Tumor necrosis factor gene polymorphism and septic shock in surgical infection

Effect of shenfu injection in patients with septic shock: A systemic review and meta-analysis for randomized clinical trials

ETHNOPHARMACOLOGICAL RELEVANCE

Shenfu injection (SFI) is a well-known Chinese herbal medicine widely used in the treatment of septic shock in China.

AIM OF THE STUDY

To explore the clinical safety and effectiveness of combined application of Shenfu injection in the treatment of septic shock on the basis of routine western medical treatment.

MATERIALS AND METHODS

Randomized controlled trials published before February 28, 2022 in patients with septic shock were searched in the Chinese Biomedical Literature Service System (SinoMed), Embase, PubMed, Cochrane Library, WOS, Scopus. Stata 15.0 and R 4.2.2 were used to meta-analyze sequential organ failure assessment (SOFA) score, case fatality rate, mean arterial pressure (MAP), arterial lactate (Lac). Adverse effects were analyzed by description.

RESULTS

A total of 904 articles were searched and 56 RCTs were included, with a total of 4279 participants. Among them, there were 2148 cases in the SFI group and 2131 cases in the control group. The meta-analysis showed that, comparing with routine western medical therapy, the combined use of SFI could effectively reduce 24 h SOFA (MD = -0.79, 95%CI: (-1.12) - (-0.46)), 72 h SOFA (MD = -1.53, 95%CI: (-1.89) - (-1.17)) and 7 d SOFA (MD = -1.55; 95%CI: (-2.86) - (-0.24)). Besides, combined use of SFI could reduce 14 d case fatality rate (RR = 0.16, 95% CI: 0.07-0.37) and 28 d case fatality rate (RR = 0.82, 95% CI: 0.71-0.95). While SFI group showed almost the same effect in 7 d case fatality rate as control (RR: 0.76; 95% CI: 0.42-1.37; P = 0.37). SFI could increase 6 h MAP (MD = 6.40, 95% CI: 3.43-9.37) and 24 h MAP (MD = 4.79, 95% CI: 1.62-7.95). Additionally, SFI could decrease 6 h Lac (MD = -0.90, 95% CI: (-1.34) - (-0.45)), 24 h Lac (MD = -0.80, 95% CI: (-1.20) - (-0.40)), 48 h Lac (MD = -0.67, 95% CI: (-1.05) - (-0.29)).

CONCLUSIONS

Shenfu injection combined with RWT showed better therapeutic effect than RWT. SFI plus RWT can improve clinical prognosis of patients with septic shock.

Proinflammatory cytokines levels in sepsis and healthy volunteers, and tumor necrosis factor-alpha associated sepsis mortality: A systematic review and meta-analysis

BACKGROUND

Sepsis is a global health challenge associated with significant morbidity and mortality. Detrimental sepsis effects are attributed to excessive inflammation or a "cytokine storm." However, anti-inflammation therapies have failed to lower sepsis mortality. We aim to characterize levels of key inflammatory cytokines in patients with sepsis and compare levels with those in healthy individuals and relate tumor necrosis factor (TNF) α levels to patient characteristics and outcomes.

METHODS

We performed a systematic review and meta-analysis. Medline, Embase, Cochrane Library, and Web of Science Core Collection databases were searched between 1985 and May 2020. Analysis was restricted to studies in English. We included randomized controlled trials (RCTs), controlled trials, cohort studies, case series, and cross-sectional studies that reported mean levels of cytokines in the circulation thought to be relevant for sepsis pathogenesis. We also evaluated concentrations of these cytokines in healthy individuals. The Quality in Prognosis Studies tool was used to assess the methodological quality of included studies. We extracted summary data from published reports. Data analyses were performed using a random-effects model to estimate pooled odds ratios (OR) with 95% confidence intervals for cytokine levels and mortality. This systematic review is registered in PROSPERO (CRD42020179800).

FINDINGS

We identified 3654 records, and 104 studies were included with a total of 3250 participants. The pooled estimated mean TNFα concentration in sepsis patients was 58.4 pg/ml (95% Confidence Interval or CI 39.8-85.8 pg/ml), and in healthy individuals was 5.5 pg/ml (95% CI 3.8-8.0 pg/ml). Pooled estimate means for IL-1β and IFN-γ in sepsis patients were 21.8 pg/ml and 63.3 pg/ml, respectively. Elevated TNFα concentrations associated with increased 28-day sepsis mortality (p = 0.001). In subgroup analyses, we did not detect an association between TNFα levels and sepsis source, sepsis severity, or sequential organ failure assessment (SOFA) score. A TNF-α cutoff level ≥14.7 pg/ml separated sepsis patients from healthy individuals with a sensitivity of 82.6%, a specificity of 91.7%, and a likelihood ratio of 9.9.

INTERPRETATION

Sepsis mean TNFα concentration is increased approximately 10-fold compared to mean concentration in healthy individuals, and TNFα associated with sepsis mortality but not sepsis severity. The concept that elevated cytokines cause sepsis should be revisited in the context of these data.

FUNDING

None.

Variants in TNF and NOS3 (eNOS) genes associated with sepsis in adult patients

BACKGROUND

Sepsis is a life-threatening condition caused by a dysregulated host response to infections and is a leading cause of death in hospitalized patients. The present study aimed to elucidate the possible association between sepsis and the tumor necrosis factor (TNF) gene -308G/A (rs1800629) polymorphism, as well as endothelial nitric oxide synthase (eNOS, NOS3) gene -786T/C (rs2070744), 4a/4b (27 bp-VNTR in intron 4, rs61722009) and 894G/T (Glu298Asp, rs1799983) polymorphisms.

METHODS

In total, 188 septic adult cases and 188 healthy controls were enrolled. Genomic DNAs from the controls and patients were analyzed by polymerase chain reaction and restriction fragment length polymorphism methods.

RESULTS

There were significant associations between the G/G genotype and G allele of the TNF -308G/A (rs1800629) polymorphism in the sepsis group (p < 0.001). The presence of the T/C genotype (p = 0.002) and C allele (p = 0.001) of the -786T/C (rs2070744) was markedly associated with an increased risk of sepsis. However, no significant associations were found with 4a/4b (27 bp-VNTR in intron 4, rs61722009) and 894G/T (Glu298Asp, rs1799983) polymorphisms. Higher 4bGC and lower 4bTT haplotype frequencies were associated with sepsis.

CONCLUSIONS

Our results strongly suggest that TNF gene (-308G/A, rs1800629) and NOS3 gene -786T/C (rs2070744) polymorphisms may modify individual susceptibility to sepsis in the Turkish population.

