Restoring the infected powerhouse: Mitochondrial quality control in sepsis.

Sepsis is a dysregulated host response to an infection, characterized by organ failure. The pathophysiology is complex and incompletely understood, but mitochondria appear to play a key role in the cascade of events that culminate in multiple organ failure and potentially death. In shaping immune responses, mitochondria fulfil dual roles: they not only supply energy and metabolic intermediates crucial for immune cell activation and function but also influence inflammatory and cell death pathways. Importantly, mitochondrial dysfunction has a dual impact, compromising both immune system efficiency and the metabolic stability of end organs. Dysfunctional mitochondria contribute to the development of a hyperinflammatory state and loss of cellular homeostasis, resulting in poor clinical outcomes. Already in early sepsis, signs of mitochondrial dysfunction are apparent and consequently, strategies to optimize mitochondrial function in sepsis should not only prevent the occurrence of mitochondrial dysfunction, but also cover the repair of the sustained mitochondrial damage. Here, we discuss mitochondrial quality control (mtQC) in the pathogenesis of sepsis and exemplify how mtQC could serve as therapeutic target to overcome mitochondrial dysfunction. Hence, replacing or repairing dysfunctional mitochondria may contribute to the recovery of organ function in sepsis. Mitochondrial biogenesis is a process that results in the formation of new mitochondria and is critical for maintaining a pool of healthy mitochondria. However, exacerbated biogenesis during early sepsis can result in accumulation of structurally aberrant mitochondria that fail to restore bioenergetics, produce excess reactive oxygen species (ROS) and exacerbate the disease course. Conversely, enhancing mitophagy can protect against organ damage by limiting the release of mitochondrial-derived damage-associated molecules (DAMPs). Furthermore, promoting mitophagy may facilitate the growth of healthy mitochondria by blocking the replication of damaged mitochondria and allow for post sepsis organ recovery through enabling mitophagy-coupled biogenesis. The remaining healthy mitochondria may provide an undamaged scaffold to reproduce functional mitochondria. However, the kinetics of mtQC in sepsis, specifically mitophagy, and the optimal timing for intervention remain poorly understood. This review emphasizes the importance of integrating mitophagy induction with mtQC mechanisms to prevent undesired effects associated with solely the induction of mitochondrial biogenesis.

Hospital-related costs of sepsis around the world: A systematic review exploring the economic burden of sepsis.

AIM: The aim of this study was to examine the quality of manuscripts reporting sepsis health care costs and to provide an overview of hospital-related expenditures for sepsis in adult patients around the world. METHODS: We systematically searched the PubMed, EMBASE, Cochrane and Google Scholar to identify relevant studies between January 2010 and January 2022. We selected articles that provided costs and cost-effectiveness analyses, defined sepsis and described their cost calculation method. All costs were adjusted to 2020 US dollars. Medians and interquartile ranges (IQRs) for various costs of sepsis were calculated. The quality of economic studies was assessed using the Drummond 10-item checklist. RESULTS: Overall, 26 studies met our eligibility criteria. The mean total hospital costs per patient varied largely, between €1101 and €91,951. The median (IQR) of the total sepsis costs per country were €36,191 (€17,158 - €53,349), which equals €50 (€34 - €84) per capita annually. The relative amount of healthcare budget spent on sepsis was 2.65%, which equals 0.33% of the gross national product (GNP). CONCLUSION: While general sepsis costs are high, there is considerable variability between countries regarding the costs of sepsis. Further studies examining the impact on sepsis costs, especially on the general ward, can help justify, design and monitor initiatives on prevention, diagnosis, and treatment of this time-critical and potentially preventable disease.