Acute phase response in acute pancreatitis: a comparison with abdominal sepsis

Cytokine clearance in serum and peritoneal fluid of patients undergoing damage control surgery with abdominal negative pressure therapy for abdominal sepsis

Objectives

Open abdomen technique with negative pressure therapy (NPT) is widely used in patients with severe abdominal sepsis. The aim of this study was to evaluate cytokine clearance in serum and peritoneal fluid during NPT.

Methods

This prospective pilot study included six patients with severe abdominal sepsis requiring discontinuity resection and NPT for 48 h followed by planned reoperation. Cytokines (IL6, IL8, IL10, TNFalpha, and IL1beta) were measured in the serum and peritoneal fluid during index operation, on postoperative days 0, 1, and 2.

Results

Concentrations of cytokines in peritoneal fluid were higher than in serum. IL10 showed a clearance both in serum (to 16.6%, p=0.019) and peritoneal fluid (to 40.9%, p=0.014). IL6 cleared only in serum (to 24.7%, p=0.001) with persistently high levels in peritoneal fluid. IL8 remained high in both serum and peritoneal fluid. TNFalpha and IL1beta were both low in serum with wide range of high peritoneal concentrations. Only TNFalpha in peritoneal fluid showed significant differences between patients with ischemia vs. perforation (p=0.006).

Conclusions

The present pilot study suggests that cytokines display distinct patterns of clearance or persistence in the peritoneal fluid and serum over the first 48 h of treatment in severe abdominal sepsis with NPT.

Efficacy and safety of active negative pressure peritoneal therapy for reducing the systemic inflammatory response after damage control laparotomy (the Intra-peritoneal Vacuum Trial): study protocol for a randomized controlled trial

Background

Damage control laparotomy, or abbreviated initial laparotomy followed by temporary abdominal closure (TAC), intensive care unit resuscitation, and planned re-laparotomy, is frequently used to manage intra-abdominal bleeding and contamination among critically ill or injured adults. Animal data suggest that TAC techniques that employ negative pressure to the peritoneal cavity may reduce the systemic inflammatory response and associated organ injury. The primary objective of this study is to determine if use of a TAC dressing that affords active negative pressure peritoneal therapy, the ABThera Open Abdomen Negative Pressure Therapy System, reduces the extent of the systemic inflammatory response after damage control laparotomy for intra-abdominal sepsis or injury as compared to a commonly used TAC method that provides potentially less efficient peritoneal negative pressure, the Barker’s vacuum pack.

Methods/Design

The Intra-peritoneal Vacuum Trial will be a single-center, randomized controlled trial. Adults will be intraoperatively allocated to TAC with either the ABThera or Barker’s vacuum pack after the decision has been made by the attending surgeon to perform a damage control laparotomy. The study will use variable block size randomization. On study days 1, 2, 3, 7, and 28, blood will be collected. Whenever possible, peritoneal fluid will also be collected at these time points from the patient’s abdomen or TAC device. Luminex technology will be used to quantify the concentrations of 65 mediators relevant to the inflammatory response in peritoneal fluid and plasma. The primary endpoint is the difference in the plasma concentration of the pro-inflammatory cytokine IL-6 at 24 and 48 h after TAC dressing application. Secondary endpoints include the differential effects of these dressings on the systemic concentration of other pro-inflammatory cytokines, collective peritoneal and systemic inflammatory mediator profiles, postoperative fluid balance, intra-abdominal pressure, and several patient-important outcomes, including organ dysfunction measures and mortality.

Discussion

Results from this study will improve understanding of the effect of active negative pressure peritoneal therapy after damage control laparotomy on the inflammatory response. It will also gather necessary pilot information needed to inform design of a multicenter trial comparing clinical outcomes among patients randomized to TAC with the ABThera versus Barker’s vacuum pack.

Trial registration

ClinicalTrials.gov identifier http://www.clicaltrials.gov/ct2/show/NCT01355094

Monocytes in systematic inflammatory response syndrome: differences between sepsis and acute pancreatitis

AIM

To unravel the differences between systematic inflammatory response syndrome (SIRS) of acute pancreatitis compared to the same syndrome in sepsis.

