Endotoxemia and acute-phase proteins in major abdominal surgery

Extrahepatic Surgery in Cirrhosis Significantly Increases Portal Pressure in Preclinical Animal Models

Background: Liver cirrhosis is a relevant comorbidity with increasing prevalence. Postoperative decompensation and development of complications in patients with cirrhosis remains a frequent clinical problem. Surgery has been discussed as a precipitating event for decompensation and complications of cirrhosis, but the underlying pathomechanisms are still obscure. The aim of this study was to analyze the role of abdominal extrahepatic surgery in cirrhosis on portal pressure and fibrosis in a preclinical model.

Methods: Compensated liver cirrhosis was induced using tetrachlormethane (CCL4) inhalation and bile duct ligation (BDL) models in rats, non-cirrhotic portal hypertension by partial portal vein ligation (PPVL). Intestinal manipulation (IM) as a model of extrahepatic abdominal surgery was performed. 2 and 7 days after IM, portal pressure was measured in-vivo. Hydroxyproline measurements, Sirius Red staining and qPCR measurements of the liver were performed for evaluation of fibrosis development and hepatic inflammation. Laboratory parameters of liver function in serum were analyzed.

Results: Portal pressure was significantly elevated 2 and 7 days after IM in both models of cirrhosis. In the non-cirrhotic model the trend was the same, while not statistically significant. In both cirrhotic models, IM shows strong effects of decompensation, with significant weight loss, elevation of liver enzymes and hypoalbuminemia. 7 days after IM in the BDL group, Sirius red staining and hydroxyproline levels showed significant progression of fibrosis and significantly elevated mRNA levels of hepatic inflammation compared to the respective control group. A progression of fibrosis was not observed in the CCL4 model.

Conclusion: In animal models of cirrhosis with continuous liver injury (BDL), IM increases portal pressure, and development of fibrosis. Perioperative portal pressure and hence inflammation processes may be therapeutic targets to prevent post-operative decompensation in cirrhosis.

Surgery for Colorectal Cancer: A Trigger for Liver Metastases Development? New Insights into the Underlying Mechanisms

Surgery is a crucial intervention and provides the best chance of cure for patients with colorectal cancer. Experimental and clinical evidence, however, suggests that paradoxically surgery itself may precipitate or accelerate tumor recurrence and/or liver metastasis development. This review addresses the various aspects of surgery-induced metastasis formation and sheds light on the role of inflammation as potential trigger for metastasis development. Understanding these mechanisms may provide potential new perioperative interventions to improve treatment outcomes, and as such could transform the perioperative timeframe from a facilitator of metastatic progression to a window of opportunity to reduce the risk of liver metastasis development. Ultimately, this can potentially improve long-term survival rates and quality of life in patients with colorectal cancer.

Macrophages mediate colon carcinoma cell adhesion in the rat liver after exposure to lipopolysaccharide

The surgical resection of primary colorectal cancer is associated with an enhanced risk of liver metastases. Moreover, bacterial translocation or anastomic leakage during resection has been shown to correlate with a poor long-term surgical outcome, suggesting that bacterial products may contribute to the formation of metastases. Driven by these premises, we investigated the role of the bacterial product lipopolysaccharide (LPS) in the generation of liver metastases. Intraperitoneal injection of LPS led to enhanced tumor-cell adhesion to the rat liver as early as 1.5 h post-administration. Furthermore, a rapid loss of the expression of the tight junction protein zonula occludens-1 (ZO-1) was observed, suggesting that LPS disrupts the integrity of the microvasculature. LPS addition to endothelial-macrophage co-cultures damaged endothelial monolayers and caused the formation of intercellular gaps, which was accompanied by increased tumor-cell adhesion. These results suggest that macrophages are involved in the endothelial damage resulting from exposure to LPS. Interestingly, the expression levels of of ZO-1 were not affected by LPS treatment in rats in which liver macrophages had been depleted as well as in rats that had been treated with a reactive oxygen species (ROS) scavenger. In both settings, decreased tumor-cell adhesion was observed. Taken together, our findings indicate that LPS induces ROS release by macrophages, resulting in the damage of the vascular lining of the liver and hence allowing increased tumor-cell adherence. Thus, peri-operative treatments that prevent the activation of macrophages and—as a consequence—limit endothelial damage and tumor-cell adhesion may significantly improve the long-term outcome of cancer patients undergoing surgical tumor resection.

Effects of perioperative intravenous ω-3 fatty acids in colon cancer patients: a randomized, double-blind, placebo-controlled clinical trial

BACKGROUND

The postoperative inflammatory response contributes to tissue healing and recovery but overwhelming inflammation is associated with postoperative complications. n-3 (ω-3) PUFAs modulate inflammatory responses and may help to prevent a proinflammatory cascade.

OBJECTIVES

We aimed to investigate the effects of perioperative intravenous n-3 PUFAs on inflammatory cytokines in colon cancer surgery.

METHODS

This study is a randomized, double-blind, placebo-controlled clinical trial. Forty-four patients undergoing elective colon resection for nonmetastasized cancer were randomly assigned to 2 intravenous n-3 PUFA or saline control infusions the night before and the morning after surgery. Blood was sampled at 6 perioperative time points for changes in cytokines in serum and in LPS-stimulated whole blood samples and leukocyte membrane fatty acid profiles.

RESULTS

Twenty-three patients received saline and 21 patients received n-3 PUFAs. Patient and operation characteristics were equal between groups, except for open resection (saline n = 5 compared with n-3 PUFA n = 0, P = 0.056). Ex-vivo IL-6 after LPS stimulation was significantly higher in the n-3 PUFA group at the first day after surgery (P = 0.014), but not different at the second day after surgery (P = 0.467). White blood cell count was higher in the n-3 PUFA group at the fourth day after surgery (P = 0.029). There were more patients with infectious complications in the n-3 PUFA group (8 compared with 3, P = 0.036). There were no overall differences in serum IL-6, IL-10, C-reactive protein, and length of stay. The administration of n-3 PUFAs resulted in rapid increases in leukocyte membrane n-3 PUFA content.

CONCLUSIONS

In the n-3 PUFA group a clear relation with serum and LPS-stimulated cytokines was not found but, unexpectedly, more infectious complications occurred. Caution is thus required with the off-label use of a perioperative intravenous n-3 PUFA emulsion as a standalone infusion in the time sequence reported in the present study in colon resections with primary anastomosis. This trial was registered at clinicaltrials.gov as NCT02231203.

Endocrine-Metabolic Response in Patients Undergoing Multiple Body Contouring Surgeries After Massive Weight Loss

BACKGROUND

The endocrine-metabolic response to trauma is directly related to its magnitude, but little is known about the adverse effects of combined surgical procedures on morbidity.

OBJECTIVES

The authors sought to evaluate risk factors by measuring the endocrine-metabolic response in patients who underwent multiple body-contouring surgeries after massive weight loss.

METHODS

This prospective, randomized, interventional study included 46 massive weight loss patients who experienced a weight loss >30% of their body mass index (BMI) and were referred for body contouring surgery. Patients were randomly allocated to the control group (n = 10) or intervention group (n = 36), which in turn was divided into 3 subgroups (n = 12, each) according to BMI, surgical time, and scar length values. Blood samples were collected from all patients at different time points to assess biological stress markers.

RESULTS

Levels of IL-6 in patients in the higher ranges of BMI and operating time and with more extensive scar length were significantly higher in the immediate postoperative period compared with baseline. Concentrations of noradrenaline were significantly higher 24 hours after surgery compared with baseline only in patients in the higher range of operating time. A higher level of IL-6 at 72 hours after surgery compared with baseline was associated with more extensive scar length. Levels of other biological stress markers did not significantly differ.

CONCLUSIONS

The combination of surgical procedures did not significantly affect the concentrations of most biological stress markers. The variable of operating time most influenced increase in plasma concentrations of stress markers.

LEVEL OF EVIDENCE: 1

Prognostic Value of Serum Procalcitonin level for the Diagnosis of Bacterial Infections in Critically-ill Patients

Background

Procalcitonin (PCT) is a diagnostic biomarker for bacterial infections in critically-ill patients. However, the cut-off value of PCT for the diagnosis of bacterial infections is unclear and unreliable. This study aimed to determine the optimal cut-off value of PCT for the diagnosis of bacterial infections in critically-ill patients.

Materials and Methods

We conducted a retrospective study involving 311 adult patients who had been admitted to the medical or surgical intensive care unit for more than 24 hours from 2013 to 2015. At least one blood test for PCT level was performed for all patients within the first 24 hours of suspecting an infection.