Matrix metalloproteinase-9 -1562 C/T polymorphism is associated with the risk of sepsis in a Chinese population: A retrospective study

Matrix metalloproteinase-9 (MMP-9) has been shown to participate in the pathogenesis of sepsis. In this study, we recruited 312 sepsis patients and 413 controls to explore the relationship between sepsis risk and the MMP-9 -1562 C/T polymorphism in Han Chinese. The PCR restriction fragment length polymorphism method was used for genotyping. Our data indicated that the MMP-9 -1562 C/T polymorphism was related with the risk of sepsis (CT vs. CC: P = 0.033, odds ratio (OR) = 1.45, 95% confidence interval (CI) 1.03–2.05; TT+CT vs. CC: P = 0.019, OR = 1.49, 95% CI 1.07–2.07). Stratified analyses demonstrated that this effect was more evident in smokers, drinkers, females and overweight individuals. Furthermore, cross-over analyses suggested that the combined effect of smoking and CT genotype of -1562 C/T polymorphism contributed to the risk of sepsis. In addition, MMP-9 serum levels were significantly lower in sepsis patients than in controls. The MMP-9 -1562 C/T polymorphism was significantly associated with decreased MMP-9 serum levels. Lastly, we observed that this polymorphism was connected to the mortality of sepsis. In conclusion, the interaction between the MMP-9 -1562 C/T polymorphism and smoking correlated with the risk of sepsis in Han Chinese. This polymorphism may serve as a diagnostic marker for sepsis patients.

Association of tumor necrosis factor-alpha -308 G/A and -238 G/A polymorphism with diabetic retinopathy: a systematic review and updated meta-analysis

BACKGROUND

Mounting evidence has suggested tumor necrosis factor-alpha (TNF-α) can promote the development of diabetic retinopathy (DR), and TNF-α gene variants may influence DR risk. However, the results are quite different.

OBJECTIVES

To comprehensively address this issue, we performed the meta-analysis to evaluate the association of TNF-α-308 G/A and -238 G/A polymorphism with DR.

METHOD

Data were retrieved in a systematic manner and analyzed using STATA Statistical Software. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of associations. Allelic and genotypic comparisons between cases and controls were evaluated.

RESULTS

For the TNF-α-308 G/A polymorphism, overall analysis suggested a marginal association with DR [the OR(95%CI) of (GA versus GG), (GA + AA) versus GG, and (A versus G) are 1.21(1.04, 1.41), 1.20(1.03, 1.39), and 1.14(1.01, 1.30), respectively]. And the subgroup analysis indicated an enhanced association among the European population. For the TNF-α-238 G/A polymorphism, there was mild correlation in the entire group [the OR(95%CI) of (GA versus GG) is 1.55(1.14,2.11) ], which was strengthened among the Asian population.

CONCLUSION

The meta-analysis suggested that -308 A and -238 A allele in TNF-α gene potentially increased DR risk and showed a discrepancy in different ethnicities.

Evaluation of TNF-α genetic polymorphisms as predictors for sepsis susceptibility and progression

Background

The goal of the study was to evaluate a potential role for tumor necrosis factor alpha (TNF-α) genetic variability as biomarker in sepsis. In particular, we aimed to determine if single nucleotide polymorphisms (SNPs) of TNF-α gene are associated with sepsis in terms of risk, severity and outcome.

Methods

We performed a prospective study on 163 adult critically ill septic patients (septic shock 65, sepsis 98, further divided in 40 survivors and 123 deceased) and 232 healthy controls. Genotyping of TNF-α SNPs (-308G/A, -238G/A, -376G/A and +489G/A) was performed for all patients and controls and plasma cytokine levels were measured during the first 24 h after sepsis onset.

Results

TNF-α +489G/A A-allele carriage was associated with significantly lower risk of developing sepsis and sepsis shock (AA+AG vs GG: OR = 0.53; p = 0.004; 95% CI = 0.34–0.82 and OR = 0.39; p = 0.003; 95% CI = 0.21–0.74, respectively) but not with sepsis-related outcomes. There was no significant association between any of the other TNF-α promoter SNPs, or their haplotype frequencies and sepsis or septic shock risk. Circulating TNF-α levels were higher in septic shock; they were not correlated with SNP genotype distribution; GG homozygosity for each polymorphism was correlated with higher TNF-α levels in septic shock.

Conclusions

TNF-α +489G/A SNP A-allele carriage may confer protection against sepsis and septic shock development but apparently does not influence sepsis-related mortality. Promoter TNF-α SNPs did not affect transcription and were not associated with distinct sepsis, septic shock risk or outcomes.

The association between the inflammatory response to surgery and postoperative complications in older patients with cancer; a prospective prognostic factor study

BACKGROUND

Accurate prognostic biomarkers would substantially improve surgical planning and decisions making yet no studies have been reported exploring the inflammatory response in surgically treated older patients with cancer. The aim of this study was to explore inflammatory biomarkers as potential prognostic factors for postoperative complications within 30 days in older patients with cancer.

METHOD

Patients 65 years and older undergoing surgery for removal of a solid malignant tumour were included in an observational cohort study. All complications occurring up to 30 days postoperatively were documented prospectively. Inflammatory markers were measured in plasma samples pre- and postoperatively: C-reactive protein (CRP), Interleukin-1 beta (IL-1β), IL-6, IL-10, IL-12, and Tumour necrosis factor-alpha (TNF-α). Associations between inflammatory markers and postoperative complications were explored using logistic regression analysis.

RESULTS

Between July 2010 and April 2014, plasma samples of 224 patients were collected. Median age was 72 (65-89) years and 116 (51.8%) patients were female. Approximately half of the patients developed postoperative complications (49.6%) of whom 62 patients (55.9%) developed >1 complication. An independent prognostic effect was observed for the inflammatory biomarkers IL-6 and IL-10 for the occurrence of postoperative complications.

CONCLUSION

The perioperative inflammatory response is associated with complications, independently from patient and surgical factors which are also associated with outcome. Research is warranted towards further exploration of the perioperative inflammatory response with the aim to improve perioperative care and outcome, and might help to improve surgical planning and decision making for older patients with cancer.

Single Nucleotide Polymorphisms and Post-operative Complications Following Major Gastrointestinal Surgery: a Systematic Review and Meta-analysis

BACKGROUND

The human genome is an under-researched area of pre-operative risk stratification. Studies of genetic polymorphisms and their associations with acute post-operative complications in gastrointestinal surgery have reported statistically significant results, but have varied in methodology, genetic variations studied, and conclusions reached. To provide clarity, we conducted a systematic review and meta-analysis of single nucleotide polymorphisms and their association with post-operative complications after major gastrointestinal surgery.

METHODS

We performed a literature search using Ovid MEDLINE and Web of Science databases. Studies were included if they investigated genetic polymorphisms and their associations with post-operative complications after major gastrointestinal surgery. We extracted clinical and genetic data from each paper and assessed for quality against the STrengthening the REporting of Genetic Association Studies (STREGA) guidelines. Odds ratios were presented, with 95% confidence intervals, to assess strengths of association. We conducted a meta-analysis on TNF-α-308, which had been assessed in three papers.

