What granulocytes are and what their task is becomes apparent when they are present in the blood in increased or reduced numbers.
The main cause of an increase in granulocytes in the blood is infection or inflammation. Low granulocyte values occur in various diseases or as a side effect of medication. The treating doctor assigns the exact cause after a comprehensive blood test.
Granulocytes – the white defense cells in the blood
The different types of granulocytes
The term granulocytes stands for the numerically largest subgroup of white blood cells, the so-called leukocytes . Their job is to ward off infections caused by bacteria, parasites or fungi. Scientists distinguish granulocytes into three subgroups:
granulocytes. The neutrophilic granulocytes are divided according to the shape of their nuclei into
- mature segmented and
- immature rod-core ones
When does an increased granulocyte count occur?
The so-called granulocytosis , i.e. increased granulocytes , can be associated with an infection, inflammation or chronic inflammatory disease such as rheumatoid arthritis. Other possible causes are certain medications, a disturbed hormone balance or certain types of cancer .
If the blood shows an increased number of immature, rod-nucleated neutrophils, physicians speak of a left shift in the blood count . This may be an indication that the body is fighting infection and even recruiting immature cells from the bone marrow. When there is an increase in eosinophilic granulocytes, doctors speak of eosinophilia.
Such a shift in the blood picture often occurs in connection with allergies, parasite or worm infestation, infectious diseases and even while an infection is subsiding. Other possible causes of eosinophilia include skin or autoimmune diseases and certain types of blood cancer. A rare type of granulocytosis is basophilia, in which there is an increase in basophilic granulocytes. It is associated with diseases that cause increased blood lipid levels or diseases of the blood-forming bone marrow.
When does a reduced granulocyte count occur?
In the case of low granulocytes, the physician speaks of granulocytopenia or, in the almost complete absence of granulocytes, of agranulocytosis . Causes for a low level of blood defense cells are certain infections,
Blood disorders, medications, or enlargement and overactive spleen. Under certain circumstances, there is a reduction in a subgroup of granulocytes. A low number of eosinophils is associated with the following triggers:
- infections,
- Stress,
- during cortisone therapy,
- Cushing’s syndrome, which manifests itself in increased cortisol levels.
Which granulocyte values are normal?
The granulocyte value is given either in absolute terms as thousands (thousands) per microliter (µl) or as a percentage value. The specification in percent puts the granulocytes in relation to other leukocytes . The same applies to the granulocyte value that applies to all values determined by a laboratory.
Only in an overall context do they make sense and indicate the patient’s condition. When interpreting the data, the doctor considers his previous medical history and the patient’s previous illnesses. Changes in the blood count remain meaningless without this information, since the doctor uses many phenomena as causes to explain them. With the appropriate information, the attending physician is able to advise his patient correctly. Values that doctors follow are for adults:
- 1.7 to 7.2 thousand per microliter or 41 to 75 percent for segmented neutrophils ,
- 0.03 to 0.41 thousand per microliter or up to seven percent eosinophils ,
- 0.01 to 0.07 thousand per microliter or up to one percent for basophils.
It should be noted that laboratories use different reference values and determine different values. In addition, they vary according to the time of day and the season without the presence of a disease.
Without the interpretation of a competent physician, individual laboratory values are not meaningful and lead to unnecessary confusion for the patient. They only make sense in connection with other values and over time.
