Serum macrophage migration inhibitory factor is an early marker of pancreatic necrosis in acute pancreatitis

Circulating soluble CD163 is associated with reduced Glasgow Coma Scale Score and 1-year all-cause mortality in traumatized patients

Soluble CD163 (sCD163) is a biomarker of macrophage activation, not previously investigated in the circulation of traumatized patients. A biobank of 398 adult trauma patients was analyzed. Patients with an Injury Severity Score (ISS) >8 served as trauma patients (n = 195) and those with ISS ≤ 8 as trauma controls (n = 203). Serum samples obtained upon admission, 15h and 72h after were analyzed for sCD163 using an in-house ELISA. Multiple linear regression was used to analyze the association between admission levels of sCD163 with, 1: overall trauma severity (ISS), and 2: severity of injury to specified organs using Abbreviated Injury Score (AIS) and Glasgow Coma Scale (GCS). The association between the peak level of sCD163 with 1-year all-cause mortality was analyzed by logistic regression analysis. Median admission levels of sCD163 were higher in trauma patients than trauma controls [2.32 (IQR 1.73 to 2.86) vs. 1.92 (IQR 1.41 to 2.51) mg/L, p < 0.01]. Worsening GCS score was associated with a 10.3% (95% CI: 17.0 to 3.1, p < 0.01) increase in sCD163. Increasing Head-AIS score was associated with a 5.1% (95% CI: -0.5 to 11.0, p = 0.07) increase in sCD163. The remaining AIS scores and ISS were not consistently associated with sCD163 admission levels. Each mg/L increase in sCD163 peak level had an odds ratio 1.34 (95%CI: 0.98 to 1.83), p = 0.06) after adjustment for age, sex, and GCS. Circulating sCD163 is increased in traumatized patients and associated with worsening GCS. Our findings suggest an association between circulating sCD163 levels with 1-year all-cause mortality.

Fire in the belly: A scoping review of the immunopathological mechanisms of acute pancreatitis

Introduction

Acute pancreatitis (AP) is characterised by an inflammatory response that in its most severe form can cause a systemic dysregulated immune response and progression to acute multi-organ dysfunction. The pathobiology of the disease is unclear and as a result no targeted, disease-modifying therapies exist. We performed a scoping review of data pertaining to the human immunology of AP to summarise the current field and to identify future research opportunities.

Methods

A scoping review of all clinical studies of AP immunology was performed across multiple databases. Studies were included if they were human studies of AP with an immunological outcome or intervention.

Results

205 studies met the inclusion criteria for the review. Severe AP is characterised by significant immune dysregulation compared to the milder form of the disease. Broadly, this immune dysfunction was categorised into: innate immune responses (including profound release of damage-associated molecular patterns and heightened activity of pattern recognition receptors), cytokine profile dysregulation (particularly IL-1, 6, 10 and TNF-α), lymphocyte abnormalities, paradoxical immunosuppression (including HLA-DR suppression and increased co-inhibitory molecule expression), and failure of the intestinal barrier function. Studies including interventions were also included. Several limitations in the existing literature have been identified; consolidation and consistency across studies is required if progress is to be made in our understanding of this disease.

Conclusions

AP, particularly the more severe spectrum of the disease, is characterised by a multifaceted immune response that drives tissue injury and contributes to the associated morbidity and mortality. Significant work is required to develop our understanding of the immunopathology of this disease if disease-modifying therapies are to be established.

D-dopachrome tautomerase in cardiovascular and inflammatory diseases-A new kid on the block or just another MIF?

Macrophage migration inhibitory factor (MIF) as well as its more recently described structural homolog D-dopachrome tautomerase (D-DT), now also termed MIF-2, are atypical cytokines and chemokines with key roles in host immunity. They also have an important pathogenic role in acute and chronic inflammatory conditions, cardiovascular diseases, lung diseases, adipose tissue inflammation, and cancer. Although our mechanistic understanding of MIF-2 is relatively limited compared to the extensive body of evidence available for MIF, emerging data suggests that MIF-2 is not only a functional phenocopy of MIF, but may have differential or even oppositional activities, depending on the disease and context. In this review, we summarize and discuss the similarities and differences between MIF and MIF-2, with a focus on their structures, receptors, signaling pathways, and their roles in diseases. While mainly covering the roles of the MIF homologs in cardiovascular, inflammatory, autoimmune, and metabolic diseases, we also discuss their involvement in cancer, sepsis, and chronic obstructive lung disease (COPD). A particular emphasis is laid upon potential mechanistic explanations for synergistic or cooperative activities of the MIF homologs in cancer, myocardial diseases, and COPD as opposed to emerging disparate or antagonistic activities in adipose tissue inflammation, metabolic diseases, and atherosclerosis. Lastly, we discuss potential future opportunities of jointly targeting MIF and MIF-2 in certain diseases, whereas precision targeting of only one homolog might be preferable in other conditions. Together, this article provides an update of the mechanisms and future therapeutic avenues of human MIF proteins with a focus on their emerging, surprisingly disparate activities, suggesting that MIF-2 displays a variety of activities that are distinct from those of MIF.

Macrophage migration inhibitory factor (MIF) of golden pompano (Trachinotus ovatus) is involved in the antibacterial immune response

Macrophage migration inhibitory factor (MIF) is a pleiotropic cytokine with a unique structure involved in immune regulation and inflammation. In the present study, we identified a MIF from Trachinotus ovatus (golden pompano) and analyzed its function. TroMIF shares high homology (58.26%-94.78%) with the other known MIF sequences of vertebrates. TroMIF is most closely related to large yellow croaker (Larimichthys crocea). The expression of TroMIF was most abundant in the liver and head kidney, and was significantly up-regulated after Edwardsiella tarda infection. The subcellular localization of TroMIF was mostly distributed in the cytoplasm. In vitro results revealed that the recombinant protein rTroMIF could inhibit the migration of head kidney lymphocytes (HKLs) and macrophages (HKMs) and enhance the phagocytic activity of HKMs. As a pro-inflammatory cytokine, rTroMIF could increase the expression levels of some pro-inflammatory cytokines, including tumor necrosis factor-alpha (TNF-α), interleukin 1-beta (IL-1β), IL-6, IL-8, and interferon-gamma (IFN-γ) and decrease the expression of IL-10. The rTroMIF was proved to have enzymatic redox activity in vitro. Furthermore, overexpression of TroMIF in the head kidney cell line of golden pompano could significantly enhance its ability to resist E. tarda infection from 1 h to 4 h. The knockdown of TroMIF expression induced a significant increase in the number of bacteria after E. tarda infection at 1, 2, and 4 hpi. Our results suggest that TroMIF is an essential effector of the innate immune system and plays a pivotal role in antibacterial immunity.

