Numerical alterations in the number of leukocytes or white blood cells, whether due to a decrease or an increase, are frequent causes for consultation with the clinical hematologist. In this article Dr. Besses Raebel, a specialist in hematology, talks to us about leukopenia and leukocytosis, one of the most frequent consultations among patients who visit his office.
What is leukopenia?
Leukopenia is a decrease in the normal number of leukocytes and leukocytosis is an increase with respect to the values considered normal.
Leukopenia is a frequent consultation that worries the patient because of the possibility of an increased susceptibility to infections. In this situation, the assessment of the number of neutrophilic granulocytes, i.e. the type of leukocyte responsible for antibacterial defense, is essential. The vast majority of patients who consult for this reason have a somewhat decreased number of neutrophilic granulocytes or neutropenia, but enough not to be more susceptible to infections. In this case, the hematologist assesses the possible causes of leukopenia and neutropenia which, in general, are usually benign.
What is leukocytosis?
Leukocytosis can be the expression of an infection, drug treatment with corticosteroids, smoking or a blood tumor disease, among other causes. In the first case, the increase is due to a reaction of the organism to a bacterial infection, although sometimes an infection of viral origin can produce the opposite effect or leukopenia. Treatment with drugs or preparations containing corticosteroids may result in neutrophilic leukocytosis. In this case, identification of the drug provides the diagnosis.
Smoking can cause leukocytosis with increased neutrophilic granulocytes (neutrophilic leukocytosis) in a variable number of smokers. A relatively frequent finding is an increase in the number of leukocytes at the expense of the number of lymphocytes, the cells responsible for defense against viral infections. Lymphocytosis or increased total lymphocyte count may be seen in the course of infections with viruses such as Epstein-Barr virus (the most common in infectious mononucleosis) or other viruses, but may also be a finding indicative of a chronic blood disease that has not yet been diagnosed.
An increase in white blood cells may indicate chronic leukemia.
A persistent increase in white blood cell count may represent the first change indicative of chronic leukemia. When this possibility is suspected, the hematologist assesses the existence of lymphadenopathy (enlarged lymph nodes) or splenomegaly (enlarged spleen), the description of the appearance of the leukocytes in the microscopic review of the blood smear and the symptoms reported by the patient. Based on this basic information, an analysis of the specific characteristics of the leukocytes is requested and, frequently, a bone marrow examination, together with the analysis of various genetic mutations which, with the rest of the results, allow the diagnosis to be established. In general, most leukemias are of the chronic type, many of them without symptoms and are diagnosed as a result of an analysis performed for other health reasons (routine controls), as opposed to acute leukemias, which very frequently cause a rapid and important deterioration in the general condition.
It is important to explain to the patient that the diagnosis requires sequential examinations and tests and therefore requires a certain amount of time. And it is essential to have a diagnosis of certainty that allows a safe diagnosis to be made in order to establish an adequate prognosis and treatment.