Results

One hundred and fifty-seven patients had bacterial infections, while 154 did not. Patients with bacterial infections had a significantly higher median PCT level than those without bacterial infections (1.90 ng/mL vs. 0.16 ng/mL, P <0.001). The area under the receiver operating characteristic curve of PCT for discriminating between bacterial and non-bacterial infections was 0.874 (95% confidence interval: 0.834, 0.914; P <0.001). The optimal cut-off value of PCT for differentiating between fevers due to bacterial infections from those due to non-bacterial infections was 0.5 ng/mL, with a sensitivity of 84.7%, specificity of 79.9%, positive predictive value of 81.1%, and negative predictive value of 83.7%.

Conclusion

PCT was found to be an accurate biomarker for the diagnosis of bacterial infections among patients admitted to medical and surgical intensive care units. The optimal cut-off value of PCT for the diagnosis of bacterial infections was 0.5 ng/mL.

Serum alpha1 -proteinase inhibitor concentrations in dogs with systemic inflammatory response syndrome or sepsis

OBJECTIVE

To determine whether the concentration of serum canine alpha₁ -proteinase inhibitor (cα₁ -PI) has diagnostic or prognostic utility in dogs with sepsis or noninfectious systemic inflammatory response syndrome (SIRS).

DESIGN

Prospective, observational study from May to December 2010.

SETTING

University teaching hospital ICU.

ANIMALS

Sixty-nine client-owned dogs: 19 dogs with SIRS or sepsis and 50 healthy control dogs.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Serum and plasma samples were collected from dogs with SIRS or sepsis on the day of hospital admission and once on the following 2 days, and on a single day in healthy controls. Patients were assessed using the 10-parameter Acute Patient Physiologic and Laboratory Evaluation (APPLE_full ) and 5-parameter (APPLE_fast ) score. Serum cα₁ -PI concentrations were measured, compared among groups of dogs, and evaluated for a correlation with the concentration of serum C-reactive protein, plasma interleukin-6, tumor necrosis factor-α, the APPLE scores, and survival to discharge. Serum cα₁ -PI concentrations were significantly lower in dogs with SIRS/sepsis (P < 0.001) than in healthy controls. While day 1 serum cα₁ -PI concentrations did not differ between dogs with SIRS and those with sepsis (P = 0.592), septic dogs had significantly lower serum cα₁ -PI concentrations on days 2 (P = 0.017) and 3 (P = 0.036) than dogs with SIRS. Serum cα₁ -PI concentrations did not differ between survivors and nonsurvivors (P = 1.000), but were inversely correlated with the APPLE_full score (ρ = -0.48; P = 0.040) and plasma interleukin-6 concentrations (ρ = -0.50; P = 0.037).

CONCLUSIONS

These results suggest a role of cα₁ -PI as a negative acute phase protein in dogs. The concentration of serum cα₁ -PI at the time of hospital admission does not have utility to identify dogs with sepsis from those with noninfectious SIRS, but may be a useful surrogate marker for early stratification of illness severity.

Identification of potential biomarkers of sepsis using bioinformatics analysis

Sepsis is defined as the systemic inflammatory response to infection and is one of the leading causes of mortality in critically ill patients. The goal of the present study is to elucidate the molecular mechanism of sepsis. Transcription profile data (GSE12624) were downloaded that had a total of 70 samples (36 sepsis samples and 34 non-sepsis samples) from the Gene Expression Omnibus database. Protein-protein interaction network analysis was conducted in order to comprehensively understand the interactions of genes in all samples. Hierarchical clustering and analysis of covariance (ANCOVA) global test were performed to identify the differentially expressed clusters in the networks, followed by function and pathway enrichment analyses. Finally, a support vector machine (SVM) was performed to classify the clusters, and 10-fold cross-validation method was performed to evaluate the classification results. A total of 7,672 genes were obtained after preprocessing of the mRNA expression profile data. The PPI network of genes under sepsis and non-sepsis status collected 1,996/2,147 genes and 2,645/2,783 interactions. Moreover, following the ANCOVA global test (P<0.05), 24 differentially expressed clusters with 12 clusters in septic and 12 clusters in non-septic samples were identified. Finally, 207 biomarker genes, including CDC42, CSF3R, GCA, HMGB2, RHOG, SERPINB1, TYROBP SERPINA1, FCER1 G and S100P in the top six clusters, were collected using the SVM method. The SERPINA1, FCER1 G and S100P genes are thought to be potential biomarkers. Furthermore, Gene oncology terms, including the intracellular signaling cascade, regulation of programmed cell death, regulation of cell death, regulation of apoptosis and leukocyte activation may participate in sepsis.

Deep anesthesia worsens outcome of rats with inflammatory responses

OBJECTIVE

We tested the hypothesis that deep anesthesia with sevoflurane, known as a potent immunomodulator, for 4 h would worsen the 24-h outcomes of rats through modulation of the inflammatory responses.

METHODS

Forty-nine male Wistar rats, administered low dose of lipopolysaccharide (0.5 mg/kg) intravenously to elicit moderate inflammatory responses mimicked mild surgical stress, underwent one minimum alveolar concentration (MAC) or 2 MAC sevoflurane anesthesia for 4 h. The 24-h survival rate, arterial blood gases, plasma interleukin (IL)-6 and tumor necrosis factor (TNF)-α concentrations, and rate of T lymphocyte apoptosis in spleen were evaluated. We further examined the effects of hypotension and TNF-α discharge on the survival rate.

RESULTS

The survival rate in 2 MAC group was significantly lower accompanied with decreased base excess and increased level of cytokines (IL-6, TNF-α) compared to 1 MAC group. The apoptosis rate did not differ between the two groups. Neither norepinephrine infusion to restore hypotension nor administration of anti-TNF-α antibody improved the outcome in the 2 MAC group.

CONCLUSIONS

Deep anesthesia with sevoflurane even for a short-term period augments the release of inflammatory cytokines evoked by inflammatory insults like surgical stress, impairs the acid-base balance, and subsequently deteriorates the outcomes.

Alpha-1 Antitrypsin as a Therapeutic Agent for Conditions not Associated with Alpha-1 Antitrypsin Deficiency

Alpha-1 antitrypsin is a positive acute phase reactant whose serum level rises in response to inflammatory stress, presumably to balance pro-inflammatory processes. In addition to its serine protease inhibitory action, alpha-1 antitrypsin exhibits broader anti-inflammatory and immunomodulatory activity, and increasing its serum concentration by the administration of exogenous alpha-1 antitrypsin to above-normal levels potentially could be therapeutic in conditions other than alpha-1 antitrypsin deficiency. In vitro observations, studies in animal models and in some instances early human trials suggest that intravenous or inhaled alpha-1 antitrypsin has beneficial effects in type 1 diabetes, viral infections, graft-versus-host disease, cystic fibrosis, and alpha-1 antitrypsin-replete chronic obstructive pulmonary disease among others. While the results of pivotal clinical trials have not been reported to date, new indications for alpha-1 antitrypsin therapy are likely to emerge in the future based on currently available scientific data.

Inflammatory mediators in intra-abdominal sepsis or injury - a scoping review

Introduction

Inflammatory and protein mediators (cytokine, chemokine, acute phase proteins) play an important, but still not completely understood, role in the morbidity and mortality of intra-abdominal sepsis/injury. We therefore systematically reviewed preclinical and clinical studies of mediators in intra-abdominal sepsis/injury in order to evaluate their ability to: (1) function as diagnostic/prognostic biomarkers; (2) serve as therapeutic targets; and (3) illuminate the pathogenesis mechanisms of sepsis or injury-related organ dysfunction.

Methods

We searched MEDLINE, PubMed, EMBASE and the Cochrane Library. Two investigators independently reviewed all identified abstracts and selected articles for full-text review. We included original studies assessing mediators in intra-abdominal sepsis/injury.

Results

Among 2437 citations, we selected 182 studies in the scoping review, including 79 preclinical and 103 clinical studies. Serum procalcitonin and C-reactive protein appear to be useful to rule out infection or monitor therapy; however, the diagnostic and prognostic value of mediators for complications/outcomes of sepsis or injury remains to be established. Peritoneal mediator levels are substantially higher than systemic levels after intra-abdominal infection/trauma. Common limitations of current studies included small sample sizes and lack of uniformity in study design and outcome measures. To date, targeted therapies against mediators remain experimental.

Conclusions

Whereas preclinical data suggests mediators play a critical role in intra-abdominal sepsis or injury, there is no consensus on the clinical use of mediators in diagnosing or managing intra-abdominal sepsis or injury. Measurement of peritoneal mediators should be further investigated as a more sensitive determinant of intra-abdominal inflammatory response. High-quality clinical trials are needed to better understand the role of inflammatory mediators.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-015-1093-4) contains supplementary material, which is available to authorized users.

