Currently, there is rationale for separating the systemic manifestations of classical inflammation from systemic inflammation (SI) itself as an independent form of the general pathological process underlying the pathogenesis of the most severe acute and chronic diseases. With this aim in view, we used integral scales of acute and chronic SI (ChSI), including the following blood plasma parameters: interleukins 6, 8, 10; tumor necrosis factor alpha; C-reactive protein; D-dimer; cortisol; troponin I; myoglobin. The presence of multiple organ dysfunction according to the SOFA score was also taken into account. The effectiveness of the scales was tested in groups of intensive care patients during different periods of acute trauma, sepsis, and septic shock. The ChSI scale was applicable under systemic autoimmune diseases, chronic purulent infections, chronic limb threatening ischemia, and end-stage renal disease of various genesis. The number of examined patients was 764 in total. The scales allowed us to verify specific phases of acute SI and identify pathogenetic risk factors of lethal outcomes, as well as the most severe variants of the chronic pathologies course. These scales are open adaptable systems (in terms of the nomenclature and choice of indicators). They are primarily intended for scientific research. However, the SI verification methodology presented in this paper may be useful for developing advanced criteria for assessing both the typical links in the pathogenesis of many diseases and the severity of the overall condition of patients for clinical practice.

We defined Systemic inflammation (SI) as a “typical, multi-syndrome, phase-specific pathological process, developing from systemic damage and characterized by the total inflammatory reactivity of endotheliocytes, plasma and blood cell factors, connective tissue and, at the final stage, by microcirculatory disorders in vital organs and tissues.” The goal of the work: to determine methodological approaches and particular methodical solutions for the problem of identification of SI as a common pathological process. SI can be defined by the presence in plasma of systemic proinflammatory cell stress products—cytokines and other inflammatory mediators, and also by the complexity of other processes signs. We have developed 2 scales: 1) The Reactivity Level scale (RL)–from 0 to 5 points: 0-normal level; RL-5 confirms systemic nature of inflammatory mediator release, and RL- 2–4 defines different degrees of event probability. 2) The SI scale, considering additional criteria along with RL, addresses more integral criteria of SI: the presence of ≥ 5 points according to the SI scale proves the high probability of SI developing. To calculate the RL scale, concentrations of 4 cytokines (IL-6, IL-8, IL-10, TNF-α) and C-reactive protein in plasma were examined. Additional criteria of the SI scale were the following: D-dimers>500ng/ml, cortisol>1380 or <100nmol/l, troponin I≥0.2ng/ml and/or myoglobin≥800ng/ml. 422 patients were included in the study with different septic (n-207) and aseptic (n-215) pathologies. In 190 cases (of 422) there were signs of SI (lethality 38.4%, n-73). In only 5 of 78 cases, lethality was not confirmed by the presence of SI. SI was registered in 100% of cases with septic shock (n-31). There were not significant differences between AU-ROC of CR, SI scale and SOFA to predict death in patients with sepsis and trauma.

The scavenger receptors (SRs)) include > 30 different molecules structurally classified into 11 classes (A to L). They are expressed mostly on stromal macrophages, and their expression may be augmented in direct dependence with concentrations of their ligands. The SRs are heterogenous by their structure, however, being common in their functional potential. E.g., different SR classes may participate in absorption of modified low-density lipoproteins and glycated proteins, apoptotic and ageing cells, altered erythrocytes and platelets, like as a big variety of other endogenous ligands from metabolic and cellular “trash”. A common property of SRs is their participation in removal of small pathogen amounts from blood circulation, regulation of cell and tissue stress responses, ability to form complicated receptor complexes with other receptor types including integrins and toll-like receptors. Opposite to classic pattern-recognizing receptors, the SR involvement does not always elicit a pronounced cellular activation and development of pro-inflammatory cellular stress. The SR functional effects provide interactions between different physiological events and immune system, including the processes of neuroendocrine and metabolic regulation. These mechanisms provide both homeostatic stability and, likewise, act at the border of normal and pathological conditions, i.e., participating in pathogenesis of transitional processes, e.g., physiological ageing. Moreover, the SR-associated processes represent a key pathogenetic factor in different somatic diseases, e.g., those associated with low-intensity chronic inflammation, including obesity, type 2 diabetes, atherosclerosis, arterial hypertension, various neurodegenerative disorders. Similarly, the SRs are involved into the processes of cancer transformation and antitumor response, different processes of classical inflammation, from antigen presentation to the morphofunctional T cell and macrophage polarization in the inflammation foci and immunocompetent organs. SR are playing a controversial role in development of acute systemic inflammation, the main reason for lethal outcomes in the intensive care wards. Targeted effects upon the SRs represent a promising approach when treating a broad variety of diseases, whereas detection of membrane-bound and soluble SR forms could be performed by means of diagnostic and monitoring techniques in many human disorders.

