Persistent inflammation and anemia among critically ill septic patients

Impact of red blood cell transfusion and hemoglobin threshold on 1-year mortality among surgical sepsis survivors: A propensity score matching study

BACKGROUND

Despite the fact that red blood cell (RBC) transfusion is commonly applied in surgical intensive care unit (ICU), the effect of RBC transfusion on long-term outcomes remains undetermined. We aimed to explore the association between RBC transfusion and the long-term prognosis of surgical sepsis survivors.

METHODS

This retrospective study was conducted on adult sepsis patients admitted to a tertiary surgical ICU center in China. Patients were divided into transfusion and non-transfusion groups based on the presence of RBC transfusion. Propensity score matching (PSM) and inverse probability of treatment weighting (IPTW)were performed to balance the potential confounders.

RESULTS

A total of 1421 surgical sepsis survivors were enrolled, including 403 transfused patients and 1018 non-transfused patients. There was a significant difference in 1-year mortality between the two groups (23.1 ​% vs 12.7 ​%, HR: 1.539, 95 ​% confidence interval [CI]: 1.030-2.299, P ​< ​0.001). After PSM and IPTW, transfused patients still showed significantly increased 1-year mortality risks compared to non-transfused individuals (PSM: 23.6 ​% vs 15.9 ​%, HR 1.606, 95 ​% CI 1.036-2.488 ​P ​= ​0.034; IPTW: 20.1 ​% vs 12.9 ​%, HR 1.600, 95 ​% CI 1.040-2.462 ​P ​= ​0.032). Among patients with nadir hemoglobin below 70 ​g/L, 1-year mortality risks in both groups were similar (HR 1.461, 95 ​% CI 0.909-2.348, P ​= ​0.118). However, among patients with nadir hemoglobin above 70 ​g/L, RBC transfusion was correlated with increased 1-year mortality risk (HR 1.556, 95 ​% CI 1.020-2.374, P ​= ​0.040).

CONCLUSION

For surgical sepsis survivors, RBC transfusion during ICU stay was associated with increased 1-year mortality, especially when patients show hemoglobin levels above 70 ​g/L.

Effects of Antithrombin on Persistent Inflammation, Immunosuppression, and Catabolism Syndrome among Patients with Sepsis-Induced Disseminated Intravascular Coagulation

Persistent inflammation, immunosuppression, and catabolism syndrome (PICS) is a serious condition after critical care. We examined the efficacy of antithrombin, which may attenuate coagulopathy with the control of inflammation, for PICS among patients with sepsis-induced disseminated intravascular coagulation (DIC). The present study used the inpatient claims database with laboratory findings to identify patients admitted to intensive care units and diagnosed with sepsis and DIC. A composite of the incidence of PICS on day 14 or 14-day mortality as the primary outcome was compared between the antithrombin and control groups using a propensity-score-matched analysis. Secondary outcomes were the incidence of PICS on day 28, 28-day mortality, and in-hospital mortality. A total of 324 well-balanced matched pairs were generated from 1622 patients. The primary outcome did not differ between the antithrombin and control groups (63.9% vs. 68.2%, respectively, p = 0.245). However, the incidences of 28-day and in-hospital mortality were significantly lower in the antithrombin group (16.0% vs. 23.5% and 24.4% vs. 35.8%, respectively). Similar results were obtained in a sensitivity analysis using overlap weighting. Antithrombin did not reduce the occurrence of PICS on day 14 in patients with sepsis-induced DIC; however, it was associated with a better mid-term (day 28) prognosis.

Chronic Critical Illness in Patients With Sepsis is Associated With Persistent Anemia, Inflammation, and Impaired Functional Outcomes

INTRODUCTION

Survivors of sepsis will progress towards rapid recovery (RAP) or enter a state of persistent organ dysfunction and chronic critical illness (CCI). Independently, anemia is known to be a significant factor in functional recovery of hospitalized patients. This study aims to analyze long-term hemoglobin levels and functional outcomes following RAP and CCI.

