Renal failure complicating obstructive jaundice

Impact of biliary drainage prior to pancreatectomy

BACKGROUND

There is still a lack of clarity about the benefits of preoperative biliary drainage (PBD), which was introduced to improve the perioperative outcome in patients with obstructive jaundice caused by a periampullary tumour. The aim of this study was to determine whether operative and postoperative complications increase in patients undergoing PBD during pancreatoduodenectomy (PD).

MATERIAL AND METHODS

Retrospective examination was made of patients who underwent PBD for a periampullary tumour in our hospital between 2006 and 2014. From these, the patients were identified who had PBD with endoscopic retrograde cholangiopancreatography and these patients were further separated into two groups, as one group of patients with plastic stents and the other group of patients with metallic stents. Patients with pancreas head cancer were also separated into two groups as those who were and were not applied with PBD. The preoperative, intraoperative and postoperative characteristics of the patients were evaluated.

RESULTS

A total of 123 patients were retrospectively reviewed. Biliary stent placement with PBD was applied to 48 patients, of whom 31 had metallic stents and 17 had plastic stents. In general, there was no difference between the PBD and the non-PBD groups in respect of the preoperative, operative and postoperative results. When patients with tumour of the pancreas head only were examined, the rate of wound infection was higher in the PBD group and there was no difference in the other parameters. Moreover, there was no difference between the patients with metallic stents and those with plastic stents in respect of outcomes.

CONCLUSIONS

With the exception of wound site infection, although no difference was observed between the PBD and the non-PBD groups based on intraoperative and postoperative complications, because of the distinctive inherent complications of PBD it is essential to manage such patients properly and to carefully select the patients for the PBD procedure.

Preoperative Biliary Drainage Does Not Independently Reduce Survival After Pancreaticoduodenectomy Among Patients With Pancreatic Ductal Adenocarcinoma: A National Registry Study

Objective

This study aimed to explore a possible relationship between preoperative biliary drainage (PBD) and overall survival in a national cohort of Swedish patients who underwent pancreaticoduodenectomy (PD) for pancreatic ductal adenocarcinoma (PDAC).

Background

PBD has been shown to increase postoperative complications after PD, but its use is steadily increasing. There are a few small studies that have indicated that PBD might in itself negatively affect overall survival after PD.

Methods

Patients from the Swedish National Registry for tumors in the pancreatic and periampullary region diagnosed from 2010 to 2019 who underwent PD for PDAC were included. Kaplan-Meier curves, log-rank tests and Cox proportional hazards analyses were performed to investigate survival.

Results

Out of 15,818 patients in the registry, 3113 had undergone PD, of whom 1471 had a histopathological diagnosis of PDAC. Patients who had undergone PBD had significantly worse survival, but the effect of PBD disappeared in the multivariable analysis when elevated bilirubin at any time was included.

Conclusions

PBD does not independently influence survival after PD for PDAC, but this study implies that even a nominally increased preoperative bilirubin level might impair long-term survival.

[Relief of Obstruction in the Management of Pancreatic Cancer]

Pancreatic cancer is a major cause of cancer-related mortality and morbidity, and its incidence is increasing as the population is aging. On the other hand, significant improvement in the prognosis has not occurred. The absence of early diagnosis means that many patients are diagnosed only when they develop symptoms, such as jaundice, due to a biliary obstruction. The role of endoscopy in multidisciplinary care for patients with pancreatic cancer continues to evolve. Controversy remains regarding the best preoperative biliary drainage in patients with surgically resectable pancreatic head cancer. In general, patients undergoing a surgical resection usually do not require preoperative biliary drainage unless they have cholangitis or receive neoadjuvant chemotherapy. If biliary drainage is performed prior to surgery, the patient's condition and a multidisciplinary approach should be considered. With the increasing life expectancy of patients with pancreatic cancer, the need for more long-time biliary drainage or pre-operative biliary drainage is also increasing. Strong evidence of endoscopic retrograde cholangiopancreatography (ERCP) as a first-line and essential treatment for biliary decompression has been provided. On the other hand, the use of endoscopic ultrasound-guided biliary drainage as well as percutaneous biliary drainage has been also recommended. During ERCP, self-expandable metal stent could be recommended instead of a plastic stent for the purpose of long stent patency and minimizing stent-induced complications. In this review, several points of view regarding the relief of obstruction in patients with pancreatic cancer, and optimal techniques are being discussed.

Spironolactone rescues renal dysfunction in obstructive jaundice rats by upregulating ACE2 expression

Postoperative acute renal failure in patients with obstructive jaundice is still a serious clinically complication, yet the mechanisms remain unclear. Renin-angiotensin-aldosterone system (RAAS) plays a central role in renal disease progression. Several lines of evidence shows that angiotensin-converting-enzyme-2 (ACE2), a main effector of RAAS acts as a local regulator for renal protection. This study aims to investigate the role of ACE2 and the effect of spironolactone treatment in obstructive jaundice(OJ) rats with renal injury. The rats with obstructive jaundice were established by bile duct ligation. Total bilirubin (TBil), serum creatinine (Scr) and the expression of ACE2 in kidney tissue of obstructive jaundice rats were detected. Comparatively, the expression of ACE2, renin, angiotensin II (AngII), angiotensin-(1-7)[Ang-(1-7)], aldosterone and intercellular adhesion molecule 1 (ICAM-1) in kidney tissues after spironolactone administration were measured by ELISA. Renal necrosis, inflammation and fibrosis induced by OJ were also measured by HE staining and Masson staining. The correlation between the expression of ACE2 and TBil, also the Scr level were investigated. With the time of common bile duct ligation prolonged, the TBil and Scr concentration increased while the expression of ACE2 in OJ rats' kidney tissues decreased. However, after spironolactone intervention, the expressions of ACE2, renin, AngII, Ang-(1-7), aldosterone and ICAM-1 in kidney tissue were changed, moreover, necrotic, inflammatory and fibrotic condition was also decreased. The relationship between the mRNA expression of ACE2 and TBil/Scr was observed to be moderately negatively correlated (r = -0.516, R² = 0.292, P < 0.01), (r = -0.576, R² = 0.332, P < 0.01), respectively. RAAS exerted an important effect in the renal damage caused by OJ. Spironolactone intervention not only improved the degree of renal fibrosis induced by OJ, but also upregulated the ACE2 expression in the kidney of OJ rats and rescued the renal function.

Preoperative biliary drainage in resectable pancreatic cancer: a systematic review and network meta-analysis

BACKGROUND

Controversy remains about the best pre-operative management of jaundice in patients with resectable pancreatic head cancer (RPC) undergoing planned pancreaticoduodenectomy (PD).

OBJECTIVE

The aim of this study was to compare rates of post-operative complications in patients undergoing four pre-operative approaches (POA): preoperative biliary drainage with plastic stent (PBD-PS), metal stent (PBD-MS), and percutaneous transhepatic drain (PBD-PT), or no pre-operative biliary drainage (NPBD).

METHOD

A study was included in the systematic review if it assessed the effects of PBD on post-operative outcomes in jaundiced patients with RPC. Endpoints were the rate of any post-operative complication, wound infection, intra-abdominal infection and post-operative bleeding. A network meta-analysis (NMA) was performed to rank the POAs from the best to worst, for each outcome.

RESULTS

Thirty-two studies were included in the systematic review. Ten out of 32 studies included in the systematic review reported at least one of the 4 outcomes of interest and thus were used for NMA. The calculated odds ratios and P-scores ranked NPBD as the best approach. There was insufficient evidence to determine the best modality of PBD among PBD-PS, PBD-MS and PBD-PT.

CONCLUSIONS

No preoperative biliary drainage may be the best management of preoperative jaundice in patients with RPC before PD. Further studies are needed to determine the best modality in patients that need PBD.

Does Hyperbilirubinemia Contribute to Adverse Patient Outcomes Following Pancreatoduodenectomy?

BACKGROUND

Jaundice due to biliary obstruction leads to multiple physiologic derangements and a decline in performance status that may result in unfavorable intra- and postoperative outcomes following a Whipple procedure. While preoperative biliary decompression may improve synthetic function, this strategy has been reported to increase the incidence of infectious complications following surgery. We hypothesized that hyperbilirubinemia at the time of pancreatoduodenectomy (PD) would be a risk factor for increased morbidity and mortality postoperatively.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) Pancreatectomy Demonstration Project and the 2014 Procedure Targeted Pancreatectomy databases were queried for patients with a bilirubin level obtained within 7 days of PD. Results were compared among patients with bilirubin level percentiles <80th (0-2.9 mg/dL), 80-90th (3-7.3 mg/dL), and >90th (>7.3 mg/dL). Data were further evaluated between those with a bilirubin ≥10 mg/dL and those with a normal level and by utilizing bilirubin as a continuous variable. Outcomes included 30-day mortality and overall and serious morbidity as previously defined by ACS-NSQIP. Categorical variables were compared using chi-squared, Fisher's exact, Kruskal-Wallis, or Wilcoxon rank sum tests with a p = 0.05 considered significant.