Nitric oxide as a regulator of B. anthracis pathogenicity

Nitric oxide (NO) is a key physiological regulator in eukaryotic and prokaryotic organisms. It can cause a variety of biological effects by reacting with its targets or/and indirectly inducing oxidative stress. NO can also be produced by bacteria including the pathogenic Bacillus anthracis; however, its role in the infectious process only begins to emerge. NO incapacitates macrophages by S-nitrosylating the intracellular proteins and protects B. anthracis from oxidative stress. It is also implicated in the formation of toxic peroxynitrite. In this study we further assessed the effects of B. anthracis NO produced by the NO synthase (bNOS) on bacterial metabolism and host cells in experiments with the bNOS knockout Sterne strain. The mutation abrogated accumulation of nitrite and nitrate as tracer products of NO in the culture medium and markedly attenuated growth in both aerobic and microaerobic conditions. The regulatory role of NO was also suggested by the abnormally high rate of nitrate denitrification by the mutant in the presence of oxygen. Anaerobic regulation mediated by NO was reflected in reduced fermentation of glucose by the mutant correlating with the reduced toxicity of bacteria toward host cells in culture. The toxic effect of NO required permeabilization of the target cells as well as the activity of fermentation-derived metabolite in the conditions of reduced pH. The host cells demonstrated increased phosphorylation of major survivor protein kinase AKT correlating with reduced toxicity of the mutant in comparison with Sterne. Our global proteomic analysis of lymph from the lymph nodes of infected mice harboring bacteria revealed numerous changes in the pattern and levels of proteins associated with the activity of bNOS influencing key cell physiological processes relevant to energy metabolism, growth, signal transduction, stress response, septic shock, and homeostasis. This is the first in vivo observation of the bacterial NO effect on the lymphatic system.

The effect of synthetic C-reactive protein on the in vitro immune response of human PBMCs stimulated with bacterial reagents

Synthetic C-reactive protein (CRP) rescues mice from lethal endotoxin shock or bacterial infection by suppressing tumor necrosis factor (TNF-α), but in turn, enhances Kupffer cell phagocytic activity. We herein assessed the influence of CRP in human peripheral blood mononuclear cells (PBMCs). When human PBMCs were stimulated in vitro with penicillin-treated Streptococcus pyogenes, bacterial DNA motifs and lipopolysaccharide with or without synthetic CRP, CRP suppressed the production of TNF-α and IL-12, but not that of IFN-γ. This was also the case for the in vitro Shwartzman reaction induced in PBMCs. CRP also decreased high-mobility group box 1 production from macrophages, which is crucial in the later phase of endotoxin/septic shock. However, CRP upregulated the perforin expression by CD56⁺ NK cells and increased their antitumor cytotoxicity. CRP may thus be a potent immunomodulatory factor in the human immune system, suggesting its therapeutic potential for use against human septic shock.

Preventively enteral application of immunoglobulin enriched colostrums milk can modulate postoperative inflammatory response

Several studies demonstrated acute inflammatory response following traumatic injury. Inflammatory response during surgical interventions was verified by a significant increase of endotoxin plasma levels and a decrease of the endotoxin neutralizing capacity (ENC). However, the incidence of elevated endotoxin levels was significantly higher (89%) than detected bacterial translocation (35%). Thus parts or products of Gram-negative bacteria seem to translocate more easily into the blood circulation than whole bacteria. Along with the bacterial translocation, the inflammatory response correlated directly with the severity of the surgical intervention. In comparison after major and minor surgery Interleukin-6 (IL-6) and C-reactive protein (CRP) was also significantly different. Similar effects in mediator release were shown during endovascular stent graft placement and open surgery in infrarenal aortic aneurysm. Open surgery demonstrated a significant stronger endotoxin translocation and a decrease of ENC. Strategies to prevent translocation seem to be sensible. Colostrum is the first milk produced by the mammary glands within the first days after birth. It contains a complex system of immune factors and has a long history of use in traditional medicine. Placebo-controlled studies verified that prophylactic oral application of immunoglobulin-enriched colostrum milk preparation diminishes perioperative endotoxemia, prevents reduction of ENC and reduces postoperative CRP-levels, suggesting a stabilization of the gut barrier. This effect may be caused by immunoglobulin transportation by the neonatal receptor FcRn of the mucosal epithelium.In conclusion, there is an association of perioperative endotoxemia and the subsequent increase in mediators of the acute phase reaction in surgical patients. A prophylactic oral application of colostrum milk is likely to stabilize the gut barrier i.e. reduces the influx of lipopolysaccharides arising from Gram-negative bacterial pathogens and inhibits enterogenic endotoxemia. This appears to be a major mechanism underlying the therapeutic effect in patients at risk for Gram-negative septic shock.

[Regional anesthesia in patients with pre-existing infections or immunosuppression]

Regional anesthesia is the most effective procedure for acute pain therapy. Whether neuraxial and peripheral blocks in patients with pre-existing infectious conditions, immune deficits or other risk factors increase the risk of additional infections is unclear. Analyzing the available literature currently seems to indicate that the incidence of severe infectious complications is generally low. Diabetes, steroid therapy or malignant diseases are apparently present in many cases in which infections associated with regional anesthesia and analgesia have been described. A strict contraindication in patients with pre-existing systemic or local infections seems unjustifiable. A clear and documented risk-benefit ratio in these patients is mandatory.

Revisiting the white blood cell count: immature granulocytes count as a diagnostic marker to discriminate between SIRS and sepsis--a prospective, observational study

Background

Sepsis is a serious disease condition and a major cause of intensive care unit (ICU) admission. Its diagnosis in critically ill patients is complicated. To diagnose an infection rapidly, and to accurately differentiate systemic inflammatory response syndrome (SIRS) from sepsis, is challenging yet early diagnosis is vital for early induction of an appropriate therapy. The aim of this study was to evaluate whether the immature granulocyte (IG) count is a useful early diagnostic marker of sepsis compared to other markers. Therefore, a total of 70 consecutive surgical intensive care patients were assessed. IGs were measured from whole blood samples using an automated analyzer. C-reactive protein (CRP), lipopolysaccharide binding protein (LBP) and interleukin-6 (IL-6) concentrations were also determined. The observation period was a maximum of 21 days and ended with the patients’ discharge from ICU or death. Receiver operating characteristic (ROC) analyses were conducted and area under the curve (AUC) was calculated to determine sensitivities and specificities for the parameters.

Results

We found that the IG count significantly discriminates between infected and non-infected patients (P < 0.0001) with a sensitivity of 89.2% and a specificity of 76.4%, particularly within the first 48 hours after SIRS onset. Regarding the discriminative power for infection, the IG count was more indicative than other clinical parameters such as CRP, LBP and IL-6, which had a sensitivity of less than 68%. Additionally, the highest diagnostic odds ratio (DOR) with 26.7 was calculated for the IG count within the first 48 hours. During the course of the disease ROC curve analyses showed a superior positive predictive value of the IG count compared to the other measured parameters during the first five days following the fulfillment of SIRS criteria. However, the number of IGs was not correlated with ICU mortality.

Conclusions

The total number of IG in peripheral blood from ICU patients is a good marker to discriminate infected and non-infected patients very early during SIRS. However, the IG count is not suitable as a prognostic marker for mortality. Routine and serial measurement of IGs may provide new possibilities for rapid screening of SIRS patients on ICU with suspected infections.

Acute phase proteins in healthy and sick cats

Serum acute phase protein concentrations are used as diagnostic, therapeutic and prognostic markers in human and, less frequently, in animal medicine. The aim of this study was to determine how the health status and signalment of the cat are associated with concentrations of acute phase proteins. Generally, medians of the positive acute phase proteins appeared to be higher in sick cats compared to healthy cats. In multivariable regression models, log-transformed serum amyloid A concentration was higher in older cats, in sick and in female cats, while log-transformed α1-acid glycoprotein and haptoglobin concentrations were higher in older cats and were associated with interactions of health status (sick/healthy) and gender (male/female). The data from healthy cats in this study contribute to the limited knowledge of normal reference ranges for this species. This study highlights the potential of acute phase proteins as diagnostic markers in sick cats, but also emphasises that the signalment of the cat needs to be taken into consideration.

Peritoneal resorption capacity for lipopolysaccharide and interleukin-6 in acute zymosan-induced chemical peritonitis

AIM

To evaluate peritoneal resorption capacity for lipopolysaccharide (LPS) and interleukin-6 (IL-6) in a model of chemical peritonitis.