RESULTS

Our search returned 68 papers, of which 5 were included after screening and full-text review. Twenty-two different single nucleotide polymorphisms (SNPs) were investigated in these studies. We found that all papers were genetic association studies, and had selected SNPs related to inflammation. The outcome investigated was most commonly post-operative infection, but also anastomotic leak and other non-infectious complications. Statistically significant associations were found for TNF-α-308, IL-10-819, PTGS2-765 and IFN-γ-874. There was significant variability in study quality and methodology. We conducted a meta-analysis on associations between the TNF-α-308 polymorphism and post-operative infection and report an OR of 1.18 (CI 0.27-5.21).

CONCLUSIONS

We found biologically plausible associations between SNPs involved in inflammation and post-operative infection, but the available data were too limited and of insufficient quality to reach definitive conclusions. Further work is needed, including genome-wide association studies (GWAS).

The LPS Responsiveness in BN and LEW Rats and Its Severity Are Modulated by the Liver

Differences in LPS responsiveness influence the outcome of patients with sepsis. The intensity of the response is highly variable in patients and strain dependent in rodents. However, the role of the liver for initiating the LPS response remains ill defined. We hypothesize that hepatic LPS uptake is a key event for initiating the LPS response. In the present study, the severity of the LPS-induced inflammatory response and the hepatic LPS uptake was compared in two rat strains (Lewis (LEW) rats and Brown Norway (BN) rats). Using a transplantation model, we demonstrated the decisive role of the liver. The expression of hepatic TNF-α, IL-6, and IL-1β mRNA levels in BN rats was significantly lower than that in LEW rats. LEW rats were sensitized to LPS via G-CSF pretreatment. Sensitization caused by G-CSF pretreatment induced severe liver injury and mortality in LEW rats, but not in BN rats (survival rate: 0% (LEW) versus 100% (BN), p < 0.01). LEW rats presented with higher liver enzymes, more alterations in histology, and higher expression of caspase 3 and higher cytokines levels. One of the reasons could be the increased hepatic LPS uptake, which was only observed in LEW but not in BN livers. Using the transplantation model revealed the decisive role of the LPS responsiveness of the liver. Injection of LPS to the high-responding LEW recipient before transplantation of a low-responder BN liver resulted in a 50% survival rate. In contrast, injecting the same dose of LPS into the high-responding LEW recipient after transplanting the low-responding BN liver resulted in a 100% survival rate. The severity of inflammatory response in different strains might be related to the differences in hepatic LPS uptake. This observation suggests that the liver plays a genetically defined decisive role in modulating the inflammatory severity.

Sepsis and septic shock

Sepsis is a common condition that is associated with unacceptably high mortality and, for many of those who survive, long-term morbidity. Increased awareness of the condition resulting from ongoing campaigns and the evidence arising from research in the past 10 years have increased understanding of this problem among clinicians and lay people, and have led to improved outcomes. The World Health Assembly and WHO made sepsis a global health priority in 2017 and have adopted a resolution to improve the prevention, diagnosis, and management of sepsis. In 2016, a new definition of sepsis (Sepsis-3) was developed. Sepsis is now defined as infection with organ dysfunction. This definition codifies organ dysfunction using the Sequential Organ Failure Assessment score. Ongoing research aims to improve definition of patient populations to allow for individualised management strategies matched to a patient's molecular and biochemical profile. The search continues for improved diagnostic techniques that can facilitate this aim, and for a pharmacological agent that can improve outcomes by modifying the disease process. While waiting for this goal to be achieved, improved basic care driven by education and quality-improvement programmes offers the best hope of increasing favourable outcomes.

The effects of tumor necrosis factor-α (TNF-α) rs1800629 and rs361525 polymorphisms on sepsis risk

This meta-analysis of 23 eligible articles comprehensively and quantitatively evaluated the effects of tumor necrosis factor-α (TNF-α) rs1800629 and rs361525 polymorphisms on sepsis risk. We found that TNF-α rs1800629 was associated with increased sepsis risk in the overall population in four genetic models, including A vs. G (P<0.001, odds ratio (OR)=1.32), GA vs. GG (P<0.001, OR=1.46), GA+AA vs. GG (P<0.001, OR=1.46), and carrier A vs. carrier G (P<0.001, OR=1.32). Subgroup analyses showed a similar result for Asian patients (all P<0.05, OR>1). TNF-α rs361525 was also associated with increased sepsis risk in Asian patients in the four genetic models (all P<0.05, OR>1). Begg's and Egger's tests excluded large publication bias, and sensitivity analysis indicated stable results. Our results suggest that the G/A genotype of TNF-α rs1800629 and rs361525 increases sepsis risk in an Asian population.

Tumor necrosis factor-α -308G/A and -238G/A polymorphisms are associated with increased risks of sepsis: evidence from an updated meta-analysis

Previous studies have reported the relationship between tumor necrosis factor-α (TNF-α) -308G/A and -238G/A polymorphisms and sepsis risk with inconsistent results. The aim of this study was to estimate the association of the two polymorphisms with risk of sepsis or sepsis-related mortality using a meta-analysis. PubMed, Embase, and Web of Science databases were searched up to June 20 2016. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using fixed or random effect model. Twenty-six studies were included in this meta-analysis. Overall, an increased sepsis risk of TNF-α -308G/A was observed (GA vs GG: OR = 1.43, 95% CI: 1.07-1.92; GA/AA vs GG: OR = 1.42, 95% CI: 1.06-1.89). Subgroup analyses showed that the significant association was found in Asians (GA vs GG: OR = 1.63, 95% CI: 1.01-2.63) and adult patients. Similarly, an increased sepsis risk of TNF-α -238G/A was observed in overall and subgroup analyses. However, no significant association was found between TNF-α -308G/A and -238G/A polymorphisms and sepsis-related mortality. These findings indicate that both TNF-α -308G/A and -238G/A polymorphisms were associated with increased risks of sepsis but not sepsis-related mortality. Further studies with larger sample size are needed to confirm these results.

Association of tumor necrosis factor-α polymorphism with chemotherapy-induced oral mucositis in patients with esophageal cancer

The purpose of this study was to evaluate the association between tumor necrosis factor (TNF)-α polymorphisms and oral mucositis (OM) from 5-fluorouracil (5-FU) plus cisplatin (CDDP) chemotherapy for esophageal cancer. The rs1799964 polymorphism of TNF-α was genotyped using the tetra-primer amplification refractory mutation system polymerase chain reaction. The experimental group comprised 64 patients who received chemotherapy for esophageal cancer between 1997 and 2004; a total of 106 patients between 2005 and 2013 were investigated as the validation group. Univariate analysis of the experimental group revealed that the TT genotype of TNF-α rs1799964 was significantly higher in patients with grade 1-4 OM compared with the TC/CC genotypes [univariate odds ratio (OR)=4.0; P=0.029]. Similarly, univariate analysis of the validation group revealed that the percentage of the TT genotype was significantly higher in patients with grade 1-4 OM compared with the TC/CC genotypes (OR=2.8; P=0.043). This difference in risk was replicated in the validation cohort. Thus, the TT genotype of TNF-α rs1799964 may be a predictor of chemotherapy-induced OM in patients with esophageal cancer.