METHODS

A prospective, cohort study was performed in septic patients who were stratified into RAP (N = 54) with ICU length of stay < 14 days or CCI (N = 63) with ICU length of stay > 14 days. CBC and plasma inflammatory markers were measured on the day of enrollment, weekly until day 42, then at 3 and 6 months. Functional outcomes using Zubrod scale, gait speed test, and total short physical performance battery (SPPB) were assessed at 3, 6, and 12 months.

RESULTS

Mean age was 59 years (range: 20-83) and 62% were male. Hemoglobin was significantly decreased at 3 and 6 months in CCI compared to RAP (8.9* and 9.2* vs 10.4 and 11.1 g/dL), despite receiving significantly more red blood cell transfusions. CCI patients had persistent elevation of CRP, IL-6 and TNF-α. CCI patients had worse functional outcome with a significantly higher Zubrod score, and lower SPPB, and gait speed score at 3, 6, and 12 months.

CONCLUSION

Despite receiving more pRBC transfusions, CCI patients had a persistent anemia that was associated with chronic systemic inflammation and poor functional outcomes six months following sepsis. Alleviating prolonged inflammation could improve persistent anemia and functional outcomes in CCI patients.

Anemia Recovery after Trauma: A Longitudinal Study

Background: Post-injury inflammation and its correlation with anemia recovery after severe trauma is poorly described. Severe injury induces a systemic inflammatory response associated with critical illness and organ dysfunction, including disordered hematopoiesis, and anemia. This study sought to characterize the resolution of post-injury inflammation and anemia to identify risk factors associated with persistence of anemia. Patients and Methods: This single-institution study prospectively enrolled 73 trauma patients with an injury severity score >15, hemorrhagic shock, and a lower extremity long bone orthopedic injury. Blood was obtained at enrollment and after 14 days, one, three, and six months. Analytes were compared using Mann-Whitney U tests with correction for multiple comparisons. Results: Median age was 45 years and Injury Severity Score (ISS) was 27, with anemia rates of 97% at two weeks, 80% at one month, 52% at three months, and 30% at six months. Post-injury elevations in erythropoietin, interleukin-6, and C-reactive protein resolved by one month, three months, and six months, respectively. Median granulocyte colony-stimulating factor (G-CSF) and tumor necrosis factor (TNF)-α concentrations remained elevated throughout the six-month follow-up period. Patients with persistent anemia had longer intensive care unit and hospital lengths of stay, more infectious complications, and received more packed red blood cell transfusions compared to those with early anemia recovery. Conclusions: Severe trauma is associated with a prolonged inflammatory response, which is associated with increased transfusion requirements, lengths of stay, and persistent anemia. Further analysis is needed to identify correlations between prolonged inflammation and clinical outcomes after discharge.

Haemoglobin value and red blood cell transfusions in prolonged weaning from mechanical ventilation: a retrospective observational study

INTRODUCTION

The role of haemoglobin (Hb) value and red blood cell (RBC) transfusions in prolonged weaning from mechanical ventilation (MV) is still controversial. Pathophysiological considerations recommend a not too restrictive transfusion strategy, whereas adverse effects of transfusions are reported. We aimed to investigate the association between Hb value, RBC transfusion and clinical outcome of patients undergoing prolonged weaning from MV.

METHODS

We performed a retrospective, single-centred, observational study including patients being transferred to a specialised weaning unit. Data on demographic characteristics, comorbidities, current and past medical history and the current course of treatment were collected. Weaning failure and mortality were chosen as primary and secondary endpoint, respectively. Differences between transfused and non-transfused patients were analysed. To evaluate the impact of different risk factors including Hb value and RBC transfusion on clinical outcome, a multivariate logistic regression analysis was used.

RESULTS

184 patients from a specialised weaning unit were analysed, of whom 36 (19.6%) failed to be weaned successfully. In-hospital mortality was 18.5%. 90 patients (48.9%) required RBC transfusion during the weaning process, showing a significantly lower Hb value (g/L) (86.3±5.3) than the non-transfusion group (95.8±10.5). In the multivariate regression analysis (OR 3.24; p=0.045), RBC transfusion was associated with weaning failure. However, the transfusion group had characteristics indicating that these patients were still in a more critical state of disease.