METHODS

Zymosan peritonitis was induced in anesthetized rats. LPS was injected intraperitoneally to different groups at 4 h (n = 10), 8 h (n = 9), 12 h (n = 9), and 24 h (n = 9) after peritonitis and to a control group (n = 8). Similarly, IL-6 was injected intraperitoneally to different groups at 4 h (n = 9), 8 h (n = 10), 12 h (n = 10), and 24 h (n = 10) after peritonitis, and to a control group (n = 10). Plasma levels of LPS or IL-6 were measured immediately after intraperitoneal injections of LPS or IL-6, respectively, and at 5, 15, 30, 45, and 60 min later.

RESULTS

There was no change over time in plasma LPS levels in the groups receiving LPS intraperitoneally (p = 0.4). There was highly significant change over time in the IL-6 level in the studied time periods in the groups receiving IL-6 intraperitoneally (p < 0.0001). There was an increase in the plasma IL-6 level when sampled at 4 h after peritonitis.

CONCLUSION

There was a reduction of resorption capacity of inflamed peritoneum for inflammatory mediators in acute chemical peritonitis.

Acute allograft rejection in human liver transplant recipients is associated with signaling through toll-like receptor 4

BACKGROUND AND AIMS

Toll-like receptor (TLR) signaling is a crucial step in initiating adaptive immune responses. In addition to recognizing endotoxin, TLR4 also recognizes endogenous ligands ('damage-associated structures'), which are released into the circulation in the peri-transplantation period. TLR2 to a lesser extent also recognizes these endogenous ligands. Multiple studies involving solid organ transplants demonstrate a clear association between TLR4 and allograft rejection. In the present study we assessed whether an association exists between TLR4 and TLR2-dependent responses and acute liver allograft rejection.

METHODS

The sample included 26 liver transplant recipients. Blood was taken pre-transplant and at multiple points over the first 14 days post-transplant. Monocytes were stimulated with TLR4 and TLR2 ligands, lipopolysaccharide and Pam-3-Cys, respectively. Monocyte TLR expression was determined using flow cytometry; enzyme-linked immunosorbent assays measured tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) production.

RESULTS

Nine (34.6%) patients experienced rejection. No differences existed in age, sex, disease or immunosuppression between rejectors and non-rejectors. Baseline TLR4 expression was significantly higher in rejectors (1.36 vs 1.02, P=0.01). There was no difference in TLR2 expression. In rejectors, baseline TLR4- and TLR2-dependent production of TNF-α and IL-6 was also significantly increased. Post-transplant, the two groups differed with regard to TLR4-dependent TNF-α production, with rejectors demonstrating progressive downregulation over the first week.

CONCLUSIONS

Prior to liver transplantation, patients who subsequently experience rejection demonstrate robust TLR4-dependent immune responses, which are not seen in those who do not reject. This supports the theory that damage-associated structures signaling through TLR4 may be responsible for the early activation of alloimmune T-cells, favoring allograft rejection.

Management of mechanical ventilation during laparoscopic surgery

Laparoscopy is widely used in the surgical treatment of a number of diseases. Its advantages are generally believed to lie on its minimal invasiveness, better cosmetic outcome and shorter length of hospital stay based on surgical expertise and state-of-the-art equipment. Thousands of laparoscopic surgical procedures performed safely prove that mechanical ventilation during anaesthesia for laparoscopy is well tolerated by a vast majority of patients. However, the effects of pneumoperitoneum are particularly relevant to patients with underlying lung disease as well as to the increasing number of patients with higher-than-normal body mass index. Moreover, many surgical procedures are significantly longer in duration when performed with laparoscopic techniques. Taken together, these factors impose special care for the management of mechanical ventilation during laparoscopic surgery. The purpose of the review is to summarise the consequences of pneumoperitoneum on the standard monitoring of mechanical ventilation during anaesthesia and to discuss the rationale of using a protective ventilation strategy during laparoscopic surgery. The consequences of chest wall derangement occurring during pneumoperitoneum on airway pressure and central venous pressure, together with the role of end-tidal-CO2 monitoring are emphasised. Ventilatory and non-ventilatory strategies to protect the lung are discussed.

Effect of major abdominal surgery on the host immune response to infection

PURPOSE OF REVIEW

The present review summarizes key studies on the effects of major abdominal surgery on the host response to infection published during the last 18 months.

RECENT FINDINGS

Surgical trauma causes stereotyped systemic proinflammatory and compensatory anti-inflammatory reactions. It is leukocyte reprogramming rather than general immune suppression. The list of recent findings is long. Preoperative infectious challenge was found to increase survival. Obesity is associated with increased production of interleukin-17A in peritonitis. Abdominal surgery alters expression of toll-like receptors (TLRs). The acute phase reaction down-regulates the transcription factor carbohydrate response element binding protein. Myosin light chain kinase activation is a final pathway of acute tight junction regulation of gut barrier and zonula occludens 1 protein is an essential effector. The brain is involved in regulating the immune and gut system. Elimination of lipopolysaccharide is challenging. Th1/Th2 ratio is lowered in patients with postoperative complications. Cholinergic anti-inflammatory pathways can inhibit tissue damage. The new substance PXL01 prevents adhesions. Postoperative infection causes incisional hernias. Hypothermia reduced human leukocyte antigen DR surface expression and delayed tumor necrosis factor clearance. Systems biology identified interferon regulatory factor 3 as the negative regulator of TLR signaling. Protective immunity could contribute defeating surgical infections.

SUMMARY

Systemic inflammation is the usual response to trauma. All organs seem to be involved and linked up in cybernetic systems aiming at reconstitution of homeostasis. Although knowledge is still fragmentary, it is already difficult to integrate known facts and new technologies are required for information processing. Defining criteria to develop therapeutic strategies requires much more insight into molecular mechanisms and cybernetics of organ systems.

Prevalence of endotoxemia after surgery and its association with ICU length of stay

Introduction

The aim of this observational study was to investigate the prevalence of endotoxemia after surgery and its association with ICU length of stay.

Methods

102 patients admitted to a university ICU after surgery were recruited. Within four hours of admission, functional data were collected and APACHE II severity score calculated. Arterial blood samples were taken and endotoxemia was measured by chemiluminescence (Endotoxin Activity (EA)). Patients were stratified according to their endotoxin levels (low, intermediate and high) and according to their surgical procedures. Differences between endotoxin levels were assessed by ANOVA, accepting P < 0.05 as significant. Data are expressed as mean ± SD.

Results

EA levels were low in 68 (66%) patients, intermediate in 17 (17%) and high in 17 (17%). Age (61 ± 17 years) and APACHE II score 8.3 ± 3.7 (P = 0.542) were not significantly different in the three EA groups. Functional parameters on admission were similar between EA groups: white blood cells 11093 ± 4605 cells/mm³ (P = 0.385), heart rate 76 ± 16 bpm (P = 0.898), mean arterial pressure 88.8 ± 13.6 mmHg (P = 0.576), lactate 1.18 ± 0.77 mmol/L (P = 0.370), PaO₂/FiO₂ 383 ± 109 mmHg (P = 0.474). Patients with high levels of EA were characterized by longer length of stay in the ICU: 1.9 ± 3.0 days in the low EA group, 1.8 ± 1.4 days in intermediate and 5.2 ± 7.8 days in high group (P = 0.038).

Conclusions

17% of our patients were characterized by high levels of endotoxemia as assessed by EA assay, despite their low level of complexity on admission. High levels of endotoxin were associated with a longer ICU length of stay.

New Insight in Loss of Gut Barrier during Major Non-Abdominal Surgery

Background

Gut barrier loss has been implicated as a critical event in the occurrence of postoperative complications. We aimed to study the development of gut barrier loss in patients undergoing major non-abdominal surgery.

Methodology/Principal Findings

Twenty consecutive children undergoing spinal fusion surgery were included. This kind of surgery is characterized by long operation time, significant blood loss, prolonged systemic hypotension, without directly leading to compromise of the intestines by intestinal manipulation or use of extracorporeal circulation. Blood was collected preoperatively, every two hours during surgery and 2, 4, 15 and 24 hours postoperatively. Gut mucosal barrier was assessed by plasma markers for enterocyte damage (I-FABP, I-BABP) and urinary presence of tight junction protein claudin-3. Intestinal mucosal perfusion was measured by gastric tonometry (P_rCO₂, P_r-aCO₂-gap). Plasma concentration of I-FABP, I-BABP and urinary expression of claudin-3 increased rapidly and significantly after the onset of surgery in most children. Postoperatively, all markers decreased promptly towards baseline values together with normalisation of MAP. Plasma levels of I-FABP, I-BABP were significantly negatively correlated with MAP at ½ hour before blood sampling (−0.726 (p<0.001), −0.483 (P<0.001), respectively). Furthermore, circulating I-FABP correlated with gastric mucosal P_rCO₂, P_r-aCO₂-gap measured at the same time points (0.553 (p = 0.040), 0.585 (p = 0.028), respectively).

