Association of endotoxaemia & gut permeability with complications of acute pancreatitis: Secondary analysis of data.

Background & objectives: In acute pancreatitis (AP) gut barrier dysfunction is considered as an important predisposing factor leading to increased intestinal permeability (IP). In this study a pooled analysis of data published in our previous four studies on various aspects of gut permeability and endotoxaemia in patients with AP was attempted to find an association between increased IP and severity of disease and associated complications. Methods: This study was a pooled analysis of data of four previously published prospective studies on AP. Gut permeability, assessed by lactulose/mannitol excretion in urine and endotoxin core antibodies type IgG and IgM (EndoCab IgG and IgM) were measured on days zero and seven (D0 and D7) of admission. All patients received standard treatment of AP. We studied whether IgG and IgM anti-endotoxin titres and lactulose-mannitol ratio (LMR) at admission and D7 were associated with organ failure, infection and mortality. Results: The titres of anti-endotoxin IgG and IgM were lower in all patients of AP (n=204), both in mild AP (n=24) and severe AP (n=180) in the first week, compared to controls (n=15). There was no significant difference in serum IgG and IgM anti-endotoxin levels and LMR at baseline and at D7 among patients with organ failure, infection and mortality. Interpretation & conclusions: Our findings showed that serum IgG and IgM anti-endotoxin titres and LMR at admission and at day 7 were not associated with organ failure, infection, and death of patients with AP.

Effect over time of endotoxin adsorption therapy in sepsis.

Despite the use of potent antibiotics and intensive supportive care, the mortality among patients with sepsis and Gram-negative bacteremia remains high. In recent years, endotoxin adsorption therapy (PMX-DHP, polymyxin-direct hemoperfusion) has been widely used in Japan to remove endotoxin, a causative agent of sepsis. In septic patients whose clinical condition may change at any moment, the decision of when to perform blood purification in addition to conventional intensive care is a critical factor in the therapeutic strategy and prognosis. In the present study, we investigated the effect over time of PMX-DHP in sepsis. The subjects were 16 patients with systemic inflammatory response syndrome (SIRS) who required surgical treatment including a surgical operation and drainage. The following six parameters were compared between the first and second PMX-DHP: mean blood pressure and time-restricted urine at four time points - at baseline and at 6, 24 and 72 h after PMX-DHP; and white blood cell count, platelet count, base excess and Septic Severity Score (SSS) at 24 and 72 h after PMX-DHP. Mean blood pressure improved over time up to 24 h after both the first and second PMX-DHP. Time-restricted urine volume improved only at 6 h after the first PMX-DHP. White blood cell count improved over time up to 24 h after both the first and second PMX-DHP. The SSS improved at all time points studied except for 3 days after the second PMX-DHP. We conclude that PMX-DHP is expected to have important implications in terms of (i) correction of clinical conditions (by severity assessment); (ii) improvement of hemodynamics; (iii) possible anti-inflammatory effect; and (iv) possible improvement of oxygen metabolism in tissues.

Mode of action of human urinary colony-stimulating factor.

Human urinary colony-stimulating factor (CSF-HU) has been highly purified using procedures containing DEAE cellulose, phenyl Sepharose CL-4B, Sephadex G-200, hydroxylapatite, and high performance liquid chromatography. The final preparation had a specific activity of 3.3 X 10(7) U/mg protein. Although the purified CSF-HU was not active on human monocyte-depleted bone marrow cells, it stimulated human peripheral blood monocytes obtained from five healthy volunteers to produce human active granulocytic colony-stimulating factor (G-CSF), which stimulated human monocyte-depleted bone marrow cells to form granulocytic colonies. The human G-CSF-producing activity of CSF-HU was not neutralized by polymyxin B, which is known to inhibit the effect of endotoxin. Newly produced G-CSF had an approximate molecular weight of 24,000 daltons as judged by chromatography on Sephadex G-150. These results indicate that CSF-HU stimulates human monocytes to produce human G-CSF in vitro.

Comparative evaluation of the Limulus assay and the direct Gram stain for detection of significant bacteriuria.

A double-blind study comparing the Limulus in-vitro endotoxin assay with the direct Gram stain of uncentrifuged urine for detection of significant bacteriuria was performed. One-thousand seventy-seven urine specimens were examined by the two methods and the results compared with results of quantitative urine cultures. Two hundred three samples produced growth of greater than 10-5 organisms per ml. urine. The Limulus assay detected 86.2% of these specimens, and 98.8% of urines that contained greater than 10-5 Gram-negative bacilli per ml. The Gram stain procedure detected only 69.5% of urines containing greater than 10-5 organisms per ml. and 74.5% of specimens with greater than 10-5 Gram-negative bacteria per ml. urine. The Limulus assay demonstrated both greater sensitivity and greater specificity than the Gram stain procedure. Moreover, the Limulus test is much less susceptible to errors of interpretation than methods involving microscopy.

