the bone marrow and affects lymph and blood-forming tissues in the body. This, in turn, restricts the production of WBCs.
• HIV/AIDS – One of the causes of low white blood cell count is HIV, a virus that disrupts the body’s capability to fight organisms that cause infections.
• Aplastic anemia – This is a medical condition which arises when the body ceases to produce sufficient new WBC, thus causing a low WBC count and leaving the body prone to infections.
• Viral infections – Infections in the body cause disruption in the functioning of the bone marrow, thereby contributing to causes of low white blood cell count. There are severe infections too which use WBC more than they are produced.
• Medications – Several antibiotics that are prescribed to fight infections can also destroy white blood cells in the body.

Low WBC can be treated by a blood transfusion from a person with high WBC count to a person having low WBC. Also, doctors may prescribe medications which can stimulate the production of WBC in the body.