Pathological Alterations in Human Blood Microbiome—An Up‐Dated Review

The main source of microorganisms in the blood is the intestinal and oral microflora through the route of atopobiosis. It is clear that the blood microbiome undergoes signifi-cant changes in response to various pathological conditions within the human body. In this review, we summarized data from studies of the human blood microbiome in diseas-es of the nervous system, cardiovascular, respiratory, liver, kidney, and metabolite disor-ders. Links between blood microbiome and the above mentioned diseases were demon-strated. In support of this understanding, it is evident that analogous alterations in microbiome composition occur across various disease categories; however, the microbial signatures associated with the blood microbiome exhibit specificity. For instance, elevated abundancy of Proteobacteria have been identified in cardiovascular, renal, and metabolic disorders. Conversely, while Firmicutes are found to be abundant in renal and metabolic conditions, their levels are diminished in cardiovascular diseases. Additionally, patients suffering from respiratory and liver ailments typically show a heightened presence of Bacteroidetes; notably, Flavobacterium is prevalent in respiratory diseases, whereas Enterobacteriaceae is associated with liver diseases. Hence, human blood microbiome could be considered as potentiаl biomarker in certain diseases.