Interleukin 1 receptor antagonist and E-selectin concentrations: a comparison in patients with severe acute pancreatitis and severe sepsis

E and P Selectins as Potential Markers in the Assessment of the Severity of Acute Pancreatitis

OBJECTIVES

Acute pancreatitis (AP) is commonly associated with the release of adhesion molecules such as E and P selectins. We designed the present study to evaluate the role of selectins as potential markers that could reflect the severity of the disease.

METHODS

One hundred fifty patients with AP constituted the patient group, whereas 70 healthy volunteers established the control group. In both groups, blood samples were taken for measurements of E selectin, P selectin, caspase-cleaved cytokeratin 18, and total soluble cytokeratin 18 levels on admission and days 1, 2, 4, and 6.

RESULTS

Values of E and P selectins on admission were both elevated compared with control subjects (P < 0.01). The nonsurvivors had higher values of E selectin (P < 0.04) and P selectin (P < 0.03) on admission. Levels of E and P selectin showed positive correlation with the length of stay (P < 0.05). E selectin on admission yielded a sensitivity of 75% and 78% specificity, whereas P selectin had a sensitivity of 67% and 91% specificity.

CONCLUSIONS

Selectin values in the early course of AP may play a role as indicators of overall prognosis, which may help physicians in better understanding the pathophysiology of a benign disease that may have serious and detrimental complications.

The Interplay between Inflammation, Coagulation and Endothelial Injury in the Early Phase of Acute Pancreatitis: Clinical Implications

Acute pancreatitis (AP) is an inflammatory disease with varied severity, ranging from mild local inflammation to severe systemic involvement resulting in substantial mortality. Early pathologic events in AP, both local and systemic, are associated with vascular derangements, including endothelial activation and injury, dysregulation of vasomotor tone, increased vascular permeability, increased leukocyte migration to tissues, and activation of coagulation. The purpose of the review was to summarize current evidence regarding the interplay between inflammation, coagulation and endothelial dysfunction in the early phase of AP. Practical aspects were emphasized: (1) we summarized available data on diagnostic usefulness of the markers of endothelial dysfunction and activated coagulation in early prediction of severe AP; (2) we reviewed in detail the results of experimental studies and clinical trials targeting coagulation-inflammation interactions in severe AP. Among laboratory tests, d-dimer and angiopoietin-2 measurements seem the most useful in early prediction of severe AP. Although most clinical trials evaluating anticoagulants in treatment of severe AP did not show benefits, they also did not show significantly increased bleeding risk. Promising results of human trials were published for low molecular weight heparin treatment. Several anticoagulants that proved beneficial in animal experiments are thus worth testing in patients.

Serum Soluble Fms-Like Tyrosine Kinase 1 (sFlt-1) Predicts the Severity of Acute Pancreatitis

Organ failure is the most important determinant of the severity of acute pancreatitis (AP). Soluble fms-like tyrosine kinase 1 (sFlt-1) is positively associated with organ failure in sepsis. Our aim was to evaluate the diagnostic utility of automated sFlt-1 measurements for early prediction of AP severity. Adult patients (66) with AP were recruited, including 46 with mild (MAP), 15 with moderately-severe (MSAP) and 5 with severe AP (SAP). Serum and urine samples were collected twice. Serum sFlt-1 was measured with automated electrochemiluminescence immunoassay. Serum concentrations of sFlt-1 were significantly higher in patients with MSAP and SAP as compared to MAP. SAP patients had the highest concentrations. At 24 and 48 h, sFlt-1 positively correlated with inflammatory markers (leukocyte count, C-reactive protein), kidney function (creatinine, urea, cystatin C, serum and urine neutrophil gelatinase-associated lipocalin, urine albumin/creatinine ratio), D-dimer and angiopoietin-2. sFlt-1 positively correlated with the bedside index of severity in AP (BISAP) score and the duration of hospital stay. Serum sFlt-1 above 139 pg/mL predicted more severe AP (MSAP + SAP). In the early phase of AP, sFlt-1 is positively associated with the severity of AP and predicts organ failure, in particular kidney failure. Serum sFlt-1 may be a practical way to improve early assessment of AP severity.