RESULTS

The combined databases yielded 2556 patients who had PD and a preoperative bilirubin level for analysis. When comparing patients with bilirubin levels at the 80th (n = 2055), 80-90th (n = 273), and >90th percentiles (n = 228), no difference was observed among groups with respect to overall and serious morbidity or mortality. Similarly, no difference in postoperative outcomes was observed between the 147 patients who had a bilirubin ≥10 mg/dL and those with normal levels or when bilirubin increased when levels were analyzed as a continuous variable.

CONCLUSION

Modest degrees of hyperbilirubinemia were not shown to affect morbidity and mortality following pancreatoduodenectomy. The indication and need for preoperative biliary decompression should be reserved, and utilized selectively, only for those with symptomatic, elevated bilirubin levels.

Protective effects of Radix Astragali injection on multiple organs of rats with obstructive jaundice

OBJECTIVE

To investigate the protective effects and mechanisms of Radix Astragali Injection on multiple organs of rats with obstructive jaundice (OJ).

METHODS

A total of 180 rats were randomly divided into the sham-operated, model control and treated groups (60 in each group). On 7, 14, 21 and 28 days after operation, the serum contents of alanine aminotransferase (ALT), aspartate aminotransferase (AST), r-glutamyl transpeptidase (r-GT), total bilirubin (TBil), direct bilirubin (DBil), blood urine nitrogen (BUN), and creatinine (CREA) were determined. And the pathological changes of livers, kidneys and lungs, and protein expressions of toll-like receptor-4 (TLR-4) of livers, intercellular adhesion molecule-1 (ICAM-1) of lungs, Bax and nuclear factor-kappa B (NF-κB), as well as apoptotic indexes of multiple organs were observed, respectively.

RESULTS

The pathological severity scores of multiple organs (including livers on 7, 14, 21 and 28 days, kidneys on 14 and 28 days, and lungs on 14 days), serum contents of ALT (14 and 21 days), AST (14 days), TBil (7, 14, 21 and 28 days), DBil (14 and 21 days), BUN (28 days), protein expressions of TLR-4 (in livers, 28 days), Bax (in livers and kidneys, 21 days), and apoptotic indexes in livers (7 and 21 days) in the treated group were significantly lower than those in the model control group (P<0.05 or P<0.01).

CONCLUSION

Radix Astragali Injection exerts protective effects on multiple organs of OJ rats by improving the pathological changes of lung, liver and kidney, decreasing the serum index of hepatic and renal function as well as inhibiting the protein expression of TLR-4 and Bax in the livers and Bax in the kidneys.

Should preoperative biliary drainage be routinely performed for obstructive jaundice with resectable tumor?

Obstructive jaundice is a common clinical manifestation of malignant lesions adjacent to extrahepatic bile duct, ampulla or pancreatic head. Animal experiments and some clinical observations have demonstrated that preoperative biliary drainage could improve liver function as well as reduce endotoxemia, thereby reducing the incidence of perioperative complications. However, a number of randomized, controlled studies have found that preoperative biliary drainage failed to improve prognosis or reduce the incidence of perioperative complications; in contrast, it might increase the incidence of complications and cause extra financial burden on patients. Thus, whether preoperative biliary drainage should be performed or not is controversial. Since clinical randomized controlled studies are more relevant in clinical setting, we believe that preoperative biliary drainage should not be routinely performed for obstructive jaundice with resectable tumors. More randomized, controlled, prospective studies should be conducted for further exploration.

Obstructive jaundice and perioperative management

The causes of obstructive jaundice are varied, but it is most commonly due to choledocholithiasis; benign strictures of the biliary tract; pancreaticobiliary malignancies; and metastatic disease. Surgery in patients with obstructive jaundice is generally considered to be associated with a higher incidence of complications and mortality. Therefore, it poses a considerable challenge to the anesthesiologist, surgeons, and the intensive care team. However, appropriate preoperative evaluation and optimization can greatly contribute to a favorable outcome for perioperative jaundiced patients. This article outlines the association between obstructive jaundice and perioperative management, and reviews the clinical and experimental studies that have contributed to our knowledge of the underlying pathophysiologic mechanisms. Pathophysiology caused by obstructive jaundice involving coagulopathies, infection, renal dysfunction, and other adverse events should be fully assessed and reversed preoperatively. The depressed cardiovascular effects of obstructive jaundice are worth noticing because it has complicated mechanisms and needs to be further explored. Alterations of anesthesia-related drugs induced by obstructive jaundice are varied and clinicians should be aware of the possible need for a decrease in the anesthetic dose. Recommendations concerning the perioperative management of the patients with obstructive jaundice including preoperative biliary drainage, anti-infection, nutrition support, coagulation reversal, cardiovascular evaluation, perioperative fluid therapy, and hemodynamic optimization should be taken.

Surgery in patients with portal hypertension: a preoperative checklist and strategies for attenuating risk

Patients with liver disease and portal hypertension are at increased risk of complications from surgery. Recent advances have allowed better optimization of patients with cirrhosis before surgery and a reduction in postoperative complications. Despite this progress, the estimation of surgical risk in a patient with cirrhosis is challenging. The MELD score has shown promise in predicting postoperative mortality compared with the Child-Turcotte-Pugh score. This article addresses current concepts in the perioperative evaluation of patients with liver disease and portal tension, including a preoperative liver assessment (POLA) checklist that may be useful towards mitigating perioperative complications.

Protective effects of intravenous anesthetics on kidney tissue in obstructive jaundice

AIM: To evaluate the protective effects on kidney tissue of frequently used intravenous anesthetics (ketamine, propofol, thiopental, and fentanyl) in rats with obstructive jaundice.

METHODS: There is an increased incidence of postoperative acute renal failure in patients with obstructive jaundice. Thirty-two Wistar-albino rats were randomly divided into four equal groups. Laparatomy was performed on each animal in the four groups and common bile ducts were ligated and severed on day 0. After 7 d, laparotomy was again performed using ketamine, propofol, thiopental, or fentanyl anesthesia whose antioxidative properties are well known in oxidative stress in a rat liver model of obstructive jaundice. After 2 h, the rats were sacrificed. Renal tissue specimens were analyzed for catalase, superoxide dismutase and malondialdehyde enzymes activities. All values are expressed as the mean ± SD. P values less than 0.05 were considered statistically significant.

RESULTS: All animals survived without complications until the end of the study. Enlargement in the bile duct and obstructive jaundice were observed in all rats. Catalase was found to be significantly lower in the fentanyl group than in the ketamine (P = 0.039), propofol (P = 0.012), and thiopental (P = 0.001) groups. Superoxide dismutase activities were similar in all groups (P > 0.05). Malondialdehyde was found to be significantly lower in the ketamine group than in the propofol (P = 0.028), thiopental (P = 0.002) and fentanyl (P = 0.005) groups. Malondialdehyde was also lower in the fentanyl group than in the thiopental group (P = 0.001). The results showed that obstructive jaundice sensitizes renal tissue to damage under the different anesthetics.

CONCLUSION: Among the agents tested, ketamine and propofol generated the least amount of oxidative stres on renal tissues in this rat model of obstructive jaundice created by common bile duct ligation. The importance of free radical injury in renal tissue in obstructive jaundice under different intravenous anesthetics during hepatobiliary and liver transplant surgery should be considered for prevention of postoperative acute renal failure.

The optimal duration of preoperative biliary drainage for periampullary tumors that cause severe obstructive jaundice

BACKGROUND

Despite routine preoperative biliary drainage (PBD) with periampullary cancer, its optimal duration has not been established. The objective of this study was to investigate PBD in severely jaundiced patients.

METHODS

A total of 120 patients with periampullary tumors who underwent surgery with intent to cure after PBD for severe obstructive jaundice were enrolled. According to the duration of PBD, 66 and 54 patients were classified into the long-term (≥2 weeks) and short-term (<2 weeks) groups.

RESULTS

PBD-related complications occurred in 6 (9.1%) and 14 (25.9%) patients in the short-term and long-term groups, respectively (P = .014). Rates of surgery-related complications and mortalities were not significantly different between the 2 groups. The R0 resection rate tended to be lower (P = .054) and the mean length of hospital stay was significantly longer (P = .039) in the long-term group.

CONCLUSIONS

PBD duration <2 weeks is more appropriate in severely jaundiced patients with periampullary cancer.

