OVERVIEW
白细胞减少症一般指外周血中白细胞计数持续低于健康人正常值的状态
轻者无症状，严重者可表现为疲乏、无力、头晕、食欲减退、易感染等
主要与感染、药物、理化因素、疾病等因素有关
以去除病因，预防感染治疗为主，部分需升白细胞治疗
Definition.
Leukopenia is generally defined as a state in which the white blood cell count in the peripheral blood is consistently below the normal value for a healthy person. It is usually less than 4.0 x 109/L in adults, less than 4.5 x 109/L in children 10 to 12 years of age, and less than 5.0 x 109/L in children <10 years of age.
Decrease in total leukocyte count is mainly influenced by the number of neutrophils, and large changes in the number of lymphocytes can also cause changes in the total leukocyte count.
Neutropenia is defined as an absolute neutrophil count of less than 2.0 × 109/L in adults, less than 1.8 × 109/L in children >10 years of age, or less than 1.5 × 109/L in children <10 years of age; an absolute neutrophil count of less than 0.5 × 109/L is referred to as granulocyte deficiency.
Causes
Causes
Congenital
Primary or hereditary disorders such as chronic primary neutropenia, chronic familial neutropenia, and, less commonly, periodic neutropenia.
Acquired
生成减少
Bone marrow injury: chemical poisons, ionizing radiation, cytotoxic drugs, etc. directly damage or inhibit hematopoietic stem cells.
Bone marrow infiltration: myeloma, leukemia, metastatic tumors infiltrate the bone marrow and affect normal hematopoiesis.
Maturation disorders: nutrient deficiencies such as vitamin B12 or folic acid, myelodysplastic syndromes, paroxysmal sleep hemoglobinuria, etc. affect the normal maturation of leukocytes.
Infection: viral, bacterial infection, etc.
消耗或破坏过多
Immune factors: including drugs, autoimmune diseases such as systemic lupus erythematosus, rheumatoid arthritis, etc. can cause leukopenia.
Non-immune factors: including increased leukocyte depletion caused by severe infections, or hypersplenism leading to neutrophil retention and destruction in the spleen.
分布异常
Hemodialysis can cause leukocytes to remain in the pulmonary vasculature for a short period of time. Severe bacterial infections and malignant malnutrition can cause leukocytes to shift to the limbic pool and cause pseudogranulocytopenia.
Symptoms
Main Symptoms
Symptoms of leukopenia vary according to the severity and primary disease.
轻度（中性粒细胞＞1.0×109/L）
Clinically, there are generally no specific symptoms, mainly manifested as symptoms of the primary disease.
中度[中性粒细胞（0.5～1.0）×l09/L]及重度（中性粒细胞＜0.5×109/L）
In addition to the symptoms of the primary disease, non-specific symptoms such as fatigue, weakness, dizziness and loss of appetite can also be seen.
Susceptible to infection, respiratory, gastrointestinal and urinary tract infections may occur. Those with granulocyte deficiency may have high fever, infectious toxic shock and other symptoms.
Consultation
Department of Medicine
Hematology
If you notice persistent leukopenia, it is recommended that you consult a hematologist.
Preparation
Preparation for Consultation: Registration, Preparation of Documents, Frequently Asked Questions
Tips for Consultation
Before seeking medical treatment, you should take proper protection, including wearing a mask and sterilizing the body diligently to avoid infection.
Preparation Checklist
症状清单
Pay particular attention to the time of onset of symptoms, special manifestations, etc.
Are there any symptoms such as easy fatigue, fatigue, dizziness, loss of appetite, etc.?
Are there symptoms of recurrent fever?
Are there symptoms such as coughing, coughing up pus and sputum, pus and blood stools, frequent urination, urinary urgency, painful urination, hematuria, etc.? Are they frequently recurring?
病史清单
Are there any blood diseases, acute or chronic infections, or rheumatic diseases?
Are there any blood diseases, acute or chronic infections, or rheumatic diseases among relatives?
Are there any relatives with leukopenia or neutropenia?
Is the patient taking medication for a long period of time?
Has there been recent chemotherapy?
Has there been recent radiation therapy?
Have you had any recent X-rays or computed tomography (CT) scans?
Have been exposed to pesticides or other toxic substances?
检查清单
Test results from the last 6 months to bring to the doctor’s office
Report cards for routine blood, urine, stool, and biochemical tests.
Bone marrow cytology report card.
用药清单
Medication for the past 3 months, if available in boxes or packages, bring along to the doctor’s office.
Cytotoxic antitumor drugs such as antimetabolites and alkylating agents.
Antipyretic and analgesic drugs such as ibuprofen, aminopyrine, indomethacin, etc.
Antibiotics such as penicillin, chloramphenicol, sulfonamides, etc.
Anti-tuberculosis drugs such as isoniazid, para-aminosalicylic acid, ethambutol, etc.
Anti-malarial drugs such as chloroquine, primaquine, etc.
Antithyroid drugs such as methylthiouracil, methimazole, etc.
Hypoglycemic drugs such as Toluenesulfonylurea, Chlorosulfopropylurea, etc.
Antihypertensive drugs such as captopril, methyldopa, etc.
Immunomodulatory drugs such as azathioprine, levamisole, mertiomacrophenol, etc.
Antipsychotic drugs such as chlorpromazine, tricyclic antidepressants, etc.
Other drugs.
Diagnosis
Diagnosis is based on
Medical history
Recent history of anti-infective drug administration, infection, radiation exposure, toxic exposure, or history of rheumatoid immune disease, tumor, hematological disease, or acute or chronic infection, etc., or family history of leukopenia.