Laboratory markers predicting severity of acute pancreatitis

Acute pancreatitis (AP) is an inflammatory disease of highly variable severity, ranging from mild cases with low mortality to severe cases with high mortality. Numerous biomarkers have been studied as potential early predictors of the severity of this disease so that treatment can be optimally tailored to prevent complications. We aim to present and discuss the most relevant biomarkers for early severity assessment in AP that have been studied to date. We review the current literature on biomarkers that have been used to predict the severity in AP. C-reactive protein (CRP) is still considered to be the gold standard, with a cut-off value of 150 mg/ml 48 h after disease onset. Other markers, including procalcitonin (PCT) and interleukin 6 (IL-6) have been implemented in some hospitals, but are not used on a routine basis. Most other markers, including acute phase proteins (LBP, SAA, PTX3), cytokines (Il-8, TNF-a, MIF), activation peptides of pancreatic proteases (TAP, CAPAP, PLAP), antiproteases (AAT, a2M), adhesion molecules (ICAM-1, selectins, E-cadherin) and leukocyte-derived enzymes (PA2, PMN-E) have shown some promising results but have not been routinely implemented. Furthermore, new and interesting biomarkers (Copeptin, TRX-1, Ang-2, E-2) have shown good results, but more research is needed to determine if they could play a role in the future. Various reasons why new markers for disease severity have not been adopted in daily routine include low accuracy, cumbersome laboratory techniques and high cost. Despite these difficulties, research is still very active in finding new markers to predict the severity of AP.

Soluble adhesion molecules as markers for sepsis and the potential pathophysiological discrepancy in neonates, children and adults

Sepsis is a severe and life-threatening systemic inflammatory response to infection that affects all populations and age groups. The pathophysiology of sepsis is associated with aberrant interaction between leukocytes and the vascular endothelium. As inflammation progresses, the adhesion molecules that mediate these interactions become shed from cell surfaces and accumulate in the blood as soluble isoforms that are being explored as potential prognostic disease biomarkers. We critically review the studies that have tested the predictive value of soluble adhesion molecules in sepsis pathophysiology with emphasis on age, as well as the underlying mechanisms and potential roles for inflammatory shedding. Five soluble adhesion molecules are associated with sepsis, specifically, E-selectin, L-selectin and P-selectin, intercellular adhesion molecule-1 and vascular cell adhesion molecule-1. While increased levels of these soluble adhesion molecules generally correlate well with the presence of sepsis, their degree of elevation is still poorly predictive of sepsis severity scores, outcome and mortality. Separate analyses of neonates, children and adults demonstrate significant age-dependent discrepancies in both basal and septic levels of circulating soluble adhesion molecules. Additionally, a range of both clinical and experimental studies suggests protective roles for adhesion molecule shedding that raise important questions about whether these should positively or negatively correlate with mortality. In conclusion, while predictive properties of soluble adhesion molecules have been researched intensively, their levels are still poorly predictive of sepsis outcome and mortality. We propose two novel directions for improving clinical utility of soluble adhesion molecules: the combined simultaneous analysis of levels of adhesion molecules and their sheddases; and taking age-related discrepancies into account. Further attention to these issues may provide better understanding of sepsis pathophysiology and increase the usefulness of soluble adhesion molecules as diagnostic and predictive biomarkers.

Circulating sICAM-1 and sE-Selectin as biomarker of infection and prognosis in patients with systemic inflammatory response syndrome

BACKGROUND

Vascular endothelium activation is a key pathogenic step in systemic inflammatory response syndrome (SIRS) that can be triggered by both microbial and sterile proinflammatory stimuli. The relevance of soluble adhesion molecules as clinical biomarkers to discriminate between infectious and non-infectious SIRS, and the individual patient prognosis, has not been established.

METHODS

We prospectively measured by sandwich ELISA, serum levels of soluble E-Selectin (sE-Selectin), soluble vascular cell adhesion molecule-1 (sVCAM-1), soluble intercellular adhesion molecule-1 (sICAM-1) and soluble intercellular adhesion molecule-2 (sICAM-2) at ICU admission and at days 3, 7, 14 and 28 in patients with sepsis and at days 3 and 7 in patients with non-infectious SIRS.

