Endotoxaemia and renal failure in cirrhosis and obstructive jaundice

The role of bile acids in the development of endotoxemia during obstructive jaundice in the rat

The role of bile acids in the development of endotoxemia during obstructive jaundice was studied in rats. Endotoxin was not found in portal and peripheral plasma of control rats. The bile ducts of seven rats were ligated. On day 7 following bile duct ligation, six animals showed portal endotoxemia and five peripheral. Oral administration of sodium ursodeoxycholate reduced this frequency to 1/7 for portal plasma and 0/7 in the case of peripheral plasma. Subsequently the influence of a bile salt mixture (85% taurocholate, 15% taurodeoxycholate) on the binding and uptake of Salmonella abortus equi lipopolysaccharide by cultured rat Kupffer cells was studied. In control preparations, the percentage cell-associated lipopolysaccharide increased with time and reached a plateau after about 2 h of incubation at 37 degrees C. In the presence of 0.3, 0.6 and 1 mumol bile salts/ml the cell-associated lipopolysaccharide was about 5%, 13% and 29% lower, respectively, of that in control cultures. Tauroursodeoxycholate (1 mM) did not inhibit the lipopolysaccharide uptake by cultured rat Kupffer cells. Based on these observations, it is likely that both phenomena, i.e., (a) the low amount of bile acids in the intestines and (b) the high serum bile acid level, account for the high frequency of endotoxemia in the peripheral blood during obstructive jaundice.

Lactulose inhibits endotoxin induced tumour necrosis factor production by monocytes. An in vitro study

Preoperative oral treatment with lactulose is used to prevent complications after surgery in patients with obstructive jaundice. The effect is perhaps the result of an inactivation of gut derived endotoxins but the exact mechanism of action is, however, unknown. Tumour necrosis factor is an important mediator of endotoxin toxicity. The cytokine tumour necrosis factor is mainly produced by mononuclear phagocytes. In this study, the effect of lactulose on the endotoxin induced tumour necrosis factor release by monocytes was investigated. The direct effect of lactulose on endotoxin was tested in a chromogenic limulus amoebocyte lysate assay. Polymyxin B a known inactivator of endotoxin was used as control in both experiments. Lactulose has a limited capacity to inactivate endotoxin as measured in the endotoxin assay. In contrast lactulose significantly reduced endotoxin induced tumour necrosis factor production by monocytes. In conclusion lactulose inhibits tumour necrosis factor production by a direct inhibitory effect on monocytes, rather than by inactivation of endotoxin. Because tumour necrosis factor is an important mediator of endotoxin toxicity, this inhibitory effect could explain the beneficial effect of lactulose in obstructive jaundice.

Suppression of cellular immunity in obstructive jaundice is caused by endotoxins: a study with germ-free rats

The increased susceptibility to infections after surgery in jaundiced patients is considered to be caused by an impairment of cellular immunity and/or nutritional status. Endotoxins are suggested to play a role in the pathogenesis. However, the mechanism of action is unknown. Germ-free rats were used to study the effect of biliary obstruction in a model with negligible amounts of endotoxin. Cellular immunity, production of tumor necrosis factor (as a mediator of endotoxin toxicity) by peritoneal macrophages, and the nutritional status were assessed. Significant suppression of cellular immunity was found in conventional rats with obstructive jaundice. In contrast, cellular immunity was not suppressed in jaundiced germ-free rats. Large amounts of tumor necrosis factor were spontaneously secreted by peritoneal macrophages of jaundiced conventional rats, whereas macrophages from jaundiced germ-free rats did not. Moreover macrophage activation (expressed in tumor necrosis factor production) was significantly related to suppression of cellular immunity. Weight changes and depression of albumin levels were not different in germ-free and conventional rats after bile duct ligation. The data presented indicate that suppression of cellular immunity in obstructive jaundice is caused by endotoxins, whereas the impaired nutritional status seems to not be affected by the presence of endotoxins.

Obstructive jaundice promotes bacterial translocation from the gut

Experiments were performed to determine if obstructive jaundice promotes the translocation of bacteria from the gastrointestinal tract to visceral organs. Three groups of mice were studied: control (n = 20), sham ligated (n = 28), and bile duct ligated (n = 33). The sham-ligated group underwent laparotomy and manipulation of the portal region, whereas the ligated group had their common bile ducts ligated. Seven days later, the mice were killed, their organs cultured, and the gastrointestinal tract examined histologically. The bilirubin levels of the ligated group (18.7 mg/dL) were elevated compared with the other groups (0.5 mg/dL) (p less than 0.05). The incidence of bacterial translocation was higher in the ligated (33%) than in the control (5%) or sham-ligated (7%) groups (p less than 0.05). Since bile is important in binding endotoxin and maintaining a normal intestinal microflora, cecal bacterial populations were quantitated. The cecal levels of gram-negative, enteric bacilli were 100-fold higher in the bile duct-ligated mice in which bacterial translocation occurred (p less than 0.05), indicating that intestinal bacterial overgrowth was a major factor responsible for bacterial translocation. The mucosal appearance of the intestines from the control and sham-ligated groups was normal. In contrast, subepithelial edema involving the ileal villi was present in the ligated group. In conclusion, the absence of bile within the gastrointestinal tract allows intestinal overgrowth with enteric bacilli and the combination of bacterial overgrowth and mucosal injury appears to promote bacterial translocation.