CONCLUSIONS

In our analysis, the need for RBC transfusion was independently associated with weaning failure. However, it is unclear whether the transfusion itself should be considered an independent risk factor or an additional symptom of a persistent critical patient condition.

Mechanisms of improved erythroid progenitor growth with removal of chronic stress after trauma

BACKGROUND

Erythropoietic dysfunction after trauma and critical illness is associated with anemia, persistent inflammation, increased hematopoietic progenitor cell mobilization from the bone marrow, and reduced erythroid progenitor growth. Yet the duration and reversibility of these postinjury bone marrow changes remain unknown. This study sought to determine whether removal of chronic postinjury stress could induce improvements in erythroid progenitor growth.

METHODS

Sprague-Dawley rats (n = 8-11/group) were assigned to the following: naïve, lung contusion and hemorrhagic shock, lung contusion and hemorrhagic shock plus daily chronic stress for 7 days followed by 7 days of routine handling to allow recovery (lung contusion and hemorrhagic shock + chronic stress 7), or lung contusion and hemorrhagic shock plus chronic stress for 14 days (lung contusion and hemorrhagic shock + chronic stress 14). Circulating CD117⁺CD71⁺ erythroid progenitors were detected by flow cytometry. Rodents were killed on day 14, and bone marrow erythroid progenitor growth and erythroid transcription factors were assessed. Differences were assessed by analysis of variance (P < .05).

RESULTS

Compared to lung contusion and hemorrhagic shock + chronic stress 14, lung contusion and hemorrhagic shock + chronic stress 7 rodents had improved hemoglobin (8% ± 10% increase vs 6% ± 10% decrease) with fewer mobilized erythroid progenitors (898 × vs 1,524 cells), lower granulocyte-colony stimulating factor levels (3.1 ± 1.1 × pg/mL vs 5.9 ± 1.8 pg/mL), and improved erythroid progenitor growth. Cessation of stress had no impact on erythroid transcription factors GATA-1, GATA-2, LMO2, or KLF1.

CONCLUSION

Improvements in erythroid progenitor growth and reduced hematopoietic progenitor cell mobilization were seen 7 days after cessation of chronic stress and were associated with an improvement in hemoglobin. Early bone marrow erythropoietic functional recovery may result from resolution of hematopoietic progenitor mobilization rather than upregulation of pro-erythroid transcription factors. This study suggests that postinjury anemia is reversible and has the potential to improve with the cessation of stress.

Zinc protoporphyrin levels in COVID-19 are indicative of iron deficiency and potential predictor of disease severity

Background

Coronavirus disease (COVID-19) has a severe impact on all aspects of patient care. Among the numerous biomarkers of potential validity for diagnostic and clinical management of COVID-19 are biomarkers at the interface of iron metabolism and inflammation.

Methods

The follow-up study included 54 hospitalized patients with laboratory-confirmed COVID-19 with a moderate and severe/critical form of the disease. Iron deficiency specific biomarkers such as iron, ferritin, transferrin receptor, hepcidin, and zinc protoporphyrin (ZnPP) as well as relevant markers of inflammation were evaluated twice: in the first five days when the patient was admitted to the hospital and during five to 15 days; and their validity to diagnose iron deficiency was further assessed. The regression and Receiver Operating Characteristics (ROC) analyses were performed to evaluate the prognosis and determine the probability for predicting the severity of the disease in the first five days of COVID-19.

Results

Based on hemoglobin values, anemia was observed in 21 of 54 patients. Of all iron deficiency anemia-related markers, only ZnPP was significantly elevated (P<0.001) in the anemic group. When patients were grouped according to the severity of disease, slight differences in hemoglobin or other anemia-related parameters could be observed. However, the levels of ZnPP were significantly increased in the severely ill group of patients. The ratio of ZnPP to lymphocyte count (ZnPP/L) had a discrimination power stronger than the neutrophil to lymphocyte count ratio (N/L) to determine disease severity. Additionally, only two markers were independently associated with the severity of COVID-19 in logistic regression analysis; D-dimer (OR (5.606)(95% CI 1.019–30.867)) and ZnPP/L ratio (OR (74.313) (95% CI 1.081–5108.103)).