RESULTS

At ICU admission, sE-Selectin, sVCAM-1 and sICAM-1 in patients with infectious SIRS were significantly higher than those found in patients with non-infectious SIRS. ROC analysis revealed that the AUC for infection identification was best for sICAM-1 (0.900±0.041; 95% CI 0.819-0.981; p<0.0001). Moreover, multivariate analysis showed that 4 variables were significantly and independently associated with mortality at 28 days: male gender (OR 15.90; 95% CI, 2.54-99.32), MODS score (OR 5.60; 95% CI, 1.67-18.74), circulating sE-Selectin levels (OR 4.81; 95% CI, 1.34-17.19) and sVCAM-1 concentrations (OR 4.80; 95% CI, 1.34-17.14).

CONCLUSIONS

Patients with SIRS secondary to infectious or non-infectious etiology show distinctive patterns of disturbance in serum soluble adhesion molecules. Serum ICAM-1 is a reliable biomarker for classifying patients with infectious SIRS from those with non-infectious SIRS. In addition, soluble E-Selectin is a prognostic biomarker with higher levels in patients with SIRS and fatal outcome.

Activated Protein C Does Not Alleviate the Course of Systemic Inflammation in the APCAP Trial

The study aimed to determine the effect of the activated protein C on the course of systemic inflammation in the APCAP (activated protein C in acute pancreatitis) trial where we randomized 32 patients with severe acute pancreatitis to receive either recombinant activated protein C (drotrecogin alfa activated) (n = 16) or placebo (n = 16) for 96 hours. In the present study, we present the time course of the patients' plasma or serum levels of soluble markers (IL-8, IL-6, IL-10, IL-1ra, sE-selectin, PCT) and monocyte and neutrophil cell surface (CD11b, CD14, CD62L, HLA-DR) markers of systemic inflammatory response during the first 14 days after the randomization. The results of the intervention and placebo groups were comparable showing that recombinant APC treatment did not alter the course of systemic inflammation in severe acute pancreatitis. Our finding is in accordance with the clinical findings in the APCAP trial indicating that the intervention did not affect evolution of multiple organ dysfunctions.

Chaiqin Chengqi Decoction decreases IL-6 levels in patients with acute pancreatitis

OBJECTIVE

In this paper, we investigated the effect of the traditional Chinese medicine Chaiqin Chengqi Decoction (CQCQD) on serum cytokines in acute pancreatitis (AP) patients.

METHODS

Peripheral blood samples from 107 AP patients were collected within the first 48 h of AP onset and on the 10th day of CQCQD treatment. Control samples were collected from 20 healthy individuals. Serum proinflammatory cytokines tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), and anti-inflammatory cytokines IL-10 and IL-1β receptor antagonist (IL-1ra) were examined using the Luminex 100 system.

RESULTS

Within the first 48 h of AP onset, IL-6 and IL-1ra levels in severe AP (SAP) patients were significantly higher than those in mild AP (MAP) patients, but IL-10 levels in SAP patients were significantly lower than those in MAP patients. Proinflammatory cytokine IL-6 was significantly decreased after CQCQD treatment (P<0.05), especially in SAP patients (n=25 of 36, P<0.05). The hospitalization time of SAP patients was shortened significantly when serum IL-6 decreased after CQCQD treatment (P<0.05).

CONCLUSIONS

CQCQD decreased proinflammatory cytokine IL-6 levels in AP patients.

Clinical utility of biomarkers of endothelial activation in sepsis--a systematic review

INTRODUCTION

A strong biologic rationale exists for targeting markers of endothelial cell (EC) activation as clinically informative biomarkers to improve diagnosis, prognostic evaluation or risk-stratification of patients with sepsis.

METHODS

The objective was to review the literature on the use of markers of EC activation as prognostic biomarkers in sepsis. MEDLINE was searched for publications using the keyword 'sepsis' and any of the identified endothelial-derived biomarkers in any searchable field. All clinical studies evaluating markers reflecting activation of ECs were included. Studies evaluating other exogenous mediators of EC dysfunction and studies of patients with malaria and febrile neutropenia were excluded.

