Also known as leukocytes, they are produced in the bone marrow and they take the lead in the organism’s defense mechanism against infection.
Increased values of white blood cells
- Smoking
- Physical or emotional stress
- Drugs (cortisone, lithium, non-steroidal anti-inflammatory drugs)
- Infection or inflammation
- Hematological malignancies
Decreased values of white blood cells
- Infection
- Chemotherapy
- Immune deficiency
- Hepatic cirrhosis
- Malnutrition
- Hypersplenism
- B12 and folate deficiency
They are classified in 3 groups:
Granulocytes
They are named after the granules they contain. They are also called polymorphonuclears due to their multilobular nucleus. There are three types of granulocytes:
i). Neutrophils: They represent the majority of white blood cells. They are the first cells to arrive in the area of inflammation to fight pathogens.
Increased values of neutrophils
- Infection
- Trauma
- Hemorrhage
- Septicemia
- Chronic myelogenous leukemia
- Rheumatoid arthritis
- Ulcerative colitis
- Diabetic ketoacidosis
- Smoking
- Pregnancy
- Obesity
Decreased values of neutrophils
- Myelodysplastic syndrome
- Aplastic anemia
- Chemotherapy
- Autoimmune diseases
- Drugs (penicillin, phenytoin)
ii). Eosinophils: They play an integral part in allergic reactions and parasitic infections.
Increased values of eosinophils
- Allergy
- Parasitic infections
- Scleroderma
- Pernicious anemia
- Chronic myelogenous leukemia
- Systematic lupus erythematosus
- Ulcerative colitis
Decreased values of eosinophils
- Infections
- Cushing’s syndrome
iii). Basophils: They account for a small percentage of the total white blood cell number and they participate in the inflammatory process by increasing the blood flow in the affected area with the release of histamine, bradykinin and serotonin. Moreover, their granules secrete the natural anticoagulating substance, heparin.
Increased values of basophils
- Chronic myelogenous leukemia
- Chronic sinusitis
- Splenectomy
- Myxedema
- Small pox
- Measles
- Chicken pox
- Ελκώδης κολίτιδα
Decreased values of basophils
- Graves’ disease
- Infections
- Pregnancy
2. Lymphocytes
They are immune cells (which include the T-lymphocytes and the B-lymphocytes), produced in the bone marrow and released in the circulation and central lymphoid organs and tissues such as the lymph nodes, the spleen and the tonsils.
Increased values of lymphocytes
- Chronic leukocytic leukemia
- Crohn’s disease
- Addison’s disease
- Toxoplasmosis
- Viral diseases (rubella, mumps, hepatitis, chicken pox)
Decreased values of lymphocytes
- Aplastic anemia
- Hodgkin’s lymphoma
- AIDS (Acquired immune deficiency syndrome)
- Systemic lupus erythematosus
- Myasthenia Gravis
3. Monocytes
Monocytes comprise the second biggest cellular population of the immune system. They are also produced in the bone marrow and reside in blood and tissues where they differentiate into macrophages.
Increased values of monocytes
- Myeloproliferative disorders
- Hodgkin’s lymphoma
- Brucellosis
- Multiple myeloma
- Chronic inflammatory disorders
- Subacute bacterial endocarditis
- Tuberculosis
Decreased values of monocytes
- Aplastic anemia
- Chemotherapy
- Hairy cell leukemia
- Κορτικοστεροειδή
- monoMAC syndrome
Additional information
Inverse neutrophils/lymphocytes ratio: It represents an inversion of the neutrophils/lymphocytes normal percentage ratio.
Right shift of WBC: Neutrophils have an increased number of lobes at their nucleus. It is encounterd in hepatic disease, megaloblastic anemia and Down’s syndrome.
Left shift of WBC: The increased number of immature neutrophils. It is typical after bone marrow recovery from suppression as well as in serious infection, where the organism’s need for neutrophils exceeds the bone marrow’s ability to release them in blood circulation.