Conclusions/Significance

This study shows the development of gut barrier loss in children undergoing major non-abdominal surgery, which is related to preceding hypotension and mesenterial hypoperfusion. These data shed new light on the potential role of peroperative circulatory perturbation and intestinal barrier loss.

Effect of major abdominal surgery on endotoxin release and expression of Toll-like receptors 2/4

BACKGROUND

Surgery can cause endotoxemia, and endotoxin aggregates to Toll-like receptors and acts proinflammatory; repetitive endotoxin application can cause tolerance. The objective of the study is to characterize early inflammatory response and expression of TLR2/4 during major abdominal surgery.

MATERIALS AND METHODS

A prospective controlled study of 20 patients with elective major abdominal surgery was performed. Blood samples were collected before and at a defined time after surgery. Endotoxemia, capability of plasma to inactivate endotoxin, cytokine release of LPS-stimulated mononuclear cells, quantitative TLR mRNA expression, and plasma concentrations of TNFalpha, IL-6, C-reactive protein (CRP), alpha(1)-acid glycoprotein, transferrin, and albumin were measured.

RESULTS

Surgery caused endotoxemia (p = 0.053), and the capability of plasma to inactivate endotoxin was reduced (p = 0.0002). Two hours postoperatively, the plasma concentrations of TNFalpha and IL-6 peaked significantly, but the liberation capacity of mononuclear cells for cytokines (TNFalpha, IL-1beta, IL-6) was significantly reduced. The concentration of CRP and alpha(1)-acid glycoprotein peaked 48 h postoperatively, but those of transferrin and albumin were significantly decreased (p < 0.001, respectively). Median mRNA expression of TLR2 and TLR4 of mononuclear cells was not altered, and there was no obvious trend over time.

CONCLUSION

Major abdominal surgery is associated with endotoxemia, reduced capability of plasma to inactivate endotoxin, cytokine kinetics resembling those of healthy man after experimentally given LPS, and substantial acute-phase reaction. The cytokine liberation of mononuclear cells suggests a state of postoperative endotoxin tolerance. Despite these substantial changes, trends in TLR2/4 expression are not obvious.

HIV infection and the gastrointestinal immune system

There has recently been a resurgence of interest in the gastrointestinal pathology observed in patients infected with HIV. The gastrointestinal tract is a major site of HIV replication, which results in massive depletion of lamina propria CD4 T cells during acute infection. Highly active antiretroviral therapy leads to incomplete suppression of viral replication and substantially delayed and only partial restoration of gastrointestinal CD4 T cells. The gastrointestinal pathology associated with HIV infection comprises significant enteropathy with increased levels of inflammation and decreased levels of mucosal repair and regeneration. Assessment of gut mucosal immune system has provided novel directions for therapeutic interventions that modify the consequences of acute HIV infection.

Preoperative Immunonutrition Suppresses Perioperative Inflammatory Response in Patients with Major Abdominal Surgery—A Randomized Controlled Pilot Study

BACKGROUND/AIM

Perioperative administration of immunoenriched diets attenuates the perioperative inflammatory response and reduces postoperative infection complications. However, many questions still remain unresolved in this area, such as the length of diet administration, diet composition, and the mechanisms involved. We performed an open, randomized, triple-arm study comparing the effect of two perioperative feeding regimens with a postoperative one.

METHODS

46 candidates for major elective surgery for malignancy in the upper gastrointestinal tract were randomized to drink preoperatively either 1 L of an immunoenriched formula (Impact) for 5 days (IEF group) or 1 L of Impact plus (Impact enriched with glycine) for 2 days (IEF plus group). The same product as the patient received preoperatively was given to both groups for 7 days postoperatively. In the control group (CON group), patients only received Impact for 7 days postoperatively; there was no preoperative treatment. The main outcome measures were postoperative C-reactive protein (CRP) serum levels.

RESULTS

In the two preoperatively supplemented groups (treatment groups), perioperative endotoxin levels, CRP (postoperative day 7), and TNF-alpha (postoperative days 1 and 3) levels were significantly lower compared to the CON group (p < .01). Furthermore, the length of postoperative IMU/ICU stay (Impact 1.9 +/- 1.3 days; Impact plus 2.2 +/- 1.1 days; control group 5.9 +/- 0.8 days) and length of hospital stay (Impact 19.7 +/- 2.3 days; Impact plus 20.1 +/- 1.3 days; control group 29.1 +/- 3.6 days) were both reduced in the treatment groups compared to the control group. Infectious complications (Impact 2/14 (14%); Impact plus 5/17 (29%); control group 10/15 (67%)) also showed a trend toward reduction in the treatment groups.

CONCLUSIONS

Perioperative administration of an immunoenriched diet significantly reduces systemic perioperative inflammation and postoperative complications in patients undergoing major abdominal cancer surgery, when compared with postoperative diet administration alone. A shortened preoperative feeding regimen of 2 days with Impact enriched with glycine (Impact plus) was as effective as Impact administered for 5 days preoperatively.

Changes in CRP, SAA and haptoglobin produced in response to ovariohysterectomy in healthy bitches and those with pyometra

The aim of the study was to assess changes in serum C-reactive protein (CRP), serum amyloid A component (SAA) and haptoglobin (Hp) concentrations in healthy bitches and in those with pyometra undergoing ovariohysterectomy, and to establish the usefulness of such determinations for monitoring the postoperative period. Our results indicate that CRP and SAA determinations serve to evaluate the severity of the inflammatory process in pyometra since the concentrations of these acute phase proteins were increased immediately after surgery and diminished thereafter. The CRP and SAA response was rapidly produced while Hp concentrations increased in a more gradual manner. Thus, postoperative concentrations of CRP and SAA provide valuable information on the subsidence of the inflammatory response during the uneventful postoperative period. Our findings also suggest that acute phase proteins might be useful diagnostic markers of early postoperative complications.

Clinical influence of vagotomy on postoperative acute phase response

BACKGROUND

Although there is increasing evidence suggesting that the vagus nerve functions as a connector between the nervous and immune systems in animals, little is known about the role of the vagus nerve in postoperative acute phase response in humans.

MATERIALS AND METHODS

The extent of fever and acute phase protein response and the production of inflammatory cytokine during the early postoperative period were compared among the patients who had undergone total gastrectomy including truncal vagotomy (n = 13), those having distal gastrectomy with division of vagal branches (n = 14), and the patients with vagal nerve preserving gastrectomy (n = 12).

RESULTS

There was no significant difference in serum levels of C-reactive protein, alpha-1-antirypsin, and interleukin-6 among the three groups. Also, postoperative maximum body temperature was similar.

CONCLUSIONS

Vagotomy did not influence acute phase response after gastric cancer surgery. A multipathway mechanism for acute phase response including the induction of fever is suggested.

Angiotensin II induces interleukin-6 in humans through a mineralocorticoid receptor-dependent mechanism

This study tested the hypothesis that angiotensin promotes oxidative stress and inflammation in humans via aldosterone and the mineralocorticoid receptor. We measured the effect of intravenous aldosterone (0.7 mug/kg per hour for 10 hours followed by 0.9 mug/kg per hour for 4 hours) and vehicle in a randomized, double-blind crossover study in 11 sodium-restricted normotensive subjects. Aldosterone increased interleukin (IL)-6 (from 4.7+/-4.9 to 9.4+/-7.1 pg/mL; F=4.94; P=0.04) but did not affect blood pressure, serum potassium, or high-sensitivity C-reactive protein. We next conducted a randomized, double-blind, placebo-controlled, crossover study to measure the effect of 3-hour infusion of angiotensin II (2 ng/kg per minute) and norepinephrine (30 ng/kg per minute) on separate days after 2 weeks of placebo or spironolactone (50 mg per day) in 14 salt-replete normotensive subjects. Angiotensin II increased blood pressure (increase in systolic pressure: 13.7+/-7.5 and 15.2+/-9.4 mm Hg during placebo and spironolactone, respectively; P<0.001 for angiotensin II) and decreased renal plasma flow (-202+/-73 and -167+/-112 mL/min/1.73 kg/m(2); P<0.001 for angiotensin II effect) similarly during placebo and spironolactone. Spironolactone enhanced the aldosterone response to angiotensin II (increase of 17.0+/-10.6 versus 9.0+/-5.7 ng/dL; P=0.002). Angiotensin II transiently increased free plasma F(2)-isoprostanes similarly during placebo and spironolactone. Angiotensin II increased serum IL-6 concentrations during placebo (from 1.8+/-1.1 to 2.4+/-1.4 pg/mL; F=4.5; P=0.04) but spironolactone prevented this effect (F=6.4; P=0.03 for spironolactone effect). Norepinephrine increased blood pressure and F(2)-isoprostanes but not aldosterone or IL-6. Aldosterone increases IL-6 in humans. These data suggest that angiotensin II induces IL-6 through a mineralocorticoid receptor-dependent mechanism in humans. In contrast, angiotensin II-induced oxidative stress, as measured by F(2)-isoprostanes, is mineralocorticoid receptor independent and may be pressor dependent.