MIF inhibitor ISO-1 alleviates severe acute pancreatitis-associated acute kidney injury by suppressing the NLRP3 inflammasome signaling pathway

BACKGROUND

Acute kidney injury (AKI) is an important complication of severe acute pancreatitis (SAP) with a poor prognosis. The methyl ester of (S,R)-3-(4-hydroxyphenyl)-4,5-dihydro-5-isoxazole acetic acid (ISO-1), an inhibitor of macrophage migration inhibitory factor (MIF), has protective effects against many diseases. Our previous study confirmed MIF inhibition alleviated SAP. Here, we explored the effects of ISO-1 in an experimental mouse model of SAP-associated AKI induced by l-arginine.

METHODS

Mice were randomly divided into four treatment groups (n = 6 each): control (CON), SAP, SAP + ISO-1, and ISO-1. Histopathologic examination was used to observe damage in pancreatic and renal tissues. Biochemical and enzyme-linked immunosorbent assays (ELISA) kits were used to measure the serologic indicators amylase, lipase, creatinine, uric acid, interleukin (IL)-6, and tumor necrosis factor (TNF)-α. Immunohistochemistry was used to detect protein expression of NLRP3, ASC and caspase-1, and the infiltration of myeloperoxidase (MPO)-positive neutrophils in kidney tissue. Western blotting was used to detect NLRP3, ASC and caspase-1 and IL-1β protein expression, and real-time PCR was used to measure MIF, IL-6, TNF-α, IL-1β and IL-18 mRNA levels in kidney tissue.

RESULTS

ISO-1 treatment alleviated pathological damage in pancreatic and renal tissues, and reduced the serum levels of amylase, lipase, creatinine, uric acid, IL-6 and TNF-α. ISO-1 also reduced protein expression of NLRP3, ASC, caspase-1 and IL-1β, mRNA expression of MIF, IL-6, TNF-α, IL-1β and IL-18, and the infiltration of MPO-positive neutrophils in kidney tissue.

CONCLUSION

ISO-1 has a protective effect against experimental SAP-associated AKI. And the mechanism may be associated with ISO-1 inhibiting NLRP3 inflammasome signaling pathway.

Targeting Macrophage Migration Inhibitory Factor in Acute Pancreatitis and Pancreatic Cancer

Macrophage migration inhibitory factor (MIF) is a pleiotropic cytokine implicated in the pathogenesis of inflammation and cancer. It is produced by various cells and circulating MIF has been identified as a biomarker for a range of diseases. Extracellular MIF mainly binds to the cluster of differentiation 74 (CD74)/CD44 to activate downstream signaling pathways. These in turn activate immune responses, enhance inflammation and can promote cancer cell proliferation and invasion. Extracellular MIF also binds to the C-X-C chemokine receptors cooperating with or without CD74 to activate chemokine response. Intracellular MIF is involved in Toll-like receptor and inflammasome-mediated inflammatory response. Pharmacological inhibition of MIF has been shown to hold great promise in treating inflammatory diseases and cancer, including small molecule MIF inhibitors targeting the tautomerase active site of MIF and antibodies that neutralize MIF. In the current review, we discuss the role of MIF signaling pathways in inflammation and cancer and summarize the recent advances of the role of MIF in experimental and clinical exocrine pancreatic diseases. We expect to provide insights into clinical translation of MIF antagonism as a strategy for treating acute pancreatitis and pancreatic cancer.

Macrophage migration inhibitory factor is an early marker of severe acute pancreatitis based on the revised Atlanta classification

BACKGROUND

Various serum markers for early identification of severe acute pancreatitis (SAP) have been studied. Serum macrophage migration inhibitory factor (MIF) was reported to be correlated with severity of acute pancreatitis (AP) based on the 1992 Atlanta classification. However, MIF has never been proven to be predictive of disease severity based on the revised Atlanta classification (RAC). The potential predictive value of MIF needs to be further validated.

METHODS

Consecutive patients with AP within 48 h after symptom onset and 10 healthy control volunteers were enrolled prospectively. Serum MIF levels were measured by enzyme-linked immunosorbent assay (ELISA). The predictive value of MIF, clinical scores and other serum markers were determined.

RESULTS

Among 143 patients with AP, there were 52 (36.4%), 65 (45.5%) and 26 (18.1%) with mild, moderate and severe disease based on the RAC respectively. Compared with healthy volunteers, serum levels of MIF were significantly higher in AP patients, especially those with SAP (P < 0.001). Multivariate regression analysis indicated that increased serum MIF (cut-off 2.30 ng/ml, OR = 3.16, P = 0.008), IL-6 (cut-off 46.8 pg/ml, OR = 1.21, P = 0.043), APACHE II score (cut-off 7.5, OR = 2.57, P = 0.011) and BISAP score (cut-off 1.5, OR = 1.01, P = 0.038) were independent risk factors for predicting SAP (P < 0.05). By using the area under the receiver operating characteristic (ROC) curve (AUC), MIF (AUC 0.950) demonstrated more excellent discriminative power for predicting SAP than APACHE II (AUC 0.899), BISAP (AUC 0.886), and IL-6 (AUC 0.826).

CONCLUSIONS

Serum MIF is a valuable early marker for predicting the severity of AP based on the RAC.