Background: Amniotic fluid embolism (AFE) is one of the main causes of maternal mortality in developed countries. The most critical AFE variants may be considered from the perspective of systemic inflammation (SI), a general pathological process that includes high levels of systemic inflammatory response, neuroendocrine system distress, microthrombosis, and multiple organ dysfunction syndrome (MODS). This research work aimed to characterize the dynamics of super-acute SI using four clinical case studies of patients with critical AFE. Methods: In all the cases, we examined blood coagulation parameters, plasma levels of cortisol, troponin I, myoglobin, C-reactive protein, IL-6, IL-8, IL-10, and TNF-α, and calculated the integral scores. Results: All four patients revealed the characteristic signs of SI, including increased cytokine, myoglobin, and troponin I levels, changes in blood cortisol, and clinical manifestations of coagulopathy and MODS. At the same time, the cytokine plasma levels can be characterized not only as hypercytokinemia, and not even as a “cytokine storm”, but rather as a “cytokine catastrophe” (an increase of thousands and tens of thousands of times in proinflammatory cytokine levels). AFE pathogenesis involves rapid transition from the hyperergic shock phase, with its high levels of a systemic inflammatory response over to the hypoergic shock phase, characterized by the mismatch between low systemic inflammatory response values and the patient’s critical condition. In contrast to septic shock, in AFE there is a much more rapid succession of SI phases. Conclusion: AFE is one of the most compelling examples for studying the dynamics of super-acute SI.

Sepsis-3 Guidelines defines sepsis as an organ dysfunction caused by dysregulated host response to infection. To record organ dysfunction, the SOFA/quick SOFA scales were recommended. In fact, in medical practice, sepsis is considered nothing more than a critical infection that requires intensive care. Therefore, sepsis is pathogenetically a nonhomogeneous condition manifested by diverse nosologies and syndromes. Unlike the previous two editions, Sepsis-1 and Sepsis-2 Guidelines, the formal criteria provided in the Sepsis-3 are closer to the de facto position, describe more specific, but less sensitive features to predict mortality. However, the initial, latent manifestations of critical conditions, which can be relatively effectively controlled by intensive therapy, remain outside the Sepsis-3 criteria. Not all signs of multiple organ dysfunctions (according to the Sepsis-3 criteria) will require intensive care. Hence, obviously the presence or absence of formal criteria of Sepsis-3 will not be always taken into account while verifying sepsis. The only relatively pathogenetically homogeneous definition in Sepsis-3 is “septic shock”. However, it also does not fully consider the staging (according to the degree of compensation of hemodynamic disturbances) and the phasing (according to the severity of the proinflammatory response) of the dynamics of the shock condition. From our point of view, a positive result of the Sepsis-3 consensus would be in transition of the systemic inflammatory response syndrome (SIRS) from the main to additional (optional) verifying sepsis criteria. We also believe that the weak side of the Sepsis-3 Guidelines is in underestimated mechanisms of systemic inflammation as a general pathological process in the genesis of developing critical conditions of various origins. From the perspective of general pathology, sepsis is a combination of the three common fundamental pathological processes: classical (canonical) and systemic inflammation (SI), as well as chronic systemic low-grade inflammation (parainflammation), the latter can be considered as an unfavorable background for development of the former two processes. All three processes are characterized by any SIR signs and require to be differentiated on the basis of integral criteria, which reflect specific blocks of the SI complex process. The pathogenesis of the SARS-CoV-2 infection (COVID-19) is a relevant example underlying inevitability of such approach. The systemic microvascular vasculitis, and its main clinical manifestations such as systemic microcirculatory disorders in the form of shockogenic conditions is the SI pathogenetic basis. Apparently, one of the modalities for further evolution of critical care medicine will be coupled to development of a more multilayered but effective methods for assessing pathogenesis of critical states and more differentiated methods of pathogenetic therapy. Therefore, it will require to modernize a number of fundamental premises in our knowledge about pathobiology, pathophysiology, and general pathology.