Intestinal Permeability and Cytokine Inflammatory Response in Multiply Injured Patients

In experimental settings, the increased intestinal permeability (IP) following severe trauma is associated with increased serum concentrations of cytokines. Multiply injured patients are susceptible to the development of multiple organ failure (MOF). The aim of this study was to determine if altered IP after trauma was associated with upregulation of cytokines and if cytokines and IP influenced the development of MOF. In 30 multiply injured patients, IP was measured on days 2 and 4 after injury using the lactulose-mannitol (L-M) test, and the levels of tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), and IL-8 were determined simultaneously. The L-M ratio increased significantly from 0.049 (0.017-0.133) on day 2 to 0.150 (0.059-0.339) on day 4 (p < 0.02) On day 4, a significant correlation was also found between the L-M ratio and IL-6 (r = 0.43, p < 0.03). The IL-6 level on days 2 and 4 was significantly (p < 0.01 and p < 0.03, respectively) higher in MOF patients than in those without MOF, as was the TNF-alpha level on day 4 significantly higher (p < 0.04) in MOF patients. IP increases following multiple trauma, and on day 4 it correlates with the IL-6 level. However, in patients who develop MOF only cytokines are invariably increased, with IL-6 alone being significantly increased on both measurements in these patients.

[Role of plasma procalcitonin determination in the postoperative follow-up of cephalic pancreatoduodenectomy]

BACKGROUND

Procalcitonin (PCT) is widely accepted as an early marker of the severity of sepsis and its prognosis. This study was designed to evaluate the utility of PCT in the early diagnosis of immediate postoperative complications (infectious and non-infectious) following cephalic pancreatoduodenectomy (PD).

PATIENTS AND METHOD

Thirty-one patients who underwent elective PD were prospectively analyzed. The patients were divided into two groups according to the presence or absence of postoperative complications. Plasma PCT concentrations were determined by an immunochromatographic method. The correlation between PCT concentrations and the presence of complications, as well as the existence of statistically significant differences in PCT concentrations between the 2 groups of patients, were analyzed. The value of plasma PCT concentrations in predicting complications compared with that of other biochemical variables (C-reactive protein, lactic acid, base excess) and clinical parameters (systemic inflammatory response syndrome) was analyzed.

RESULTS

Significant differences in PCT concentrations were found between the two groups. An inverse correlation between marker levels and patient outcome was observed. The variables that best predicted the development of complications were PCT concentrations and axillary temperature.

CONCLUSIONS

Plasma PCT should be taken into account as a useful marker for postoperative clinical course in the follow-up of PD and for the early detection of non-infectious complications.

Increased levels of Candida albicans mannan-specific T-cell-derived antigen binding molecules in patients with invasive candidiasis

In addition to cytokines, CD4+ T cells have been found to secrete soluble, T-cell-derived antigen binding molecules (TABMs). These antigen-specific immunoproteins are thought to have immunoregulatory properties in the suppression of cell-mediated immunity (CMI) because they often associate with interleukin-10 (IL-10) and transforming growth factor beta. Decreased CMI causes susceptibility to infections caused by organisms which are normally nonpathogenic. In this situation, e.g., Candida albicans saprophytism may develop into invasive candidiasis. The difficult diagnosis of invasive candidiasis is based on the findings obtained from blood cultures and with tissue biopsy specimens, with some additional diagnostic value gained by the detection of Candida albicans mannan antigenemia and antimannan antibodies. In the present study, Candida albicans mannan-specific TABM (CAM-TABM) levels in the sera of patients with invasive candidiasis (n = 11), Candida colonization (n = 11) and noncolonization (n = 10), recurrent vulvovaginal candidiasis (n = 30), and atopic eczema dermatitis syndrome (n = 59) and healthy controls (n = 30) were analyzed. For 14 participants, the effect of mannan stimulation on TABM production and gamma interferon (IFN-gamma) and IL-4 mRNA expression by peripheral blood lymphocytes was also studied. It was demonstrated that CAM-TABM production was the highest in patients with invasive candidiasis and that CAM-TABM levels could distinguish Candida-colonized patients from noncolonized patients. In addition, the CAM-TABM level was directly related to mRNA expression for IL-4 but not IFN-gamma. These results reinforce the view that TABMs are associated with decreased CMI, immunoregulation, and the T-helper cell 2-type immune response.

Portal and systemic endotoxemia in abdominal operations: the significance of acute abdomen

Little evidence is available for the implication of bacterial translocation in cases of acute abdomen. Intraoperative endotoxemia in both portal and systemic circulation was studied in 20 surgical patients with acute abdomen and in 36 controls undergoing elective abdominal surgery. Blood was sampled simultaneously from a mesenteric vein immediately after opening the peritoneum and from a peripheral vein. Endotoxin was measured by a colorimetric Limulus amebocyte lysate assay and malondialdehyde (MDA) was measured by the thiobarbiturate assay and passage through a high-performance liquid chromatography (HPLC) system as a marker of the oxidative status. LPS concentrations (mean +/- SE) in portal vein blood from patients with acute abdomen was 5.69 +/- 1.58 and from patients with chronic diseases 1.05 +/- 0.07 EU/ml (P < 0.0001). Respective values for the systemic circulation were 4.98 +/- 1.47 and 1.36 +/- 0.31 EU/ml (P < 0.0001). Concentrations of MDA (mean +/- SE) in portal vein blood from patients with acute abdomen was 11.16 +/- 4.00 and from patients with chronic diseases was 10.56 +/- 2.39 mum (P NS). Positive correlations were observed between endotoxin and MDA in both portal and systemic circulation. These results indicate increased levels of endotoxin in acute abdominal conditions pointing to the gut as the site of origin of the bacterial products.

Use of serum amyloid A and other acute phase reactants to monitor the inflammatory response after castration in horses: a field study

REASONS FOR PERFORMING THE STUDY

Early recognition of excessive inflammation and infectious complications after surgery, leading to early institution of therapy, reduces post operative discomfort and facilitates recovery. Because serum amyloid A (SAA) is a highly sensitive marker of inflammation, measurements of SAA and other acute phase reactants in the equine surgical patient may be valuable in assisting clinical assessment of post operative inflammation.

OBJECTIVES

To investigate changes in inflammatory markers after castration and to correlate levels of acute phase reactants with clinical severity of inflammation after castration.

METHODS

Leucocyte numbers and blood levels of iron, SAA and fibrinogen were determined before castration and on Days 3 and 8 post operatively in 2 groups of horses; Group 1 (n = 11) had mild post operative inflammation and an uncomplicated recovery and Group 2 (n = 7) had local clinical signs of moderate to severe inflammation.

RESULTS

Both groups had elevated serum SAA levels at Day 3 post operatively. In Group 1 concentrations had returned to preoperative levels by Day 8, whereas in Group 2 concentrations remained elevated. Plasma fibrinogen concentrations in serum increased to equal levels in both groups and stayed elevated throughout the study period. Serum iron concentrations of Group 1 did not change in response to castration, whereas concentrations in Group 2 decreased below preoperative levels on Day 8. Leucocyte numbers remained unchanged during the post operative period in both groups.

CONCLUSIONS

Serum SAA and iron profiles reflected the course of inflammation and their levels correlated with the clinical severity of inflammation. In contrast, fever and changes in leucocyte numbers, which are usually considered to be hallmarks of inflammation and infection, were not useful for monitoring post operative recovery.

POTENTIAL RELEVANCE

Measurements of SAA and iron may improve post operative monitoring. As sustained inflammation may indicate that the surgical wound has become infected, SAA and iron measurements may facilitate early recognition and hence early treatment of infection.

Alpha1-antitrypsin deficiency in 26-year-old subjects: lung, liver, and protease/protease inhibitor studies

BACKGROUND

Clinical and biochemical signs of lung and liver disease have been followed prospectively in a birth cohort of individuals with alpha1-antitrypsin (AAT) deficiency.

OBJECTIVE

At age 26 years, the focus was on clinical health, lung and liver function tests, and plasma markers of the protease/antiprotease balance. The effect of early childhood environment and symptoms was also studied.