Overview and prospect of serum markers for early prediction of severity of acute pancreatitis

Acute pancreatitis (AP) is one of the most common and potentially fatal emergencies of the digestive system. Aseptic inflammation of the pancreas caused by self-digestion of trypsin is considered to be the main pathogenesis of AP. The clinical course and prognosis of AP with different degrees of severity vary greatly, so early prediction of the severity of AP is of great significance to the diagnosis and treatment of this disease. In recent years, great progress has been made in the early risk assessment and severity stratification of AP patients with serum markers. This article gives an overview and discuss the prospects of serum markers for early prediction of the severity of AP.

Macrophage inhibitory factor (MIF) gene polymorphisms are associated with disease susceptibility and with circulating MIF levels in active non-segmental vitiligo in patients from western Mexico

Background

The macrophage migration inhibiting factor (MIF) is a protein that promotes the activation of immune cells and the production of other proinflammatory cytokines such as TNF‐α, IL‐1β, and IFN‐γ, which have proposed to play an essential role in the pathogenesis of vitiligo. The study aimed to assess the association between MIF polymorphisms (−794 CATT_5‐8 and −173 G>C), MIF in situ expression, and MIF serum concentrations with susceptibility and disease activity in patients with non‐segmental vitiligo (NSV) from western Mexico.

Methods

The study included 111 patients with NSV and 201 control subjects. Genotyping was performed by conventional PCR (−794 CATT_5‐8) and PCR‐RFLP (−173 G>C) methods. MIF mRNA expression was quantified by real‐time PCR and MIF serum concentrations were determined by ELISA kit. Histopathological samples were analyzed by automated immunohistochemistry.

Results

The MIF polymorphisms were associated with NSV susceptibility. Serum concentrations of MIF were higher in patients with active NSV and correlated negatively with the years of evolution. The depigmented skin from patients with active vitiligo showed a high expression of MIF.

Conclusion

MIF polymorphisms increase the risk of NSV in the western Mexican population. The serum concentrations of MIF and in situ expression are associated with active NSV.

Inhibition of macrophage migration inhibitory factor prevents thyroid dysfunction in pregnant rats with acute pancreatitis

Acute pancreatitis during pregnancy (APIP) rarely occurs but may lead to preterm delivery and be associated with high fetal mortality. Macrophage migration inhibitory factor (MIF) participates in various inflammatory diseases as a pro-inflammatory cytokine. In this study, we aimed to explore the effects of (S, R)-3-(4-hydroxyphenyl)-4, 5dihydro-5-isoxazole acetic methyl ester (ISO-1), an inhibitor of MIF, on maternal thyroid injury associated with APIP and its potential mechanisms in a pregnant rat model. APIP model was induced by retrograde injection of sodium taurocholate. ISO-1 was injected intraperitoneally 30 min before model establishment. The severity of pancreatitis was assessed by levels of tumor necrosis factor (TNF)‑α, interleukin (IL)‑1β, IL-6 of maternal serum as well as histopathological score. Thyroid injury was determined by free triiodothyronine (FT3), free tetraiodothyronine (FT4) and thyroid histopathological score. Levels of MIF in maternal serum and the expression of MIF, CD68, CD3 and intercellular cell adhesion molecule-1 (ICAM-1) as well as oxidative stress status in maternal thyroid tissues were detected. Ultrastructure of maternal thyroid tissues was observed by transmission electron microscope. Thyroid injuries occurred in APIP and the lesions were attenuated with the pretreatment of ISO-1. Moreover, ISO-1 reduced the expression of MIF, attenuated the activations of CD68, CD3, ICAM-1 while improved oxidative stress status in maternal thyroid. Our research suggested a protective role of ISO-1 on thyroid injury and endocrine disorder during APIP, which may be associated with the inhibition of biological functions of MIF.

Macrophage Migration Inhibitor Promoted the Intrahepatic Bile Duct Injury in Rats with Severe Acute Pancreatitis

BACKGROUND

Macrophage migration inhibitory factor (MIF) is involved in many acute and chronic inflammatory diseases. However, its role in intrahepatic bile duct (IBD) cell damage associated with severe acute pancreatitis (SAP) remains unclear.

AIMS

This study was aimed to identify the role of MIF and its underlying mechanisms in SAP complicated by IBD cell damage.

METHODS

Forty-eight specific-pathogen-free male Wistar rats were randomly divided into four groups (N = 12): a sham operation group (SO group) and three SAP model groups (SAP-3h, SAP-6h, and SAP-12h). Immunohistochemistry was used to detect the expression of MIF and P38 in IBD cells. MIF mRNA expression in IBD cells was observed using real-time fluorescent quantitative polymerase chain reaction (real-time PCR). In addition, Western blotting was performed to detect the protein expression of P38, phosphorylated P38 (P-P38), nuclear factor-κB (NF-κB p65), and tumor necrosis factor alpha (TNF-α). Enzyme-linked immunosorbent assays were used to analyze the levels of TNF-α, IL-1β, and IL-6 in the IBD of rats.

RESULTS

Compared with the SO group, the expression of MIF in the IBD was significantly upregulated both at mRNA and at protein levels in the SAP group. Besides, the protein expression levels of P38, P-P38, NF-κB, p65, TNF-α, IL-1β, and IL-6 in the IBD in rats were also significantly increased in the SAP group and the levels increased gradually as acute pancreatitis progressed (all P < 0.05).

CONCLUSIONS

MIF may promote the IBD injury and inflammatory reaction in SAP via activating the P38-MAPK and NF-κB signaling pathways.

Serum levels of tumor necrosis factor-like weak inducer of apoptosis (TWEAK) in predicting the severity of acute pancreatitis

INTRODUCTION

Acute pancreatitis (AP) is a severe disease associated with significant morbidity and mortality. The overall outcome has improved, but specific treatment(s) remains elusive. The challenge is the early identification and treatment of patients who will develop severe acute pancreatitis. Therefore, the aim of the present study is to investigate plasma levels of tumor necrosis factor-like weak inducer of apoptosis (TWEAK) in the initial phase of predicted severe acute pancreatitis.

METHODS

Between June 2014 and January 2016, 64 patients with acute pancreatitis and 36 healthy individuals were included to study. Four blood samples, for serum TWEAK measurement, were taken from each individual in each group. The first measurement was taken from the admission blood sample. The subsequent three samples were taken at 12, 24, and 48 h after the hospital admission.