Predictive Genomics of Adverse Events After Cardiac Surgery

Significant, yet highly individual, thrombotic and inflammatory responses to surgery provide an excellent opportunity for insight into the genomic impact upon a patient's postoperative course. Cardiac surgery elicits the most profound perioperative disturbance and is associated with the highest incidence of adverse outcomes of any elective surgical procedure. Thus, cardiac surgical patients are an ideal population in which to evaluate the influence of complex traits on perioperative morbidity and mortality. This review describes the application of fundamental genetics upon the occurrence of adverse outcomes after cardiac surgery and cardiac transplantation. Specific emphases include a brief primer of the principles of genetics concentrating on the effects of variation within the human genome upon clinical outcomes and the differences between so-called Mendelian traits and complex traits. Four important clinical diseases dealt with in this review as examples of the impact of genetic factors on clinical outcomes are the genetics of heparin-induced thrombocytopenia, heart transplantation rejection and vasculopathy, atrial fibrillation, and infection.

Effect of Various Genetic Polymorphisms on the Incidence and Outcome of Severe Sepsis

Several genetic polymorphisms have been identified in patients with sepsis and severe sepsis, such as the tumor necrosis factor-α (TNF-α) and TNF-β genes, the interleukin-1 (IL-1) family, the IL-6, the IL-10, the CD-14, the Toll-like receptors, plasminogen activator inhibitor type 1, and the factor V 1691G-A mutations. In this study, the relationship between the TNF-α 308G/A, the IL-6-174 G/C, the PAI-1, the FVL, the EPCR, and the Cathepsin G (Ars 125 Ser) polymorphisms and the development and outcome of sepsis in pediatric patients was studied. TNF-α 308 G/A, PAI-1 4G/4G, and EPCR mutations influence the risk of severe sepsis in children. IL-6 174 G/C, FVL, and Cathepsin G (Ars 125 Ser) did not influence the incidence and mortality of severe sepsis.

Can biomarkers help us to better diagnose and manage sepsis?

The recognition over 25 years ago that the host response plays an exquisite role in sepsis, led to the today still-standard sepsis definition. Unfortunately, the inflammatory response syndrome (SIRS) criteria turned out to be less useful than anticipated, lacking sensitivity, specificity and ease of clinical application. Had novel host-response biomarkers been available by that time, it arguably would have been preferable to white blood cell count as an unspecific and not-sensitive laboratory-based SIRS criterion. Several novel markers have been put forward as sepsis markers with better diagnostic and/or prognostic potential in sepsis including inflammatory markers such as procalcitonin (PCT), presepsin, proadrenomedullin (ProADM), endothelial dysfunction markers such as P-selectin, E-selectin, intercellular cell adhesion molecule [ICAM]-1 and vascular cell adhesion molecule [VCAM]-1 and genetic markers among others. The limitations to using clinical parameters and conventional diagnostic markers for patients with clinical suspicion of sepsis may directly lead to both, under treatment of patients with severe disease needing urgent antibiotic and fluid therapy, and unnecessary and prolonged exposure to antimicrobial agents adversely affecting patient outcomes and increasing antibiotic resistance. The aim of this review is to summarize the current evidence for emerging diagnostic, prognostic, and therapeutic-response sepsis biomarkers in different infections and clinical settings, and discuss the reliability, potential benefit and limitations of these marker when used in clinical routine for sepsis management.

TNF-α, IL-6, and IL-8 cytokines and their association with TNF-α-308 G/A polymorphism and postoperative sepsis

INTRODUCTION

Early prediction of postoperative sepsis remains an enormous clinical challenge. Association of TNF-α-308 G/A polymorphism with sepsis remains controversial. We, therefore, investigated this polymorphism with serum levels of cytokines TNF-α, IL-6, and IL-8 in relation to development of sepsis following major gastrointestinal surgery.

METHODS

Two hundred and thirty-nine patients undergoing major gastrointestinal surgery were enrolled. Polymorphism was studied through the analysis of restriction fragments of Nco1-digested DNA with the polymerase chain reaction. All patients were followed for 1 month following surgery for evidence of sepsis. Levels of serum cytokines TNF-α, IL-6, and IL-8 were measured preoperatively and postoperatively by enzyme-linked immunosorbent assay (ELISA).

RESULTS

Forty-seven (19.66 %) patients developed postoperative sepsis. Patients with postoperative sepsis were significantly (p = 0.002) more likely to possess AA homozygous genotype with higher capacity to produce cytokines TNF-α (p < 0.0001), IL-6 (p < 0.0001), and IL-8 (p < 0.0001) as compared to other genotypes. When compared with patients carrying at least one G allele, the AA genotype was associated with a significantly higher probability (odds ratio (OR) = 4.17; p = 0.003; 95 % confidence interval (CI) = 1.5-11.48) of developing sepsis. Compared with the GG genotype, AA was associated with a significantly higher probability (OR = 5.18; p = 0.0008; 95 % CI = 1.82-14.76) of sepsis development.

CONCLUSION

TNF-α-308 G/A polymorphism is significantly associated with the development of postoperative sepsis and with increased expression of cytokines TNF-α, IL-6, and IL-8.

The beginning of personalized medicine in sepsis: small steps to a bright future

There is a growing recognition that there is a need for a more personalized approach towards sepsis care. In most clinical trials investigating novel therapeutic interventions against sepsis, patients have been considered a rather homogeneous population. However, there is probably more individual variability between septic patients than previously considered. The pathophysiology of sepsis is a complex and dynamic process that originates from the host immune response to infection and varies according to the genetic predisposition, immune status and co-morbid conditions of the host, the type of pathogen and the site and extent of infection. Until now, efforts to stratify septic patients according to their immune profile were hampered by the lack of specific biomarkers. Recent advances in molecular medicine have made it possible to develop tools that will facilitate a faster and more precise diagnosis of infection. Individual variability between each patient's responses to infection can assist in tailoring therapeutic interventions to the individual's disease profile and monitoring treatment response. In this review, we describe those recent advances in genomics and theragnostics, which are slowly entering clinical practice and which will make possible a more personalized approach to each septic patient in the next decade.