Effect of bacterial products including endotoxin on neutrophil function in infected urine.

Experiments were performed to determine the effects of products of bacterial growth (including endotoxin) on phagocytosis and intracellular killing by polymorphonuclear leucocytes (PMNL) in urine. Bacteriologically filtered supernates of two strains of Escherichia coli grown in urine were added in varying amounts to mixtures of PMNL and E. coli, also in urine. Phagocytosis of the two strains was reduced from > 90% in controls to 66% and 48%, respectively, in the presence of undiluted culture filtrate (containing endotoxin 2-2.5 micrograms/ml). Intracellular killing was also decreased and was abolished by dilutions corresponding to endotoxin concentrations of 0.6 and 0.75 micrograms/ml. When PMNL exposed to these inhibitory dilutions were resuspended in fresh urine, their phagocytic ability was fully restored and 13-24% of their killing activity was regained. A minimum concentration of commercially purified E. coli endotoxin of 200 micrograms/ml was required to abolished PMNL killing, with phagocytosis uninhibited. The results strongly suggest that bacterial growth metabolites, not endotoxin, are responsible for the depression of phagocytosis and intracellular killing in infected urine. A moderate dilution of the bacterial products in urine permits good PMNL function. Extrapolating this to the clinical situation, diluting the urine by water loading (as recommended for patients with urinary infections) should ensure efficient activity of PMNL under in-vivo conditions providing urinary pH and osmolality are not adversely affected.

Known bacterial virulence factors do not explain the variation in urinary cytokine levels in patients with urosepsis.

We measured urinary endotoxin, IL-6 and IL-8 levels in 23 patients with gram-negative urosepsis. The endotoxin and cytokine levels showed a 100-1000 fold range. No correlation was found between levels of urinary endotoxin, and IL-6 or IL-8 levels. In all cases bacterial numbers were > or = 10(5) CFU ml-1 urine. The endotoxin content of the isolated microorganisms neither correlated with the urinary cytokine levels, nor with IL-6 and IL-8 levels obtained in vitro when 10(3) log-phase CFU of each of the bacteria were incubated with heparinized whole blood of three healthy donors. Neither the haemolysin phenotype of the bacteria, nor the presence of the P-pili gene was correlated with the cytokine response in vivo or in vitro. Other factors than known bacterial virulence factors apparently contribute to the wide variation in urinary cytokine levels in urinary tract infection.

Evaluation of endotoxiuria for diagnosis of urinary tract infection after major surgical procedures.

In 148 patients after major surgical procedures urinary endotoxin levels were determined and compared with bacteriological results. The study was designed as a screening study. Urine samples were collected once by suprapubic or transurethral catheters. In a first series of 49 patients urine bacteriology was positive (mainly, Gram-negative rods were found) in 3 cases. However, endotoxin determination was positive in these 3 patients and in a further 10 patients receiving antibiotic therapy for other reasons. Therefore, the following 99 patients were studied also by urinalysis by reagent strips for leukocytes and nitrite. In the second series, 12 urine cultures positive for bacteria were observed. Eleven samples were also endotoxin positive. Five more patients were endotoxin positive and had pathological but unspecific reagent strip results. These patients were treated with antibiotics for other reasons. Patients with candida found in the urine culture (n = 5) were endotoxin negative. Thus, endotoxin determination in urine obtained by suprapubic or transurethral catheters proved to be a very sensitive method for diagnosis of bacterial contamination, even during antibiotic treatment.

Elimination of Proteus mirabilis 51Cr endotoxin from the liver in rats.

Using isotope methods, elimination of the endotoxin of Proteus mirabilis labeled with chromium (CrEPm) from the liver of rats was studied. The following studies were carried out: intravital exploration of the liver with a scintillation probe, measurements of radioactivity of organs and excreted urine and stools, scrintigraphy of the liver, binding of CrEPm by subcellular fractions of hepatocytes, and the influence of selected drugs (polymyxin and hydrocortisone) on elimination of CrEPm from the liver and organelles of hepatocytes.

Investigation of infection risk and the value of urine endotoxin during extracorporeal shock wave lithotripsy.