In vivo and ex vivo effects of propofol on myocardial performance in rats with obstructive jaundice

BACKGROUND

Responsiveness of the "jaundiced heart" to propofol is not completely understood. The purpose of this study was to evaluate the effect of propofol on myocardial performance in rats with obstructive jaundice.

METHODS

Male Sprague-Dawley rats (n = 40) were randomly allocated into two groups, twenty underwent bile duct ligation (BDL), and 20 underwent a sham operation. Seven days after the surgery, propofol was administered in vivo and ex vivo (Langendorff preparations). Heart rate, left ventricular end-systolic pressure (LVESP) left ventricular end-diastolic pressure (LVEDP), and maximal rate for left ventricular pressure rise and decline (± dP/dtmax ) were measured to determine the influence of propofol on the cardiac function of rats.

RESULTS

Impaired basal cardiac function was observed in the isolated BDL hearts, whereas in vivo indices of basal cardiac function (LVESP and ± dP/dt) in vivo were significantly higher in rats that underwent BDL compared with controls. With low or intermediate concentrations of propofol, these indices of cardiac function were within the normal physiologic range in both groups, and responsiveness to propofol was unaffected by BDL. When the highest concentration of propofol was administrated, a significant decline in cardiac function was observed in the BDL group.

CONCLUSIONS

In rats that underwent BDL, basal cardiac performance was better in vivo and worse ex vivo compared with controls. Low and intermediate concentrations of propofol did not appear to impair cardiac function in rats with obstructive jaundice.

The effect of calcitonin gene-related peptide on healing of intestinal anastomosis in rats with experimental obstructive jaundice

PURPOSE

Intestinal anastomotic healing is a complex procedure in which several mediators and cytokines play roles. Calcitonin gene-related peptide is an important neuropeptide in inflammation. In this study we aimed to investigate the effect of calcitonin gene-related peptide on healing of intestinal anastomosis in rats with obstructive jaundice.

MATERIALS AND METHODS

Obstructive jaundice was induced in rats by the ligation and division of the common bile duct. Four days after the operation, intestinal anastomosis was performed, and either calcitonin gene-related peptide or 0.9% NaCl was administered intraperitoneally to these jaundiced rats and controls. The concentrations of serum tumor necrosis factor-alpha (TNF-alpha) and triglyceride levels of all rats were measured, and healing of the anastomosis was evaluated by measuring the bursting pressure and hydroxyproline content on the 7th postoperative day.

RESULTS

Calcitonin gene-related peptide was found to have positive effects on healing of the anastomosis by inhibiting the effects of TNF-alpha and increasing the bursting pressure and hydroxyproline content of the anastomosis.

CONCLUSION

Calcitonin gene-related peptide increases anastomotic wound healing in experimental anastomosis in the presence of obstructive jaundice in rats.

Preoperative biliary drainage in patients with obstructive jaundice: history and current status

RATIONALE

Preoperative biliary drainage (PBD) has been introduced to improve outcome after surgery in patients suffering from obstructive jaundice due to a potentially resectable proximal or distal bile duct/pancreatic head lesion. In experimental models, PBD is almost exclusively associated with beneficial results: improved liver function and nutritional status; reduction of systemic endotoxemia; cytokine release; and, as a result, an improved immune response. Mortality was significantly reduced in these animal models. Human studies show conflicting results.

FINDINGS

For distal obstruction, currently the "best-evidence" available clearly shows that routine PBD does not yield the appreciated improvement in postoperative morbidity and mortality in patients undergoing resection. Moreover, PBD harbors its own complications. However, most of the available data are outdated or suffer from methodological deficits.

CONCLUSION

The highest level of evidence for PBD to be performed in proximal obstruction, as well as over the preferred mode, is lacking but, nevertheless, assimilated in the treatment algorithm for many centers. Logistics and waiting lists, although sometimes inevitable, could be factors that might influence the decision to opt for PBD, as well as an extended diagnostic workup with laparoscopy (on indication) or scheduled preoperative chemotherapy.

Excessive inflammation but decreased immunological response renders liver susceptible to infection in bile duct ligated mice

BACKGROUND/AIMS

Obstructive jaundice (OJ) is associated with increased surgical morbidity and infectious complication. The aim of the current study was to clarify the mechanism of excessive inflammation and susceptibility to infection in OJ.

METHODS

C57/BL6 mice were subjected to bile duct ligation (BDL) or sham surgery. Expression tumor necrosis factor-alpha, macrophage inflammatory protein-2, monocyte chemoattractant protein-1, inducible protein-10, and interleukin (IL)-10, activation of nuclear factor kappa B, fluorescence activated cell sorter analysis, serum alanine aminotransferase levels, and histology were examined. Survival after lipopolysaccharide (LPS) administration or cecal ligation and puncture 3 or 14 d after surgery was determined. IL-1beta and interferon-gamma expression was examined after LPS administration.

RESULTS

OJ induced nuclear factor kappa B activation and increased expression of macrophage inflammatory protein-2, which caused significant increases in neutrophil recruitment. Serum alanine aminotransferase levels increased consistent with histological observations in OJ. Mononuclear cells were recruited in the liver after BDL associated with monocyte chemoattractant protein-1 up-regulation. The recruitment of NK and T cells was varied, consistent with IP-10 expression during the time course of OJ. IL-10 expression was significantly up-regulated 14 d after BDL. After LPS administration, the mice at 3 d after BDL and at 3 and 14 d after sham surgery were all still alive, but all mice at 14 d after BDL died. After LPS administration, IL-1beta significantly increased in the mice at 14 d after BDL.

CONCLUSIONS

Immune response such as expression of pro- and anti-inflammatory mediators and recruitment of immune cells may thus differ over the time course of OJ. Prolonged OJ may cause excessive inflammation, thus result in susceptibility to infection.

The use of High Performance Thin-Layer Chromatography to determine the role of membrane lipid composition in bile salt-induced kidney cell damage

INTRODUCTION

In obstructive liver disease bile salts are known to accumulate in and damage specific kidney cells. High Performance Thin-Layer Chromatography (HPTLC) was used to determine the membrane lipid composition of a range of kidney cells.

METHODS

Kidney cells were exposed to three hydrophobic bile salts (lithocholic, deoxycholic and chenodeoxycholic acids) and cytotoxicity was determined. In addition membrane lipids from the cells were extracted in a chloroform:methanol (2:1, v/v) solution and quantified by HPTLC.

RESULTS

The results reveal a differential toxicity to the bile acids with IC(50) values ranging from 79+/-5 microM to 394+/-13 microM. When the lipid composition of the most and least susceptible cells were assayed, the least susceptible cells had a much higher lipid composition (46.6+/-3.7 microg/mg protein compared to 28.1+/-5.2 microg/mg protein for the least susceptible cells).

DISCUSSION

These results suggest that HPTLC may be a useful technique when determining the mechanisms of toxicity of compounds which cause the disruption of the cell membrane.

The current standard of care in the periprocedural management of the patient with obstructive jaundice

This review provides a literature-based guide to the optimal management of the patient with obstructive jaundice with emphasis placed on prevention of complications.

The effect of caffeic acid phenethyl ester on bacterial translocation and intestinal damage in cholestatic rats

We investigated the effect of caffeic acid phenethyl ester in rat ileum injury induced by chronic biliary obstruction. Swiss albino rats were divided into three groups: Group 1, sham (n = 7); Group 2, common bile duct ligation (n = 7); and Group 3, common bile duct ligation plus caffeic acid phenethyl ester (n = 7). In the caffeic acid phenethyl ester-treated rats, ileum tissue levels of malondialdehyde and myeloperoxidase were significantly lower than those of the bile duct-ligated rats (P < 0.001). The levels of tumor necrosis factor-alpha, interleukin-6, and interleukin-1alpha in the caffeic acid phenethyl ester group were significantly lower than those in the bile duct ligation group (P < 0.03, P < 0.01, and P < 0.02 respectively). The present study demonstrates that intraperitoneal administration of caffeic acid phenethyl ester in bile duct-ligated rats reduces intestinal oxidative stress. This effect may be useful in the preservation of intestinal damage in cholestasis.