Bench-to-bedside review: future novel diagnostics for sepsis - a systems biology approach

The early, accurate diagnosis and risk stratification of sepsis remains an important challenge in the critically ill. Since traditional biomarker strategies have not yielded a gold standard marker for sepsis, focus is shifting towards novel strategies that improve assessment capabilities. The combination of technological advancements and information generated through the human genome project positions systems biology at the forefront of biomarker discovery. While previously available, developments in the technologies focusing on DNA, gene expression, gene regulatory mechanisms, protein and metabolite discovery have made these tools more feasible to implement and less costly, and they have taken on an enhanced capacity such that they are ripe for utilization as tools to advance our knowledge and clinical research. Medicine is in a genome-level era that can leverage the assessment of thousands of molecular signals beyond simply measuring selected circulating proteins. Genomics is the study of the entire complement of genetic material of an individual. Epigenetics is the regulation of gene activity by reversible modifications of the DNA. Transcriptomics is the quantification of the relative levels of messenger RNA for a large number of genes in specific cells or tissues to measure differences in the expression levels of different genes, and the utilization of patterns of differential gene expression to characterize different biological states of a tissue. Proteomics is the large-scale study of proteins. Metabolomics is the study of the small molecule profiles that are the terminal downstream products of the genome and consists of the total complement of all low-molecular-weight molecules that cellular processes leave behind. Taken together, these individual fields of study may be linked during a systems biology approach. There remains a valuable opportunity to deploy these technologies further in human research. The techniques described in this paper not only have the potential to increase the spectrum of diagnostic and prognostic biomarkers in sepsis, but they may also enable the discovery of new disease pathways. This may in turn lead us to improved therapeutic targets. The objective of this paper is to provide an overview and basic framework for clinicians and clinical researchers to better understand the 'omics technologies' to enhance further use of these valuable tools.

Tumor necrosis factor alpha promoter polymorphism and severity of acute kidney injury

BACKGROUND

Tumor necrosis factor-alpha is a proinflammatory cytokine that has been implicated in the pathobiology of acute kidney injury (AKI).

METHODS

We explored the association of a functional polymorphism in the promoter region (rs1800629) of the TNFA gene with severity of AKI, as defined by level of glomerular filtration (serum cystatin C and creatinine) and tubular injury (urinary NAG, KIM-1, α-GST, and π-GST) markers, in 262 hospitalized adults.

RESULTS

In unadjusted analyses, compared with the GG genotype, the TNFA GA and AA genotype groups tended to have higher enrollment (p = 0.08), peak (p = 0.004), and discharge (p = 0.004) serum creatinine levels, and the AA genotype tended to have a higher enrollment serum cystatin C level (p = 0.04). Compared with the GG genotype, the TNFA GA and AA genotype groups tended to have a higher urinary KIM-1 level (p = 0.03), and the AA genotype group tended to have a higher urinary π-GST level (p = 0.03). After adjustment for sex, race, age, baseline estimated glomerular filtration rate, sepsis, and dialysis requirement, compared with the GG genotype, the TNFA minor A-allele group had a higher peak serum creatinine of 1.03 mg/dl (0.43, 1.63; p = 0.001) and a higher urinary KIM-1 (relative ratio: 1.73; 95% CI: 1.16, 2.59; p = 0.008). The TNFA minor A-allele group also had a higher Multiple Organ Failure score of 0.26 (95% CI: 0.03, 0.49; p = 0.024) after adjustment for sex, race, age, and sepsis.

CONCLUSIONS

The TNFA rs1800629 gene polymorphism is associated with markers of kidney disease severity and distant organ dysfunction among patients with AKI. Larger studies are needed to confirm these relationships.

Genetic variation in the TNF gene is associated with susceptibility to severe sepsis, but not with mortality

Background

Tumor necrosis factor (TNF) and TNF receptor superfamily (TNFR)-mediated immune response play an essential role in the pathogenesis of severe sepsis. Studies examining associations of TNF and lymphotoxin-α (LTA) single nucleotide polymorphisms (SNPs) with severe sepsis have produced conflicting results. The objective of this study was to investigate whether genetic variation in TNF, LTA, TNFRSF1A and TNFRSF1B was associated with susceptibility to or death from severe sepsis in Chinese Han population.

Methodology/Principal Findings

Ten SNPs in TNF, LTA, TNFRSF1A and TNFRSF1B were genotyped in samples of patients with severe sepsis (n = 432), sepsis (n = 384) and healthy controls (n = 624). Our results showed that rs1800629, a SNP in the promoter region of TNF, was significantly associated with risk for severe sepsis. The minor allele frequency of rs1800629 was significantly higher in severe sepsis patients than that in both healthy controls (P_adj = 0.00046, odds ratio (OR)_adj = 1.92) and sepsis patients (P_adj = 0.002, OR_adj = 1.56). Further, we investigated the correlation between rs1800629 genotypes and TNF-α concentrations in peripheral blood mononuclear cells (PBMCs) of healthy volunteers exposed to lipopolysaccharides (LPS) ex vivo, and the association between rs1800629 and TNF-α serum levels in severe sepsis patients. After exposure to LPS, the TNF-α concentration in culture supernatants of PBMCs was significantly higher in the subjects with AA+AG genotypes than that with GG genotype (P = 0.007). Moreover, in patients with severe sepsis, individuals with AA+AG genotypes had significantly higher TNF-α serum concentrations than those with GG genotype (P_adj = 0.02). However, there were no significant associations between SNPs in the four candidate genes and 30 day mortality for patients with severe sepsis.

Conclusions/Significance

Our findings suggested that the functional TNF gene SNP rs1800629 was strongly associated with susceptibility to severe sepsis, but not with lethality in Chinese Han population.

Does clinically relevant temperature change miRNA and cytokine expression in whole blood?

Unintentional hypothermia is a well-described risk factor for death and complications after elective and emergency surgery. The molecular mechanisms by which hypothermia exerts its detrimental effects are not well understood. Differences in cytokine production and the overall cell function have been reported under hypothermic conditions. We investigated the effect of a range of clinically relevant temperatures on cytokine production and microRNA (miRNA) expression in a whole-blood model. We found that there was a wide variation in tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and IL-10 production among different subjects, ranging from low to high TNF-α producers. The intersubject variation can also be found on the transcriptional level: high producers had higher upregulation of TNF-α messenger RNA than intermediate and low producers. This variation in TNF-α was reproducible in each individual. Temperature seems to modulate TNF-α production among these different groups. miRNA expression was modulated by temperature. miRNA-181a might control, or be a part of the mechanism which controls, TNF-α production. However, an analysis of whole-leukocyte RNA does not allow the investigation of mechanisms in a specific leukocyte subpopulation such as monocytes, because these changes may be concealed by miRNA expression changes in the other leukocyte subsets. In conclusion, TNF-α, IL-6, and IL-10 production is highly variable among different persons, but temperature affects the expression of miRNAs, which may consequently alter the production of TNF-α.