RESULTS

Serum TWEAK levels were significantly higher in patients with acute pancreatitis when compared with healthy controls. TWEAK plasma concentrations in severe pancreatitis patients were significantly higher than in mild pancreatitis patients.

CONCLUSION

Serum TWEAK levels increase progressively with the severity of acute pancreatitis and TWEAK might be a novel early marker of severity in acute pancreatitis.

Macrophage migration inhibitory factor antagonist (S,R)3‑(4‑hydroxyphenyl)‑4,5‑dihydro‑5‑isoxazole acetic acid methyl ester attenuates inflammation and lung injury in rats with acute pancreatitis in pregnancy

Macrophage migration inhibitory factor (MIF) is an inflammatory cytokine involved in many acute and chronic inflammatory diseases. However, its role in acute lung injury associated with acute pancreatitis in pregnancy (APIP) has not yet been elucidated. The present study was undertaken to clarify the effect and potential mechanism of MIF antagonist (S,R)3‑(4‑hydroxyphenyl)‑4,5‑dihydro‑5‑isoxazole acetic acid methyl ester (ISO‑1) in the development of acute lung injury in rats with APIP. Eighteen late‑gestation SD rats were randomly assigned to three groups: Sham operation (SO) group, APIP group, and ISO‑1 group. All the rats were sacrificed 6 h after modeling. The severity of pancreatitis was evaluated by serum amylase (AMY), lipase (LIPA), tumor necrosis factor (TNF)‑α, interleukin (IL)‑1β and IL‑6 and assessing the histopathological score. Lung injury was determined by performing histology and inflammatory cell infiltration investigations. Western blot analysis was used to detect the protein expression of MIF, phosphorylated and total P38 and nuclear factor‑κB (NF‑κB) protein in lungs. The results showed that MIF was upregulated in the lung of APIP rats. Compared with APIP group, the intervention of ISO‑1 alleviated the pathological injury of the pancreas and lungs, decreased serum AMY and LIPA, attenuated serum concentrations of TNF‑α, IL‑1β, and IL‑6, reduced the number of MPO‑positive cells in the lung and inhibited the activation of P38MAPK and NF‑κB. These results suggest that MIF is activated in lung injury induced by APIP. Furhtermore, the present findings indicate that the MIF antagonist ISO‑1 has a protective effect on lung injury and inflammation, which may be associated with deactivating the P38MAPK and NF‑κB signaling pathway.

Fetal liver injury ameliorated by migration inhibitory factor inhibition in a rat model of acute pancreatitis in pregnancy

AIM

This study was designed to investigate and assess fetal liver injury in a rat model of acute pancreatitis in pregnancy (APIP) as well as its possible mechanisms and potential therapeutic targets.

METHODS

The APIP model was induced by sodium taurocholate in Sprague-Dawley rats during the third trimester. ISO-1, a macrophage migration inhibitory factor (MIF) antagonist, was given before the induction of APIP. In addition, sham-operated rats at later gestation were set as controls. Histological changes in the fetal liver and maternal pancreas were assessed. Amylase and lipase activity as well as the levels of tumor necrosis factor (TNF)-α and interleukin (IL)-1β were examined. The expression of MIF in fetal liver was determined by immunochemistry and the expression of NF-κB, IκBα, high mobility group box-1 protein (HMGB1), TNF-α, and IL-1β in fetal liver was determined by Western blot analysis. Ultrastructures of hepatic cells in fetal rats were observed under transmission electron microscopy.

RESULTS

ISO-1 ameliorated the following: (i) pathological injuries in maternal pancreas and fetal liver; (ii) levels of TNF-α and IL-1β in maternal serum; and (iii) levels of MIF, myeloperoxidase, NF-κB, HMGB1, TNF-α, and IL-1β in fetal liver.

CONCLUSION

Pathological damage and an inflammatory response in fetal liver were induced by APIP, and MIF inhibition ameliorated fetal liver injury by inhibiting the inflammatory cascade.

Genetic Polymorphisms: A Novel Perspective on Acute Pancreatitis

Acute pancreatitis (AP) is a complex disease that results in significant morbidity and mortality. For many decades, it has compelled researchers to explore the exact pathogenesis and the understanding of the pathogenesis of AP has progressed dramatically. Currently, premature trypsinogen activation and NF-κB activation for inflammation are two remarkable hypotheses for the mechanism of AP. Meanwhile, understanding of the influence of genetic polymorphisms has resulted in tremendous development in the understanding of the advancement of complex diseases. Now, genetic polymorphisms of AP have been noted gradually and many researchers devote themselves to this emerging area. In this review, we comprehensively describe genetic polymorphisms combined with the latest hypothesis of pathogenesis associated with AP.

Increased admission serum cold-inducible RNA-binding protein concentration is associated with prognosis of severe acute pancreatitis

BACKGROUND

Cold-inducible RNA-binding protein (CIRP) is a pro-inflammatory cytokine. This study assessed its relation to disease severity and major adverse events (namely local complications, organ failure and in-hospital mortality) of severe acute pancreatitis (SAP) and its discriminatory ability for SAP.

METHODS

This prospective and observational study recruited a total of 102 SAP patients, 48 patients with mild acute pancreatitis and 102 healthy individuals. Serum CIRP concentrations were determined using enzyme-linked immunosorbent assay.

RESULTS

Serum CIRP concentrations were significantly higher in patients compared to controls. Serum CIRP concentrations were highly correlated with the circulating concentrations of common inflammatory mediators (i.e., procalcitonin, C-reactive protein and white blood cell) and the traditional predictors of disease severity (namely Acute Physiology and Chronic Health Care Evaluation II score, Ranson score, multiple organ dysfunction score and sequential organ failure assessment score). CIRP in serum was an independent predictor for major adverse events. Serum CIRP concentrations showed high predictive value for major adverse events, and possessed high discriminatory performance for SAP. Moreover, its effects significantly exceeded those of the preceding inflammatory mediators.

CONCLUSIONS

Increased serum CIRP concentrations clearly reflect SAP severity and prognosis and significantly distinguish SAP, substantializing CIRP as a potential SAP biomarker.