Conclusions

For the first time ZnPP in COVID-19 patients were reported in this study. Among all iron-related markers tested, ZnPP was the only one that was associated with anemia as based on hemoglobin. The increase in ZnPP might indicate that the underlying cause of anemia in COVID-19 patients is not only due to the inflammation but also of nutritional origin. Additionally, the ZnPP/L ratio might be a valid prognostic marker for the severity of COVID-19.

Erythrocyte degradation, metabolism, secretion, and communication with immune cells in the blood during sepsis: A review

Sepsis is a health issue that affects millions of people worldwide. It was assumed that erythrocytes were affected by sepsis. However, in recent years, a number of studies have shown that erythrocytes affect sepsis as well. When a pathogen invades the human body, it infects the blood and organs, causing infection and sepsis-related symptoms. Pathogens change the internal environment, increasing the levels of reactive oxygen species, influencing erythrocyte morphology, and causing erythrocyte death, i.e., eryptosis. Characteristics of eryptosis include cell shrinkage, membrane blebbing, and surface exposure of phosphatidylserine (PS). Eryptotic erythrocytes increase immune cell proliferation, and through PS, attract macrophages that remove the infected erythrocytes. Erythrocyte-degraded hemoglobin derivatives and heme deteriorate infection; however, they could also be metabolized to a series of derivatives. The result that erythrocytes play an anti-infection role during sepsis provides new perspectives for treatment. This review focuses on erythrocytes during pathogenic infection and sepsis.

Transcriptomic Changes Within Human Bone Marrow After Severe Trauma

BACKGROUND

Severe trauma is associated with severe systemic inflammation and neuroendocrine activation that is associated with erythroid progenitor growth suppression and refractory anemia. Although distinct transcriptional profiles have been detected in numerous tissue types after trauma, no study has yet characterized this within the bone marrow. This study sought to identify a unique bone marrow transcriptomic response following trauma.

METHODS

In a prospective observational cohort study, bone marrow was obtained from severely injured trauma patients with a hip or femur fracture (n = 52), elective hip replacement patients (n = 33), and healthy controls (n = 11). RNA was isolated from bone marrow using a Purelink RNA mini kit. Direct quantification of mRNA copies was performed by NanoString Technologies on a custom gene panel.

RESULTS

Trauma patients displayed an upregulation of genes encoding receptors known to have inhibitory downstream effects on erythropoiesis, including ferroportin, interleukin-6 (IL-6) receptor, transforming growth factor-beta (TGF-β) receptor, and IL-10, as well as genes involved in innate immunity including toll-like receptor 4 (TLR4)-mediated signaling factors. In contrast, hip replacement patients had downregulated transcription of IL-1β, IL-6, TGF-β, tumor necrosis factor alpha, and the HAMP gene with no change in TLR4-mediated signaling factors.

CONCLUSIONS

A unique transcriptomic response within the bone marrow was identified following severe trauma compared to elective hip replacement. These transcriptomic differences were related to the innate immune response as well as known inhibitors of erythropoiesis. Although confined to just one time point, this differential transcriptional response may be linked to refractory anemia and inflammation after injury.

Iron in infection and immunity

Iron is an essential micronutrient for virtually all living cells. In infectious diseases, both invading pathogens and mammalian cells including those of the immune system require iron to sustain their function, metabolism and proliferation. On the one hand, microbial iron uptake is linked to the virulence of most human pathogens. On the other hand, the sequestration of iron from bacteria and other microorganisms is an efficient strategy of host defense in line with the principles of 'nutritional immunity'. In an acute infection, host-driven iron withdrawal inhibits the growth of pathogens. Chronic immune activation due to persistent infection, autoimmune disease or malignancy however, sequesters iron not only from infectious agents, autoreactive lymphocytes and neoplastic cells but also from erythroid progenitors. This is one of the key mechanisms which collectively result in the anemia of chronic inflammation. In this review, we highlight the most important interconnections between iron metabolism and immunity, focusing on host defense against relevant infections and on the clinical consequences of anemia of inflammation.