OBJECTIVE: To clarify the infection risks and the value of endotoxin determination in urine during extracorporeal shock wave lithotripsy (ESWL). METHODS: According to the distribution and complications of upper urinary calculi, 164 patients were divided into five groups. Group A consisted of 48 patients with 1 to 4 renal calculi, which were or less than 2 cm in diameter. Group B was composed of 24 patients with renal calculus larger than 2 cm in diameter or one to multiple renal calculi. Group C was composed of 22 patients with 1 to 3 renal calculi accompanied by 1 to 2 ureteric calculi. Group D consisted of 51 patients with 1 to 3 ureteric calculi that were 0.5 to 1.2 cm in diameter, respectively. Group E included 19 patients with complicated renal calculus, such as casting and staghorn renal calculus. Urine and blood samples of these patients were obtained before and after ESWL, respectively. Their urine samples were proven sterile prior to treatment. All samples were cultured for bacteria and investigated for endotoxin concentration by the limulus lysate test. RESULTS: No significant difference in serum endotoxin was noted before and after ESWL. Blood bacterial cultures were all negative in all patients after ESWL, similar to those before ESWL. Significant increases in urine endotoxin after ESWL compared with that before ESWL in patients of Groups B, C and E were observed, respectively (P < 0.05). There was no significant difference in urine endotoxin after ESWL compared with that before ESWL in patients of Groups A and D. The positive incidences of urine bacterial culture were significantly increased (P < 0.05) in Groups B and C and very significantly increased (P < 0.01) in Group E compared with those in Groups A and D. CONCLUSIONS: Urinary infection risk following ESWL was lower in patients with one to several renal calculi, which were less than 2 cm in diameter and did not interfere obviously with the urine flow or in patients with 1 to 3 ureteric calculi that were 0.5 to 1.2 cm in diameter. The risk was higher in those with complicated calculi, such as casting, staghorn renal calculus, renal calculus larger than 2 cm in diameter or renal calculi accompanied by ureteric calculi. For patients with higher infection risk after ESWL, prophylactic antibiotics are necessary even if bacteriuria is not present before ESWL. Endotoxin determination in urine is a reliable, sensitive and simple method for the diagnosis of bacterial infection in patients undergoing ESWL.

[Rapid diagnosis of gram-negative bacteriuria with endotoxin-specific chromogenic test].

Limulus amebocyte lysate test is a simple, yet sensitive laboratory method for detecting endotoxin. Although the specificity of the test was questioned, we recently solved this problem by removing a (1----3)-beta-D-glucan-sensitive factor G from the lysate (Endospecy, Seikagaku Kogyo Co., Ltd, Tokyo). In this study, we have established a method for the determination of endotoxin urine in using Endospecy. An aliquot of 0.2 ml of Endospecy dissolved in 4.4 ml of 0.1 mol/l Tris-HCl buffer (pH 8.0) was added to 5 microliter of urine sample. The mixture was incubated at 37 degrees C for 30 min. After diazo-coupling, absorbance was measured at 545 nm. The standard curve using Escherichia coli 0111: B4 endotoxin showed a good linearity. The addition-recovery test of various endotoxins showed nearly 100% recovery. Normal urine contained less than 60 pg/ml of endotoxin. Urine from patients with Gram-negative bacteriuria showed definitely high values, whereas urines infected either with Gram-positive bacteria or with fungi all showed nearly normal values. This method will be useful as a rapid and reliable test for the diagnosis of urinary tract infection with Gram-negative bacteria.

[Investigation of infection risk and the value of antibiotic prophylaxis during transrectal biopsy of the prostate by endotoxin determination].

OBJECTIVE: To clarify the value of endotoxin determination in evaluating the infection risk and antibiotic prophylaxis during transrectal biopsy of the prostate. METHODS: Forty-eight patients were divided into four groups randomly. Group A (12 patients) were not treated before biopsy. Group B (13 patients) received antibiotic prophylaxis therapy. Group C (12 patients) underwent clusis. Group D (11 patients) received combined treatment. Urine and blood samples of the patients were obtained before and after prostatic biopsy. All samples were cultured for bacteria and investigated for endotoxin concentration by limulus quantitative azo color test. RESULTS: No significant difference in either serum endotoxin or blood bacterial cultures was noted before and after prostatic biopsy (P < 0.05) in all the groups. A significant increase was observed in urine endotoxin after biopsy compared with that before biopsy in Groups A and B (P < 0.05). There was no significant increase in urine endotoxin after biopsy compared with that before biopsy in Group C and D. The positive incidence of urine bacterial culture was significantly increased (P < 0.05) in patients of Group A and B. CONCLUSION: Circulation infection risk following prostatic biopsy was low. Changes of urinary infection were fewer in patients who had undergone clusis and/or antibiotic prophylaxis than in those who had received no or only antibiotic prophylaxis therapy. Endotoxin determination in urine is a reliable, sensitive and simple method for diagnosis of bacterial infection in patients undergoing transrectal biopsy of the prostate.