METHODS

Eligible individuals were 26-year-old subjects with AAT deficiency (PiZ, n = 122; PiZ -, n = 2; PiSZ/S-, n = 53) and control subjects (PiMM, n = 44). Of the original AAT-deficient subjects, 119 completed the clinical examination and 134 answered the questionnaire.

RESULTS

The prevalence of respiratory symptoms did not differ between the PiZ and SZ groups. Sixteen percent of PiZ and 14% of PiSZ subjects had asthma. Four current smokers (67%) and 22% of ex-smokers/never-smokers reported recurrent wheezing (p = 0.03). No difference in FEV1 or FEV1/FVC ratio was found between the PiZ, SZ (5% being smokers), and MM individuals (all nonsmokers). A decreased FEV1/FVC ratio was found in PiZ subjects with neonatal cholestasis, compared to remaining PiZ subjects (p = 0.02). Recurrent wheezers at age 2 years with AAT deficiency had decreased FEV1/FVC ratio (p = 0.025) at age 26 years. None had clinical symptoms of liver disease. Six percent of PiZ and 9% of PiSZ subjects had a marginal increase of serum alanine aminotransferase; 7% of PiZ and 4% of PiSZ had abnormal gamma-glutamyl transferase test results. The PiZ and SZ individuals had decreased plasma albumin (p = 0.0002). Secretory leukocyte protease inhibitor (SLPI) was increased in PiZ and SZ subjects compared to PiMM subjects (p = 0.0001). Neutrophil lipocalin was decreased in PiZ subjects (p = 0.0004) and PiSZ subjects (p = 0.001) compared to PiMM individuals. The elastase/AAT complex concentration was lower in AAT-deficient subjects (p = 0.0001).

CONCLUSION

Twenty-six-year-old PiZ and SZ individuals (5% smokers) had normal lung function test results, and 4 to 9% had marginal deviations in liver test results. Analyses of SLPI and neutrophil lipocalin, a marker of neutrophil activity, indicate compensatory changes in the AAT-deficiency state.

Effects of perioperative parenteral glutamine-dipeptide supplementation on plasma endotoxin level, plasma endotoxin inactivation capacity and clinical outcome

BACKGROUND & AIMS

We evaluated perioperative plasma endotoxin, plasma soluble CD14 molecule (sCD14), plasma endotoxin inactivation capacity (EIC) changes and clinical outcome after glutamine was provided in parenteral feedings to patients on whom gastrointestinal operations were performed using a prospective, randomized, double-blind study design.

METHODS

Forty patients undergoing gastrointestinal operations were randomized into two groups, each had 20 patients. One group received standard parenteral nutrition and the other received the same formulation but supplemented with the dipeptide alanyl-glutamine, the two groups were isonitrogenous. The infusion was started from 1 day before operation to the 3rd day after operation for 5 days. Blood samples were collected on the morning of 1 day before operation, 3h after operation, and on the morning of 1, 4 and 7 days after operation and analyzed for plasma endotoxin level, plasma sCD14 level and EIC.

RESULTS

There were no differences between the two groups on plasma endotoxin level. After surgery a rapid reduction in plasma EIC was observed in both groups, a significant restoration of the plasma EIC was observed on the morning of 1 and 4 days after surgery in the study group (0.12+/-0.02 and 0.078+/-0.022 EU/mL, respectively, P < 0.01). A significant rise in plasma sCD14 level was found in the study group on the morning of 1 and 4 days after surgery (14.32+/-1.69 and 10.34+/-1.14 microg/mL, respectively, P < 0.01). Shortened hospital stay was observed in the study group (11.7+/-2.0 days in the control group and 10.6+/-1.2 days on the study group respectively, P = 0.03).

CONCLUSION

Perioperative parenteral nutrition supplemented with dipeptide alanyl-glutamine ameliorated postoperative immunodepression without direct effect on endotoxemia.

The Effect of Granulocyte Macrophage-Colony Stimulating Factor on Bacterial Translocation after Administration of 5-Fluorouracil in Rats

BACKGROUND

After surgical resection for colorectal carcinoma there is a high recurrence rate and, therefore, adjuvant chemotherapy may be useful in some patients. 5-Fluorouracil (5-FU) is the most commonly used chemotherapeutic agent in the management of patients with colorectal cancer. However, gastrointestinal injury induced by chemotherapeutic agents may result in bacterial translocation from the gut into the systemic circulation. Granulocyte macrophage-colony stimulating factor (GM-CSF) may be used to prevent this side effect by means of macrophage activity stimulation.

MATERIALS AND METHODS

A total of 45 rats were divided into three groups. Control group received intraperitoneal saline solution, 5-FU and GM-CSF groups received 50 mg/kg/day 5-FU intravenous infusion and GM-CSF group also received 200 ng/day GM-CSF subcutaneously for 6 days. Intestinal tissue was also sampled for pathological examination at day 7. Plasma levels of tumor necrosis factor-alpha and interleukin-6 were determined, bacterial translocation was quantified by lymph node, liver and spleen culture, and plasma endotoxin content was measured.

RESULTS

White blood cell counts of the 5-FU rats were significantly lower than in the control and GM-CSF groups (P < 0.01). The plasma endotoxin, tumor necrosis factor-alpha and interleukin-6 levels in the 5-FU and GM-CSF groups were significantly increased at day 7 compared with the control groups (P < 0.01), but these levels were significantly lower in the GM-CSF group compared to the 5-FU group (P < 0.01). 5-FU intervention caused significant increase in the frequencies of bacterial translocation at liver, spleen, mesenteric lymph node, and portal blood. Compared with 5-FU group, GM-CSF decreased the bacterial translocation (P < 0.01).

CONCLUSIONS

This study observed that the administration of 5-FU resulted in bacterial translocation. Activation of inflammatory response with GM-CSF is highly effective in prevention of bacterial translocation in 5-FU interventions.

Effects of postoperative enteral immune-enhancing nutrients on plasma endotoxin level, plasma endotoxin inactivation capacity and clinical prognosis

AIM: To investigate the effects of immune-enhancing nutrients such as glutamine, arginine and w-3-fatty acid on the plasma endotoxin, plasma sCD14, plasma endotoxin inactivation capacity and clinical prognosis of patients received gastrointestinal operations.

METHODS: Forty patients received gastrointestinal operations were randomly divided into two groups (20 for each). One group received standard enteral nutrition and the other was fed the standard formulation supplemented with glutamine, arginine and ω-3-fatty acid. One day after the operation, the patients were administered with the above nutrients that contained equal energy and equal amount of nitrogen for 7 d. Blood samples were collected 1 day before the operation and 1, 4 and 7 d after the operation for the detection of plasma endotoxin level and endotoxin inactivation capacity (EIC). The infection-associated complications and the prognosis were also evaluated.

RESULTS: There were no significant differences between the two groups in plasma endotoxin levels and the infection-associated complications. After the operation, a rapid reduction in plasma endotoxin inactivation capacity was observed in both groups, but a significant restoration the plasma endotoxin inactivation capacity was observed 4 d after the operation in the study group (0.12±0.02 kEU/L and 0.078±0.022 kEU/L for the control and study group, respectively, P<0.01). Shortened hospital stay was observed in the study group (11.7±2.0 and 10.6±1.2 d in the control study group, respectively, P<0.05).

CONCLUSION: Perioperative parenteral nutrition supplemented with immune-enhancing nutrients can ameliorate the postoperative immunodepression, but it has no significant effect on endotoxemia.

Effects of postoperative enteral immune-enhancing diet on plasma endotoxin level, plasma endotoxin inactivation capacity and clinical outcome

This study examined the postoperative plasma endotoxin level, plasma endotoxin inactivation capacity and clinical outcome after administration of an enteral diet supplemented with glutamine, arginine and omega-3-fatty acid in patients undergoing gastrointestinal operations on an prospective, randomized and double-blind design. 40 patients undergoing gastrointestinal operations were randomized into two groups, with each having 20 patients. One group received standard enteral nutrition and the other was fed the formulation supplemented with glutamine, arginine and omega-3-fatty acid. The two groups were isonitrogenous. The infusion was started from day 1 after surgery and continued for 7 days. Blood samples were collected on the morning of day 1 before operation and on the morning of 1, 4 and 7 day(s) after operation and analyzed for plasma endotoxin level and endotoxin inactivation capacity (EIC). Our study found no differences between the two groups on plasma endotoxin level. After surgery a rapid reduction in plasma endotoxin inactivation capacity was observed in both groups, a significant recovery of the plasma endotoxin inactivation capacity was observed on morning of day 4 after surgery in the study group (0.12 +/- 0.02 EU/mL and 0.078 +/- 0.022 EU/mL respectively, P < 0.01). Shortened hospital stay was observed in the experimental group (11.7 +/- 2.0 days in the control group and 10.6 +/- 1.2 days in the experimental group respectively, P = 0.03). It is concluded that perioperative parenteral nutrition supplemented with glutamine, arginine and omega-3-fatty acid ameliorated postoperative immunodepression but without direct effect on endotoxemia.