Disseminated Intravascular Coagulopathy Is Associated with the Outcome of Persistent Inflammation, Immunosuppression and Catabolism Syndrome

Persistent inflammation, immunosuppression and catabolism syndrome (PIICS) often occur after critical care. Disseminated intravascular coagulation (DIC) is expected to be associated independently with PIICS development. We retrospectively analyzed 5397 patients admitted to the Hitachi General Hospital emergency and critical care center during four years. We classified PIICS as C-reactive protein > 3.0 mg/dL or albumin < 3.0 g/dL or lymphocyte count < 800/μL on day 14. Prolonged hospital stay (>14 days) without PIICS and early recovery (discharged alive within 14 days) were assigned as non-PIICS. Early death (death within 14 days) was identified. We analyzed the association between the International Society on Thrombosis and Haemostasis overt DIC and PIICS outcomes. Results revealed 488 PIICS, 416 early death and 4493 non-PIICS cases. Analyses showed DIC as associated significantly with mortality, the Barthel index at discharge and PIICS development. Multivariate regression analysis and a generalized structural equation model identified DIC on admission as an independent risk factor for PIICS in surviving patients.

Mortality and morbidity of low-grade red blood cell transfusions in septic patients: a propensity score-matched observational study of a liberal transfusion strategy

Background

Red blood cell (RBC) transfusions are associated with risks including immunological reactions and volume overload. Current guidelines suggest a restrictive transfusion strategy in most patients with sepsis but based on previous randomized controlled trials and observational studies, there are still uncertainties about the safety in giving low-grade RBC transfusions to patients with sepsis.

Methods

Critically ill patients with severe sepsis or septic shock admitted to a university hospital intensive care unit between 2007 and 2018 that received less or equal to 2 units of RBCs during the first 5 days of admission were propensity score matched to controls. Outcomes were 90- and 180-day mortality, highest acute kidney injury network (AKIN) score the first 10 days, days alive and free of organ support the first 28 days after admission to the intensive care unit and highest sequential organ failure assessment score (SOFA-max).

Results

Of 9490 admissions, 1347 were diagnosed with severe sepsis or septic shock. Propensity-score matching resulted in two well-matched groups with 237 patients in each. The annual inclusion rate in both groups was similar. The median hemoglobin level before RBC transfusion was 95 g/L (interquartile range 88–104) and the majority of the patients were transfused in first 2 days of admission. Low-grade RBC transfusion was associated with increased 90- and 180-day mortality with an absolute risk increase for death 9.3% (95% confidence interval: 0.6–18%, P = 0.032) and 11% (95% confidence interval: 1.7–19%, P = 0.018), respectively. Low-grade RBC transfusion also correlated with increased kidney, circulatory and respiratory failure and higher SOFA-max score.

Conclusions

Low-grade RBC transfusion during the first 5 days of admission was associated with increased mortality and morbidity in a liberal transfusion setting. The results support the current practice of a restrictive transfusion strategy in septic critically ill patients.

Chronic Critical Illness Patients Fail to Respond to Current Evidence-Based Intensive Care Nutrition Secondarily to Persistent Inflammation, Immunosuppression, and Catabolic Syndrome

BACKGROUND

Sepsis-induced multiple-organ failure (MOF) has plagued surgical intensive care units (ICUs) for decades. Early nutrition (principally enteral) improves hospital outcomes of high-risk ICU patients. The purpose of this study is to document how the growing epidemic of chronic critical illness (CCI) patients responds to adequate evidence-based ICU nutrition.

METHODS

This retrospective post hoc subgroup analysis of an ongoing sepsis database identified 56 CCI patients who received early, adequate nutrition per an established surgical ICU protocol compared with 112 matched rapid-recovery (RAP) patients.