Genetic polymorphisms within tumor necrosis factor gene promoter region: a role for susceptibility to ventilator-associated pneumonia

Debatable findings exist among various studies regarding the impact of single nucleotide polymorphisms (SNPs) within the promoter region of the tumor necrosis factor (TNF) gene for susceptibility to infections. Their impact was investigated in a cohort of mechanically ventilated patients who developed ventilator-associated pneumonia (VAP). Two-hundred and thirteen mechanically ventilated patients who developed VAP were enrolled. Genomic DNA was extracted and SNPs at the -376, -308 and -238 position of the promoter region of the TNF gene were assessed by restriction fragment length polymorphisms. Monocytes were isolated from 47 patients when they developed sepsis and stimulated by bacterial endotoxin for the production of TNFα and of interleukin-6 (IL-6). Patients were divided into two groups; 166 patients bearing only wild-type alleles of all three studied polymorphisms; and 47 patients carrying at least one A allele of the three studied SNPs. Time between start of mechanical ventilation and advent of VAP was significantly shorter in the second group than in the first group (log-rank: 4.416, p: 0.041). When VAP supervened, disease severity did not differ between groups. Stimulation of TNFα and of IL-6 was much greater by monocytes for patients carrying A alleles. Carriage of at least one A allele of the three studied SNPs at the promoter region of the TNF-gene is associated with shorter time to development of VAP but it is not associated with disease severity. Findings may be related with a role of the studied SNPs in the production of pro-inflammatory cytokines.

Bench-to-bedside review: Neonatal sepsis-redox processes in pathogenesis

The present review is aimed at elucidating the neonatal 'sepsis redox cycle' - the cascade of inflammatory and redox events involved in the pathogenesis of sepsis in neonates. While adult and neonatal sepses share some common features, there are some substantial differences: higher mortality rates occur in adult sepsis and worse long-term effects are evident in neonatal sepsis survivors. Such epidemiological data may be explained by the lower ability of IL6 and IL8 to activate NF-κB-regulated transcription in neonatal sepsis in comparison to TNF-α, which is involved in the mechanisms of adult sepsis. The activation of NF-κB in neonatal sepsis is further promoted by hydrogen peroxide and results in mitochondrial dysfunction and energy failure as septic neonates experience decreased O₂ consumption as well as lower heat production and body temperature in comparison to healthy peers. In neonates, specific organs that are still under development are vulnerable to sepsis-provoked stress, which may lead to brain, lung, and heart injury, as well as vision and hearing impairments. In the light of the processes integrated here, it is clear that therapeutic approaches should also target specific steps in the neonatal 'sepsis redox cycle' in addition to the current therapeutic approach that is mainly focused on pathogen eradication.

Bench-to-bedside review: sepsis - from the redox point of view

The pathogenesis of sepsis and its progression to multiple organ dysfunction syndrome and septic shock have been the subject of investigations for nearly half a century. Controversies still exist with regard to understanding the molecular pathophysiology of sepsis in relation to the complex roles played by reactive oxygen species, nitric oxide, complements and cytokines. In the present review we categorise the key turning points in sepsis development and outline the most probable sequence of events leading to cellular dysfunction and organ failure under septic conditions. We have applied an integrative approach in order to fuse current state-of-the-art knowledge about redox processes involving hydrogen peroxide, nitric oxide, superoxide, peroxynitrite and hydroxyl radical, which lead to mitochondrial respiratory dysfunction. Finally, from this point of view, the potential of redox therapy targeting sepsis is discussed.

Pharmacogenetics: implications for therapy in rheumatic diseases

DMARDs not only improve the joint pain and swelling associated with rheumatoid arthritis (RA), but also slow down the joint damage associated with the disease. The efficacy of biologic therapies, introduced in the past decade for the treatment of RA, has been unequivocally established. Similarly, in addition to traditional drugs such as hydroxychloroquine, new biologic agents such as rituximab have been introduced for systemic lupus erythematosus in recent years. However, considerable variability occurs in the responses of patients to these therapies. Pharmacogenetics, the study of variations in genes encoding drug transporters, drug-metabolizing enzymes and drug targets, and their translation to differential responses to drugs, is a rapidly progressing field in rheumatology. Pharmacogenetic applications, particularly to the old vanguard DMARD, methotrexate, and the newer, more expensive biologic agents, might make personalized therapy in rheumatic diseases possible. The pharmacogenetics of commonly used DMARDs and of biologic therapies are described in this Review.

Tumor necrosis factor alpha gene polymorphism is associated with the outcome of trauma patients in Chinese Han population

BACKGROUND

Tumor necrosis factor (TNF) is a proinflammatory cytokine that plays a major role in the sepsis and multiple organ dysfunction secondary to major trauma. The purpose of this article was to research the clinical relevance of the TNF gene polymorphism in patients with major trauma.

METHODS

Three hundred six patients with major trauma were prospectively recruited. The TNF gene polymorphisms were genotyped using restriction fragment length polymorphism analysis. Plasma TNF-α levels were determined with enzyme-linked immunosorbent assay. Sepsis morbidity rate and multiple organ dysfunction scores were accessed.

RESULTS

The TNF-α/-308 polymorphism was shown to be well associated with increased capacity of peripheral leukocytes to produce TNF-α in response to ex vivo lipopolysaccharide stimulation in trauma patients at admission. Results from association study indicated that trauma patients carrying the TNF-α/-308/A allele were more likely complicated with sepsis.

CONCLUSIONS

The TNF-α/-308 polymorphism might be used as a biomarker for the assessment of outcome of trauma patients, but the TNF-β/252 gene polymorphism might not influence the development of complications in patients with major trauma.

Leprosy and the human genome

Despite the availability of effective treatment for several decades, leprosy remains an important medical problem in many regions of the world. Infection with Mycobacterium leprae can produce paucibacillary disease, characterized by well-formed granulomas and a Th1 T-cell response, or multibacillary disease, characterized by poorly organized cellular infiltrates and Th2 cytokines. These diametric immune responses confer states of relative resistance or susceptibility to leprosy, respectively, and have well-defined clinical manifestations. As a result, leprosy provides a unique opportunity to dissect the genetic basis of human in vivo immunity. A series of studies over the past 40 years suggests that host genes influence the risk of leprosy acquisition and the predilection for different clinical forms of the disease. However, a comprehensive, cellular, and molecular view of the genes and variants involved is still being assembled. In this article, we review several decades of human genetic studies of leprosy, including a number of recent investigations. We emphasize genetic analyses that are validated by the replication of the same phenotype in independent studies or supported by functional experiments demonstrating biological mechanisms of action for specific polymorphisms. Identifying and functionally exploring the genetic and immunological factors that underlie human susceptibility to leprosy have yielded important insights into M. leprae pathogenesis and are likely to advance our understanding of the immune response to other pathogenic mycobacteria. This knowledge may inform new treatment or vaccine strategies for leprosy or tuberculosis.

Genomics of Acute Lung Injury and Vascular Barrier Dysfunction

Acute lung injury (ALI) is a devastating ­syndrome of diffuse alveolar damage that develops via a variety of local and systemic insults such as sepsis, trauma, ­pneumonia, and aspiration. It is interestingly to note that only a subset of individuals exposed to potential ALI-inciting insults develop the disorder and the severity of the disease varies from complete resolution to death. In addition, ALI susceptibility and severity are also affected by ethnicity as evidenced by the higher mortality rates observed in African-American ALI patients compared with other ethnic groups in the USA. Moreover, marked differences in strain-specific ALI responses to inflammatory and injurious agents are observed in preclinical animal models. Together, these observations strongly indicate genetic components to be involved in the pathogenesis of ALI. The identification of genes contributing to ALI would potentially provide a better understanding of ALI pathobiology, yield novel biomarkers, identify individuals or populations at risk, and prove useful for the development of novel and individualized therapies. Genome-wide searches in animal models have identified a number of quantitative trait loci that associate with ALI susceptibility. In this chapter, we utilize a systems biology approach combining cellular signaling pathway analysis with population- based association studies to review established and suspected candidate genes that contribute to dysfunction of endothelial cell barrier integrity and ALI susceptibility.