Perioperative change of plasma endotoxin levels in early infants

As a preliminary study to elucidate the relationship of endotoxemia to postoperative morbidity, the plasma endotoxin levels in 64 surgical neonates were quantitated by the chromogenic limulus test (Toxicolor test; Seikagaku Kogyo, Tokyo, Japan). The preoperative levels of plasma endotoxin were 64 +/- 59 pg/mL in the group of infants with perforated peritonitis (n = 9), 63 +/- 51 pg/mL in the group of infants with gastroschisis (n = 7), and 15 +/- 16 pg/mL in the group of infants with ileus (n = 28), while the mean level was 6 +/- 5 pg/mL in the remaining 20 surgical neonates who had no signs of ileus or peritonitis. In the serial determination of plasma endotoxin in 28 neonates, the levels on the first postoperative day increased significantly compared with the preoperative levels (16 +/- 18 pg/mL to 46 +/- 25 pg/mL, P less than .01). They decreased gradually to 8 +/- 5 pg/mL within a week in 15 neonates who had no postoperative complications. However, in 13 neonates who had postoperative complications such as wound infection or postoperative ileus, the postoperative levels of plasma endotoxin increased to a much higher level and remained there. In this article the relationship of clinical endotoxemia to postoperative thrombocytopenia and hyperbilirubinemia is analyzed, and the usefulness of evaluating endotoxemia in surgical neonates is discussed.

Endotoxaemia and hepatic injury in obstructive jaundice

To examine whether endotoxaemia contributes to the development of bile infarction and whether obstructive jaundice enhances endotoxin hepatotoxicity, the present study was undertaken in rats. The development of bile infarction and the elevation of serum transaminase activities in rats following ligation of the common bile duct were not prevented by administration of polymyxin B, neomycin, or lactulose, which have anti-endotoxin properties. Moreover, the morphological and functional changes in obstructive jaundice were not enhanced by administration of endotoxin. These data indicate that endotoxaemia does not contribute to the development of bile infarction. On the other hand, the administration of a small dose of endotoxin to rats with biliary obstruction--a dose which does not induce abnormalities of liver function tests or any morphological changes in the liver in non-jaundiced rats--led to focal hepatocellular coagulative necrosis and elevation of serum transaminase levels. These data indicate that endotoxin-induced hepatic injury is potentiated in obstructive jaundice.

Bile acids inhibit endotoxin-induced release of tumor necrosis factor by monocytes: an in vitro study

Endotoxins play an important role in the pathogenesis of complications of surgery in obstructive jaundice. Preoperative treatment with orally administered deoxycholic acid prevented endotoxin-related complications, such as renal malfunction. Other bile acids, however, were less effective, and the mechanism of action is not known. Endotoxin toxicity is considered to be largely mediated by tumor necrosis factor/cachectin, a cytokine release by mononucler phagocytes. Therefore, we studied the influence of different bile acids on endotoxin-induced tumor necrosis factor production by monocytes in vitro. Bile acids inhibit tumor necrosis factor production through a direct inhibitory effect on the monocytes. Deoxycholic acid was the most effective, chenodeoxycholic acid was less effective and ursodeoxycholic acid was ineffective in the concentrations used. Bile acids did not inactivate endotoxin as measured in a chromogenic Limulus amebocyte lysate assay. The therapeutic effect of bile acids in obstructive jaundice can be explained by an inhibition of endotoxin-induced tumor necrosis factor release by mononuclear phagocytes.

Urinary prostaglandins and renal function in obstructive jaundice

Changes in urinary prostaglandin E2 (PGE2), 6-keto PGF1 alpha, and thromboxane (TXB2) excretion in 12 patients with obstructive jaundice were observed in relation to renal function and the renin-angiotensin (R-A) system. In obstructive jaundice before percutaneous biliary drainage the creatinine clearance (CCr) was significantly lower (p less than 0.001) and the PGE2 and plasma angiotensin II (AII) concentrations were significantly higher (p less than 0.005 and p less than 0.005, respectively) than those in normal subjects. Both 6-keto PGF1 alpha and TXB2 were widely distributed. When CCr returned to normal after drainage, PGE2 and plasma AII also returned to normal, but when CCr decreased after drainage, PGE2 and plasma AII increased. Before drainage, PGE2 correlated negatively with CCr (r = -0.72, p less than 0.01) and positively with plasma AII(r = 0.69, p less than 0.02). 6-Keto PGF1 alpha correlated positively with serum total bilirubin (r = 0.66, p less than 0.02). The percentage change in PGE2 after drainage correlated negatively with that in CCr (r = -0.95, p less than 0.005). The percentage chang in plasma AII correlated positively with that in urine PGE2 (r = 0.94, p less than 0.005) and negatively with that in CCr (r = -0.85, p less than 0.02). These results suggest that PGE2 is closely related to the R-A system and might assist in the maintenance of renal circulation in obstructive jaundice.