Role of Biomarkers in Diagnosis and Prognostic Evaluation of Acute Pancreatitis

Acute pancreatitis is a potentially life threatening disease. The spectrum of severity of the illness ranges from mild self-limiting disease to a highly fatal severe necrotizing pancreatitis. Despite intensive research and improved patient care, overall mortality still remains high, reaching up to 30–40% in cases with infected pancreatic necrosis. Although little is known about the exact pathogenesis, it has been widely accepted that premature activation of digestive enzymes within the pancreatic acinar cell is the trigger that leads to autodigestion of pancreatic tissue which is followed by infiltration and activation of leukocytes. Extensive research has been done over the past few decades regarding their role in diagnosis and prognostic evaluation of severe acute pancreatitis. Although many standalone biochemical markers have been studied for early assessment of severity, C-reactive protein still remains the most frequently used along with Interleukin-6. In this review we have discussed briefly the pathogenesis and the role of different biochemical markers in the diagnosis and severity evaluation in acute pancreatitis.

Soluble CD163 is increased in patients with acute pancreatitis independent of disease severity

Macrophages are crucially involved in the pathophysiology of acute pancreatitis. Soluble CD163 (sCD163) is specifically released from macrophages and systemic levels are increased in inflammatory diseases. Here, sCD163 was measured in serum of 50 patients with acute pancreatitis to find out possible associations with disease activity. Admission levels of systemic sCD163 were nearly three-fold higher in patients with acute pancreatitis compared to controls. In patients sCD163 did not correlate with C-reactive protein and leukocyte count as established markers of inflammation. Levels were not associated with disease severity assessed by the Schroeder score, Balthazar score, Acute Physiology, Age, and Chronic Health Evaluation (Apache) II score and peripancreatic necrosis score. Soluble CD163 was not related to complications of acute pancreatitis. These data show that serum sCD163 is increased in acute pancreatitis indicating activation of macrophages but is not associated with disease severity and outcome.

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.

Severity markers in patients with acute pancreatitis

To evaluate the effectiveness of serum levels of resistin and CD14 expression in monocytes, and high-sensitivity C-reactive protein (hsCRP) in early stages of acute pancreatitis and correct prediction of the severity of acute pancreatitis (AP) using scoring systems. The study involved 10 (29.41%) male and 24 (70.59%) female patients (total n=34) followed for AP diagnosis at the Department of General Surgery, Ataturk University Medical School between July 2008 and September 2009. In all the patients, Ranson and APACHE II scores, serum resistin, hsCRP, and monocyte CD14 expression levels were determined. The patients were divided into two groups as mild and severe AP groups. A control group was formed and the intergroup comparisons were made. Values ≥ 3 based on the Ranson scoring scale and values ≥ 8 in APACHE II scoring scale were considered to indicate severe AP. Evaluations were based on the values obtained on the 1st and 7th days for serum resistin and hsCRP levels and monocyte CD 14 expression. In 17 (50%) patients, severe AP was determined. No statistically significant differences were found between the mean serum resistin levels of AP groups, while the difference for the same parameter between the mild and severe AP groups and the control group was statistically significant. In the severe AP group, the mean 1st day and 7th day serum hsCRP levels were statistically significantly higher. The CD14 expression in monocytes was similar in all the groups. Serum hsCRP concentrations and Ranson and APACHE II scores and serum resistin and hsCRP concentrations on the 1st day were positively correlated. Serum hsCRP measurement is effective in determining the severity of acute pancreatitis. Serum resistin measurement may be a useful early marker in determining the inflammatory response in AP. However, CD14 expression in monocytes was not found to be a useful marker in the diagnosis and prediction of the disease severity in AP patients.

Plasma copeptin levels are associated with prognosis of severe acute pancreatitis

Copeptin reflects the individual stress level, and is correlated with outcomes of critical illness. This study was designed to evaluate its relationship with disease severity, local complications, organ failure and mortality of severe acute pancreatitis (SAP). Seventy-eight SAP patients and 78 sex- and age-matched healthy individuals were recruited. Plasma samples were obtained on admission from SAP patients and at study entry from healthy individuals. Copeptin concentration was determined using enzyme-linked immunosorbent assay. Plasma copeptin level was obviously higher in patients than in healthy individuals, was identified as an independent predictor of local complications, organ failure and in-hospital mortality, was highly associated with traditional predictors of disease severity and mortality including the Acute Physiology and Chronic Health Care Evaluation II score, Ranson score, multiple organ dysfunction score, sequential organ failure assessment score, and predicted local complications, organ failure, and in-hospital mortality of SAP patients with high areas under receiver operating characteristic curve. Furthermore, its predictive value was similar to the traditional predictors'. However, it could not improve these traditional predictors' predictive values. Therefore, increased plasma copeptin level is associated with disease severity and identified as a novel prognostic marker of local complications, organ failure and mortality after SAP.

Copeptin is a predictive biomarker of severity in acute pancreatitis

BACKGROUND

Acute pancreatitis remains a common intraabdominal disease with a complex pathophysiology. The overall outcome has improved, but specific treatment remains elusive. The challenge is the early identification and treatment of patients who will develop severe acute pancreatitis. Therefore, the aim of the present study is to investigate plasma levels of copeptin in the initial phase of predicted severe acute pancreatitis.

METHODS

Between August 2008 and December 2011, 57 patients with acute pancreatitis and 30 healthy individuals were included in the study. Four blood samples, for serum copeptin measurement, were taken from each individual in each group. The first measurement was taken from the admission blood sample. The subsequent 3 samples were taken at 12, 24, and 48 hours after the onset of pain.

RESULTS

Copeptin plasma concentrations were significantly higher in patients with acute pancreatitis when compared with healthy controls. Copeptin plasma concentrations in severe pancreatitis patients were significantly higher than in mild pancreatitis patients.

CONCLUSIONS

Copeptin plasma concentrations were significantly higher in patients with acute pancreatitis when compared with healthy controls. Copeptin plasma concentrations in severe pancreatitis patients were significantly higher than in mild pancreatitis patients.