METHODS

Twenty-five patients were enrolled, 12 with sepsis and 13 acute pancreatitis. After diagnosis 20 mL blood was sampled. Half were assayed for isolation of monocytes and 10 mL was centrifuged for serum test of tumor necrosis factor alpha (TNFalpha and interleukin-6 (IL-6). Half of monocytes were incubated in the presence of patients' serum and supernatants were collected. The other half was treated for estimation of optical photometry under caspase-3 inhibition. TNFalpha and IL-6 were estimated by an enzyme immunoassay.

RESULTS

median+/-SE of serum IL-6 in septic patients and acute pancreatitis patients was 192.30+/-35.40 ng/L and 21.00+/-16.05 ng/L, respectively (P<0.01). Respective values of caspase-3 were 0.94+/-0.17 pmol/min 10(4) cells and 0.34+/-0.09 pmol/min 10(4) cells (P<0.05). IL-6 of monocyte supernatants of patients with sepsis was significantly increased after addition of patients' serum, while that of patients with acute pancreatitis did not show significant difference.

CONCLUSION

The data have shown that monocyte activity is different between acute pancreatitis and sepsis. This phenomenon might be explained as a different pathway to the pro-inflammatory cytokines release or could be a novel anti-inflammatory response in acute pancreatitis.

Bile-pancreatic juice exclusion promotes Akt/NF-kappaB activation and chemokine production in ligation-induced acute pancreatitis

Using a unique surgical model (the donor rat model), we showed previously that duodenal replacement of bile-pancreatic juice, obtained fresh from a donor rat, ameliorates ligation-induced acute pancreatitis. We hypothesize that bile-pancreatic juice exclusion from gut exacerbates Akt/nuclear factor-kappaB (NF-kappaB) pathway activation and induces chemokine production in ligation-induced acute pancreatitis. We compared rats with bile-pancreatic duct ligation to those with duodenal bile-pancreatic juice replacement fresh from a donor rat beginning immediately before duct ligation. Sham control rats had ducts dissected but not ligated. Rats were killed 1 or 3 hours after operation (n = 7/group). Akt activation (immunoblotting, immune-complex kinase assay, and ELISA), inhibitory protein I-kappaB (IkappaB) activation (immunoblotting), and production of chemokines MCP-1 and RANTES (ELISA) were measured in pancreatic homogenates. NF-kappaB was quantitated in nuclear fractions using electrophoretic mobility shift assay. Duct ligation produced significant increases in pancreatic Akt, IkappaB, and NF-kappaB activation and production of MCP-1 and RANTES. Activation of the Akt/NF-kappaB pathway and increased MCP-1 and RANTES production in response to duct ligation were significantly reduced by bile-pancreatic juice replacement (ANOVA, P < 0.05). Bile-pancreatic juice exclusion stimulates Akt/NF-kappaB pathway activation and increases chemokine production in ligation-induced acute pancreatitis.

Immune status and inflammatory response differ locally and systemically in severe acute pancreatitis

OBJECTIVE

Acute pancreatitis (AP) is an inflammatory disorder that develops a complex cascade of immunological events. The local and systemic immune status and inflammatory response might contribute to the understanding of underlying pathophysiological mechanisms and potential treatment.

MATERIAL AND METHODS

Severe AP was induced by intraductal perfusion of 5% sodium taurodeoxycholate in rats. mRNA expression of cytokines and chemokines was determined by reverse transcriptase-polymerase chain reaction (RT-PCR) and NF-kappaB activation was assessed by electrophoretic mobility shift assay in fresh pancreatic acini and circulating monocytes 1, 3, 6 or 9 h after sham operation, induction of AP or N-acetylcysteine (NAC) pretreatment. Flow cytometry was performed on cells obtained from the peripheral blood.

RESULTS

An inverse relationship in pancreatic and circulating monocytic NF-kappaB activation was detected 6 and 9 h after induction of AP. NAC further suppressed monocytic NF-kappaB activation induced by AP as seen 9 h after induction of AP. A marked constitutive increase in the expression of IL-6, CINC and MCP-1 was seen in pancreatic acini, whereas no change in mRNA expression of inflammatory mediators was observed in circulating monocytes 6 h after induction of AP. Flow cytometry further confirmed the altered function of circulating monocytes.