RESULTS

Sixty-one studies were identified that fulfilled the inclusion criteria. Overall, published studies report positive correlations between multiple EC-derived molecules and the diagnosis of sepsis, supporting the critical role of EC activation in sepsis. Multiple studies also reported positive associations for mortality and severity of illness, although these results were less consistent than for the presence of sepsis. Very few studies, however, reported thresholds or receiver operating characteristics that would establish these molecules as clinically-relevant biomarkers in sepsis.

CONCLUSIONS

Multiple endothelial-derived molecules are positively correlated with the presence of sepsis in humans, and variably correlated to other clinically-important outcomes. The clinical utility of these biomarkers is limited by a lack of assay standardization, unknown receiver operating characteristics and lack of validation. Additional large-scale prospective clinical trials will be required to determine the clinical utility of biomarkers of endothelial activation in the management of patients with sepsis.

Sepsis biomarkers: a review

INTRODUCTION

Biomarkers can be useful for identifying or ruling out sepsis, identifying patients who may benefit from specific therapies or assessing the response to therapy.

METHODS

We used an electronic search of the PubMed database using the key words "sepsis" and "biomarker" to identify clinical and experimental studies which evaluated a biomarker in sepsis.

RESULTS

The search retrieved 3370 references covering 178 different biomarkers.

CONCLUSIONS

Many biomarkers have been evaluated for use in sepsis. Most of the biomarkers had been tested clinically, primarily as prognostic markers in sepsis; relatively few have been used for diagnosis. None has sufficient specificity or sensitivity to be routinely employed in clinical practice. PCT and CRP have been most widely used, but even these have limited ability to distinguish sepsis from other inflammatory conditions or to predict outcome.

Severe acute pancreatitis: Pathogenetic aspects and prognostic factors

Approximately 20% of patients with acute pancreatitis develop a severe disease associated with complications and high risk of mortality. The purpose of this study is to review pathogenesis and prognostic factors of severe acute pancreatitis (SAP). An extensive medline search was undertaken with focusing on pathogenesis, complications and prognostic evaluation of SAP. Cytokines and other inflammatory markers play a major role in the pathogenesis and course of SAP and can be used as prognostic markers in its early phase. Other markers such as simple prognostic scores have been found to be as effective as multifactorial scoring systems (MFSS) at 48 h with the advantage of simplicity, efficacy, low cost, accuracy and early prediction of SAP. Recently, several laboratory markers including hematocrit, blood urea nitrogen (BUN), creatinine, matrix metalloproteinase-9 (MMP-9) and serum amyloid A (SAA) have been used as early predictors of severity within the first 24 h. The last few years have witnessed a tremendous progress in understanding the pathogenesis and predicting the outcome of SAP. In this review we classified the prognostic markers into predictors of severity, pancreatic necrosis (PN), infected PN (IPN) and mortality.

Activation des molécules d’adhésion chez les patients en choc septique

OBJECTIVE

To analyze the pattern of adhesion molecules in patients with septic shock. Data sources. - References obtained from Pubmed databank.

DATA EXTRACTION

Models of inflammation linking endothelial dysfunction, adhesion molecules and septic states were analyzed.

DATA SYNTHESIS

The endothelium has been identified as the central effector in the inflammatory response. Adhesion molecules are strongly involved in the inflammatory process by modulating the leukocyte trafficking. The most important adhesion molecules are the selectins (E-, L-, and P-selectins) and members of the immunoglobulin superfamily (intercellular adhesion molecule-1 and vascular cell adhesion molecule-1). Plasma levels of these molecules are increased in septic shock patients, which may be related to a marked activation of the endothelium. However, a dichotomous profile is observed between plasma and tissue expression. The inhibition of adhesive molecule actions could make it possible to control the inflammatory response.

Serum profiles of E-selectin, interleukin-10, and interleukin-6 and oxidative stress parameters in patients with acute pancreatitis and nonpancreatic acute abdominal pain

INTRODUCTION

Excessive inflammatory response is one of the major causes of early mortality in acute pancreatitis (AP).

AIM

To evaluate the serum profiles of E-selectin, interleukin (IL)-6, and IL-10 along with their correlation to the markers of oxidative stress and neutrophil activation in patients with AP and patients with nonpancreatic acute abdominal pain (NPAAP).