Beta cell function: the role of macrophage migration inhibitory factor

During evolution, beta cells adapted to a sole aim: the production and stimulus-dependent secretion of insulin. This acquired specificity was accompanied by a loss of protection mechanisms predisposing beta cell to a high vulnerability. Among beta cell-damaging molecules, a new one has been identified recently: macrophage migration inhibitory factor (MIF). MIF was at first designated as a T-cell product that inhibits random movement of macrophages. Over the years, the number of functions attributed to this protein increased significantly, positioning MIF at the top of inflammatory cascade in the combat against infection and in immunoinflammatory and autoimmune diseases. This exceptionally versatile molecule regulates insulin secretion in physiological conditions, while in pathological states it alters beta cell function and induces their apoptosis or necrosis and affects beta cell neoplasia.

Pancreatic nociception--revisiting the physiology and pathophysiology

BACKGROUND

Pain management of many pancreatic diseases remains a major clinical concern. This problem reflects our poor understanding of pain signaling from the pancreas.

OBJECTIVES

This review provides an overview of our current knowledge, with emphasis on current pain management strategies and recent experimental findings.

METHODS

A systematic search of the scientific literature was carried out using EMBASE, PubMed/MEDLINE, and the Cochrane Central Register of Controlled Trials for the years 1965-2011 to obtain access to all publications, especially randomized controlled trials, systematic reviews, and meta-analyses exploring pain and its management in disease states such as acute pancreatitis (AP), chronic pancreatitis (CP) and pancreatic cancer (PC).

RESULTS

Over the last decade, numerous molecular mediators such as nerve growth factor and the transient receptor potential (TRP) cation channel family have been implicated in afferent nerve signaling. More recent animal studies have indicated the location of the receptive fields for the afferent nerves in the pancreas and shown that these are activated by agents including cholecystokinin octapeptide, 5-hydroxytryptamine and bradykinin. Studies with PC specimens have shown that neuro-immune interactions occur and numerous agents including TRP cation channel V1, artemin and fractalkine have been implicated. Experimental studies in the clinical setting have demonstrated impairment of inhibitory pain modulation from supraspinal structures and implicated neuropathic pain mechanisms.

CONCLUSIONS

Our knowledge in this area remains incomplete. Characterization of the mediators and receptors/ion channels on the sensory nerve terminals are required in order to facilitate the development of new pharmaceutical treatments for AP and CP.

Up-regulated expression of MIF by interfacial membrane fibroblasts and macrophages around aseptically loosened implants

BACKGROUND

Local chronic inflammatory reaction plays an important role in the process of aseptic loosening of implants after total joint replacement. In addition, macrophage migration inhibitory factor (MIF) is a key upstream regulator of inflammation, and it is a significant regulator of inflammatory diseases. The purpose of this study is to investigate if the fibroblasts and macrophages in the interfacial membranes overexpress MIF.

MATERIALS AND METHODS

The 15 tissue samples of interfacial membranes were obtained from the tissues around the aseptically loosened femoral implants adjacent to osteolytic lesion in 15 patients. The 15 control synovial samples of hip joints were obtained from 15 patients who underwent primary hip arthroplasty because of the fresh fracture of the femoral neck. The levels of MIF protein and mRNA were evaluated by ELISA assay, immunofluorescence labeling, and real-time RT-PCR. Fibroblasts and macrophages were identified by immunofluorescence labeling.

RESULTS

The levels of MIF protein and mRNA were significantly increased, as well as the numbers of MIF+ fibroblasts and macrophages in the interfacial membranes compared with the control synovium.

CONCLUSION

Not only the macrophages, but also the fibroblasts in interfacial membranes overexpress MIF. MIF may play a significant role in the process of aseptic-loosening implants after total joint replacement.

Diagnostic validity of serum macrophage inhibitor cytokine and tissue polypeptide-specific antigen in pancreatobiliary diseases

BACKGROUND AND AIM

Macrophage inhibitory cytokine (MIC-1) and tissue polypeptide-specific antigen (TPS) are novel markers for several inflammatory and malignant disorders, and there are no sufficient data about the utility of these antigens as serum tumor markers. We aimed at measuring the serum levels of MIC-1 and TPS in patients with benign and malignant pancreatobiliary diseases and at determining their diagnostic efficacy.

PATIENTS AND METHODS

Sera collected from patients with pancreatic adenocarcinomas (56 cases), periampullary carcinomas other than pancreatic carcinomas (15 cases), benign pancreatic diseases (31 cases), benign biliary diseases (15 cases) and healthy volunteers (33 cases) were analyzed for MIC-1 and TPS and the results were compared with CA 19-9.

RESULTS

Serum MIC-1 levels increased more significantly in patients with pancreatic carcinomas than in patients with benign pancreatobiliary diseases and healthy controls (p < 0.05). MIC-1 has a similar sensitivity (81%) but a lower specificity (73 vs. 97%) than CA 19-9 in patients with pancreatic carcinomas. Serum TPS was comparable among patients with malignant and benign pancreatobiliary diseases, and healthy controls.

CONCLUSION

MIC-1 is a valuable tumor marker for the diagnosis of pancreatic cancer. It has a good correlation with CA 19-9. TPS has no diagnostic importance to differentiate pancreatobiliary diseases. and IAP.

Macrophage migration inhibitory factor (MIF): a promising biomarker

Macrophage migration inhibitory factor (MIF) is an immunoregulatory cytokine, the effect of which on arresting random immune cell movement was recognized several decades ago. Despite its historic name, MIF also has a direct chemokine-like function and promotes cell recruitment. Multiple clinical studies have indicated the utility of MIF as a biomarker for different diseases that have an inflammatory component; these include systemic infections and sepsis, autoimmune diseases, cancer, and metabolic disorders such as type 2 diabetes and obesity. The identification of functional promoter polymorphisms in the MIF gene (MIF) and their association with the susceptibility or severity of different diseases has not only served to validate MIF's role in disease development but also opened the possibility of using MIF genotype information to better predict risk and outcome. In this article, we review the clinical data of MIF and discuss its potential as a biomarker for different disease applications.