Effects of dexamethasone on small bowel and kidney oxidative stress and histological alterations in bile duct-ligated rats

Oxidative stress plays an important role in the pathogenesis of toxic liver diseases and other hepatic alterations including obstruction of bile flow. It has been shown that the gastrointestinal tract and renal tissue is particularly affected during obstruction of bile flow. In this study, we aimed to evaluate the effects of dexamethasone on small bowel and kidney oxidative stress and histological alterations in bile duct-ligated (BDL) rats. A total of 40 male Sprague-Dawley rats weighing 200-240 g were used in this study. Group 1 (Sham-control, n = 10) rats underwent laparotomy and bile duct was dissected from the surrounding tissue. Group 2 (Dexa-control, n = 10) rats underwent laparotomy and bile duct was dissected from the surrounding tissue. The rats received daily dexamethasone. Group 3 (BDL/Untreated, n = 10) rats were subjected to bile duct ligation and no drug was applied. Group 4 (BDL/Dexa, n = 10) rats received daily dexamethasone by orogastric tube for 14 days after BDL. At the end of the 2-week period, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), and malondialdehyde (MDA) were measured and biochemical and histological evaluation were processed. The mean serum bilirubin, liver enzymes, MDA level, and histopathological score significantly decreased and SOD, CAT, and GSH-Px values were significantly increased in group 4 when compared to group 3. Group 3 presented a significant increase in caecal count of E. coli and in aerobe/anaerobe ratio. In group 4, liver was moderately damaged. Ileal biopsies from group 4 demonstrated a significant increase in villus height, total mucosal thickness, and villus density when compared to group 3. Glomerular injury scores (GIS) and arterial injury scores (AIS) in group 3 rats were increased in the juxtamedullary region. In contrast to group 4, tubulo-interstitial lesions were diffuse in group 3 animals. Dexamethasone reduced small bowel and kidney oxidative stress and histological alterations in bile duct-ligated rats with increasing SOD, CAT, and GSH-Px and decreasing MDA levels in rats with obstructed bile duct.

Expression of rat renal cortical OAT1 and OAT3 in response to acute biliary obstruction

Renal function in the course of obstructive jaundice has been the subject of great interest; however, little is known about the expression of renal organic anion transporters. The objective of this work was to study, in rats with acute extrahepatic cholestasis, the cortical renal expression of the organic anion transporter 1 (OAT1) and the organic anion transporter 3 (OAT3), in association with the pharmacokinetics and renal excretion of furosemide (FS). Male Wistar rats underwent bile duct ligation (BDL rats). Pair-fed sham-operated rats served as controls. All studies were carried out 21 hours after surgery. Rats were anesthetized and the pharmacokinetic parameters of FS and the renal elimination of FS were determined. Afterwards, the kidneys were excised and processed for immunoblot (basolateral membrane and renal homogenates) or immunocytochemical (light microscopic and confocal immunofluorescence microscopic analysis) techniques. The systemic and renal clearance of FS as well as the excreted and secreted load of FS increased in BDL rats. In kidneys from BDL rats, immunoblotting showed a significant increase in the abundance of both OAT1 and OAT3 in homogenates from renal cortex. In basolateral membranes from kidney cortex of BDL rats, OATI abundance was also increased and OAT3 abundance was not modified. Immunocytochemical techniques confirmed these results. In conclusion, acute obstructive jaundice is associated with an upregulation of OAT1 and OAT3, which might explain, at least in part, the increased systemic and renal elimination of FS.

Endothelin activation and postoperative renal failure after human liver transplantation

Renal failure is an established risk factor for impaired patient outcome after orthotopic liver transplantation (OLT). As the endothelin pathway is known to be involved in the development of acute renal failure (ARF), we designed a study to clarify its role in ARF following OLT. Twenty consecutive patients with intact kidney function scheduled for their first OLT were prospectively studied. Plasma big endothelin-1 (ET-1) levels were measured before surgery, after graft reperfusion, and on the first and second postoperative day. According to postoperative glomerular filtration rate (GFR), patients were assigned to the acute renal dysfunction group (ARDF) and the non-ARDF group. Each patient's GFR was estimated according to the 4-variable formula used in the modification of diet in renal disease before surgery, daily within the first postoperative week, and at 1, 3, 12, and 24 months after surgery. Postoperative mean big ET-1 levels correlated significantly with the maximum percent decrease of GFR within 3 days after OLT (P < 0.01). The proportion of patients who developed ARDF was significantly correlated to mean postoperative big ET-1 quartiles (P < 0.01). In the ARDF group, the percent decrease of GFR within 24 months was significantly higher (P < 0.05) as compared to the non-ARDF group. In conclusion, patients who develop ARDF immediately after OLT do not fully recover to baseline regarding long-term kidney function. Short-term GFR was significantly correlated with postoperative big ET-1 plasma levels, suggesting renal dysfunction is mediated by the activated endothelin system.

Are bile acids involved in the renal dysfunction of obstructive jaundice? An experimental study in bile duct ligated rats

BACKGROUND

Surgery on patients with obstructive jaundice is associated with a significant risk of postoperative renal failure. Bile acids are implicated as nephrotoxins because they accumulate in the plasma and the kidney becomes their only excretory route in cholestasis. The experimental evidence favoring this proposal is inadequate and unconvincing. Therefore, we designed an animal experiment involving bile duct ligated (BDL) rats in which we could correlate variations in serum and urine bile acids with indices of nephrotoxicity and renal function.

HYPOTHESIS

Bile acids are putative nephrotoxins.

MATERIALS AND METHODS

Total serum and urine bile acid concentrations and profiles were determined using liquid chromatography/gas chromatography/mass spectrometry selected ion monitoring. Nephrotoxicity was assessed by renal histopathology and by determination of the urinary activities of the following enzymes: muramidase, glutamate dehydrogenase, alkaline phosphatase, N-acetyl-beta-D-glucosaminidase, and lactate dehydrogenase. Renal function was assessed by measuring urine osmolality, daily osmolar excretion, sodium excretion (U(Na)V), potassium excretion (U(K)V), and total protein and albumin excretion.

RESULTS

Maximum plasma concentrations and renal clearance of bile acids occurred between the third or fourth postoperative day following BDL. This peak coincided with maximal disruption of proximal convoluted tubule architecture and postoperative changes in renal function-increased urine flow rate and decreases in urine osmolality and sodium excretion. Thereafter, 1) plasma levels of bile acids returned toward normal levels, 2) urinary bile acid clearance declined, 3) normal renal histology was restored, and 4) normal renal function was reestablished. Throughout this period, fluctuations in enzymuria were evident. However, these shifts did not coincide with plasma and urine bile acid concentrations and histological and functional changes.

DISCUSSION AND CONCLUSIONS

Transient functional impairment of renal cation and water transport and nonspecific morphological changes in the proximal convoluted tubule occur 3 to 4 days following bile duct ligation in rats. These functional and morphological changes occurred when plasma total and urinary bile acids were at their peaks. Although it is tempting to equate association with causality, we cannot implicate bile acids as being responsible for the aberrations in renal function and structure following BDL. Accordingly, we have concluded that elevated plasma concentrations of bile acids are renal exacerbates acting in concert with other factors, be they prerenal or renal in origin to precipitate a cascade of events leading to postoperative renal failure in cholestasis.

Predictive value of risk factors in patients with obstructive jaundice

Clinical and laboratory parameters that may affect post-operative mortality and morbidity were studied in 215 patients operated on for obstructive jaundice. The cause of the bile duct obstruction was benign disease in 56.7% of patients and malignant disease in 43.3%. Overall postoperative mortality and morbidity rates were 21.9% and 33.5%, respectively. Eight risk factors were shown to be associated with increased mortality: age > 70 years; malignancy; leucocytosis > 15 000 cells/microl and fever > 38.5 degrees C; haematocrit < or = 30%; creatinine > 1.3 mg/dl; albumin < or = 3 g/dl; bilirubin > 20 mg/dl; and serum alkaline phosphatase > 100 IU/l. The simultaneous presence of less than three risk factors was always associated with post-operative survival, but concomitant existence of seven or more risk factors indicated 100% mortality. Understanding the factors related to post-operative morbidity and mortality in patients with obstructive jaundice will better guide appropriate surgical or non-surgical management and lead to improved survival.

Effects of ursodeoxycholic acid, glutamine and polyclonal immunoglobulins on bacterial translocation in common bile duct ligated rats

BACKGROUND

The present study was conducted to investigate the effects of ursodeoxycholic acid (UDCA), glutamine and i.v. polyclonal immunoglobulins (IVIG) on the bacterial translocation (BT) and intestinal integrity of obstructive jaundice (OJ) in an animal model.

