Alterações no hemograma nas infecções virais e bacterianas: uma revisão de literatura

Abstract

The blood count is one of the most frequently requested tests both in emergency situations and in regular clinical practice, playing a crucial role in the diagnosis, monitoring and treatment of various diseases, including infections. This exam is characterized by being economically accessible and its interpretation can be carried out using both manual and automated methods. The latter have contributed to a more agile execution of the exam, providing the presentation of graphs and new hematological parameters.The objective of this work was to present the main changes identified in the blood count during viral and bacterial infections. To this end, a bibliographical research was conducted between the months of June and December 2023, using the scientific databases Scielo, Pubmed and Google Scholar, in addition to consulting reference books in the field of hematology. Specific keywords were used, including "blood count", "viral infection" and "bacterial infection". In the search in English, expressions such as "hematological diseases", "viral infection", "bacterial infection" and "complete blood count" were used.After compiling the information, it was possible to observe how pathogenic agents affect hematopoiesis, influencing the production and maturation of blood cells. 26 articles were gathered that describe the main characteristics of changes in the blood count associated with viral and bacterial infections, highlighting the specific leukocyte predominance in each type of infection. In cases of viral infections, lymphocytosis, reactive lymphocytes, neutropenia and, in some cases, thrombocytopenia were frequently observed. In bacterial infections, the characteristic profile included leukocytosis, neutrophilia and cytoplasmic changes in segmented neutrophils, such as coarse granulations, cytoplasmic vacuolation and Dohle bodies. The presence of a left shift was also identified, indicating the activation of the immune system to combat the pathogen.Understanding these blood count findings highlights the importance of this test for diagnosing and monitoring infections, in addition to enabling the implementation of quick and effective therapeutic strategies.