Endotoxemia during percutaneous manipulation of the obstructed biliary tree

Fourteen patients undergoing percutaneous biliary manipulation were studied on 21 occasions. Using a chromogenic limulus-based assay technique, peripheral endotoxin concentration prior to the procedure was found to be 6.1 +/- 9 pg/ml, increasing to 30.7 +/- 26 pg/ml after the procedure (p less than 0.001). Fourteen of 21 bile cultures and only 1 of 21 blood cultures drawn during the procedure were positive for bacterial growth. There was a clinically modest but statistically significant decrease in blood pressure (p less than 0.05), an increase in temperature (p less than 0.01), and an increase in creatinine concentration (p less than 0.05) before and after biliary manipulation. The presence of infected bile and the preprocedure bilirubin level predicted development of endotoxemia.

Non-septic endotoxemia in cirrhotic patients

We have found that endotoxemia detected by conventional LCT (limulus colorimetric test) in patients with liver diseases could not be detected by endotoxin-specific LCT at all, and proposed that this beta-glucan like activity (BGLA) should be termed as non-septic endotoxemia, distinguishing it from septic endotoxemia seen in gram-negative sepsis. In this study, we investigated non-septic endotoxemia through the clinical course of 8 cirrhotic patients. Non-septic endotoxemia appeared at the onset of DIC but tended to decline in level in the late terminal stage. This phenomenon cannot be consistent with the "spillover" theory which explains the mechanism of endotoxemia without sepsis in liver disease. We think it is an urgent problem to elucidate the nature of BGLA in liver disease, without recourse to the "spillover" theory.

Gentamicin nephrotoxicity in extrahepatic cholestasis: modulation by dietary calcium

The present study was designed to test the hypothesis that the presence of a specific hepatobiliary disease, namely common bile duct obstruction, in the absence of other risk factors will exacerbate gentamicin nephrotoxicity. Furthermore, since bile duct ligation decreases urinary calcium excretion, we studied the role of calcium supplementation in the prevention of gentamicin nephrotoxicity in this model. Male Sprague-Dawley rats were allocated to sham groups and common bile duct ligation groups. Gentamicin at 40 and 100 mg per kg per day for 5 days induced a more severe azotemia in common bile duct ligation animals than in sham controls. Furthermore, higher levels of renal gentamicin were found in common bile duct ligation rats than in sham rats early in the course of therapy, at its termination and during the recovery period. Pretreatment of common bile duct ligation animals with dietary calcium supplementation significantly attenuated gentamicin nephrotoxicity and the increased renal gentamicin accumulation, whereas initiation of calcium supplementation concurrent with gentamicin administration had no salutary effect. We conclude that experimental extrahepatic cholestasis in the rat, in the absence of any other factor, potentiates gentamicin nephrotoxicity. The effect is prevented by pretreatment with dietary calcium supplementation but is not modified by concurrent administration of a high-calcium diet.

The role of bile acids in the reduction in lipopolysaccharide uptake by cultured rat Kupffer cells

The influence of bile salts on the binding and uptake of Salmonella abortus equi lipopolysaccharide by cultured Kupffer cells was studied. In control preparations, the percentage of cell-associated lipopolysaccharide increased with time and reached a plateau after about 2 h incubation at 37 degrees C. About 1.2 micrograms lipopolysaccharide was associated with 10(6) Kupffer cells at this time interval. In the presence of 0.3, 0.6 and 1 mumol bile salts/ml the cell-associated lipopolysaccharide was respectively, about 5%, 13% and 29% lower than in control cultures. In the presence of 1 mumol bile salts/ml, the association of lipopolysaccharide to cells at 0 degrees C was about 25% lower than in controls. Preincubation of Kupffer cells with 1 mumol bile salts/ml, with or without lipopolysaccharide, did not affect cell-associated lipopolysaccharide after removal of the bile salts. The rate of secretion of radioactivity by Kupffer cells was not influenced by the presence of bile salts during the uptake or the secretion periods. Bile acids proved to inactivate lipopolysaccharide. From these observations it was concluded that low concentrations of bile salts influence the binding and uptake of lipopolysaccharide by Kupffer cells. It was, therefore, considered likely that, in patients with obstructive jaundice, the high serum bile acid level accounts for spill-over of portal lipopolysaccharide into the systemic blood.

Effects of sera from patients with obstructive jaundice on the generation of oxygen intermediates by normal polymorphonuclear leukocytes

Recently it has been suggested that oxygen intermediates play an important role in the pathogenesis of tissue damage. The effect of sera from patients with obstructive jaundice on the generation of oxygen intermediates by normal polymorphonuclear leukocytes (PMNs) was investigated. Sera from patients with obstructive jaundice increased superoxide anion (O2-), hydrogen peroxide (H2O2) and hydroxol radical (OH.) generation compared with sera from healthy individuals or patients with biliary tract stones and/or tumors of the biliary tract or pancreas (without obstructive jaundice). In particular, the hydroxyl radical, which is one of the most potent oxidants capable of causing tissue damage, was produced in large quantities. Sera from patients with obstructive jaundice have a strong capacity to induce production of oxygen intermediates from PMNs, and oxygen intermediates may play a role in the pathogenesis of hepatic and other organ injury in obstructive jaundice.