RESULTS

The matched CCI and RAP groups had similar baseline characteristics. Serial biomarkers showed that CCI patients remained persistently inflamed with ongoing stress metabolism and that despite receiving evidence-based protocol nutrition, they had persistent catabolism and immunosuppression with more secondary infections. More CCI patients were discharged to poor nonhome destinations (ie, skilled nursing facilities, long-term acute care, hospice) (81% vs 29%, P < 0.05). At 12-month follow-up, CCI patients had worse functional status by Zubrod score (3.17 vs 1.62, P < 0.001) and Short Physical Battery Testing (4.78 vs 8.59, P < 0.02), worse health-related quality of life by EQ-5D-3L descriptive measures (9.07 vs 7.45, P < 0.003), and lower survival (67% vs 92%, P < 0.05).

CONCLUSIONS

Despite early, adequate, evidence-based ICU nutrition, septic surgical ICU patients who develop CCI exhibit persistent inflammation, immunosuppression, and catabolism with unacceptable long-term morbidity and mortality. Although current evidence-based ICU nutrition may improve short-term ICU outcomes, novel adjuncts are needed to improve long-term outcomes for CCI patients.

Sepsis Immunometabolism: From Defining Sepsis to Understanding How Energy Production Affects Immune Response

OBJECTIVES

This review will examine current definitions and trends in sepsis management as well pathophysiologic mechanisms in animal and ex vivo studies that correlate decreased energy production with deranged inflammatory response during the septic process.

DATA SOURCES

The latest articles in the literature that focus on the role of immunometabolism and associated mechanisms in sepsis were selected.

STUDY SELECTION

The most relevant, original articles were included in the review.

DATA EXTRACTION

All pertinent data for sepsis definitions as well as changes in immunometabolic pathways during the septic process was reviewed and assessed for inclusion in this article.

DATA SYNTHESIS

Sepsis is a major cause of multiple organ dysfunction. It is the principal cause of death resulting from infection and one of the most expensive conditions treated in the United States. Despite current efforts to accurately define sepsis, novel treatments and highly trained providers, mortality rates for sepsis remain high, prompting a need for further investigation of underlying immunometabolic mechanisms to identify potential treatment targets. The definition of sepsis has shifted and changed in the past few decades due to poorly defined criteria, as well as unclear guidelines for providers with regards to management of severe sepsis and septic shock. The early identification of patients with a systemic inflammatory response that will progress to septic shock is critical since recent traditional therapeutic approaches, such as early goal-directed therapy, IV immunoglobulin, and anti-tumor necrosis factor-α antibodies have failed.

CONCLUSIONS

There are no effective anti-sepsis drug therapies due to complex inflammatory and metabolic interactions. Further studies regarding the interface between innate immunity and metabolism should be investigated to effectively address septic patient mortality rates.

T Cell- and Monocyte-Specific RNA-Sequencing Analysis in Septic and Nonseptic Critically Ill Patients and in Patients with Cancer

Sepsis is characterized as life-threatening organ dysfunction caused by a dysregulated host immune response to infection. The purpose of this investigation was to determine the differential effect of sepsis on innate versus adaptive immunity, in humans, by examining RNA expression in specific immune cell subsets, including monocytes/macrophages and CD4 and CD8 T cells. A second aim was to determine immunosuppressive mechanisms operative in sepsis that might be amenable to immunotherapy. Finally, we examined RNA expression in peripheral cells from critically ill nonseptic patients and from cancer patients to compare the unique immune response in these disorders with that occurring in sepsis. Monocytes, CD4 T cells, and CD8 T cells from septic patients, critically ill nonseptic patients, patients with metastatic colon cancer, and healthy controls were analyzed by RNA sequencing. Sepsis induced a marked phenotypic shift toward downregulation of multiple immune response pathways in monocytes suggesting that impaired innate immunity may be fundamental to the immunosuppression that characterizes the disorder. In the sepsis cohort, there was a much more pronounced effect on gene transcription in CD4 T cells than in CD8 T cells. Potential mediators of sepsis-induced immunosuppression included Arg-1, SOCS-1, and SOCS-3, which were highly upregulated in multiple cell types. Multiple negative costimulatory molecules, including TIGIT, Lag-3, PD-1, and CTLA-4, were also highly upregulated in sepsis. Although cancer had much more profound effects on gene transcription in CD8 T cells, common immunosuppressive mechanisms were present in all disorders, suggesting that immunoadjuvant therapies that are effective in one disease may also be efficacious in the others.