METHODS

Fifty rats were randomized into five groups containing 10 rats each. All procedures were performed aseptically under general anaesthesia using intramuscular ketamine (25 mg/kg). The abdomen was opened and the common bile duct was identified, mobilized, doubly ligated using 5-0 silk and divided. In group 1 (the 'sham' group), the rats had a similar incision followed by mobilization of the common bile duct (CBD), without ligation or division. In group 2 rats, only common bile duct ligation (CBDL) was performed. In group 3, CBDL was performed and UDCA was administered by orogastric intubation once daily. In group 4 rats, CBDL was performed and glutamine was given by orogastric intubation once daily. Therapeutic substances were started orally on the day CBDL was fulfilled and were continued for 7 days. In group 5, IVIG was administrated via a femoral vein catheter just before CBDL. The animals were killed at the end of the 7th day, and serum levels of total bilirubin (TB), alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and gamma-glutamyl transpeptidase (GGT) were measured. Mesenteric lymph nodes (MLN), liver, spleen and blood were cultured. The terminal ileum specimens were examined histopathologically.

RESULTS

Bacterial translocation significantly increased in the MLN and spleen of rats in group 2 as compared to groups 3, 4 and 5 (P < 0.05, P = 0.001, P = 0.001, respectively). The BT of the liver in group 2 was significantly higher than that of group 5 (P < 0.05). In the blood, the BT was significantly higher in group 2 than groups 3, 4 and 5 (P < 0.05). The bacterial counts, colony-forming units per gram tissue (cfu/g), were found significantly higher in MLN, liver and spleen of rats in group 2 than those of groups 3, 4 and 5 (P = 0.000). The average villus height in the group 4 was significantly higher than that of groups 2, 3 and 5 (P = 0.000).

CONCLUSION

The present experimental study has demonstrated that the administration of glutamine, UDCA and IVIG reduce the incidence of BT and additionally glutamine preserves intestinal mucosal integrity.

Role of oxygen free radical scavengers in acute renal failure complicating obstructive jaundice

Obstructive jaundice is associated with high morbidity and mortality. Major complications such as pulmonary dysfunction, renal failure and sepsis are frequently encountered. Recent studies and observations suggest that the free oxygen radicals (FORs) produced in obstructive jaundice may play a significant role in the etiopathogenesis of acute renal failure (ARF). Thirty rats were divided into three groups, as sham, control and treatment groups containing 10 rats each. Laparatomy was performed on each animal in the control and treatment groups and common bile ducts were ligated. Common bile duct was observed but was not ligated for the rats in the sham group. Saline solution injection was begun on the first day of surgical procedure and repeated once a day during the following 5 days. The same procedure was performed with oxygen radical scavenger dimethyl sulfoxide (1.5 mg/kg/day i.p.) instead of saline in the treatment group. The rats were sacrificed on the 7th postoperative day. On the 7th postoperative day, the bilirubin, urea and creatinine levels of the control and treatment groups were significantly higher in comparison with the sham group (p < 0.01). Although there was no statistically significant difference between the bilirubin levels of the control and treatment groups (p > 0.05), the urea and creatinine levels in the treatment group were significantly lower (p < 0.01). On the 7th postoperative day, the erythrocyte superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) levels of the control and treatment groups were significantly lower than those of the sham group (p < 0.01), whereas renal and erythrocyte malondialdehyde (MDA) levels were significantly higher (p < 0.01). Although SOD and GSH-Px levels did not differ significantly between the treatment and control groups (p > 0.05), renal and erythrocyte MDA levels of the treatment group were significantly lower than those of the control group (p < 0.01). The histopathological scores were significantly higher in the control and treatment groups (p < 0.01); there was no significant difference between the control and treatment groups (p > 0.05). FORs seem to play a significant role in the etiopathogenesis of renal failure in obstructive jaundice. Antioxidant treatment may decrease oxidative damage due to FORs and may prevent renal failure.

Hepatorenal syndrome: diagnostic accuracy, clinical features, and outcome in a tertiary care center

OBJECTIVES

Hepatorenal syndrome (HRS) is a common and life-threatening entity that is associated with advanced liver disease. There are limited data on predisposing or precipitating factors related to the development of this syndrome. The aims of this study were: 1) to determine the accuracy of the diagnosis of HRS in an urban tertiary care center; 2) to compare features of HRS with those of non-HRS renal failure; and 3) to document the precipitating factors for HRS in this setting.

METHODS

We conducted a retrospective chart review of 46 patients at the Health Sciences Center in Winnipeg, Manitoba, who were diagnosed with HRS within the last 10 yr. In addition to assessing the accuracy of the diagnosis of HRS (as defined by the International Ascites Club), we also developed a database that included clinical and biochemical features of these patients' liver disease, possible predisposing factors, precipitating events, etiology of cirrhosis, and mortality rates. A cohort of 19 patients with advanced liver disease and renal failure not ascribed to HRS (non-HRS) served as controls.

RESULTS

A total of 46 patients were labeled as having HRS during their hospital stay, of whom 27 (59%) fulfilled International Ascites Club criteria. Their mean age was 51.8 +/- 12.1 yr, and 67% were male. Demographic and biochemical findings in the HRS patients were similar to those of the non-HRS patients. Hepatic encephalopathy (p < 0.03) and jaundice (p < 0.01) more commonly preceeded renal failure in the HRS group than in the controls. The most common predisposing factor for HRS was alcohol abuse. Precipitating factors for HRS included infection in 48% patients, GI bleeding in 33%, and over paracentesis in 27%. Drug-induced renal disease was significantly more common in patients with non-HRS renal failure. Contrary to previous reports, nonsteroidal anti-inflammatory drugs were not common precipitating factors of HRS. Alcohol-related liver disease was the most common underlying etiology of liver disease in all patients who developed renal failure but was proportionally higher in the HRS group. Mortality was almost universal in both groups, regardless of the cause of renal failure.

CONCLUSIONS

The diagnostic accuracy (or lack thereof) of HRS highlights the importance of ensuring that diagnostic criteria are met in studies describing the natural history and/or the results of therapeutic intervention in HRS. Alcohol abuse is a common predisposing factor for the development of HRS. Infection, GI bleed, and aggressive paracentesis were the most common precipitating factors for HRS.

Translocação bacteriana para o pulmão na icterícia obstrutiva experimental em ratos

OBJETIVO: Tem sido demonstrado que a icterícia obstrutiva provoca depressão do sistema imunológico, mudança no padrão de colonização bacteriana dos intestinos e passagem de bactérias da luz intestinal para a circulação porta e sistêmica. Estudo experimental em ratos procurou observar a possibilidade de translocação bacteriana para os pulmões após a ligadura do colédoco. MÉTODO: Foram utilizados 20 ratos Wistar pesando de 178 a 215g, separados aleatoriamente em dois grupos iguais. Nos ratos do grupo I foi feita a ligadura do colédoco e nos do grupo II apenas a manipulação do colédoco com pinça atraumática (sham operation). No sétimo dia de observação os animais foram mortos com superdose de anestésico, sangue foi colhido para dosagem de bilirrubinas e os pulmões ressecados sob condições assépticas. Metade de cada pulmão foi homogeneizada e semeada em meios de cultura ágar McConkey e ágar sangue. A outra metade serviu para exame histopatológico -coloração hematoxilina e eosina. Os dados foram analisados pelo teste t, com significância 0,05. RESULTADOS: revelaram bilirrubina total em média 18,7±3,6 no grupo I e 0,7±0,2 no grupo II. No grupo I foram isoladas colônias de Klebsiela sp nos pulmões de 30% dos animais e E. coli em 20%, e os escores histopatológicos atingiram a média 6,2±2,08. No grupo II não foram detectadas bactérias nos pulmões e os escores do exame histopatológico atingiram 1,8±1,16. A diferença dos dados analisados mostrou-se significativa (p<0,05). CONCLUSÕES: Concluiu-se que a icterícia obstrutiva por ligadura do colédoco em ratos provocou translocação de germes Gram-negativos para os pulmões e resultou em alterações histopatológicas significativas.

Protective effect of melatonin on renal injury of rats induced by bile duct ligation

Oxygen radicals have been implicated in the pathogenesis of renal injury induced by extrahepatic cholestasis. We conduct this study to investigate whether melatonin can have a protective effect against such injury. Either normal saline or gentamicin with or without melatonin was injected into rats that received either a bile duct ligation or a sham operation. The serum levels of malondialdehyde and total antioxidative activity were measured. The kidney was fixed for histologic scoring of renal injury. The serum malondialdehyde level was highest in the rats that received both bile duct ligation and gentamicin injection. Treatment with melatonin significantly increased the serum total antioxidative activity and reduced the serum malondialdehyde concentration. The mean score of renal injury, highest in the rats receiving bile duct ligation and gentamicin injection, was significantly reduced with melatonin treatment. By reducing the systemic oxygen radicals, supplementation with antioxidants exerts a protective effect on the renal injury induced by extrahepatic cholestasis.