METHODOLOGY

This prospective clinical study included 56 patients with AP (28 with mild AP and 28 with severe AP) as well as 15 patients with NPAAP.

RESULTS

Serum concentrations of E-selectin, IL-10, and IL-6 and plasma concentrations of polymorphonuclear leukocyte elastase (determined on days 1-3, 5, and 10 after admission) were the highest in severe AP during the first 3 days and then declined. At day 10, the E-selectin level in severe AP was still higher than that in mild AP, and the IL-10 concentration increased again. There was no elevation in the E-selectin concentration in NPAAP patients, and IL-10 levels remained unchanged in mild AP. Oxidative stress, measured by serum malondialdehyde and 4-hydroxyalkenals levels, was the most pronounced in severe AP.

CONCLUSIONS

The serum E-selectin concentration is markedly elevated in severe AP and is less in mild AP but not in NPAAP. It may result from stimulation with different inflammatory mediators or indicate vascular endothelium injury mediated by oxidative stress, especially in the severe form of AP.

New laboratory tests in acute pancreatitis

Acute pancreatitis (AP) is a common disease with wide variation of severity. The diagnosis of AP is usually based on high serum amylase or lipase values but the accuracy of these methods is considered unsatisfactory. One in five of the patients develops a severe disease and carries a considerable risk of development of organ failure and high mortality. Early detection of patients with severe AP and especially those with increased risk of organ failure is importance since such patients seem to benefit from treatment in an intensive care unit started as soon as possible after presentation. In addition to enzymological methods, increasing interest has been focused on laboratory markers reflecting the level of inflammatory response in AP. At present, in routine clinical work the most commonly used severity marker is serum C-reactive protein, the concentration of which rises too slowly to be used for early prediction of severity. New therapies aiming at modifying the course of systemic inflammation in AP are being developed and therefore monitoring the patient's immune inflammatory status is needed. In this review article we present the current knowledge of laboratory tests, which has been evaluated for diagnostic and prognostic purposes in AP.

Humoral markers of severity and prognosis of critical illness

Despite the considerable advances made in understanding the pathophysiology of systemic inflammation during critical illness, clinical progress has been elusive as it remains a very deadly condition. Cortisol and thyroid hormone levels can be as predictive of outcome as the commonly used severity parameters (i.e. APACHE). Indeed, levels of endocrine humoral substances such as arachidonic acids, nitric oxide, endothelin, calcitonin precursors, leptin and adenosine correlate with the severity and outcome of critical illness. Furthermore, calcitonin precursors represent a potentially new hormokine paradigm, being transcriptionally activated in all cells in response to infection. The cytokines are immune markers that often correlate with severity and outcome, but their release is transient. In contrast, the so-called acute phase proteins, such as C-reactive protein and serum amyloid A, are highly sensitive to inflammatory activity and can be important markers of severity and outcome. Leukocyte esterase, adhesion molecules, platelet activating factor and activated protein C are additional humoral immune markers; the replacement of the latter has been shown to be a promising therapeutic option. Natriuretic peptides are neurocrine humoral markers that have important cardiovascular implications. The level of macrophage migrating inhibitory factor, released by the pituitary, is elevated in sepsis and counteracts glucocorticoid action. Cellular markers to severe stress include the enhanced expression of protective substances in the form of heat shock proteins. High mobility group-1 is a DNA-binding protein and a late mediator of the inflammatory response. Apoptotic markers such as the soluble fas ligand are also elevated in inflammation. In summary, during critical illness, the endocrine, immune and nervous systems elaborate a multitude of humoral markers, the roles of which merit further scrutiny in order to improve therapeutic outcome.

Endothelial-derived selectins in the development of organ dysfunction in acute pancreatitis

OBJECTIVE

The development of organ dysfunction is the principal determinant of outcome in acute pancreatitis and is mediated through a systemic inflammatory response characterized by leukocyte and endothelial cell activation. Up-regulation of the endothelial cell adhesion molecules, E-selectin and P-selectin, is important for endothelial/leukocyte interactions. Levels of serum-soluble E-selectin and P-selectin have been suggested as markers of endothelial activation. This study examines the kinetics of serum-soluble selectins in patients with acute pancreatitis complicated by organ dysfunction.

DESIGN

Prospective observational study.

