The peripheral blood leukocyte count is considered below normal when it is consistently lower than 4.0×109/L, which is called leukopenia. There are many causes of leukopenia, which can be broadly classified into the following three categories according to the etiology and pathogenesis: I. Decreased leukocyte production Leukocytes are a type of human blood cell. Certain diseases affecting human hematopoietic stem cells, such as aplastic anemia, myelodysplastic syndrome Certain diseases affecting human blood stem cells, such as aplastic anemia, myelodysplastic syndrome, myeloma and other neoplastic diseases can affect the production and maturation of leukocytes, resulting in a decrease in leukocytes. In addition, when the body is exposed to chemical toxins, ionizing radiation and certain drugs can also damage the hematopoietic environment of the body, thereby inhibiting leukocyte production.
Second, excessive destruction or consumption of leukocytes When the body suffers from certain viral infections or sepsis, the number of leukocytes decreases due to excessive consumption at the site of inflammation. In addition, autoimmune system diseases such as hypersplenism, certain hepatitis or systemic lupus erythematosus can also destroy leukocytes in the body, resulting in a decrease in leukocytes.
Under normal circumstances, about 50% of the body’s leukocytes are evenly distributed in the venous blood, and the other 50% are distributed in the interstitial spaces of tissues and venous sinuses. However, when the patient has endotoxemia or dialysis and other causes, the leukocytes will accumulate in the pulmonary vessels, spleen and other locations, when the total number of leukocytes in the body is normal, but the number of leukocytes we draw and test is lower than normal, also known as pseudogranulocytopenia.
As can be seen, the causes of low white blood cells are mainly the above three categories. When the white blood cell count is consistently lower than normal, you should promptly consult a doctor, improve systematic and formal examination, and actively treat the disease after a clear diagnosis.