The effect of pentoxifylline on the healing of intestinal anastomosis in rats with experimental obstructive jaundice

The aims of this study were (1) to investigate the effect of experimental obstructive jaundice on the healing of intestinal anastomosis, and (2) to investigate the effect of pentoxifylline on the healing of intestinal anastomosis in rats with obstructive jaundice. Obstructive jaundice was induced in rats by the ligation and division of the common bile duct. Four days after this operation, either pentoxifylline or isotonic saline solution was administered intraperitoneally to these jaundiced rats and controls, and then intestinal anastomosis was performed. The concentrations of serum tumor necrosis factor alpha (TNF-alpha) and serum triglyceride of jaundiced and nonjaundiced rats were measured, and the quality of healing was evaluated by measuring the bursting pressure and hydroxyproline content of the anastomoses on the fifth and tenth days of anastomotic healing. Obstructive jaundice resulted in an impaired wound healing of the intestinal anastomosis in the rats. The administration of pentoxifylline to the jaundiced rats resulted in better anastomotic wound healing. The beneficial effects of pentoxifylline on anastomotic healing in rats with obstructive jaundice was attributed to its inhibitor effect on the endotoxin-induced TNF-alpha release from macrophages and monocytes, and the stabilizing effect on the neutrophils.

The effect of oral sodium taurocholate on endotoxemia and intestinal anastomotic wound healing in rats with obstructive jaundice

The effect of sodium taurocholate (ST) on endotoxemia and intestinal anastomotic wound healing in obstructive jaundice was evaluated in a rat model. A total of 108 Wistar rats were divided into three main groups. Thus, 36 animals were given ileal anastomosis (IA) alone (IA group), 36 were given IA with bile duct ligation (BDL) (IA + BDL group), and 36 were given IA with BDL and oral sodium taurocholate (ST) (IA + BDL + ST group). These three main groups were then divided into three equal subgroups, A, B, and C, which were killed on postoperative days (POD) 3, 5, and 9, respectively. In the IA + BDL + ST group, ST was administrated perioperatively and ceased from POD 5 onwards. The anastomotic hydroxyproline level and bursting pressure were significantly lower in the IA + BDL animals compared with the others on POD 3, 5, and 9 (P < 0.008). Endotoxemia was prominent in the IA + BDL group from POD 3 (P = 0.011). After ST was stopped, 42% of the AI + BDL + ST animals developed endotoxemia by POD 9 (P = 0.008). Anastomotic wound healing was better in the IA + BDL + ST group (P < 0.01). These findings suggest that endotoxemia and its adverse effects on wound healing in obstructive jaundice can be prevented by the oral administration of ST.

Obstructive jaundice impairs hepatic sinusoidal endothelial cell function and renders liver susceptible to hepatic ischemia/reperfusion

BACKGROUND/AIMS

Obstructive jaundice is associated with increased surgical morbidity and mortality. While parenchymal injury has been defined in obstructive jaundice, the pathogenesis of hepatic sinusoidal endothelial cell injury in obstructive jaundice is unclear. The aims of this study were to investigate hepatic sinusoidal endothelial cell injury in obstructive jaundice by determining serum hyaluronic acid levels, purine nucleoside phosphorylase/alanine aminotransferase ratios, and hyaluronic acid elimination rate, and also to determine whether hepatic parenchymal cell injury in obstructive jaundice is induced more than in normal liver after hepatic ischemia/reperfusion.

METHODS

Male Wistar rats underwent ligation and division of the common bile duct (obstructive jaundice group) or sham operation (Sham group). Serum hyaluronic acid levels and purine nucleoside phosphorylase/alanine aminotransferase ratios in both groups were examined at intervals up to 21 days after surgery. Hepatic blood flow, permeability, neutrophil accumulation, and hyaluronic acid elimination rates in both groups were measured 14 days after surgery. Changes in serum hyaluronic acid and alanine aminotransferase concentrations were determined after 15 min of hepatic ischemia followed by reperfusion.

RESULTS

Serum hyaluronic acid levels remained elevated after bile duct ligation. Hepatic sinusoidal endothelial cell swelling was observed by electron microscopy, and hepatic permeability was increased 14 days after bile duct ligation in association with neutrophil accumulation. Hepatic blood flow in obstructive jaundice remained unchanged, but hyaluronic acid elimination capacity was less than that in the Sham group. After hepatic reperfusion, the disappearance rate of serum hyaluronic acid in obstructive jaundice was lower, and serum alanine aminotransferase levels were higher than those in the Sham group.

CONCLUSIONS

Our findings suggest that obstructive jaundice impairs sinusoidal endothelial cells and that sinusoidal endothelial cell damage in association with sinusoidal deterioration during obstructive jaundice renders liver susceptible to ischemia/reperfusion relative to normal liver.

Effects of experimental obstructive jaundice on contractile responses of dog isolated blood vessels: role of endothelium and duration of bile duct ligation

1. We examined the effects of experimental obstructive jaundice caused by bile duct ligation (BDL) on vascular smooth muscle function, as well as the underlying mechanisms involved, by recording responses to noradrenaline (NA), 5-hydroxytryptamine (5-HT) and acetylcholine (ACh) in canine isolated renal arteries and to NA in isolated mesenteric arteries in vitro. All studies were performed 7 days after the onset of BDL in renal arteries and 3, 7 and 15 days after the onset of BDL in mesenteric arteries. 2. The maximum contraction evoked by both NA and 5-HT was significantly attenuated with no change in agonist potency (pD2 value) in renal arteries with endothelium obtained from 7 day BDL dogs when compared with those from sham-operated controls (SO). However, the reduction almost disappeared when the endothelium was removed. In contrast, no change in the responsiveness of renal arteries to KCl could be detected at 7 day BDL. Endothelium-dependent relaxations produced by ACh were significantly increased in renal artery rings from 7 day BDL dogs, but the endothelium-independent relaxations produced by papaverine in BDL preparations were not changed when compared with SO controls. 3. At 7 and 15 days after BDL, the Emax values of the mesenteric ring of BDL dogs to NA were significantly lower than that of SO controls, whereas 3 days after surgery there was no significant difference. The pD2 values in arteries obtained from 15 day BDL animals were significantly lower than those obtained from SO control animals. However, no significant changes in pD2 values were seen 3 and 7 days after the onset of BDL. 4. In conclusion, it is suggested that enhanced production and/or release of nitric oxide, mainly of endothelial origin, is associated with reduced vascular responses to contractile agents in experimental obstructive jaundice and that this effect is related to the duration of obstructive jaundice. These results may explain, at least in part, a cause of hypotension that leads to renal failure in patients with obstructive jaundice.

Renal effects of experimental obstructive jaundice: morphological and functional assessment

BACKGROUND

The pathophysiology of renal impairments occurring in obstructive jaundice has been extensively studied, but the underlying mechanism of these derangements remains unclear. The aim of the present study was to investigate the time-related morphological and functional changes occurring in the kidneys of rats undergoing obstructive jaundice.

METHODS

Histological examination, renal function assessment and determination of (Na + K)-ATPase activity were performed in the kidneys of rats 7, 14, and 21 days following bile duct ligation (BDL) or sham operation (sham).

RESULTS

Glomerular filtration rate was unaffected by BDL throughout the period of the study. Tubular effects occurred at days 7 and 14, being more marked at day 7, and consisted of an increase of about twice in the fractional excretion of sodium and chloride, paralleled by a decreased proximal and distal tubular reabsorption of sodium of about 50 and 40%, respectively. Natriuresis was consistent with augmentation of osmolar clearance but it was not associated with changes in the activity of renal (Na+ + K+)-ATPase. The ability to dilute urine was impaired at days 14 and 21 after BDL. Additionally, these effects were accompanied by decreased tubulointerstitial fibrosis and vasodilation of inner medullary capillaries. At day 21, the parameters of tubular function in BDL and sham groups were not significantly different.

CONCLUSIONS

These data support the view that raised natriuresis taking place in the initial 2 weeks following BDL is due mainly to tubular effects. The contribution of hemodynamic, paracrine and humoral mediators is discussed.

Myocardial high-energy phosphates and hepatic redox state in jaundiced rats

BACKGROUND

The mechanism underlying the fatal complications in jaundiced states after shock has not been fully clarified. The present study was designed to examine the effect of hemorrhagic shock on myocardial high-energy phosphate stores and the arterial ketone body ratio (AKBR:acetoacetate/beta-hydroxybutyrate), which reflects the redox state of the liver mitochondria, in normal and jaundiced rats.

MATERIALS AND METHODS

At 1 week after ligation of the common bile duct, hemorrhagic shock was induced by exsanguination (mean arterial blood pressure = 40 mmHg) and maintained for 2 h. Serial changes in AKBR were measured. The myocardial adenine nucleotides phosphocreatine (PCr) and inorganic phosphate (Pi) were determined before and after hemorrhagic shock.