Diagnostic and predictive value of the silkworm larvae plasma test for postoperative infection following gastrointestinal surgery

OBJECTIVE

To determine whether the silkworm larvae plasma (SLP) test is a reliable diagnostic marker of infection in patients with infectious complications following gastrointestinal surgery.

DESIGN

Prospective study.

SETTING

Department of Surgery, University Hospital, Shiga University of Medical Science.

PATIENTS

One hundred and twelve adult patients undergoing gastrointestinal surgery

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Thirty-nine of 112 patients developed infectious complications (infected group). Seven patients with sepsis (severely infected group) and 32 patients without sepsis (minor infected group) were observed. The operation time, blood loss, and age were significantly greater in both infected groups than in the noninfected group. The systemic inflammatory response syndrome score on postoperative day (POD) 1 and POD7 was highest in the severely infected group. The increase in C-reactive protein on POD3 and POD7 was significantly higher in both infected groups than in the noninfected group. White blood cell counts on POD7 were elevated significantly higher in the severely infected group than in the other groups. Immediately after surgery, SLP activity significantly increased compared with presurgery in all groups and was significantly higher in the minor and severely infected groups than in the noninfected group. The increased SLP activity returned to preoperative levels in the minor and noninfected groups; however, SLP activity in the severely infected groups remained high throughout the observational period. The most significant factor and time point that predicted infectious complications were the SLP test on POD1; sensitivity 66.7%, specificity 90.4%, positive and negative predictive values 78.8% and 83.5%. The area under the receiver operating characteristic curve for the SLP test was 0.813 +/- 0.046.

CONCLUSIONS

The SLP test appears to be a useful marker of diagnosis and prediction of infectious complications following gastrointestinal surgery. Moreover, the SLP test may be able to evaluate not only the existence but also the severity of infection in surgical patients.

Clinical laboratory differentiation of infectious versus non-infectious systemic inflammatory response syndrome

OBJECTIVE

To evaluate the accuracy of C-reactive protein (CRP), procalcitonin (PCT), neopterin, and endotoxin in the differential diagnosis of sepsis and non-infectious systemic inflammatory response syndrome (SIRS).

METHODS

A Medline database and references from identified articles were used to perform a literature search relating to the differential diagnosis of sepsis versus non-infectious SIRS.

RESULTS

CRP, PCT, and neopterin are released both in sepsis and in non-infectious inflammatory disease. CRP and PCT are equally effective, although not perfect, in differentiating between sepsis and non-infectious SIRS. However, CRP and PCT have different kinetics and profiles. The kinetics of CRP is slower than that of PCT, and CRP levels may not further increase during more severe stages of sepsis. On the contrary, PCT rises in proportion to the severity of sepsis and reaches its highest levels in septic shock. PCT tends to be higher in nonsurvivor than in survivor. Therefore, PCT demonstrated a closer correlation with the severity of sepsis and outcome than CRP. Unlike CRP and PCT, neopterin is increased in viral infection as well as bacterial infection, and neopterin is also a useful indicator of sepsis. Endotoxemia was detected in no more than half of patients with Gram-negative bacteremia, and Gram-negative bacteremia was detected in half of patients with endotoxemia.

CONCLUSIONS

The diagnostic capacity of PCT is superior to that of CRP due to the close correlation between PCT levels and the severity of sepsis and outcome. Neopterin is very useful in the diagnosis of viral infection. The endotoxin assay in combination with CRP, PCT, or neopterin may help as a diagnostic marker for Gram-negative bacterial infection.

Effects of volumetric vs. pressure-guided fluid therapy on postoperative inflammatory response: a prospective, randomized clinical trial

OBJECTIVE

To compare intrathoracic blood volume (ITBV) guided fluid management and central venous pressure (CVP) guided therapy in ameliorating the progression of early systemic inflammatory response in patients undergoing major surgery.

DESIGN

Prospective, randomized clinical trial.

PATIENTS

Forty patients undergoing major abdominal surgery were randomized into CVP and ITBV groups.

INTERVENTIONS

In the CVP group the target CVP was 8-12 mmHg while in the ITBV group the goal was to keep the ITBV between 850 and 950 ml/m2 during the operation.

MEASUREMENTS AND RESULTS

Hemodynamic parameters were determined by single arterial thermodilution. Measurements were repeated every 30 min intraoperatively. Serum procalcitonin (PCT) and C-reactive protein (CRP) was monitored preoperatively, on ICU admission, and then daily for 3 days. Serum TNF-alpha levels were measured intraoperatively hourly and then daily for 3 days. There was no significant difference between the two groups regarding hemodynamic parameters at any assessment point. In the overall population changes in the stroke volume index showed a significant correlation with changes in CVP and ITBV. TNF-alpha levels remained in the normal range intraoperatively and during the three postoperative days in both groups. Preoperatively normal PCT and CRP levels increased significantly postoperatively, without significant differences between the groups.

CONCLUSIONS

ITBV guided fluid therapy did not alter the magnitude of inflammatory response as monitored by serum PCT, CRP, and TNF-alpha in the early postoperative period.

Influence of diabetes on the exacerbation of an inflammatory response in cardiovascular tissue

Coronary artery disease results from an inflammatory process in blood vessels of afflicted individuals. This process is accelerated with diabetes for reasons that are largely unknown. Recent evidence indicates that infection at sites remote from the heart leads to bacteremia and endotoxemia, thereby stimulating systemic inflammation, which represents an important risk factor for atherosclerosis. We examined the inflammatory response of the heart/aorta of diabetic db/db mice that develop type II diabetes. Subcutaneous inoculation of lipopolysaccharide was used to mimic a local infection. This stimulated an up-regulation of adhesion molecules, cytokines, and chemokines via an endotoxemia that was significantly more rapid and more pronounced in the diabetic compared with normal mice. The 13- to 30-fold induction of key proinflammatory molecules in the heart/aorta of diabetic mice even exceeded that at the site of inoculation. Given that infection, bacteremia, and endotoxemia are relatively frequent events in humans, these results identify a putative mechanism for increased cardiovascular heart disease in diabetes.

Inflammatory response after abdominal surgery

Surgical manipulation of the gut elicits an inflammatory cascade within the intestinal muscularis that contributes to postoperative bowel dysmotility. A range of cytokines is sequentially released into the peritoneal fluid following abdominal surgery, their concentrations reflecting the magnitude of surgical trauma. The overproduction of inflammatory mediators might have detrimental effects on organ function and contribute to the enhanced risk of anastomotic leakage in the presence of sepsis. Specific cellular immune functions such as the microbicidal activity of peritoneal phagocytes are depressed after elective surgery, imposing a risk of infectious complications. Laparoscopic surgery decreases the local and systemic production of cytokines and acute-phase reactants, and better preserves peritoneal immunity compared with open surgery. As concluded from animal studies, the gas used for the pneumoperitoneum may possess substantial immunomodulatory activity.

Microbial translocation and inflammatory response in patients with acute peritonitis

BACKGROUND

In peritonitis, increased production of cytokines and changes in the splanchnic cellular immune system may cause translocation of bacteria and endotoxins. The aims of this study were to assess the frequency of translocation and relate translocation to the immune response in patients with acute peritonitis.

METHODS

Patients with local (LP, n=20) or general peritonitis (GP, n=15) were compared with controls (C, n=12). Blood was obtained preoperatively for cultures, and analyses of endotoxin and cytokines (tumour necrosis factor-alpha, interleukins 6 and 10). Mesenteric lymph nodes (MLNs) were excised for culturing and immunohistochemistry using antibodies CD4, CD8 and CD68.

RESULTS

Positive blood and MLN cultures were not obtained in controls. DNA typing proved bacterial translocation in one patient with local and one patient with general peritonitis. Thus translocation was proven to occur in 6% of patients with peritonitis. Endotoxaemia was predominantly found in the GP group. Cytokines increased during peritonitis and more so in patients with GP than in those with LP. More CD8 and CD68 cells were found in MLNs from LP patients than in C patients and more CD4 and CD8 cells in LP patients than in GP patients. There was no significant difference in this regard between the GP and C groups.

CONCLUSIONS

Bacterial translocation occurs during acute peritonitis but seems to be fairly infrequent. Peritonitis causes significant inflammatory cellular reactions.