Value of the different prognostic systems and biological markers for predicting severity and progression of acute pancreatitis

OBJECTIVE

Several tools have been developed for severity stratification in acute pancreatitis (AP). They include single biochemical markers and complex scoring systems, all of which aim at an early detection of severe AP to optimize monitoring and treatment of these patients. The aim of this study was to reassess and compare the value of some known and newly-introduced prognostic markers in the clinical context.

MATERIAL AND METHODS

We have conducted a prospective observational study. One hundred and eight patients with a diagnosis of AP and onset of the disease within last 72 h were included in this study. Clinical data and expression results of some serum biochemical markers were used for statistical analysis. The diagnostic performance of scores predicting severity and progression of AP, cut-off values, specificity, and sensitivity were established using receiver operating characteristic curve analysis.

RESULTS

Among single biochemical markers, C-reactive protein remains the most useful. Despite its delayed increase, it is accurate, cheap, and widely available. Interleukin-6 and macrophage migration inhibitory factor seem to be new promising parameters for use in clinical routine. Pancreas specific scores (Imrie-Glasgow, pancreatitis outcome prediction) and scores assessing organ dysfunction (acute physiology and chronic health evaluation II, multiple organ dysfunction score, and Marshall score) remain of value in determining the severity, complications, and possible outcome of AP.

CONCLUSIONS

Indication, timing, and consequences of the methods applied need to be carefully considered and incorporated into clinical assessments. Currently, there is no single prognostic marker that would cover the whole range of problems associated with the treatment of AP. The prediction of severity and progression of AP can be achieved using a series of accurate methods. The decision to undertake interventional or surgical treatment is the most complex task requiring both clinical judgment and meticulous monitoring of the patient.

Different profiles of cytokine expression during mild and severe acute pancreatitis

AIM

To study secretion patterns of pro- and anti-inflammatory cytokines, and activation of various cellular subsets of leukocytes in peripheral blood.

METHODS

We have conducted a prospective observational study. One hundred and eight patients with a diagnosis of acute pancreatitis and onset of the disease within last 72 h were included in this study. The mRNA expression of 25 different types of cytokines in white blood cells was determined by quantitative real time polymerase chain reaction. Levels of 8 different cytokines in blood serum were measured by enzyme linked immunosorbent assay. Clinical data and cytokine expression results were subjected to statistical analysis.

RESULTS

Severe and necrotizing acute pancreatitis (AP) is characterized by the significant depletion of circulating lymphocytes. Severe acute pancreatitis is associated with a typical systemic inflammatory response syndrome and over-expression of pro-inflammatory cytokines [interleukin (IL)-6, IL-8, macrophage migration inhibitory factor (MIF)]. Serum IL-6 and MIF concentrations are the best discriminators of severe and necrotizing AP as well as possible fatal outcome during the early course of the disease.

CONCLUSION

Deregulation of cellular immune system is a key event leading to severe and necrotizing AP. IL-6 and MIF could be used as early predictors of complications.

-651C/T promoter polymorphism in the CD14 gene is associated with severity of acute pancreatitis in Japan

PURPOSE

This study aimed to clarify the association of the promoter variants in the CD14 gene with pancreatic diseases in Japan.

METHODS

Three hundred forty-six unrelated patients with acute pancreatitis (AP) (107 with severe and 239 with mild), 263 patients with chronic pancreatitis (CP), 264 patients with pancreatic neoplasm, and 319 healthy controls were genotyped for the single nucleotide polymorphisms at positions -260 and -651 from the AUG start codon in the CD14 gene by polymerase chain reaction-restriction enzyme digestion.

RESULTS

The allele and genotype frequencies of the -260C/T and -651C/T polymorphisms did not differ between controls and patients with AP. In subgroup analyses, patients with severe AP had more -651C allele than controls [P = 0.005; odds ratio (OR) 1.71; 95% confidence interval (CI) = 1.18-2.49] or patients with mild AP (P = 0.001; OR 1.95; 95% CI = 1.33-2.85). Genotype -651CC was more common (P = 0.001 vs. controls and P = 0.001 vs. mild AP), and -651CT was less (P = 0.009 vs. controls and P = 0.007 vs. mild AP) in patients with severe AP than in healthy controls or patients with mild AP. The frequencies of pseudocyst development and requirement of surgery were higher in AP patients with -651CC than in those without this genotype. The -260C/T polymorphism was not associated with the severity of AP. The allele and genotype frequencies of both polymorphisms did not differ between controls and patients with CP or pancreatic neoplasm.

CONCLUSION

-651C/T promoter polymorphism in the CD14 gene was associated with severity of AP in Japan.

Prediction of mortality in acute pancreatitis: a systematic review of the published evidence

OBJECTIVE

In this review, we focus on studies that examined such prognostic indices in relation to predicting a fatal outcome from pancreatitis.

SUMMARY BACKGROUND DATA

Acute pancreatitis (AP) is a common emergency, and early identification of high-risk patients can be difficult. For this reason, a plethora of different prognostic variables and scoring systems have been assessed to see if they can reliably predict the severity of pancreatitis and/or subsequent mortality.

METHODS

All studies that focused on AP, including retrospective series and prospective trials, were retrieved and analysed for factors that could influence mortality. Articles that analysed factors influencing the severity of the disease or the manifestation of disease-related complications were excluded.

RESULTS

58 articles meeting the inclusion criteria were identified. Among the various factors investigated, APACHE II seemed to have the highest positive predictive value (69%). However, most prognostic variables and scores showed high negative predictive values but suboptimal values for positive predictive power.

CONCLUSIONS

Despite the proliferation of scoring systems for grading AP, none are ideal for the prediction of mortality. With the exception of the APACHE II, the other scores and indexes do not have a high degree of sensitivity, specificity and predictive values.

Elevated serum creatinine as a marker of pancreatic necrosis in acute pancreatitis

OBJECTIVES

Pancreatic necrosis is a serious complication of acute pancreatitis. The identification of simple laboratory tests to detect subjects at risk of pancreatic necrosis may direct management and improve outcome. This study focuses on the association between routine laboratory tests and the development of pancreatic necrosis in patients with acute pancreatitis.