RESULTS

Before shock, myocardial ATP in the jaundiced group was lower than that in the sham group. However, the myocardial PCr levels in the two groups did not differ. After reinfusion of the shed blood, ATP and PCr recovered to the preshock levels in the sham group. However, ATP and PCr were further increased in the jaundiced group. At 60 min after reinfusion, AKBR recovered to the normal level in the sham group, but decreased below 0.7 in the jaundiced group. Metabolic acidosis was more severe in the jaundiced group than in the sham group.

CONCLUSIONS

The decrease in AKBR indicated irreversible metabolic acidosis. As a result, fatal circulatory failure occurred, although the phosphoenergetic level in the myocardium was sufficiently maintained.

The role of ursodeoxycholic acid in bile acid-mediated kidney fragment toxicity

Elevated levels of bile acids are thought to play an important role in the renal failure of patients with obstructive jaundice undergoing surgery. In contrast, ursodeoxycholic acid (UDA) is widely used to improve cholestasis and has been proposed as protective bile acids and antioxidant. The present study employs kidney fragments to determine the role of reactive oxygen species (ROS) in the mechanism of toxicity of hydrophobic bile acids and to determine the nephroprotectant properties of UDA against the hydrophobic bile acids. The hydrophobic bile acids chenodeoxycholic (200 microM) and deoxycholic acid (200 microM) significantly (P<0.05) increased lactate dehydrogenase leakage (LDH) from glomerular fragments from 2.7+/-0.4 to 5.03+/-0.23 and 4.66+/-0.37 (micromol NADH consumed/min/mg protein) for chenodeoxycholic and deoxycholic acid respectively. Preincubating the fragments with UDA (500 microM) did not prevent the leakage of LDH caused by the bile acids. The level of lipid peroxidation was not increased in fragments exposed to either ursodeoxycholic (0-500 microM), lithocholic (0-100 microM), chenodeoxycholic (0-500 microM) or deoxycholic acid (0-500 microM). Furthermore UDA (500 microM) did not prevent the increase in lipid peroxidation caused by tert-butyl hydroperoxide (0-1000 microM) in the fragments. These results suggest that hydrophobic bile acids do not cause lipid peroxidation in kidney fragments and that UDA is neither capable of preventing the loss of membrane integrity induced by hydrophobic bile acids or acting as an antioxidant in kidney fragments.

Mucin secretion by the human colon cell line LS174T is regulated by bile salts

We recently reported that bile salts play a role in the regulation of mucin secretion by cultured dog gallbladder epithelial cells. In this study we have examined whether bile salts also influence mucin secretion by the human epithelial colon cell line LS174T. Solutions of bile salts were applied to monolayers of LS174T cells. Mucin secretion was quantified by measuring the secretion of [3H]GlcNAc labeled glycoproteins. Both unconjugated bile salts as well as taurine conjugated bile salts stimulated mucin secretion by the colon cells in a dose-dependent fashion. Hydrophobic bile salts were more potent stimulators than hydrophilic bile salts. Free (unconjugated) bile salts were more stimulatory compared with their taurine conjugated counterparts. Stimulation of mucin secretion by LS174T cells was found to occur at much lower bile salt concentrations than in the experiments with the dog gallbladder epithelial cells. The protein kinase C activators PMA and PDB had no stimulatory effect on mucin secretion. We conclude that mucin secretion by the human colon epithelial cell line LS174T is regulated by bile salts. We suggest that regulation of mucin secretion by bile salts might be a common mechanism, by which different epithelia protect themselves against the detergent action of bile salts, to which they are exposed throughout the gastrointestinal tract.

Significance of serum delta-bilirubin in patients with obstructive jaundice

BACKGROUND

Delta-bilirubin is a bilirubin covalently bound with albumin, which is nontoxic and excreted neither in urine nor in bile. We previously reported that the percentage of delta-bilirubin increased after biliary drainage and that the rapidly excretable bilirubin fraction (total minus delta-bilirubin) was a better parameter to predict the effectiveness of biliary decompression in the dog model. The aim of the present study was to elucidate whether it is applicable to humans.

MATERIALS AND METHODS

The serum bilirubin concentration was measured and its fractions were analyzed by high-performance liquid chromatography in 22 patients with obstructive jaundice before and after biliary drainage. In addition, the patients were subgrouped into good and poor drainage groups according to the decline index of serum bilirubin to examine the significance of delta-bilirubin.

RESULTS

The concentration of total bilirubin decreased from 14.1 mg/dl before biliary drainage to 5.4 mg/dl 28 days after drainage. During this period, the percentage of conjugated bilirubin steeply declined from 47.1 to 8.8% and that of excretable bilirubin from 63.4 to 28.6%. In contrast, the proportion of serum delta-bilirubin increased from 36.6 to 71.4%. There was an inverse correlation between percentage of delta-bilirubin and total bilirubin concentration (r = -0.69, P < 0.01). In the good drainage group, the percentage of delta-bilirubin increased above 60% within 7 days after biliary drainage, but it did not reach 60% by 28 days in the poor drainage group. A decreasing rate of total bilirubin minus delta-bilirubin, the excretable bilirubin fraction, was a better index than that of total bilirubin to assess the efficacy of biliary drainage (P< 0.01).

CONCLUSIONS

The increase in the percentage of serum delta-bilirubin indicates an effectiveness of biliary drainage in man. An analysis of serum delta-bilirubin for 7 days can distinguish the good drainage patients from the poor drainage patients.

The relationship between sodium chloride concentration and bile acid cytotoxicity in cultured kidney cells

Patients with obstructive jaundice suffer an increased incidence of mortality from post operative renal failure, which may be related to elevated circulating bile salts. This study assesses the effects of increased ionic strength (similar to that found in the kidney inner medulla) on bile salt critical micellar concentration (CMC) and cytotoxicity to renal medullary epithelial primary cultures and MDCK and NRK cell lines representing the distal and proximal tubular cells respectively. The CMC of chenodeoxycholic acid decreased from 2.86 +/- 0.07 (in isotonic Earle's Hepes buffer) to 2.30 +/- 0.07, 1.99 +/- 0.09 and 1.46 +/- 0.08 mM following the addition of 150, 250 and 500 mM NaCl. Similarly, the CMC of deoxycholic acid was reduced from 3.18 +/- 0.1 to 2.84 +/- 0.1, 2.26 +/- 0.1 and 1.79 +/- 0.09 mM by the addition of 150, 250 and 500 mM NaCl. Increasing the ionic strength of the culture medium of medullary epithelial cells by the addition of 150 mM NaCl, decreased viability by 39% (p < 0.01), 24% (p < 0.001) and 40% (p < 0.001) for lithocholic (25 microM), chenodeoxycholic (100 microM) and deoxycholic acids (100 microM), respectively. A similar increase in the ionic strength of the culture medium of MDCK cells decreased viability by 79% (p < 0.01), 46% (p < 0.01) and 15% (p < 0.01) for lithocholic (15 microM), chenodeoxycholic (100 microM) and deoxycholic (50 microM), respectively. Adding 200 mM urea to medium supplemented with 150 mM NaCl (to further increase osmolality but not ionic strength) had no effect on the cytotoxicity bile salts in MDCK cells. The addition of 150 mM NaCl to the culture medium of NRK cells resulted in a decrease viability of 15% (p < 0.01), 27% (p < 0.01) and 60% (p < 0.01) following exposure to either lithocholic (15 microM), chenodeoxycholic (50 microM) or deoxycholic acids (50 microM) respectively. These results show that increasing NaCl concentrations lowers CMC of bile salts and increase cytotoxicity in medullary epithelial primary, MDCK and NRK cells. This suggests that the high NaCl levels in the kidney inner medulla would reduce bile salt CMC such that they could damaged renal cells. This may, in part, explain the increased susceptibility of the kidney during obstructive liver disease.

Lactulose and renal failure

The introduction of lactulose as a new therapeutic agent for treatment of hepatic encephalopathy was a major breakthrough in this field. It was hypothesized that lactulose might prevent postoperative renal impairment after biliary surgery in patients with obstructive jaundice. The presumable mechanism purported was the diminished endotoxinemia by lactulose. Unfortunately, such a reno-protective effect has not been shown conclusively until now in clinical studies. In chronic renal failure lactulose is known to promote fecal excretion of water, sodium, potassium, amonium, urea, creatinine and protons. Thus, lactulose could be useful for the treatment of chronic renal failure. However, compliance to the therapy represents a major problem.