Ethical considerations in the collection of genetic data from critically ill patients: what do published studies reveal about potential directions for empirical ethics research?

Critical illness trials involving genetic data collection are increasingly commonplace and pose challenges not encountered in less acute settings, related in part to the precipitous, severe and incapacitating nature of the diseases involved. We performed a systematic literature review to understand the nature of such studies conducted to date, and to consider, from an ethical perspective, potential barriers to future investigations. We identified 79 trials enrolling 24 499 subjects. Median (interquartile range) number of participants per study was 263 (116.75-430.75). Of these individuals, 16 269 (66.4%) were Caucasian, 1327 (5.4%) were African American, 1707 (7.0%) were Asian Pacific Islanders and 139 (0.6%) were Latino. For 5020 participants (20.5%), ethnicity was not reported. Forty-eight studies (60.8%) recruited subjects from single centers and all studies examined a relatively small number of genetic markers. Technological advances have rendered it feasible to conduct clinical studies using high-density genome-wide scanning. It will be necessary for future critical illness trials using these approaches to be of greater scope and complexity than those so far reported. Empirical research into issues related to greater ethnic inclusivity, accuracy of substituted judgment and specimen stewardship may be essential for enabling the conduct of such trials.

Tumor necrosis factor alpha gene variants do not display allelic imbalance in circulating myeloid cells

Carriage of the TNF -308 A allele (rs1800629 A) has been associated with increased serum TNF-alpha levels, the development of sepsis syndrome, and fatal outcome, in severely traumatized patients (Menges et al., 2008 [1]). Herein, we analysed the putative allelic imbalance of TNF-alpha release from myeloid cells. Circulating peripheral blood cells from healthy human blood donors (n=104) and monocyte-derived macrophages (n=158) were analysed for their ex vivo capacity of TNF-alpha expression. Our findings indicate that carriage of the TNF -308 A allele is not associated with high TNF-alpha expression in circulating human leucocytes and monocyte-derived macrophages. Other cellular sources, e.g. tissue-resident cells like mast cells and/or tissue specific macrophages might be the cellular source of high TNF-alpha serum levels shortly after trauma.

Polymorphisms of genes encoding tumor necrosis factor-alpha, interleukin-10, cluster of differentiation-14 and interleukin-1ra in critically ill patients

PURPOSE

The aim of the study was to determine whether distributions of tumor necrosis factor (TNF)-α(308), interleukin (IL)-10(1082), CD14(159), and IL-1ra gene intron 2 genotypes in critically ill patients are associated with outcome, underlying cause of sepsis, and type of microorganism.

MATERIALS AND METHODS

Blood samples from 106 critically ill white patients were genotyped by method based on polymerase chain reaction for TNF-α(308), IL-10(1082), CD14(159), and IL-1ra gene intron 2.

RESULTS

All patients with TNF-α(308)AA genotype survived; relative risk (RR) of death in patients with AG was 3.250 and with GG, 1.923 (P < .01). In patients with Gram-positive sepsis, IL-10(1082)AA and then AG genotypes were the most frequent ones (odds ratio [OR], 18.67 and 7.20, respectively; P < .01). When comparing IL-10(1082)AA with AG, RR of pancreatitis was 1.80 and OR was 3.40. When AA and GG were compared, RR was 7.33 and OR was 20.00. In patients with GG, RR of peritonitis was 4.07 and OR was 5.88 (P < .01). In patients with Gram-positive sepsis, CD14(159)CT was the most frequent one with OR of 5.25. Distribution of 6 IL-1ra gene intron 2 genotypes showed no significant association.

CONCLUSIONS

Distribution of TNF-α(308) genotypes is associated with outcome, IL-10(1082) with type of microorganism and underlying cause of sepsis, and CD14(159) with type of microorganism.

Association between tumor necrosis factor alpha 308G/A polymorphism and increased proinflammatory cytokine release after cardiac surgery with cardiopulmonary bypass in the Korean population

OBJECTIVES

The G-308A polymorphism of the tumor necrosis factor alpha (TNF-alpha) gene has been suggested to be linked to high TNF promoter activity in in vitro studies. However, there have been some controversies in in vivo studies. This study investigated whether A allele at TNF-308 site is associated with (1) the changes in plasma cytokine levels during and after cardiopulmonary bypass (CPB) and (2) an increased incidence of pulmonary morbidity after CPB.

DESIGN

Prospective and observational investigation.

SETTING

A university hospital, single institution.

PARTICIPANTS

Patients scheduled for cardiac surgery with CPB.

INTERVENTION

TNF genotype was determined by the real-time polymerase chain reaction method. IL-6 and TNF-alpha levels were measured by enzyme-linked immunosorbent assay at the following time points: T1, before initiation of CPB; T2, 30 minutes of CPB; T3, 30 minutes after CPB; T4, 2 hours after CPB; and T5, 24 hours after CPB. The oxygen index, serum creatinine level, 24-hour blood loss, intubation time, and length of intensive care unit (ICU) stay were examined.

MEASUREMENTS AND MAIN RESULTS

The levels of TNF-alpha in group A (TNF-308GA/AA, n = 25) were higher at T3, T4, and T5 than group G (TNF-308GG, n = 225). The levels of IL-6 showed no statistical difference. The oxygenation index, serum creatinine level, 24-hour blood loss, intubation time, and length of ICU stay showed no statistical difference.

CONCLUSIONS

TNF G-308A polymorphism may be associated with excess TNF-alpha secretion in this study and may not be associated with excess IL-6 secretion and postoperative morbidity after CPB.

Genetic polymorphisms of the lymphotoxin alpha gene are associated with increased risk for lethal infections during induction therapy for childhood acute leukemia: a case-control study

Specific mutations of the TNF-alpha (TNF-α) and Lymphotoxin-alpha (LT-α) genes are correlated to the outcome of patients during serious infections. This study aimed at correlating these polymorphisms to lethal infections during childhood acute lymphoblastic leukemia (ALL). A matched case-control study of 34 patients who died due to infections during ALL treatment and 68 ALL patients without lethal infections was performed. Genomic DNA was isolated from blood smears and specific fragments including the polymorphic site of each gene were amplified. In the total study population, 23/102 (22.5%) of the children carried at least two variant alleles (high-producer haplotype). The variant genotypes were equally distributed between cases and controls [relative risk (RR) 1.17 (CI 0.33–2.22, P = 0.752)]. With regard to infective organisms, no statistically significant differences could be detected between the groups for bacterial infections [RR 1.59 (CI 0.56–4.50), P 0.379]. Patients with a LT-α (10.5 kb/5.5 kb; 5.5 kb/5.5 kb) haplotype, however, seemed to have a significant higher risk of attracting a lethal infection during induction/consolidation chemotherapy (RR 2.98, CI 0.98–9.01, P = 0.05). These results support a role of specific genetic polymorphisms on lethal infections during induction chemotherapy of ALL treatment.

