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Sepsis causes impairment of innate and adaptive immunity by multiple mechanisms, including depletion of immune effector cells and T cell exhaustion. Although lymphocyte dysfunction is associated with increased mortality and potential reactivation of latent viral infection in patients with septic shock, the relation between viral reactivation and lymphocyte dysfunction is obscure. The objectives of this study were 1) to determine the relation of lymphocyte dysfunction to viral reactivation and mortality, and 2) to evaluate recovery of lymphocyte function during septic shock, including T cell receptor (TCR) diversity and the expression of programmed death 1 (PD-1). In 18 patients with septic shock and latent cytomegalovirus (CMV) infection, serial blood samples were obtained on days 1, 3, and 7 after the onset of shock, and immune cell subsets and receptor expression were characterized by flow cytometry. TCR diversity of peripheral blood mononuclear cells was analyzed by Multi-N-plex PCR, and CMV DNA was quantified using a real-time PCR kit. A decrease of TCR diversity and monocyte HLA-DR expression were observed in the early stage of septic shock, while CD4+ T cells displayed an increase of PD-1 expression. Significant lymphopenia persisted for at least 7 days following the onset of septic shock. Normalization of TCR diversity and PD-1 expression was observed by day 7, except in patients who died. CMV reactivation was detected in 3 of the 18 patients during the first week of their ICU stay and all 3 patients died. These changes are consistent with the early stage of immune cell exhaustion and indicate the importance of normal lymphocyte function for recovery from septic shock. Ongoing lymphocyte dysfunction is associated with CMV reactivation and dissemination, as well as with unfavorable outcomes.

Critical Care 2017, 21(Suppl 1):P349 Introduction Imbalance in cellular energetics has been suggested to be an important mechanism for organ failure in sepsis and septic shock. We hypothesized that such energy imbalance would either be caused by metabolic changes leading to decreased energy production or by increased energy consumption. Thus, we set out to investigate if mitochondrial dysfunction or decreased energy consumption alters cellular metabolism in muscle tissue in experimental sepsis. Methods We submitted anesthetized piglets to sepsis (n = 12) or placebo (n = 4) and monitored them for 3 hours. Plasma lactate and markers of organ failure were measured hourly, as was muscle metabolism by microdialysis. Energy consumption was intervened locally by infusing ouabain through one microdialysis catheter to block major energy expenditure of the cells, by inhibiting the major energy consuming enzyme, N+/K + -ATPase. Similarly, energy production was blocked infusing sodium cyanide (NaCN), in a different region, to block the cytochrome oxidase in muscle tissue mitochondria. Results All animals submitted to sepsis fulfilled sepsis criteria as defined in Sepsis-3, whereas no animals in the placebo group did. Muscle glucose decreased during sepsis independently of N+/K + -ATPase or cytochrome oxidase blockade. Muscle lactate did not increase during sepsis in naïve metabolism. However, during cytochrome oxidase blockade, there was an increase in muscle lactate that was further accentuated during sepsis. Muscle pyruvate did not decrease during sepsis in naïve metabolism. During cytochrome oxidase blockade, there was a decrease in muscle pyruvate, independently of sepsis. Lactate to pyruvate ratio increased during sepsis and was further accentuated during cytochrome oxidase blockade. Muscle glycerol increased during sepsis and decreased slightly without sepsis regardless of N+/K + -ATPase or cytochrome oxidase blocking. There were no significant changes in muscle glutamate or urea during sepsis in absence/presence of N+/K + -ATPase or cytochrome oxidase blockade. ConclusionsThese results indicate increased metabolism of energy substrates in muscle tissue in experimental sepsis. Our results do not indicate presence of energy depletion or mitochondrial dysfunction in muscle and should similar physiologic situation be present in other tissues, other mechanisms of organ failure must be considered. , and long-term follow up has shown increased fracture risk [2]. It is unclear if these changes are a consequence of acute critical illness, or reduced activity afterwards. Bone health assessment during critical illness is challenging, and direct bone strength measurement is not possible. We used a rodent sepsis model to test the hypothesis that critical illness causes early reduction in bone strength and changes in bone architecture. Methods 20 Sprague-Dawley rats (350 ± 15.8g) were anesthetised and randomised to receive cecal ligation and puncture (CLP) (50% cecum length, 18G needle single pass through anterior and posterior wa...

Patient: Male, 82Final Diagnosis: Clostridium perfringens infectionSymptoms: Anemia • fever • shockMedication: —Clinical Procedure: Antimicrobial chemotherapySpecialty: Infectious DiseasesObjective:Rare diseaseBackground:Clostridium perfringens (C. perfringens) can cause various infections, including gas gangrene, crepitant cellulitis, and fasciitis. While C. perfringens sepsis is uncommon, it is often rapidly fatal because the alpha toxin of this bacterium induces massive intravascular hemolysis by disrupting red blood cell membranes.Case Report:We present the case of a male patient with diabetes who developed a fatal liver abscess with massive intravascular hemolysis and septic shock caused by toxigenic C. perfringens. The peripheral blood smear showed loss of central pallor, with numerous spherocytes. Multiplex PCR only detected expression of the cpa gene, indicating that the pathogen was C. perfringens type A.Conclusions:C. perfringens infection should be considered in a febrile patient who has severe hemolytic anemia with a very low MCV, hemolyzed blood sample, and negative Coombs test. The characteristic peripheral blood smear findings may facilitate rapid diagnosis.

Components of neutrophil extracellular traps (NETs) are released into the circulation by neutrophils and contribute to microcirculatory disturbance in sepsis. Removing NET components (DNA, histones, and proteases) from the circulation could be a new strategy for counteracting NET-dependent tissue damage. We evaluated the effect of hemoperfusion with a polymyxin B (PMX) cartridge, which was originally developed for treating gram-negative infection, on circulating NET components in patients with septic shock, as well as the effect on phorbol myristate acetate (PMA)-stimulated neutrophils obtained from healthy volunteers. Ex vivo closed loop hemoperfusion was performed through PMX filters in a laboratory circuit. Whole blood from healthy volunteers (incubated with or without PMA) or from septic shock patients was perfused through the circuit. For in vivo experiment blood samples were collected before and immediately after hemoperfusion with PMX to measure the plasma levels of cell-free NETs. The level of cell-free NETs was assessed by measuring myeloperoxidase-associated DNA (MPO-DNA), neutrophil elastase-associated DNA (NE-DNA), and cell-free DNA (cf-DNA). Plasma levels of MPO-DNA, NE-DNA, and cf-DNA were significantly increased after 2 h of PMA stimulation. When the circuit was perfused with blood from septic shock patients or PMA-stimulated neutrophils from healthy volunteers, circulating levels of MPO-DNA, NE-DNA, and cf-DNA were significantly reduced after 1 and 2 h of perfusion with a PMX filter compared with perfusion without a PMX filter. In 10 patients with sepsis, direct hemoperfusion through filters with immobilized PMX significantly reduced plasma levels of MPO-DNA and NE-DNA. These ex vivo and in vivo findings demonstrated that hemoperfusion with PMX removes circulating NET components. Selective removal of circulating NET components from the blood could be effective for prevention/treatment of NET-related inappropriate inflammation and thrombogenesis in patients with sepsis.