Role of the gut in the pathophysiology of extrahepatic biliary obstruction

BACKGROUND

Gram negative septic events are the commonest source of morbidity and mortality as a result of surgery in jaundiced patients. The large intestine provides the major source of Gram negative bacteria in mammals and is implicated in the pathogenesis of systemic endotoxaemia in obstructive jaundice. Bile salts have an important part in maintaining indigenous microecological homeostasis through their emulsifying properties.

AIMS

The aim was to investigate the effects of biliary obstruction and isolated external biliary diversion on gastro-intestinal structure and caecal bacterial flora in relation to bacterial translocation.

METHOD

Six groups of adult male Wistar rats were studied (no operation, sham operated, and bile duct ligated (BDL) for one and three weeks and a choledocho-vesical fistula (CDVF) for one week). At the end of the study period plasma was assayed for evidence of endotoxaemia and the animals were tested for bacterial translocation to the mesenteric lymph node complex (MLNC), liver, lungs, and spleen. Quantitative and qualitative bacteriological studies were performed on the caecal contents and segments of colon and terminal ileum were washed and prepared for histological assessment.

RESULTS

Bacterial translocation was significantly increased in the BDL1 (68.8%) and BDL3 (60%) groups compared with the sham1 (6.3%), sham3 (9.1%), No operation (0%), and CDVF1 (16.7%) groups. Although translocation was more pronounced in the BDL1 group, this was almost exclusively to the MLNC compared with the more widespread translocation to other organs in the BDL3 group. The BDL3 group was the only group with significantly raised concentrations of endotoxin and anticore glycolipid. The caecal Gram negative aerobic counts were significantly increased in the BDL1 and CDVF1 groups compared with all other groups. There was evidence of structural abnormalities in the terminal ileum of rats jaundiced for three weeks, but not in the other groups.

CONCLUSIONS

Biliary obstruction for one and three weeks promotes bacterial translocation although the mechanisms may be different. Absence of intralumenal bile results in a significant but self limiting increase in the Gram negative aerobic population, which may account for translocation in the early stages of biliary obstruction. As the duration of biliary obstruction increases systemic endotoxaemia is a consistent feature which, combined with factors such as immunological depression and physical disruption of gut barrier function, may promote bacterial translocation perpetuating systemic sepsis.

Intestinal barrier dysfunction in clinical and experimental obstructive jaundice and its reversal by internal biliary drainage

Intestinal mucosal barrier function in obstructive jaundice was assessed in an animal model and in patients. The effect of internal biliary drainage in patients was also examined. Bile duct ligation for 1 week in the rat resulted in significant bacterial translocation (in seven of 12 animals following ligation versus none of the shamoperated controls, P < 0.01). Intestinal permeability, measured by the urinary recovery of orally administered polyethylene glycol, was also significantly increased (+66.2 per cent for ligation versus -11.6 per cent for sham, P < 0.01). A prospective study was performed on 33 patients with obstructive jaundice undergoing internal biliary drainage, and results were compared with those in six non-jaundiced patients undergoing laparotomy or endoscopic retrograde cholangiopancreatography and in 11 health volunteers. The lactulose: mannitol ratio was used as an intestinal permeability index. Mean(s.e.m.) intestinal permeability assessed before operation was significantly increased in jaundiced patients compared with control patients (0.050(0.010) versus 0.016(0.003), P < 0.005). The mean(s.e.m.) lactulose: mannitol ratio in the healthy volunteers was 0.020(0.003), which was similar to that in control patients. In the jaundiced group of patients the intestinal permeability index fell to within normal levels after 28 days of internal biliary drainage (0.050 before operation versus 0.021 at 28 days, P < 0.02). These data indicate that intestinal barrier function is impaired in obstructive jaundice and that this impairment is reversed by return of bile to the gastrointestinal tract.

Biliary decompression promotes Kupffer cell recovery in obstructive jaundice

BACKGROUND

Jaundiced patients undergoing surgical procedures have an increased risk of Gram negative sepsis with potential morbidity and mortality. Depressed Kupffer cell clearance capacity (KCCC) predisposes jaundiced patients to endotoxaemia and its sequelae. Biliary decompression remains the main therapeutic strategy in obstructive jaundice.

AIMS

This study investigates the efficacy of internal (ID) and external biliary drainage (ED) on KCCC in an experimental model of extrahepatic biliary obstruction.

METHODS

Adult male Wistar rats (250-300 g) were assigned to one of six groups: sham operated, where the bile duct was mobilised but not divided; bile duct ligation (BDL) for three weeks, and sham operated or BDL for three weeks followed by a second laparotomy and further 21 days of ID or ED, by way of choledochoduodenostomy or choledochovesical fistula respectively. KCCC was measured using an isolated hepatic perfusion technique with FITC labelled latex particles (0.75 mu) as the test probe. Plasma was assayed for bilirubin, endotoxin, and anticore glycolipid antibody (ACGA) concentrations.

RESULTS

Jaundiced rats had reduced KCCC (p < 0.001), increased concentrations of ACGA (p < 0.001), and endotoxin (p < 0.001) compared with controls. Biliary drainage for three weeks produced a recovery in KCCC and normalisation of endotoxin and ACGA concentrations, however, external drainage was less effective than ID (p < 0.01).

CONCLUSIONS

These data support the hypothesis that endotoxaemia and its mediated effects are integral in the pathophysiology of jaundice. Furthermore, a short period of internal biliary drainage is a useful therapeutic strategy in restoring Kupffer cell function and negating systemic endotoxaemia and consequent complications in biliary obstruction.

Hepatic tumor necrosis factor-alpha production and distant organ dysfunction in a murine model of obstructive jaundice

BACKGROUND

Multisystem organ dysfunction frequently occurs following obstructive jaundice, but its etiology remains unclear. This study was undertaken to evaluate the role for endogenous tumor necrosis factor-alpha (TNF-alpha) production in the renal and pulmonary injury that accompanies obstructive jaundice.

METHODS

Two hundred and twenty C57BL/6 mice underwent ligation and division of the common bile duct or a sham celiotomy. The animals were randomized to receive either placebo or 1 mg/kg BW (low dose) or 15 mg/kg BW (high dose) of a novel TNF-alpha inhibitor comprised of two extracellular domains of the p55 TNF receptor linked together with polyethylene glycol. Serum bilirubin, creatinine, and urea nitrogen were determined. TNF-alpha bioactivity in plasma and organs was determined using the WEHI 164 clone 13 cytotoxicity assay. The TNF-alpha messenger RNA was detected by reverse transcriptase-polymerase chain reaction. Neutrophil infiltration into the lungs and kidney were quantitated by the myeloperoxidase assay.

RESULTS

Common bile duct ligation and division resulted in rapid and sustained increases in serum bilirubin, creatinine, and urea nitrogen, peaking 2 to 5 days later. Hepatic TNF-alpha production was detected in the liver within 8 hours following obstructive jaundice, but TNF-alpha production could not be detected in the kidney or lung at any time point. Increased neutrophil infiltration occurred in the lung following obstructive jaundice peaking 5 days after obstructive jaundice. This neutrophil infiltration into the lungs could be partially inhibited (62%, P < 0.05) by administration of the novel TNF inhibitor. In contrast, neither renal nor hepatic dysfunction were affected by TNF-alpha blockade.

CONCLUSIONS

Hepatic TNF-alpha production is an integral component of the response to obstructive jaundice. A TNF-alpha-mediated inflammatory response occurs in the lungs as a result of obstructive jaundice; however, renal and hepatic dysfunction do not appear to be TNF-alpha dependent since they cannot be affected by TNF-alpha blockade.

Plasma cytokine levels and monocyte activation in patients with obstructive jaundice

Some monocytic cytokines are important immune regulators. We have investigated cytokine production by monocytes and the blood levels of IL-1 beta, IL-6, TNF alpha, and TGF beta, in patients with obstructive jaundice. The supernatant from LPS stimulated monocytes from jaundiced patients released significantly increased quantities of TNF alpha by both bioassay and radioimmunoassay (RIA) (12.4 +/- 2.5 fmol/mL and 32.6 +/- 8.3 fmol/mL, respectively, for jaundice, compared with 1.6 +/- 0.3 fmol/mL and 2.4 +/- 0.5 fmol/mL respectively for controls, and also of IL-6 (54.8 +/- 5.0 fmol/mL in jaundice compared with 35.6 +/- 5.0 fmol/mL for controls). The production of IL-1 beta and TGF beta by stimulated monocytes was unchanged. Jaundiced patients had significantly higher plasma TGF beta, but TNF alpha and IL-1 beta were below the limits of detection. The highest monocyte TNF alpha and IL-6 levels were seen in malignant disease patients, especially those with a poor immediate prognosis. We conclude that the production of some cytokines by monocytes is up-regulated in patients with obstructive jaundice.