Antiserum to endotoxin in hemorrhagic shock

Antiserum to Escherichia coli J5, a mutant endotoxin (LPS) which contains only core determinants, has proven effective in reducing mortality from endotoxic shock due to a wide variety of gram-negative bacteria. Twenty New Zealand white rabbits with coliforms in the gut were subjected to hemorrhagic shock of 36 mm Hg for 3 hr. Treated rabbits were resuscitated with 15 cc of rabbit J5 antiserum (hemagglutinating antibody titer against J5 lipopolysaccharide of 1:1024), remaining shed blood, and lactated Ringer's to achieve a mean arterial blood pressure (MABP) within 20% of baseline. The control group was similarly resuscitated but received 15 cc normal rabbit serum (titer 1:2). Catheters were removed and rabbits were returned to their cages until death or 5 days of survival. Hemodynamic parameters (heart rate, MABP, cardiac output, and total peripheral resistance) did not differ significantly between groups. However, six treated rabbits survived 5 days (60%) and no control rabbit lived past the third postexperimental day (P less than 0.019). Our data suggest that systemic endotoxemia may contribute to morbidity and mortality in severe hemorrhagic shock.

Surgical morbidity and mortality in one hundred and twenty-nine patients with obstructive jaundice

One hundred and twenty-nine jaundiced patients were operated upon for the relief of benign and malignant bile duct obstruction during a 10-year period, 1977-86. The overall mortality was 4.7 per cent but increased to 9.1 per cent in patients with a serum bilirubin greater than 300 mumol/l. In all, 46.5 per cent of patients had a rise in postoperative creatinine but renal dysfunction occurred in only 4.7 per cent. Wound infection developed in 3.1 per cent of patients and appeared unrelated to infected bile; 3.9 per cent of patients were treated for postoperative septicaemic episodes. The low morbidity and mortality observed suggests that preoperative biliary drainage need not be considered in routine surgical practice if simple measures to maintain urine flow and prevent postoperative sepsis are used.

Endotoxin levels measured by a chromogenic assay in portal, hepatic and peripheral venous blood in patients with cirrhosis

Endotoxin concentrations were measured in the portal, hepatic and peripheral venous blood of two groups of patients with cirrhosis using a limulus-based chromogenic assay. The high sensitivity of chromogenic detection allowed measurement of endotoxin as low as 10 to 15 pg per ml, an order of magnitude greater than previously possible by gelation studies. Group 1 consisted of 56 patients with cirrhosis undergoing angiographic evaluation. In this group, there was wide variability in hepatic venous concentration [73 +/- 110 pg per ml (mean +/- S.D.)] and peripheral venous concentration [31 +/- 58 pg per ml]. However, paired t test showed peripheral venous concentration was significantly (p less than 0.001) lower than hepatic venous concentration. Neither hepatic or peripheral venous endotoxin levels correlated significantly with a variety of clinical, biochemical or radiological parameters. Group 2 consisted of 21 patients with cirrhosis undergoing shunt surgery. Endotoxin levels again showed a wide range, with portal venous concentration (142 +/- 167 pg per ml) and simultaneous peripheral venous concentration (82 +/- 150 pg per ml). Paired t test in this group showed a significant (p less than 0.001) portal to peripheral venous gradient. This study showed the feasibility of measuring endotoxin in plasma to low concentrations by a chromogenic assay technique. It supports the concept of relatively high levels of endotoxin in the portal circulation. In the presence of liver disease, systemic endotoxemia occurs, which is augmented by stressful situations.

Endotoxemia in obstructive jaundice. Observations on cause and clinical significance

Perioperative endotoxemia was detected in 24 of 40 patients who underwent operation for obstructive jaundice (bilirubin level greater than 5.8 mg/dl). Endotoxemia was associated with an increased admission serum bilirubin level (p less than 0.05) and white blood cell count (p less than 0.05) and a decreased hematocrit value (p less than 0.05), but there was no significant association with other established preoperative risk factors. Patients with preoperative endotoxemia had a decreased immunoglobulin M anti-J5 endotoxin titer (p less than 0.05) and a decreased serum bile acid concentration (p less than 0.05). Preoperative endotoxemia was associated with reduced creatinine clearance before and after operation (p less than 0.05). There was no association between endotoxemia and clinical sepsis, gram-negative infection, or small-bowel colonization. Patients who died had increased preoperative serum fibrin degradation products (p less than 0.05).

Circulating immune complex, endotoxin, and biliary infection in patients with biliary obstruction

Immunoglobulin A-containing circulating immune complexes, immunoglobulin G-containing circulating immune complexes, and endotoxin were measured in the sera of patients with obstructive jaundice. The bile of patients with percutaneous transhepatic biliary drainage was also cultured for bacteriologic studies. There was a significantly positive correlation between the endotoxin levels and both immunoglobulin A-containing circulating immune complex and immunoglobulin G-containing circulating immune complex. The endotoxin levels of the patients with gram-negative infections were significantly increased compared with those of the patients with sterile cultures. The immunoglobulin G-containing circulating immune complex levels of the patients with bacteria in bile were significantly increased compared with those of the patients with sterile cultures. The immunoglobulin A-containing circulating immune complex levels of the patients with bacteria in bile were slightly increased, but the difference did not reach statistical significance. These results indicate that one of the causes of increased circulating immune complex levels may be endotoxemia in combination with biliary infection in patients with biliary obstruction.