[Endotoxicosis in severe multiple trauma]. / Endotoksikoz pri tiazheloí sochetannoí travme.

The article touches upon the practical significance of methods of extracorporeal detoxication, pathogenesis of endotoxicosis, phases of its development. An analysis of data was made concerning treatment of 98 wounded and patients having injuries of three and more anatomical areas and who were in severe and critically severe states. Practical conclusions were made determining the expediency of using the methods of extracoprporeal detoxication in traumatic disease, special attention being given to optimization of functioning the detoxicating systems of organism.

Usefulness of LAL assay for rapid detection of gram-negative bacteriuria.

LAL assay is a rapid and reliable and easy to perform and interpret urine screen for clinically significant gram-negative bacteriuria. Chromogenic assays are rapid (5 min) and obviate problems associated with gel endpoints, such as inadvertant dissolution of the gel, either during incubation or reading. LAL urine screening is characterized by both high positive and negative predictive values. LAL urine assay identifies gram-negative urinary tract infections by measuring urine endotoxin content as an index for significant numbers of urinary tract pathogens, thus eliminating large numbers of false-positive tests characteristic of other urine screening methods. Screening urine for greater than or equal to 10(5) CFU/ml appears to be an acceptable criterion for defining a UTI in patient populations with low prevalence rates (2-10%). Thus, LAL urine assay may have potential usefulness for screening of asymptomatic populations, such as pregnant women and the elderly.

Detection of endotoxiuria in polycystic kidney disease patients by the use of the Limulus amebocyte lysate assay.

Urinary tract infections (UTI) due to gram-negative bacteria are a serious complication in patients with polycystic kidney disease (PKD). Endotoxin, a component of the cell wall of gram-negative bacteria, has been reported to be pro-cystogenic in experimental animals. Because endotoxin levels in urines (endotoxiuria) from PKD patients have not been reported, the Limulus amebocyte lysate (LAL) assay, which detects picogram quantities of endotoxin, was used to probe for this cyst-promoting chemical. Fifteen PKD patients (seven females, eight males), asymptomatic for UTI, were tested and compared with 10 female and 10 male controls. All urines were assessed for (1) evidence of aerobic bacteria by routine quantitative cultures, (2) bacteria and pyuria by microscopic examination of gram-stained urine, and (3) bacterial endotoxin by the LAL assay. LAL tests were positive in 73% (11/15) of PKD patients, but only 25% (5/20) of controls (P = 0.0058). There was no significant difference in test positivity between PKD females (71%) and males (75%). There was no correlation of age, degree of renal dysfunction, or urine osmolality with endotoxiuria. Routine quantitative cultures were negative for gram-negative bacteria in PKD patients and all controls (except one female), as were microscopic findings for intact bacteria and pyuria. Thus endotoxiuria, in the absence of classical signs, symptoms, and microbiological findings of UTI, raises the possibility that endotoxin is available intrarenally to promote cystogenesis even before a potential susceptibility of PKD patients to classical UTI is manifested. Sources of urinary endotoxin observed in PKD patients, such as cryptic intrarenal sites or leakage from the gastrointestinal (GI) tract, remain to be defined.

Significance of urinary endotoxin concentration in patients with urinary tract infection.

Endotoxin is a component of the outer membrane of gram-negative rods (GNR). Since GNR are responsible for the majority of urinary tract infection (UTI), we measured the concentration of endotoxin in urine using chromogenic endotoxin-specific assay and examined its diagnostic utility in patients with suspected UTI. In all 18 urine samples with an endotoxin concentration exceeding 350 pg/ml and 2 samples with 10-350 pg/ml of endotoxin concentration, GNR were detected at a count of 10(4) cfu/ml. Negative for endotoxin were 3 samples of culture positive for gram-positive cocci (GPC), 2 samples containing various bacterial contaminants and all 37 samples with no growth on culture. Two urine samples collected 5 h after antibiotic dosage showed negative culture for GNR but a significant concentration of endotoxin. In an in vitro experiment, a residual concentration of antibiotic in urine inhibited bacterial growth, leading to a false-negative culture. These results suggest that chromogenic endotoxin assay is a reliable method for diagnosing UTI caused by GNR and detecting false-negative culture of GNR.