METHODS

In a cohort of 185 patients with acute pancreatitis prospectively enrolled in the Severity of Acute Pancreatitis Study, patients with contrast-enhanced computerized tomography performed were selected (n=129). Serum hematocrit, creatinine, and urea nitrogen on admission and peak values within 48 h of admission were analyzed. The volume of intravenous fluid resuscitation was calculated for each patient.

RESULTS

Of 129 patients, 35 (27%) had evidence of pancreatic necrosis. Receiver operating characteristic curves for pancreatic necrosis revealed an area under the curve of 0.79 for admission hematocrit, 0.77 for peak creatinine, and 0.72 for peak urea nitrogen. Binary logistic regression yielded that all three tests were significantly associated with pancreatic necrosis (P<0.0001), with the highest odds ratio, 34.5, for peak creatinine. The volume of intravenous fluid resuscitation was similar in patients with and without necrosis. Low admission hematocrit (< or =44.8%) yielded a negative predictive value of 89%; elevated peak creatinine (>1.8 mg/dl) within 48 h yielded a positive predictive value of 93%.

CONCLUSIONS

We confirm that a low admission hematocrit indicates a low risk of pancreatic necrosis (PNec) in patients with acute pancreatitis. In contrast, an increase in creatinine within the first 48 h is strongly associated with the development of PNec. This finding may have important clinical implications and warrants further investigation.

Advance in laboratory markers of acute severe pancreatitis

Acute pancreatitis (AP) was one of common acute abdominal diseases in digestive system, and it was divided into mild type and severe type. Many methods were used to judge the severity of AP, including all kinds of scoring system, biochemical indexes, and imaging methods. Recent researches found that some serum indexes such as acute reactive proteins, cytokines, enzymes, active peptides and procalcitonin could classify the severity of AP and judge the risks of complications. This article reviews the progress in the laboratory markers of severe AP.

Effects of glucocorticoid agonist and antagonist on the pathogenesis of L-arginine-induced acute pancreatitis in rat

OBJECTIVES

To investigate the consequences of treatment with an exogenous glucocorticoid agonist (methylprednisolone) and antagonist (RU-38486) on the local and systemic responses in L-arginine-induced acute pancreatitis in rats.

METHODS

The methylprednisolone and RU-38486 were administered just before pancreatitis induction. Plasma amylase activity, interleukin 6 activity, pancreatic weight/body weight ratio, plasma macrophage migration inhibitory factor (MIF) concentration, and pancreatic nuclear transcription factor (NF) kappaB activity were determined. The extents of pancreas, liver, and lung injuries were assessed by histology.

RESULTS

Acute pancreatitis resulted in NF-kappaB activation and proinflammatory cytokine release in rats. In the glucocorticoid agonist group, plasma amylase and interleukin 6 levels were significantly decreased as compared with those of RU-38486 and nontreated groups. Antagonist treatment led to significantly higher MIF production at 8 and 12 hours after L-arginine injection as compared with the agonist-treated and nontreated groups. Glucocorticoid agonist treatment significantly decreased the level of NF-kappaB 24 hours after pancreatitis induction. Histological investigations showed protective effect of agonist treatment on acute pancreatitis-induced tissue damage in the pancreas and lung.

CONCLUSIONS

These results corroborated the importance of MIF in acute pancreatitis. The glucocorticoid-dependent mechanisms seem to play a crucial role in the control of the inflammatory response and tissue damage in L-arginine-induced experimental acute pancreatitis.

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.

Predicting mortality in patients with systemic inflammatory response syndrome: an evaluation of two prognostic models, two soluble receptors, and a macrophage migration inhibitory factor

Better outcomes in patients suspected of community-acquired infections requires the optimal and timely assessment of disease severity at the point of first contact with the health care system, which is typically in the emergency department. This study was conducted using a previously described, prospectively collected cohort of patients with systemic inflammatory response syndrome (SIRS) that were admitted to an emergency department and a department of infectious diseases at a university hospital. Plasma samples were collected and disease severity scores calculated upon admission. A multiplex immunoassay and a newly developed enzyme-linked immunosorbent assay (ELISA)-based assay were used to measure the soluble urokinase-type plasminogen activator receptor, soluble triggering receptor expressed on myeloid cells-1, and macrophage migration inhibitory factor. The area under the receiver operating characteristic (ROC) curve for the prediction of 30- and 180-day mortality was used to compare the performance of the markers and the models. A total of 151 patients were eligible for analysis. Of these, nine died before day 30 and 19 died before day 180 post-admission. Admission-soluble urokinase-type plasminogen activator receptor levels were significantly higher in both day 30 and day 180 non-survivors. There was a non-significant trend towards higher macrophage migration inhibitory factor concentrations in day 30 non-survivors. Soluble triggering receptor expressed on myeloid cells-1 levels were significantly lower in non-survivors at both time points. The simplified acute physiology score II (SAPS II) and sequential organ failure assessment (SOFA) scores were significantly higher in non-survivors at both time points, indicating that these models intended for use in intensive care units might also be useful in an emergency department setting.

Prevention of infection following severe acute pancreatitis

PURPOSE OF REVIEW

This review highlights recently reported strategies aimed at quantifying severity of illness earlier in the course of acute pancreatitis and at preventing secondary infection in pancreatic necrosis.

RECENT FINDINGS

New and improved scoring models appear to suggest that the optimal interventional window is between 24 and 72 h of the onset of severe acute pancreatitis. Prospective randomized clinical trials in which patients with severe acute pancreatitis were treated with broad-spectrum antimicrobial regimens as prophylaxis, however, have demonstrated no benefit in terms of preventing late infection in pancreatic necrosis. In contrast, early enteral nutrition with various formulas and supplements, including probiotics, may confer a clinical advantage in terms of morbidity and mortality.

SUMMARY

Continuing to advocate antimicrobial prophylaxis in severe acute pancreatitis is not reasonable, in view of the evidence now available from two large clinical trials. Current guidelines should be revised because of the potential harm to gastrointestinal ecology associated with long-term antibiotic treatment. A suitable alternative way to prevent bacterial overgrowth and secondary infection is lacking, however.