Clinical manifestations
症状
Easy fatigue, fatigue, dizziness, loss of appetite and other non-specific symptoms.
May be combined with infections of the lungs, urinary tract, digestive tract and other parts of the body.
Laboratory Tests
血常规
The number of various types of blood cells in the peripheral blood can be evaluated to determine initially whether there is a decrease in leukocytes and what type of cellular decrease is responsible for the decrease in leukocytes.
A white blood cell count in the peripheral blood of adults is consistently below 4.0 x 109/L, while the diagnostic criteria for children aged 10 to 12 years is below 4.5 x 109/L and for children <10 years is below 5.0 x 109/L.
Fasting is not required before the test, and venous blood is usually used for the test; it is recommended that in addition to the routine blood test, a manual classification count of peripheral blood smears should be performed at the same time.
Fixed time: different time of the day, season, sports, physical activities can affect the white blood cell count. It is necessary to fix the time, try to eliminate the influencing factors, and perform multiple tests to make a comprehensive judgment.
骨髓细胞学检查
Bone marrow image can assess the hematopoietic condition of bone marrow, identify the cause of the disease and determine the severity of the disease.
Different causes of the disease may have different bone marrow images, which may show normal hematopoietic tissue or mild hyperplasia, hypoproliferative bone marrow, and so on.
If necessary, immunophenotyping of bone marrow cells, chromosomal and fusion gene or gene mutation tests are performed to clarify whether the leukopenia is caused by myelodysplastic syndromes, hypoproliferative leukemia and other hematologic malignancies.
中性粒细胞特异性抗体测定
Determine the presence of antigranulocyte autoantibodies and identify the etiology.
Includes: leukocyte aggregation reaction, immunofluorescence granulocyte antibody assay.
Positive antibodies suggest that leukopenia is related to immune factors.
肾上腺素试验
Epinephrine is measured to rule out pseudogranulocytopenia.
Treatment
Aim of treatment: to remove the cause of the disease and to prevent infection.
Treatment principle: Generally, identify the cause of the disease, treat the primary disease and prevent infection. For severe leukopenia, consider leukocyte-boosting therapy.
General treatment
Treat the cause of the disease and stop exposure to drugs or other factors that may cause the disease. Leukocytes generally recover when the primary disease is resolved or controlled.
People with mild leukopenia generally do not need special precautions. People with moderate to severe leukopenia are susceptible to infection and need to pay attention to personal protection, avoid gathering in crowded places and maintain personal hygiene.
People with severe leukopenia need to stay in a sterile laminar flow ward or a sterile laminar flow bed if necessary.
Medication
Granulocyte colony-stimulating factor (G-CSF)
Improve neutropenia and accelerate the recovery of granulocyte count.
Medication precautions: blood monitoring is required 2 times a week while using it.
Adverse reactions include fever, musculoskeletal aches and pains, and rash. A few may have allergic reactions.
Granulocyte-Macrophage Colony Stimulating Factor (GM-CSF)
May stimulate the maturation and release of granulocytes and monocyte macrophages.
Precautions for the use of the drug: need to be started 24 to 48 hours after the end of the administration of chemotherapeutic drugs, the use of the need to monitor the blood 2 times a week; pregnant women, hypertension and a history of epilepsy should be used with caution.
Adverse reactions include fever, chills, nausea, dyspnea, diarrhea, rash and chest pain.
Other drugs to promote granulocyte production
B vitamins (vitamin B4, B6), shark liver alcohol, lisinopril and so on.
Role of drugs: may assist in improving leukopenia.
Anti-infective drugs
Including: broad-spectrum antibiotics, antifungal drugs, antiviral drugs, etc.
Before the causative organisms have been clarified, broad-spectrum antibiotic treatment covering Gram-negative and Gram-positive bacteria can be applied empirically, and the medication can be adjusted after the results of pathogen and drug sensitivity are available.
If 3 to 5 days are ineffective, antifungal medication may be added. Antiviral drugs may be added for viral infections.
Immunosuppressants
Glucocorticosteroids such as methylprednisolone, azathioprine, cyclophosphamide and so on.
Action of the drug: mainly against granulocytopenia caused by immune mechanism.
Adverse effects: Cushing’s syndrome, withdrawal reaction, inducing and aggravating peptic ulcer, etc.
Surgical treatment
Splenectomy can be considered for granulocytopenia caused by splenomegaly, but the pros and cons of splenectomy should be considered comprehensively before splenectomy.
Prognosis
Cure
Mild and moderate leukopenia will return to normal after the primary disease is cured or effectively controlled.
Those with granulocyte deficiency have a higher mortality rate.
Prognostic factors
Correlates with the degree and duration of neutropenia, progression of the disease, primary etiology, and treatment measures during infection.
Daily
Daily management
Dietary management
Diet is based on a high protein, high fiber diet with balanced nutrition.
Avoid eating cold and unclean food.
Life Management
Maintain a regular routine and ensure sufficient sleep.
People with severely low white blood cells need to standardize the wearing of masks and reduce access to public places.
Disease monitoring
Regular blood tests to monitor the number of white blood cells and neutrophils.
Follow-up
Follow the doctor’s instructions for regular blood tests and other tests.
If fever or infection occurs, it is recommended to consult the doctor promptly.
Prevention
Keep away from ionizing radiation and chemical poisons such as benzene and trinitrotoluene.
People who are exposed to radiation or benzene for a long period of time at work need to be well protected and have their blood tests checked regularly.
Those who need to use high-risk drugs such as anti-tuberculosis drugs and anti-tumor drugs for a long period of time should follow the doctor’s instructions and have regular blood tests.
Actively treat primary diseases such as blood system diseases and autoimmune diseases.
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