Urinary endotoxin excretion and urinary tract infection following kidney transplantation.

Following kidney transplantation, urine endotoxin levels were measured among 44 patients and compared to bacterial cultures. Urine samples were collected either via transurethral catheters or - after removal of the catheter on postoperative day 4 - by midstream void. In a control group of ten healthy volunteers, urine endotoxin levels were measured daily for 10 days. Urinary endotoxin concentration was measured by means of a chromogenically modified Limulus amebocyte lysate (LAL) test. The levels among patients with positive bacteriological findings (n = 21) were always elevated ( > 0.7 EU/ml). Furthermore, there was a marked, statistically significant difference in endotoxin values between samples with bacterial growth and samples with fungal or without any growth (P < 0.001). All 21 of the 44 patients with urinary tract infection (UTI) were endotoxin-positive. Seven more patients who received antibiotics had elevated urinary endotoxin levels, but no bacterial growth in the urine culture. No bacterial infection or significant urinary endotoxin was found in the control group. In summary, the detection of urinary endotoxin in samples obtained by either suprapubic/transurethral catheters or midstream void is an early, sensitive, and specific means of diagnosis that can be carried out even during antibiotic treatment.

Endotoxemia and hyperbilirubinemia in the neonate.

One hundred twenty-five neonates with varying serum bilirubin levels were tested for endotoxin by the limulus amebocyte lysate (LAL) test. Neither infection nor hemolytic disease was a contributing factor to the bilirubin levels. As the serum bilirubin level rose, positive LAL tests increased in frequency until the LAL test attained 100% at a level of 13 mg/dL. Bilirubin at different concentrations did not elicit positive LAL tests in plasma or normal saline in vitro. The LAL test was positive in urine obtained by suprapubic aspiration in 50% of neonates with positive serum LAL tests. Although bilirubin and endotoxin are cleared independently by hepatic cells with different functions, a striking relationship is evident between the endotoxin and bilirubin levels in the neonate. Immaturity of physiological liver functions in the neonate plays an important role. The LAL test cannot be used as an indicator of Gram-negative sepsis in neonates with unconjugated hyperbilirubinemia.

Studies with radioactive endotoxin. I. Clearance of 51Cr-labelled endotoxin from the blood of calves.

The clearance of (51)Cr-labelled Pseudomonas endotoxin from the blood was studied in calves in a nontolerant and in an endotoxin-tolerant state. Calves were rendered tolerant to the toxic effects of the endotoxin by four daily intravenous injections of endotoxin at the dose rate of 5 microg/kg body weight. Clearance of a small amount of (51)Cr-endotoxin from the blood of nontolerant calves was almost complete within three minutes of injection and was not significantly faster in tolerant calves. The lungs and liver were the major organs involved in clearance of endotoxin from the blood. The (51)Cr label was slowly excreted by the kidneys. Neither platelets nor leukocytes were demonstrated to participate in endotoxin clearance in calves. (51)CrCl(3) was injected into control calves. Relative to the distribution and loss of labelled endotoxin, the (51)CrCl(3) was cleared slowly from the blood, was distributed uniformly throughout the body and was excreted rapidly.

Rapid detection of gram-negative bacteriuria by use of the Limulus endotoxin assay.

The Limulus in vitro endotoxin assay was evaluated as a possible method for the prompt detection of significant gram-negative bacteriuria in children. This assay is capable of detecting endotoxin associated with intact cell walls of viable gram-negative bacteria as well as free endotoxin. Quantitative results are obtained following a 1-h incubation of Limulus lysate and 10-fold dilutions of otherwise untreated urine. A standard curve of Limulus activity and viable cell counts of Escherichia coli and Klebsiella pneumoniae in urine demonstrated that a positive Limulus reaction at a dilution of 1:100 or 1:1,000 indicated a colony count of at least 100,000 bacteria/ml. A positive Limulus reaction only from undiluted urine or at a dilution of 1:10 indicated less than 100,000 cells/ml. These experimental observations were confirmed by comparing the Limulus test with quantitative plate counts on 209 urine specimens from a mixed pediatric population. These results indicate that the Limulus assay is a simple, accurate method for rapid presumptive detection of gram-negative bacteriuria in patients where an immediate diagnosis is needed. This test would also seem promising for screening large patient populations for bacteriuria or for monitoring the effectiveness of treatment of urinary tract infections.