Future diagnostic and therapeutic approaches in surgical infections

Despite ongoing efforts to standardize therapy and improve management, the morbidity and mortality associated with surgical infections remain high. Continued innovation is required to improve outcomes further, particularly in the face of the increasing prevalence of multidrug resistant organisms. Although they remain in the experimental stages, a number of recent advances have the potential to have significant impact on the management and outcomes of surgical infections. These include novel diagnostic strategies, antimicrobials targeting microbial virulence factors, novel vaccines, and risk stratification based on genetic profiling.

Tumor necrosis factor gene variation and the risk of mortality after burn injury: a cohort study

Infection risk and mortality after burn trauma are primarily determined by patient age, burn size and depth, and associated inhalation injury. Whether genetic differences contribute to otherwise unexpected variability in outcomes is unknown. We sought to determine whether there was an association between genetic variation in inflammation-related genes and outcomes after burn trauma. We evaluated patients with burns >or=15% TBSA at a single regional burn center from October 2003 to December 2005. Blood was collected on admission and DNA genotyping was performed. We genotyped single nucleotide polymorphism (SNPs) in toll-like receptor 4 (TLR4) A896G, tumor necrosis factor alpha (TNF-alpha) G-308A, Interleukin-6 (IL-6) G-174C, interleukin-1beta (IL-1beta) T-31C, and cluster of differentiation marker 14 (CD14) C-159T. We compared SNP genotypes between survivors and nonsurvivors by chi analysis and logistic regression. Sixty-nine subjects with a median age of 38 years and mean TBSA of 34% were enrolled. The case fatality was 17%. Septic shock developed in 7 (10%) patients. After adjustment for age, percent full-thickness burns, and inhalation injury, carriage of the TNF-alpha -308 variant allele was associated with increased risk of mortality (OR 10.7, 95% CI = 1.2-95.5, P = .034). None of the other SNPs evaluated were associated with mortality. Mortality after burn trauma is primarily determined by clinical factors, but the TNF-alpha -308 A allele seems to contribute to an increased mortality risk.

Multiple organ dysfunction syndrome in children with sepsis: role of genetic factors

This review summarizes current knowledge on the impact of genetic markers on susceptibility, severity, and outcome of acute inflammatory disorders in children, with a special focus on systemic infections. A 14-year-old child with Neisseria meningitides bacteremia, complicated by septic shock and multiple organ dysfunction, is discussed as an exemplary case, and linked to the application of genetic epidemiology and the study of common disorders in children. The current pertinent literature is comprehensively reviewed and limitations and future directions are discussed.

Genetic influence on bloodstream infections and sepsis

Bloodstream infections (BSIs) are a major burden in health care today, associated with considerable morbidity, mortality and costs. They are either caused by direct influx of pathogens via devices into the blood (primary BSI) or by bacterial spillover from infected distant organs (secondary BSI). The recognition of invading microbes by sensing of conserved molecular patterns is pivotal for the host in staging an adequate immune response to eradicate the pathogen. Moreover, a balanced immune response is crucial to avoid over inflammation followed by additional damage to the host. This complex host response pattern is controlled by soluble proteins and cellular receptors, which have recently been found to contain substantial individual genetic variations. Single nucleotide polymorphisms have been shown to affect susceptibility to and the course of numerous diseases. A large number of genes and their products are involved in the host reaction to BSIs, and genetic variation in these molecules alters the frequency and course of these events. Here we summarise recent findings on genetic variations in molecules of the innate immune system and other systems as well as their connection with susceptibility to BSIs and sepsis and the way the host stages a beneficial response to infection.

Characterization of tumour necrosis factor-alpha genetic variants and mRNA expression in patients with severe sepsis

Tumour necrosis factor-alpha (TNFalpha) has been implicated in the pathogenicity of severe sepsis by both genetic association studies and animal models. Conflicting functional data have emerged in relation to genetic variants and TNFalpha protein production. Therefore, we assessed the functionality of TNFalpha genetic variants in terms of mRNA production and their potential influence on outcome in the setting of severe sepsis. Sixty-two Irish Caucasian patients presenting with severe sepsis were recruited and TNFalpha mRNA and protein levels were quantified. Patient DNA was analysed for the presence of common promoter polymorphisms and haplotypes were inferred. An A allele at position -863 was associated with more TNFalpha mRNA on day 1 compared to C homozygotes (P = 0.037). There was a trend for G homozygotes at position -308 to produce more TNFalpha mRNA on day 1 than those carrying an A allele (P = 0.059). The presence of an A allele at -863 was associated with greater levels of TNFalpha mRNA in comparison with patients carrying the A allele at -308 on day 1 (P = 0.02). Patients homozygous for the A allele at position -308 had a higher mortality than those carrying the G allele (P = 0.01). Our data are consistent with recent reports suggesting that a deficient proinflammatory response may be harmful in human sepsis. This deficient inflammatory response may be mediated in part by polymorphisms in the TNFalpha promoter.

Inflammation and genomics in the critical care unit

Inflammation is a physiologic response to irritants, injury, and infection. Inflammatory dysregulation is believed to contribute to mortality and morbidity in illnesses common to critical care units, such as burns, trauma, sepsis, and cardiovascular disease. This article reviews the approaches used to investigate the molecular basis of inflammatory function. Genomic findings are providing insight into clinical diagnosis and treatment of inflammatory derangements in critically ill patients.

Zinc-gene interaction related to inflammatory/immune response in ageing

The pivotal role played by zinc-gene interaction in affecting some relevant cytokines (IL-6 and TNF-alpha) and heat shock proteins (HSP70-2) in ageing, successful ageing (nonagenarians) and the most common age-related diseases, such as atherosclerosis and infections, is now recognized. The polymorphisms of genes codifying proteins related to the inflammation are predictive on one hand in longevity, on the other hand they are associated with atherosclerosis or severe infections. Since the health life-span has a strong genetic component, which in turn also affected by nutritional factors like zinc, the association of these polymorphisms with innate immune response, zinc ion bioavailability and Metallothioneins (MT) homeostasis is an useful tool to unravel the role played by zinc-gene interactions in longevity, especially due to the inability of MT in zinc release in ageing and chronic inflammation. In ageing, this last fact leads to depressed innate immune response for host defence. In contrast, in very old age the inflammation is lower with subsequent more zinc ion bioavailability, less MT gene expression and satisfactory innate immunity. Therefore, the zinc-gene (IL-6, TNF-alpha, Hsp70-2) interactions, via MT homeostasis, are crucial to achieve successful ageing.