Renal impairment following biliary tract surgery

Postoperative mortality has been directly attributed to renal failure in approximately 5 per cent of patients after surgery for obstructive jaundice. An analysis of 334 patients undergoing biliary tract surgery was undertaken to identify the perioperative factors associated with the development of renal impairment, and to estimate the contribution of renal failure to mortality. Thirty-eight patients (11 per cent) developed postoperative renal impairment (a two-fold increase in serum creatinine postoperatively or a rise of greater than 100 mumol/l). Ninety-three factors were examined in these and 196 control patients. Stepwise logistic regression analysis identified only three factors which were significantly associated with renal impairment: postoperative sepsis (P less than 0.0005), pre-operative serum bilirubin (P less than 0.0005), and pre-operative urea (P less than 0.05). Renal impairment developed at a median 4 days after surgery and was associated with a median of two additional major postoperative complications, particularly sepsis and haemorrhage, for which 17 patients underwent reoperation. Twenty-eight (74 per cent) of the patients with renal impairment died in hospital, but in only one case was the cause of death directly related to renal failure. Twenty patients received specific therapy for renal failure, but only one of these survived. Pre-operative obstructive jaundice and postoperative infection are the major factors associated with renal impairment after biliary tract surgery. Renal impairment appears to be related to postoperative complications rather than directly to the surgical procedure itself. The development of postoperative renal impairment predicts a low chance of survival but appears to be an indicator, rather than a direct cause of a poor prognosis.

Surgery in the patient with liver disease

This article deals with the effects of anesthesia and surgery on the healthy and diseased liver and the preoperative assessment of patients with liver disease. Emphasis is placed on estimating surgical risk. Guidelines for optimal preoperative preparation are discussed.

Endotoxemia in patients with alcoholic and non-alcoholic cirrhosis and in subjects with no evidence of chronic liver disease following acute alcohol excess

The presence of endotoxemia in peripheral venous blood was evaluated in 88 patients with alcoholic cirrhosis (AC) and in 42 patients with non-alcoholic cirrhosis (NAC). The two groups did not differ significantly with respect to mean age, liver function tests, and incidence of esophageal varices or ascites. In addition, a group of 24 patients with no evidence of chronic liver disease but with acute exposure to large quantities of alcoholic beverages was investigated. Endotoxin was determined by using the Limulus lysate test. The assays were carried out in the plasma samples by both the dilution technique and the chloroform extraction method. Endotoxemia was found more frequently in patients with AC (67.3%) than in patients with NAC (45.5%, P less than 0.025). The prevalence of endotoxemia was not significantly higher in cirrhotics with ascites or esophageal varices when compared to the subgroup without ascites or esophageal varices. Of the 24 patients with no evidence of chronic liver disease investigated because of acute alcohol excess immediately before admission 11 (45.7%) were found to have endotoxin in the peripheral venous blood. In 7 of these patients a second blood sample was tested 5-8 days later and no endotoxin could be detected. The latter results suggest that heavy alcohol abuse leads to transient endotoxemia even in patients with no signs of chronic liver disease. The findings support the hypothesis that gut-derived endotoxins might play a role in the initiation and aggravation of alcohol-induced liver disease.

Antibody titres to a rough-mutant strain of Escherichia coli in patients undergoing allogeneic bone-marrow transplantation. Evidence of a protective effect against graft-versus-host disease

Much clinical and experimental evidence suggests that infection and graft-versus-host disease (GvHD) are commonly associated as complications of bone-marrow transplantation (BMT). A likely basis for this association is the gram-negative faecal flora,the origin of many septicaemias and a source of bacterial endotoxin, which has potent immunostimulatory effects. A rough-mutant strain, Escherichia coli J5, has only core determinants in its endotoxin,and antibodies to E coli J5 protect animals and human beings from the consequences of septic shock. Naturally occurring antibodies to E coli J5 ("anti-endotoxin") were assayed in serum from patients undergoing BMT, healthy controls, and patients with obstructive jaundice. BMT recipients had significantly lower titres than the other two groups. Furthermore, the titre of IgM class anti-J5 antibody was significantly associated with protection from GvHD.

Effects of bile acids and endotoxin on the function and morphology of cultured hamster Kupffer cells

The mechanisms of hepatic reticuloendothelial cell dysfunction in obstructive jaundice were investigated using cultured hamster Kupffer cells. The introduction of free bile acids, cholic acid (CA) at concentrations over 2 mM and chenodeoxycholic acid (CDCA) over 1 mM inhibited colloidal carbon pinocytosis. CA and CDCA at concentrations over 0.5 mM inhibited IgG-coated sheep red blood cell phagocytosis. With the application of conjugated bile acid and endotoxin at concentrations over 50 micrograms/ml, endocytic function was inhibited. With bile acids, a dose-dependent increase in the concentration of beta-glucuronidase occurred in the culture medium, and with endotoxin a time-dependent increase in beta-glucuronidase was noted. Bile acids produced alterations in cell organelles before destruction of the cell membrane. The presence of endotoxin led to the appearance of large vacuoles in the cytoplasm. These observations suggest that bile acids and endotoxin inhibit Kupffer cells by different mechanisms. We tentatively conclude that bile acids rather than endotoxin influence Kupffer cells in vivo.

A comparison of methods of removing inhibitors to the chromogenic Limulus assay in normal and jaundiced blood

A comparative study was performed of methods of removing inhibitors to the quantitative chromogenic method of Limulus assay for endotoxin in normal and jaundiced plasma. Chloroform treatment failed to remove inhibitors in normal and jaundiced plasma and did not prevent inhibition of colorimetry by bilirubin. Perchloracetic acid (PCA) treatment decolourised jaundiced samples but gave unreliable results due to poor pH control. Boiling and dilution gave reliable results in jaundiced and normal plasma without significant loss of sensitivity and is the method of choice.