Serum Interleukin-8 in Patients with Different Origin of Intra-Abdominal Infections in Perioperative Period

Intra-abdominal infections (IAI) are associated with high levels of pro-inflammatory serum IL-8 and poor outcomes, but data on IL-8 levels in various inflammatory reactions are contradictory. A better understanding of the diagnostic role of IL-8 is important, since the clinical relevance remains unclear. Methods: That was a single-center observational longitudinal cross-sectional study included 56 patients with various origins of intra-abdominal infections: 24 patients with postoperative abscesses, 12 patients with primary intra-abdominal abscesses, and 20 patients with diffuse peritoneal collection. Perioperative serum concentrations of interleukin-8 IL-8 were investigated at the day before surgery, on the 2nd–3rd day, and on the 5th–7th day after surgery. The hypothesis suggested that there was a difference in serum IL-8 in patients with IAI of different origin in the perioperative period. Results: The study showed that the level of serum IL-8 in patients with intra-abdominal infections of different origins is lower in comparison with healthy individuals. Despite the fact that we did not detect any statistically significant differences in the level of IL-8 in serum in IAI of different origin in the perioperative period, its lowest index was observed in the patients with postoperative abscesses on the 5th–7th days after surgical intervention. The levels of serum IL-8 ≤49.71 pg/mL and ≤48.88 pg/mL may serve as diagnostic markers for primary and postoperative abscesses with significant sensitivity and specificity. Conclusions: Our results differ from previous studies that showed high serum IL-8. High-quality clinical trials are needed to better comprehend the role of inflammatory mediators in IAI with different origin.

Inflammatory anemia-associated parameters are related to 28-day mortality in patients with sepsis admitted to the ICU: a preliminary observational study

Background

Anemia is one of the most common complications of sepsis. Sepsis-related anemia is associated mainly with inflammation. We aimed to observe the changes in the inflammatory anemia-associated parameters of patients with sepsis in the early stage of intensive care unit (ICU) admission and to evaluate their association with 28-day mortality.

Methods

A total of 198 patients with sepsis were divided into survivor (n = 110) and non-survivor (n = 88) groups on the basis of 28-day survival. Healthy volunteers (n = 20) were enrolled as a control group. Plasma levels of iron, ferritin, erythropoietin (EPO), soluble transferrin receptor (sTfR), hepcidin, interleukin-6 (IL-6), hemoglobin and the red blood cell distribution width (RDW) were measured on days 1, 3 and 7 of ICU admission. Clinical data and laboratory findings were collected, and the Sequential Organ Failure Assessment (SOFA) score was calculated.

Results

Patients with sepsis showed significant decreases in hemoglobin, plasma iron and sTfR/log ferritin and significant increases in plasma EPO, sTfR, hepcidin, ferritin and IL-6 on days 1, 3 and 7 of ICU admission compared with healthy volunteers. Hemoglobin was correlated negatively with plasma IL-6 and hepcidin. In patients with sepsis, non-survivors had significantly lower plasma iron, EPO and sTfR/log ferritin, but higher plasma hepcidin, ferritin and IL-6 than survivors on days 1, 3 and 7 of ICU admission. Plasma EPO, hepcidin, ferritin, IL-6, sTfR/log ferritin, the RDW and SOFA score were associated significantly with 28-day mortality but to a varying extent. In particular, in predicting 28-day mortality, plasma hepcidin had an area under the receiver operating curve of 0.808 and 87.3% specificity, which was the highest among the inflammatory anemia-associated parameters tested.

Conclusions

Inflammatory anemia-associated parameters changed significantly in patients with sepsis in the first week of ICU admission. Plasma EPO, hepcidin, ferritin, IL-6, sTfR/log ferritin, the RDW and SOFA score were associated significantly with 28-day mortality. Plasma hepcidin might have a superior predictive value, with high specificity, compared with other inflammatory anemia-associated parameters for 28-day mortality of sepsis patients in the ICU.

Electronic supplementary material

The online version of this article (10.1186/s13613-019-0542-7) contains supplementary material, which is available to authorized users.