Intra-abdominal sepsis: the role of surgery

Heat stress enhances recovery of hepatocyte bile acid and organic anion transporters in endotoxemic rats by multiple mechanisms

Heat stress (HS) reduces the many sequelae of lipopolysaccharide (LPS)-induced endotoxemia. Without HS, endotoxins have been shown to induce a transcriptional down-regulation of hepatocyte transport proteins for bile acids and organic anions. We performed experiments in isolated perfused rat livers at various times after LPS administration with and without HS pretreatment to determine whether HS would correct deficient transport of bromosulfophthalein (BSP). Possible mechanisms involved were investigated in livers from intact animals. In isolated perfused livers, LPS injection reduced BSP excretion to 48% compared with saline-injected controls (P < 0.01). When HS was applied 2 hours prior to LPS, BSP excretion increased to 74% of controls (P < 0.05 vs LPS and controls). Expression of the basolateral (Oatp1a1) and canalicular (Mrp2) organic anion transporter involved in the transport of BSP recovered more rapidly when HS preceded LPS application. Recovery of mRNA levels of these transporters occurred also earlier. Coimmunoprecipitation experiments and immunoelectron microscopy using a double immunogold labeling of heat shock protein 70 (HSP70) and various hepatocyte transporters suggested colocalization with HSP70 for the canalicular bile acid transporter (Bsep) in the subcanalicular space. In contrast, no colocalization was shown for Ntcp and anion transporters. In conclusion, we could show that HS enhances recovery of organic anion transporters and bile acid transporters following endotoxemia. Faster recovery of mRNA seems to be a key mechanism for anion transporters, whereas physical interaction with HSP70 plays a role in preservation of bile acid transporters. This interaction of HSP70 and canalicular transporters occurs only in pericanalicular vesicles but not when the protein is integrated into the plasma membrane.

Meta-analysis of relaparotomy for secondary peritonitis

BACKGROUND

Planned relaparotomy and relaparotomy on demand are two frequently employed surgical treatment strategies for patients with abdominal sepsis.

METHODS

The available literature was evaluated to compare the efficacy of both surgical treatment strategies. A systematic search for studies comparing planned and on-demand relaparotomy strategies in adult patients with secondary peritonitis was employed. Studies were reviewed independently for design features, inclusion and exclusion criteria, and outcomes. The primary outcome measure was in-hospital mortality.

RESULTS

No randomized studies were found; eight observational studies with a total of 1266 patients (planned relaparotomy, 286; relaparotomy on demand, 980) met the inclusion criteria and were included in the meta-analysis. These eight studies were heterogeneous on clinical and statistical grounds (chi2= 40.7, d.f. = 7, P < 0.001). Using a random-effects approach, the combined odds ratio for in-hospital mortality was 0.70 (95 per cent confidence interval 0.27 to 1.80) in favour of the on-demand strategy.

CONCLUSION

The combined results of observational studies show a statistically non-significant reduction in mortality for the on-demand relaparotomy strategy compared with the planned relaparotomy strategy when corrected for heterogeneity in a random-effects model. Owing to the non-randomized nature of the studies, the limited number of patients per study, and the heterogeneity between studies, the overall evidence generated by the eight studies was inconclusive.

Factors predisposing to bacterial invasion and infection

BACKGROUND

Bacterial infections remain important causes of morbidity and mortality in surgical patients. Our understanding of the effects of bacteria on the host, and also the defense mechanisms available to the host, is improving all the time. Modern tools in biochemistry, immunology, and molecular biology have provided powerful methods to further our understanding of the complex interactions that contribute to our host defense response. This review reflects current thinking regarding the factors that contribute to bacterial infection and host defense response.

DATA SOURCES

This review was compiled after an extensive review of the current and historical literature, and highlights a number of areas involved in the pathogenesis of bacterial infection.

CONCLUSIONS

Bacteria can have a wide-ranging and deleterious effect on the host. Many different therapeutic approaches have been attempted to modulate the host response and limit the deleterious effects of bacteria. As our understanding of the underlying processes improves, these therapies should improve accordingly.

Pancreatic and hepatic abscesses: a late complication in 10 patients with chronic pancreatitis

In this prospective long-term study of chronic pancreatitis (n = 336) over the last 3 decades, 10 patients with advanced calcific pancreatitis developed a sepsis associated with intra-abdominal abscesses (6 pancreatic, 4 hepatic). None of the known precipitating factors were present (e.g., no pancreatic necrosis or recent surgical/endoscopic interventions, no evidence of cholangitis). Nine of 10 patients had alcoholic chronic pancreatitis. Interestingly a pancreatojejunostomy in 9 of 10 patients had been performed up to 12 years previously. Cultures from abscess aspirates and/or blood were polymicrobial, mainly a mixed enteric flora in 8 patients. All patients recovered after an appropriate antibiotic therapy with or without drainage procedures. The pathogenesis of "spontaneous" abscess formation in advanced chronic pancreatitis and its relationship to pancreatojejunostomy remain to be established.