CONCLUSIONS

The different immune status and inflammatory response in the pancreas and circulating monocytes improve the understanding of the mechanisms by which systemic inflammatory response syndrome (SIRS) and multiple organ dysfunction syndrome (MODS) develop in severe AP. A potential therapeutic approach could be to restore the functional capacity of the immune system in AP. The use of an NF-kappaB inhibitor, preferentially reaching the local inflammatory foci, could be a potential future way of intervention.

Sophorolipids block lethal effects of septic shock in rats in a cecal ligation and puncture model of experimental sepsis*

OBJECTIVE

Sophorolipids, a family of natural and easily chemoenzymatically modified microbial glycolipids, are promising modulators of the immune response. The potential of the therapeutic effect of sophorolipids was investigated in vivo in a rat model of sepsis and in vitro by analysis of nitric oxide and cytokine production.

DESIGN

Prospective, randomized animal study.

SETTING

Experimental laboratory.

SUBJECTS

Male Sprague-Dawley rats, 200-240 g.

INTERVENTIONS

Intra-abdominal sepsis was induced in vivo in 166 rats via cecal ligation and puncture (CLP); 60 rats were used to characterize the model. The remaining rats were treated with sophorolipids or vehicle (dimethylsulfoxide [DMSO]/physiologic saline) by intravenous (iv) tail vein or intraperitoneal (IP) injection immediately post-CLP (25/group). Survival rates were compared at 36 hrs after surgery. In vitro, macrophages were cultured in lipopolysaccharide (LPS) +/- sophorolipid and assayed for nitric oxide (NO) production and gene expression profiles of inflammatory cytokines. In addition, splenic lymphocytes isolated from CLP rats +/- sophorolipid treatment (three per group) were analyzed for cytokine production by RNase protection assay.

MEASUREMENTS AND MAIN RESULTS

CLP with 16-gauge needles optimized sepsis induction and resultant mortality. Sophorolipid treatment improved rat survival by 34% (iv) and 14% (IP) in comparison with vehicle controls (p < .05 for iv treatment). Sophorolipids decreased LPS-induced macrophage NO production by 28% (p < .05). mRNA expression of interleukin (IL)-1beta was downregulated by 42.5 +/- 4.7% (p < .05) and transforming growth factor (TGF)-beta1 was upregulated by 11.7 +/- 1.5% (p < .05) in splenocytes obtained 6 hrs postsophorolipid treatment. LPS-treated macrophages cultured 36 hrs with sophorolipids showed increases in mRNA expression of IL-1alpha (51.7%), IL-1beta (31.3%), and IL-6 (66.8%) (p < .05).

CONCLUSIONS

Administration of sophorolipids after induction of intra-abdominal sepsis significantly decreases mortality in this model. This may be mediated in part by decreased macrophage NO production and modulation of inflammatory responses.

Tumor necrosis factor α antibody prevents brain damage of rats with acute necrotizing pancreatitis

AIM: To study the protective effects of tumor necrosis factor α (TNFα ) antibody on pancreatic encephalopathy in rats.

METHODS: One hundred and twenty SD rats were randomly divided into normal control group, acute necrotizing pancreatitis group and TNFα antibody treated group. Acute hemorrhage necrotizing pancreatitis model in rats was induced by retrograde injection of 50 g/L sodium taurocholate into the pancreatobiliary duct. Serum TNFα was detected and animals were killed 12 h after drug administration. Changes in content of brain water, MDA and SOD as well as leucocyte adhesion of brain microvessels were measured.

RESULTS: In TNFα antibody treated group, serum TNFα level was decreased. Content of brain water, MDA and SOD as well as leucocyte adhesion were decreased significantly in comparison with those of acute necrotizing pancreatitis group (P < 0.05).

CONCLUSION: TNFα antibody can alleviate the brain damage of rats with acute hemorrhage necrotizing pancreatitis.