Monocytosis is an increase in the level of monocytes in the peripheral blood. Monocytes are cells that belong to the population of leukocytes, or so-called white blood cells, so increases in blood monocytes are mainly associated with infections and other disease states. What are the symptoms of monocytosis? Is monocytosis dangerous?
Monocytosisis a condition when we observe an increase in the level of monocytes in the blood count in the peripheral blood count. Monocytes make up about 3-8% of the total peripheral blood leukocyte population and are the largest of its kind. After maturation, monocytes reach the tissues and then transform into macrophages.
Some monocytes have the properties of stem cells, which means that they can differentiate into other types of cells.
Monocytes are mainly formed in the bone marrow. From the bone marrow they go to the peripheral blood, where they stay for several days, from where they have the ability to reach inflammatory places in the body.
Monocytes produce various compounds that are part of the immune system, such as interferon, leukotrienes and interleukins.
What, however, can be caused by an excess of monocytes in the peripheral blood and what are the reasons for it?
Monocytosis: causes
The causes of monocytosis can roughly be classified as mild or serious.
Due to the fact that monocytes play an important role in the immune system and are phagocytes, i.e. cells that have the ability to cleanse the blood of, among others, bacteria, their production will be increased in various bacterial, viral, fungal or protozoal infections, and in the recovery phase that immediately follows these infections, when the body intensively increases the production of monocytes that were "used up" during the disease.
Monocytosis also occurs in such states as:
- autoimmune diseases, for example systemic lupus erythematosus, rheumatoid arthritis, inflammatory bowel diseases
- haematological diseases: Hodgkin's lymphoma, acute and chronic myelomonocytic leukemia, myeloproliferative neoplasms, multiple myeloma, Waldenström's macroglobulinemia, haemolytic anemia, immune thrombocytopenia
- sarcoidosis
- state after splenectomy (removal of the spleen)
- storage diseases
- condition after steroid therapy
- cirrhosis of the liver
- bone marrow regeneration after radiotherapy or chemotherapy
- use of recombinant human growth factors
- pregnancy
Monocytosis often occurs after infectious diseases, when there is an intensive renewal of leukocytes after infection.
Monocytosis: diagnostics
As you know, monocytes are peripheral blood cells, so their number can be determined using a complete blood count, and more specifically a smear. Most often, automatic smears are made with the use of machines, which is the fastest method.
Blood smear: norms and interpretation
Monocytes (MONO) - role, norm, excess and deficiency
Occasionally, however, automatic smears may confuse us, as monocytes can be confused by the machine with neutrophils, which will result in the misdiagnosis of monocytosis.
In such cases, the result should be confronted with a manual smear. However, this research requires a great deal of experience and skill.
Is monocytosis dangerous?
Each deviation in laboratory tests may cause us anxiety. However, it should be remembered that sometimes an incorrect morphology result results from an error that was made during the diagnosis, so when we find monocytosis, the test should be repeated first.
We always have to take into account the overall picture of the patient, that is, even if we confirm monocytosis in subsequent tests and our patient does not present any clinical symptoms and feels well, we do not have to worry about it.
The most important thing is to remember that we are not treating the results, but the patient.
However, if, in addition to the confirmed monocytosis, we are concerned about something in the medical history or physical examination, the diagnosis should be extended and the patient should be referred to an appropriate specialist.
As you can see, it is very important in the diagnostic process of monocytosis to collect a detailed and reliable interview with the patient.
There can be many causes of monocytosis, but we always have to rule out the most common and the most "harmless" ones first.
Only then do we think about the more serious causes of monocytosis.
Everyone is always worried about cancer, in the case of monocytosis we mainly think of chronic myelomonocytic leukemia.
This disease has chronic monocytosis for more than three months while other possible causes of monocytosis have been ruled out.
Besides thatwe can observe neutropenia or neutrophilia, anemia, sometimes thrombocytopenia, abnormalities in bone marrow and cytogenetic and molecular tests, as well as the presence of fluids in the body cavities.
The clinical symptoms, however, come to the fore, such as:
- weakness
- weight loss
- low fever
- night sweats
- tachycardia
- more susceptible to infections and prolonged bleeding
- skin changes
- enlarged lymph nodes
- enlarged liver
- enlarged spleen
So, as we can see, the overall clinical picture should always be taken into account in the patient's assessment, because a one-off deviation in laboratory tests does not prove anything.