A randomized clinical trial of oral ursodeoxycholic acid in obstructive jaundice

Forty patients with obstructive jaundice (bilirubin greater than 100 mumol/l) were entered into a randomized trial of oral ursodeoxycholic acid for 48 h before surgery versus no additional therapy. Pre-operative venous and operative portal total bile salt concentrations were higher in the bile salt treated patients (P less than 0.001). Portal endotoxaemia during operation was reduced in ursodeoxycholic acid treated patients (P less than 0.05). There was no significant difference in systemic venous endotoxaemia, renal function or postoperative morbidity or mortality. This study suggests pre-operative oral bile salt therapy may be of no clinical benefit in patients with obstructive jaundice.

The pathogenesis of renal sodium retention and ascites formation in Laennec's cirrhosis

This chapter critically reviews our current understanding of the pathogenesis, clinical syndrome, and therapy of the disturbances of renal sodium handling, renal perfusion, and glomerular filtration rate that occur in patients with Laennec's cirrhosis. Avid renal sodium reabsorption, a characteristic feature of cirrhosis, occurs independent of moderate changes in renal function and precedes the onset of ascites. The initiation of sodium retention may be a direct consequence of the hepatic disease process and may also result from defective intravascular filling. In the presence of ascites the most important sodium retaining signal is a defective intravascular volume. The principal effectors of renal sodium retention and vasoconstriction are stimulation of the renin-angiotensin-aldosterone axis and augmentation of renal sympathetic nerve activity. Deficient production of natriuretic hormone(s) and endogenous renal vasodilators, such as prostaglandins and kinins, also contributes to the sodium retention and renal hypoperfusion seen in cirrhosis. The hepatorenal syndrome is an extreme imbalance in these renal vasoconstrictor and vasodilator forces. In the therapy of ascites in Laennec's cirrhosis, abstention from alcohol, sodium restriction, and cautious diuresis are the principal therapeutic measures. A grave prognosis accompanies the diagnosis of the hepatorenal syndrome although recoveries have been reported.

Effects of nadolol treatment on renal and hepatic hemodynamics and function in cirrhotic patients with portal hypertension

Twelve cirrhotic patients with portal hypertension and esophageal varices were treated with nadolol for 1 month, and the effects on renal and hepatic hemodynamics and function were studied. A significant decrease in cardiac output, portohepatic gradient, and effective hepatic blood flow was found, whereas mean arterial pressure, liver function, effective renal blood flow, glomerular filtration rate, and urinary sodium and potassium excretions were not affected. In seven patients esophageal varices were also reduced. A significant correlation was found between the decrease in portohepatic gradient and that in cardiac output. The percentage of cardiac output distributed to the kidneys was significantly increased after nadolol treatment. In conclusion, nadolol seems to have properties useful for the treatment of portal hypertension in patients with liver cirrhosis.

Endotoxemia in human obstructive jaundice. Effect of polymyxin B

A clinical trial was undertaken to study endotoxemia in 14 patients with obstructive jaundice given the antiendotoxin polymyxin B, 13 patients with obstructive jaundice who were not given the antiendotoxin , and 13 nonjaundiced control patients undergoing comparable surgery. Endotoxins were detected by the limulus assay. Endotoxemia did not occur in the nonjaundiced patients but was common before (68 percent), during (70 percent), and after (81 percent) surgery in the jaundice patients. Thirty-six percent of the jaundiced patients had postoperative oliguria. Endotoxemia before surgery was associated with death after surgery, all deaths occurring in patients who were endotoxemic before operation (p less than 0.05). Polymyxin B infusion had no effect on endotoxemia or outcome. Measurement of indicators of fibrinolysis, soluble fibrin, and fibrin degradation products showed no prognostic significance. We conclude that preoperative endotoxemia is an important predictor of outcome in patients who undergo surgery for jaundice.

Upper gastrointestinal bleeding. A significant complication after surgery for relief of obstructive jaundice

A retrospective review of 409 patients with bile duct obstruction (373 undergoing definitive surgery and 36 undergoing laparotomy only) identified 27 patients who developed significant postoperative gastrointestinal bleeding necessitating transfusion. All 27 had undergone a definitive procedure to relieve obstruction. Nineteen patients required blood replacement of six or more units. The majority of patients bled in the first four postoperative days. The sites of hemorrhage were identified in 25 patients, gastric erosions being the most common lesions detected. Thirteen of the 27 patients died, seven due to overwhelming blood loss despite massive transfusion. Eight of the 27 required an operation because of bleeding. An analysis of the relationship between preoperative factors and gastrointestinal bleeding identified three factors that were independently associated with this complication. These were: 1) an initial hematocrit of 30% or less; 2) an initial leukocyte count in excess of 10 X 10(9)/l; and 3) a malignant obstructing lesion. Patients with two or all three of these factors were identified as being at very high risk of developing postoperative gastrointestinal hemorrhage. Bleeding into the upper gastrointestinal tract has been confirmed to be a major problem in the surgical management of patients with obstructive jaundice. Further studies of the etiology and prevention of this complication are indicated.