SETTING

University teaching hospital with a specialist hepato-pancreatico-biliary service.

PATIENTS

Eighteen patients with acute pancreatitis were studied, nine of whom had organ dysfunction.

MEASUREMENTS AND MAIN RESULTS

Serial venous blood samples were collected on the first 3 days after admission for measurement of soluble E-selectin and P-selectin by enzyme-linked immunosorbent assay. In all patients, soluble P-selectin concentrations decreased significantly during the study period. Nonsurvivors had significantly higher levels of soluble P-selectin than survivors. In contrast, soluble E-selectin increased significantly during the study period in patients with organ dysfunction, whereas it remained constant in patients without evidence of organ dysfunction.

CONCLUSIONS

These results suggest a role for endothelial-derived selectins in the development of organ dysfunction in patients with acute pancreatitis. The observed temporal differences in serum selectin concentrations is in keeping with in vitro observations of endothelial selectin expression.

Modulation of soluble phases of endothelial/leukocyte adhesion molecule 1, intercellular adhesion molecule 1, and vascular cell adhesion molecule 1 with interleukin-1beta after experimental endotoxic challenge

OBJECTIVE

To evaluate the effect of treatment with interleukin 1beta (IL-1beta) on the concentrations of soluble adhesion molecules after an endotoxic challenge.

DESIGN

Randomized, controlled study.

SETTING

Experimental Unit, Virgen de las Nieves University Hospital.

SUBJECTS

Seventy-two female CBA/H mice of 20 to 21 g, supplied by the animal center of the Experimental Unit.

INTERVENTION

The mice were randomized into three groups of 24. Group 1 (sham) received two intraperitoneal (ip) doses of 0.1 mL of phosphate-buffered saline; group 2 (lipopolysaccharide) was injected with 125 mg/kg lipopolysaccharide (Escherichia coli) (i.p.) 24 hrs after 0.1 mL of phosphate-buffered saline; group 3 was pretreated with 80 ng (i.p.) of IL-1beta per mouse 24 hrs before the endotoxic challenge.

MEASUREMENTS AND MAIN RESULTS

At 1, 2, 4, and 24 hrs after the endotoxic challenge, the concentrations of soluble endothelial/leukocyte adhesion molecule 1 (ELAM-1), intercellular adhesion molecule 1 (ICAM-1), and vascular cell adhesion molecule 1 (VCAM-1) were measured in the three groups. There was a significant increase (p <.01) in these concentrations at these times in comparison with the sham group. The use of IL-1beta produced a significant decrease (p <.05) in the three molecules among the treated group versus the group submitted only to the challenge; concentrations of ELAM-1 significantly decreased to below those of the sham group, and those of VCAM-1 reduced to levels that did not significantly differ from those of the sham group.

CONCLUSION

Endotoxin administration significantly increases the concentrations of soluble ELAM-1, ICAM-1, and VCAM-1 in mice. Treatment with IL-1beta significantly decreases these concentrations, probably attenuating cell injury and organ dysfunction.

Scoring systems for assessing organ dysfunction and survival

Sepsis is an ongoing disease process carrying a high risk of organ failure and death. Scoring systems to determine disease severity and risk of mortality may be useful in patient management and clinical trial enrollment, although the role of either type of score in the determination of admission or discharge criteria or in decisions relating to the continuation or withholding of treatment remains controversial. General scoring systems have been developed to quantify the severity of illness and the risk of mortality in ICU patients. Ideally, these should be customized before use in patients with septic shock, but in general noncustomized models are used, and this potential limitation should be acknowledged. Prognostic scores are remarkably reliable at predicting outcome in groups of patients and give an indication of severity of disease on admission, but they are unable to provide detail on how a patient is responding to treatment or on the disease progression. Organ function scores, however, can be assessed repeatedly and used to define a patient's progress. This approach can thus be used to evaluate individual patient care, to identify patients for enrollment in clinical trials or epidemiologic analyses, and to assess morbidity measures in clinical trials of new interventions. Organ dysfunction scores are just that, descriptors of organ dysfunction, and although high values correlate well with mortality, prognostication is not their prime aim; organ dysfunction scores and outcome prediction scores should rather be viewed as complementary systems in the description of ICU populations.