1.Basic knowledge of white blood cells
Leukocytes are colorless cells in the blood and tissues of humans and animals. They are a class of nucleated blood cells that are capable of deformational movements. Leukocytes generally have the ability to move actively, and they can migrate from intravascular to extravascular or from extravascular tissues to intravascular. Therefore, leukocytes are widely found in tissues other than blood vessels and lymphatic vessels, in addition to blood and lymphatic vessels.
Leukocytes can engulf foreign substances to produce antibodies and play an important role in the healing of body damage, resistance to invasion of pathogens and immunity to disease. The normal human leukocyte count is 4000-10000/UL (microliter).
2.Definition of leukopenia
Leukopenia (leukocytopenia) is a common blood disorder. If the total number of leukocytes is significantly reduced to less than 2×109/L and the absolute value of neutrophils is less than 0.5×109/L, or even disappears, it is called agranulocyte deficiency (agranulocysis).
3.What are the discomforts of leukopenia?
The symptoms are mild, mainly weakness, dizziness, easy to catch a cold, often accompanied by low fever, pharyngitis, loss of appetite, limb weakness, insomnia, palpitations, chills, etc. If the granulocyte deficiency is acute, sudden chills or chills, high fever, headache, arthralgia, extreme weakness, severe swallowing difficulties, delirium or coma, and death within a few days. .
4.Causes of leukopenia
Infection, cytotoxic drugs, ionizing radiation, chemical toxins are common causes of leukopenia, classified by the process of initiation: impaired proliferation and maturation of granulocytes (generation reduction type); excessive destruction and loss of granulocytes (immune type) and abnormal distribution of granulocytes.
5.What tests should be done to detect leukopenia?
(1) Blood picture: Red blood cell and platelet counts are mostly normal. Some malignant tumors infiltrating the bone marrow may be accompanied by anemia and thrombocytopenia, and the white blood cell count is <4×109/L. The absolute value of neutrophils is <0.5×109/L in the case of granulocyte deficiency. Neutrophils often have degeneration such as toxic granular vacuoles in the cytoplasm. Atypical lymphocytes and abnormal cells should be noted in severe infections where leftward nuclear shift or infantile cells are seen.
(2) Bone marrow picture: It varies according to the cause of the disease. There may be no obvious changes in the early stage, or there may be a “maturation disorder” with many young granulocytes and fewer mature granulocytes, or there may be a gradual appearance of granulocytes in all stages during the recovery phase of the disease.
(3) Bone marrow biopsy: It has important value for bone marrow fibrosis, bone marrow metastasis, lymphoma, etc. Bone marrow examination can help the differential diagnosis of MDS.
(4) Bone marrow culture: in vitro CFU-GM colony culture can understand myeloproliferative active bone marrow, neutrophil reserve to help identify the direct toxic effects of drugs, or immune factors inhibit granulocyte production.
(5) Epinephrine test helps to identify pseudogranulocytopenia.
(6) Anti-neutrophil antibody assay to help identify immune granulocytopenia.
(7) Antinuclear antibody (ANA) rheumatoid factor (RF) titer assay immunoglobulin assay.
(8) serum lysozyme assay elevated lysozyme, suggesting granulocytopenia or lack of granulocytes is due to excessive destruction of lysozyme normal or decreased granulocyte production reduction.
6, the prevention and control measures of leukopenia
Avoid going to public places as much as possible to prevent respiratory infections. Avoid taking drugs that cause bone marrow damage or leukopenia. Avoid cold and unclean food to avoid digestive system infection. For workers exposed to radiation, pay attention to safety precautions, check blood picture regularly, and transfer immediately if leukopenia is detected. Avoid contact with chemicals and radioactive substances that cause bone marrow damage.
For staff exposed to toxic chemicals such as benzene and xylene, check the blood picture regularly. Diet should be light and nutritious, avoid fatty, sweet and greasy to prevent wetness from trapping the spleen. During the infection period of acute granulocyte deficiency, avoid spicy, mutton, shrimp, crab and other hairy substances.
Chemicals and drugs that have an effect on leukocytes
Production toxins that have an effect on leukocytes are more common, including benzene, dinitrophenol, di-2-3, thioglycolic acid, petroleum products, trinitrotoluene, and butylene dioxide can cause granulocytopenia. Acute oxadiene poisoning and chronic poisoning with already diols and tetrachlorobenzene can cause lymphocytosis. Chronic phosphorus poisoning and exposure to tetrabromoethane can have mononucleosis. Amyl acetate can cause acid granulocytosis.