[Kidney involvement in liver diseases. Pathophysiology and clinical course]

Renal disorders complicating liver disease are a frequent finding. Extrahepatic causes like intoxications and circulatory dysfunction or diseases that simultaneously affect both the liver and the kidney, like multisystem or viral diseases (hepatitis B) have to be differentiated from clinical entities in which, like in liver cirrhosis or in fulminant hepatitis, the manifestation of renal disease has to be understood as a consequence of the hepatic disorders. Functional disturbances like the increases in tubular sodium reabsorption or the hepatorenal syndrome have been thoroughly investigate because of their clinical importance. Substantial research dealing with the consequences of the increased intrahepatic vascular resistance on systemic and renal hemodynamics and with vasoactive substances, either arising from the liver or accumulating due to poor inactivation by the liver, have led - in the last years - to a better understanding of the pathophysiology of renal involvement in liver disease. However, the exact pathophysiologic role of factors like the effective blood volume, the sympathoadrenergic tonus, the activation of the renin-angiotensin-aldosterone system, changes of kinin activity or in prostaglandin release and the accumulation of "false" neurotransmitters and endotoxins still remains to be established.

Prevention of postoperative renal failure in patients with obstructive jaundice--the role of bile salts

Preoperative administration of the simple bile salt sodium deoxycholate has been shown in this study to prevent postoperative endotoxaemia and renal failure in patients with obstructive jaundice. Fifty-four per cent of jaundiced patients not given the salt were found to have systemic endotoxaemia, associated with renal impairment in two-thirds of the cases. No patient given sodium deoxycholate 500 mg 8 hourly for 48 hours before operation had portal or systemic endotoxaemia, and none had evidence of renal impairment (P less than 0 X 02, X2 with Yates' correction). The incidence of endotoxaemia in untreated jaundiced patients was very significantly greater than in non-jaundiced patients undergoing elective upper abdominal surgery (P less than 0 X 005), but this difference is abolished by the prophylactic administration of the oral bile salt. The mechanism of action of bile salts in preventing endotoxin absorption from the small bowel has been investigated, and the lack of any significant alteration in the small bowel microbial flora in obstructive jaundice suggests that a direct effect on the endotoxin molecule is involved. Nearly 20 per cent of patients with obstructive jaundice still develop postoperative renal insufficiency, but preoperative prophylactic use of sodium deoxycholate should reduce this very significantly.

Endotoxaemia in septic shock: clinical and post mortem correlations

The Limulus amoebocyte lysate assay was used as one of a series of laboratory and clinical investigations on a group of 31 patients suffering from septic shock in order to assess the clinical significance of this assay for the detection of circulating endotoxin in clinical gram-negative sepsis. Four patients with cardiogenic shock served as controls. Endotoxin was detected in the bloodstream of all patients with septic shock during the 24 h following referral and was not detected in the control patients. Eventual clinical recovery was associated with the disappearance of endotoxin from the peripheral blood. Blood cultures were unhelpful as a prognostic indicator in these critically ill patients. A quantitative assay of endotoxin in blood may allow a more precise relationship with the clinical manifestations of major sepsis.

Raised plasma thromboxane B2 levels in alcoholic liver disease

In experimental animals endotoxin administration causes increased levels of thromboxane B2 and prostaglandins. Liver cirrhosis is often complicated by endotoxemia. In sixteen patients with alcoholic liver cirrhosis, we measured plasma thromboxane B2 levels. In twelve patients we found on one or more occasions raised plasma thromboxane B2 levels. Raised plasma thromboxane B2 levels were associated with significantly higher serum levels of urea, alkaline phosphatase, gamma glutamyl transpeptidase and lower antiplasmin and antithrombin III levels. It is possible that some of the complications in patients with alcoholic liver cirrhosis are mediated by thromboxanes.

Enteric coated polymyxin B in the treatment of hyperammonemia and endotoxemia in liver cirrhosis

Effects of enteric coated polymyxin B capsules on hyperammonemia and endotoxemia in liver cirrhosis were investigated. Six million units of polymyxin B were orally administered daily to 21 patients with liver cirrhosis and 3 patients with hepatoma cum liver cirrhosis, whose plasma ammonia was higher than normal limit and/or whose plasma endotoxin was positive, for 5-32 days, and serum polymyxin B concentration (in 5 cases), changes of plasma ammonia level (in 19 cases) and plasma endotoxin (in all cases) were observed. Serum polymyxin B concentration was below the detectable limit (0.5 unit/ml) in all cases observed. In the patients with liver cirrhosis, plasma endotoxin and ammonia levels decreased rapidly after polymyxin B treatment, and the decreases in endotoxin levels were kept throughout the treatment. Twelve patients with liver cirrhosis (10 among them were treated with lactulose) were served as controls. All patients who were treated with lactulose alone showed rapid decrease in plasma ammonia, but the decrease in endotoxin in these patients was slower than that in those treated with polymyxin B. From these results, oral administration of polymyxin B is concluded to be useful in the treatment of hyperammonemia and endotoxemia in liver cirrhosis, as a poorly absorbed antibiotic and as an antiendotoxin agent.

