Mateusz Michał Gadzała, Aleksandra Paź, Dagmara Mirowska-Guzel

Effect of Glucocorticoids on Peripheral Blood Cell Populations: A Review of Current Evidence

 

2025-10-31

The subject of the study. The subject of the study is the impact of glucocorticoid therapy for non-replacement indications on peripheral blood cell populations. Approximately 2-4% of people worldwide take glucocorticoids due to a range of clinical indications, and this percentage has increased over the past several decades. Better insight into their effects on blood cell count can minimize the risk of misinterpretation of the results in clinical practice and support more effective treatment strategies.

The aim of the study. The aim of the study was to collect, analyse and summarise available information about the potential effect of glucocorticoid therapy on peripheral blood cell populations in patients taking glucocorticoids for non-replacement indications, and to elucidate the possible mechanisms responsible for these effects. This understanding could facilitate a more rational approach to glucocorticoid therapy.

Materials and methods. A review of the scientific literature from 2015 to 2025 was conducted focusing mainly on clinical research concerning the impact of glucocorticoids on peripheral blood cell populations. It also covered preclinical studies. The literature research was performed using the following keywords: „glucocorticoids”, „leukocytes”, „neutrophils”, „lymphocytes”, „eosinophils”, „basophils”, „monocytes”, „macrophages”, „erythrocytes”, „platelets”, „blood cell count”. Particular attention was given to both qualitative and quantitative changes in these cell populations as well as to their probable underlying causes.

Results. Glucocorticoids administration can trigger a range of changes in peripheral blood cell counts. Initial effects appear within minutes after administration. Different cell populations change their numbers and activity. Glucocorticoids cause neutrophilia, qualitatively accompanied by an increase in the number of N2 cells that exhibit anti‑inflammatory activity. Additionally, glucocorticoids lead to a decrease in the total lymphocyte count and their activity in peripheral blood, affecting both B and T lymphocyte subpopulations. Similar alterations have been observed in eosinophils, basophils, and monocytes. Depending on the dose, glucocorticoids can modify the functional profile of monocytes. Glucocorticoid treatment is also likely to increase erythrocyte count in peripheral blood, however, there is no direct clinical evidence confirming this effect. Available data are insufficient to establish the influence of glucocorticoids on platelet count in peripheral blood. Preclinical studies indicate an increase in the number of these cells and their precursors in peripheral blood, but these findings have not been clinically confirmed.

Conclusions. Although glucocorticoids have been widely used in medicine for many years and a wealth of research has been performed so far, the literature still lacks comprehensive explanations for some of their effects and adverse reactions. The impact of glucocorticoids on peripheral blood cell populations remains unknown in many aspects and this offers significant potential for research into the underlying mechanisms. It is essential that doctors from all fields are aware of and consider the possible consequences of glucocorticoid treatment, particularly those that may impact patient safety and the effects of therapy.

Keywords: leukocytes, glucocorticoids, erythrocytes, blood platelets, blood cell count.

© Farm Pol, 2025, 81(2): 123–132