What is the reason for low white blood cell count?

Low white blood cell count means leukopenia. Many children will be found to have low white blood cell count through blood tests after they have a fever. This is a common cold caused by viral infection. There are many other reasons for low white blood cell count, including chemical factors, immune factors and so on.

1. Bone marrow damage:

1. Damage caused by drugs: Anti-tumor drugs and immunosuppressants can directly kill proliferating cell groups. Drugs inhibit or interfere with granulocyte nucleic acid synthesis, affect cell metabolism, and hinder cell division. Direct toxic effects of drugs causing granulocytopenia are related to drug dose. Many other types of drugs may also have direct cytotoxicity or reduce granulocyte production through immune mechanisms.

2. Chemical poisons and radiation: Chemicals such as benzene and its derivatives, dinitrophenol, and arsenic are toxic to hematopoietic stem cells. X-rays and neutrons can directly damage hematopoietic stem cells and the bone marrow microenvironment, causing acute or chronic radiation damage and granulocytopenia.

3. Immune factors: Autoimmune granulocytopenia is caused by the action of autoantibodies, T lymphocytes or natural killer cells on different stages of granulocyte differentiation, leading to bone marrow damage and granulocyte production disorders. Common in rheumatic and autoimmune diseases.

4. Systemic infection: bacterial infection such as mycobacterium (especially Mycobacterium tuberculosis) and viral infection such as hepatitis virus.

5. Abnormal cells infiltrate the bone marrow: cancer bone marrow metastasis, hematopoietic malignancies and myelofibrosis cause the failure of bone marrow hematopoietic function.

6. Cell maturation disorder - ineffective hematopoiesis: such as folic acid and vitamin B12 deficiency, which affects DNA synthesis, active bone marrow hematopoiesis, but cell maturation stagnates and is destroyed in the bone marrow. Certain congenital agranulocytosis and acute non-lymphocytic leukemia, myelodysplastic syndrome, and paroxysmal nocturnal hemoglobinuria also have maturation disorders, leading to granulocytopenia.

(ii) Abnormal distribution of peripheral circulating granulocytes.

(III) The demand for granulocytes in extravascular tissues increases and their consumption accelerates.

(iv) Mixed factors.

Such as chronic idiopathic neutropenia, cyclic neutropenia, etc. In clinical practice, the above three types of leukocytopenia often exist in combination and require careful analysis.