The effect of preoperative bile salt administration on postoperative renal function in patients with obstructive jaundice

We have studied the effect of the preoperative administration of bile salts on postoperative renal function in jaundiced patients undergoing surgery. Nine patients did not receive bile salts and in this group there were 2 cases of acute renal failure in the postoperative period. Furthermore, creatinine clearance values fell in this group from a mean value of 85 ml/min preoperatively to a mean postoperative value of 55 ml/min. Nine patients received preoperative bile salts with no case of renal failure. Creatinine clearance values increased in all but 2 patients from a mean preoperative value for the group 79 ml/min to a mean postoperative value for the group of 99 ml/min. The difference between the changes in creatinine clearance in the two groups was statistically significant (P less than 0.01). The results of this study suggest that the oral administration of bile salts to jaundiced patients in the preoperative period prevents deterioration in renal function postoperatively and also reduces the incidence of postoperative renal failure.

Preoperative external biliary drainage in obstructive jaundice. A prospective controlled clinical trial

57 patients with obstructive jaundice were randomly allocated to surgery with preoperative external biliary drainage (29 patients) and without preoperative external biliary drainage (28 patients). 22 patients ultimately underwent laparotomy after a mean of 11.7 days of drainage and 25 had surgery without preoperative drainage. The postoperative complication rate was low and similar in both groups but complications associated with the drainage procedure were substantial. Perioperative mortality was 4/28 (14%) in the drainage group and 4/27 (15%) in the non-drainage group. There seems to be no advantage associated with routine preoperative external biliary drainage before surgery for obstructive jaundice.

Lack of correlation between endotoxaemia and renal hypoperfusion in cirrhotics without overt renal failure

Renal involvement in patients with liver cirrhosis is characterized by renal vasoconstriction, the aetiology of which remains obscure. Endotoxaemia, frequently found in patients with liver cirrhosis and renal failure, has been emphasized as a pathogenic factor. In fifty-seven patients with liver cirrhosis without overt renal failure endotoxin plasma level (Limulus Lysate test), mean renal blood flow (MRBF) (133Xe washout technique), and effective renal plasma flow (ERPF) (p-aminohippurate clearance) were determined. MRBF was decreased in nineteen out of twenty-seven patients, averaging 1.88 +/- 0.51 ml g-1 min-1 (in fourteen controls 3.17 +/- 0.51 ml g-1 ml-1). ERPF was decreased in seventeen out of thirty patients, averaging 380 +/- 164 ml/min (in eighteen controls 624 +/- 127 ml/min). Systemic endotoxaemia was found in sixteen out of fifty-seven patients, levels ranging from 0.62 to 200 ng/ml. No significant difference in renal blood flow values was found between patients with and without endotoxaemia (MRBF = 1.78 +/- 0.51 and 1.93 +/- 0.52 ml g-1 min-1 respectively; ERPF = 429 +/- 119 and 365 +/- 175 ml/min respectively). No significant difference in the frequency of endotoxaemia was found between patients with impaired and unimpaired renal blood flow. Moreover no relation was found between endotoxin plasma levels and MRBF and ERPF respectively. In conclusion in patients with cirrhosis without overt renal failure renal vasoconstriction does not seem to be related to endotoxaemia.

Endotoxin, prostaglandins and renal fibrin deposition in obstructive jaundice

The delayed clearance of endotoxins in obstructive jaundice may cause renal impairment by inducing renal vasoconstriction and glomerular fibrin deposition as a consequence of intravascular coagulation. As endotoxins activate arachidonic acid metabolism we have examined the effects of selective inhibitors on mortality, plasma TXB2 and 6-oxo-PGF1 alpha production and renal fibrin deposition in rats with obstructive jaundice following endotoxin administration. Jaundiced rats had a high mortality following endotoxin--58 per cent at 4 h and 83 per cent at 24 h. Pretreatment with indomethacin 3 mg/kg i.p., dazoxiben 3 mg i.p. or prostacyclin 300 ng/kg i.v. produced significant improvements in survival. Endotoxaemia was associated with significant elevations of plasma TXB2 and early inhibition of plasma 6-oxo-PGF1 alpha generation. Renal fibrin deposition, assessed using indirect immunofluorescence and a 125I-labelled fibrinogen uptake ratio, occurred in jaundiced kidneys following endotoxin and could be prevented using indomethacin, dazoxiben and prostacylin. These results suggest that endotoxin-induced TXA2 production can cause renal fibrin deposition in obstructive jaundice, thus contributing in the pathogenesis of the renal impairment.

Endotoxemia, disturbance of coagulation, and obstructive jaundice

A prospective study of coagulation disturbances and endotoxemia in 42 patients having major pancreatic or biliary surgery was performed. Endotoxin, soluble fibrin, and fibrin degradation products were measured before and after operation in 28 patients with obstructive jaundice and in 14 nonjaundiced controls. In the control group there was one death and no unexplained fever or postoperative hemorrhage. The jaundiced group had more complications: seven deaths, nine episodes of fever, and six episodes of hemorrhage. Soluble fibrin was detected only in patients with obstructive jaundice, in whom it occurred in 38 percent before operation. Positive endotoxin assay was as common in control patients as in the jaundiced group, but in the latter endotoxin was associated (p less than 0.05) with increased FDP and soluble fibrin. Patients with endotoxin or increased FDP levels before operation for jaundice carry a poor prognosis (7 of 11 died). Preoperative bowel preparation in 16 of the jaundiced patients did not affect the outcome.