Serum interleukin-15 level is a useful predictor of the complications and mortality in severe acute pancreatitis

Early Predictive Value of Different Indicators for Persistent Organ Failure in Acute Pancreatitis: A Systematic Review and Network Meta-Analysis

GOALS

In this study, we conducted this network meta-analysis (based on the ANOVA model) to evaluate the predictive efficacy of each early predictor.

BACKGROUND

Persistent organ failure (POF) is one of the determining factors in patients with acute pancreatitis (AP); however, the diagnosis of POF has a long-time lag (>48 h). It is of great clinical significance for the early noninvasive prediction of POF.

STUDY

We conducted a comprehensive and systematic search in PubMed, Cochrane library, Embase, and Web of Science to identify relevant clinical trials, case-control studies, or cohort studies, extracted the early indicators of POF in studies, and summarized the predictive efficacy of each indicator through network meta-analysis. The diagnostic odds ratio (DOR) was used to rank the prediction efficiency of each indicator.

RESULTS

We identified 23 studies in this network meta-analysis, including 10,393 patients with AP, of which 2014 patients had POF. A total of 10 early prediction indicators were extracted. The mean and 95% CI lower limit of each predictive indicator were greater than 1.0. Albumin had the largest diagnostic odds ratio, followed by high-density lipoprotein-cholesterol (HDL-C), Ranson Score, beside index for severity in acute pancreatitis Score, acute physiology and chronic health evaluation II, C-reactive protein (CRP), Interleukin 6 (IL-6), Interleukin 8 (IL-8), Systemic Inflammatory Response Syndrome (SIRS) and blood urea nitrogen.

CONCLUSIONS

Albumin, high-density lipoprotein-cholesterol, Ranson Score, and beside index for severity in acute pancreatitis Score are effective in the early prediction of POF in patients with AP, which can provide evidence for developing effective prediction systems. However, due to the limitations of the extraction method of predictive indicators in this study, some effective indicators may not be included in this meta-analysis.

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.

IL-15 regulates fibrosis and inflammation in a mouse model of chronic pancreatitis

Pancreatitis is an inflammatory disease characterized by the induction of several proinflammatory cytokines like interleukin (IL)-6, IL-8, IL-1β, and IL-1. Recently, the multifunctional innate cytokine IL-15 has been implicated in the protection of several diseases, including cancer. Tissue fibrosis is one of the major problems in successfully treating chronic pancreatitis pathogenesis. Therefore, we tested the hypothesis that recombinant IL-15 (rIL-15) treatment may induce innate tissue responses and its overexpression will improve the pathogenesis of cerulein-induced chronic pancreatitis, associated remodeling, and fibrosis. We observed atrophy of acinar cells, increased inflammation, and increased deposition of perivascular collagen, the upregulated protein level of transforming growth factor (TGF)-β1, α-smooth muscle actin (α-SMA), and collagen-1 in cerulein-induced chronic pancreatitis in mice. Furthermore, we reported that rIL-15 treatment protects mice from the cerulein-induced chronic pancreatitis pathogenesis, including acinar cell atrophy, and perivascular accumulation of tissue collagen followed by downregulation of profibrotic genes such as TGF-β1, α-SMA, collagen-1, collagen-3, and fibronectin in cerulein-induced chronic pancreatitis in mice. Mechanistically, we show that IL-15-mediated increase of interferon-γ-responsive invariant natural killer T (iNKT) cells in the blood and tissue protects cerulein-induced pancreatic pathogenesis in mice. Of note, a reduction in iNKT cells was also observed in human chronic pancreatitis compared with normal individuals. Taken together, these data suggest that IL-15 treatment may be a novel therapeutic strategy for treating chronic pancreatitis pathogenesis. NEW & NOTEWORTHY Pancreatic fibrosis is a major concern for the successful treatment of chronic pancreatitis and pancreatic cancer. Therefore, restriction in the progression of fibrosis is the promising approach to manage the pancreatitis pathogenesis. Herein, we present in vivo evidences that pharmacological treatment of recombinant interleukin-15 improves remodeling and fibrosis in cerulein-induced chronic pancreatitis in mice. Our observations indicate that interleukin-15 immunotherapy may be a possible and potential strategy for restricting the progression of fibrosis in chronic pancreatitis.

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.

Brain interleukin-15 in neuroinflammation and behavior

Interleukin (IL)-15 is a ubiquitously expressed cytokine existing in both intracellular and secretory forms. Here we review the expression, regulation, and functions of IL15 and its receptors in the brain. IL15 receptors show robust upregulation after neuroinflammation, suggesting a major role of IL15 signaling in cerebral function. Involvement of the IL15 system in neuropsychiatric behavior is reflected by the effects of IL15, IL15Rα, and IL2Rγ deletions on neurobehavior and neurotransmitters, the effects of IL15 treatment on neuronal activity, and the potential role of IL15 in neuroplasticity/neurogenesis. The results show that IL15 modulates GABA and serotonin transmission. This may underlie deficits in mood (depressive-like behavior and decreased normal anxiety) and memory, as well as activity level, sleep, and thermoregulation. Although IL15 has only a low level of permeation across the blood-brain barrier, peripheral IL15 is able to activate multiple signaling pathways in neurons widely distributed in CNS regions. The effects of IL15 in "preventing" neuropsychiatric symptoms in normal mice implicate a potential therapeutic role of this polypeptide cytokine.

The day when infection is confirmed is a better time point for mortality prediction in patients with severe acute pancreatitis

OBJECTIVES

The objective of the study was to compare the accuracy of predictive methods for mortality in patients with severe acute pancreatitis (SAP) on admission and on the day when infection was confirmed.

METHODS

Medical records of patients admitted for SAP in our hospital during January 2000 to November 2010 were retrospectively reviewed. Among those with infectious complications, time when infection was confirmed (TIC) and Acute Physiology and Chronic Health Evaluation II (APACHE II) score on admission and at the time when infection was confirmed (APACHE II OTIC) were studied. The correlations among the APACHE II score on admission, APACHE II OTIC score, and TIC were analyzed. The predictive accuracy was assessed by the area under the receiver operating characteristic curve.

RESULTS

Time when infection was confirmed correlated negatively with the APACHE II score on admission and the APACHE II OTIC score (P < 0.05). The optimum cutoff value and the corresponding areas under the receiver operating characteristic curve for APACHE II score on admission, APACHE II OTIC score, and TIC were greater than 8, greater than 5, 12 days or less, and 0.67 (95% confidence interval [CI], 0.54-0.77), 0.84 (95% CI, 0.73-0.91), and 0.73 (95% CI, 0.61-0.82), respectively. Compared with the APACHE II score on admission, the APACHE II OTIC score was more accurate in predicting mortality (P = 0.029).

CONCLUSIONS

The time when infection is confirmed is a better time point for the reassessment of the outcome in patients with SAP.

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.

The changing character of acute pancreatitis: epidemiology, etiology, and prognosis

Acute pancreatitis continues to be a diagnostic and therapeutic challenge for physicians and surgeons. It ranks third in the list of hospital discharges for gastro-intestinal diseases. In most patients the cause is either gallstones or alcoholism. The overall mortality is less than 5%, but severe acute pancreatitis leads to prolonged hospitalization and much higher mortality. There are important differences in disease susceptibility and case fatality rates: the incidence is higher in blacks than in whites, and mortality is higher in older patients than in younger patients. Reports from various countries reveal that the frequency of acute pancreatitis is increasing, perhaps in relation to rising obesity rates, which would increase the likelihood of gallstone pancreatitis. Conversely, mortality rates for acute pancreatitis are declining in many, but not all, reports.

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.