Clinical and microbiological effects of dialyzers reuse in hemodialysis patients / Efeitos clínicos e microbiológicos do reúso de dialisadores em pacientes em hemodiálise

Abstract Introduction: Chronic kidney disease (CKD) has a high prevalence and is a worldwide public health problem. Reuse of dialyzers is a cost reduction strategy used in many countries. There is controversy over its effects on clinical parameters and microbiological safety. Methods: In this clinical crossover study, 10 patients performed consecutive hemodialysis (HD) sessions divided in two phases: "single use" sessions (N = 10 HD sessions) followed by "dialyzer reuse" sessions (N = 30 HD sessions). Clinical, laboratory, and microbiological parameters were collected in the following time points: "single use", 1st, 6th, and 12th sessions with reuse of dialyzers, including bacterial cultures, endotoxins quantification in serum and dialyzer blood chamber, and detection of hemoglobin and protein residues in dialyzers. Results: Mean age of the sample was 37 ± 16 years, 6 (60%) were men, and 5 (50%) were white. CKD and HD vintage were 169 ± 108 and 47 (23-111) months, respectively. Serum C-reactive protein (CRP) [4.9 (2.1) mg/mL], ferritin (454 ± 223 ng/mL), and endotoxin levels [0.76 (0.61-0.91) EU/mL] were high at baseline. Comparison of pre- and post-HD variations of serum levels of CRP and endotoxins in the "single use" versus "reuse" phases did not result in differences (p = 0.8 and 0.4, respectively). Samples of liquid in the dialyzer inner chamber were negative for the growth of bacteria or endotoxins. There was no significant clinical manifestation within and between the phases. Conclusion: Dialyzers reuse was safe from a clinical, microbiological, and inflammatory point of view. The dialyzer performance remained adequate until the 12th reuse.

Resumo Introdução: A doença renal crônica (DRC) é um problema de saúde pública mundial de alta prevalência. O reúso de dialisadores é uma estratégia de redução de custos empregada em muitos países. Seus efeitos sobre parâmetros clínicos e de segurança microbiológica são alvo de controvérsia. Métodos: No presente estudo clínico cruzado, 10 pacientes realizaram sessões consecutivas de hemodiálise (HD) divididas em duas fases: a primeira com sessões de "uso único" (N = 10 sessões de HD) e a segunda com sessões com "reúso de dialisadores" (N = 30 sessões de HD). Parâmetros clínicos, laboratoriais e microbiológicos foram registrados nos seguintes momentos: "uso único", 1a, 6a e 12a sessões com reúso de dialisadores, incluindo culturas bacterianas, quantificação de endotoxinas no soro e na câmara interna do dialisador e detecção de hemoglobina e resíduos de proteína nos dialisadores. Resultados: A idade média da amostra foi de 37 ± 16 anos seis (60%) eram homens e cinco (50%) eram brancos. Os tempos com DRC e em HD foram de 169 ± 108 e 47 (23-111) meses, respectivamente. Os níveis séricos de proteína C-reativa (PCR) [4,9 (2,1) mg/mL], ferritina (454 ± 223 ng/mL) e endotoxinas [0,76 (0,61-0,91) UE/mL] estavam elevados no início do estudo. A diferença dos níveis séricos de PCR e endotoxinas pré e pós-HD nas fases de "uso único" e "reúso" não foi significativa (p = 0,8 e 0,4, respectivamente). As amostras de líquido retiradas da câmara interna do dialisador foram negativas para crescimento de bactérias e endotoxinas. Não houve registro de manifestações clínicas significativas nas fases do estudo. Conclusão: O reúso de dialisadores foi seguro dos pontos de vista clínico, microbiológico e inflamatório. O desempenho do dialisador permaneceu adequado até o 12º reuso.

Role of high mobility group box-1 and protection of growth hormone and somatostatin in severe acute pancreatitis

In this study, we investigated the potential role of high-mobility group box 1 (HMGB1) in severe acute pancreatitis (SAP) and the effects of growth hormone (G) and somatostatin (S) in SAP rats. The rats were randomly divided into 6 groups of 20 each: sham-operated, SAP, SAP+saline, SAP+G, SAP+S and SAP+G+S. Ileum and pancreas tissues of rats in each group were evaluated histologically. HMGB1 mRNA expression was measured by reverse transcription-PCR. Levels of circulating TNF-α, IL-1, IL-6, and endotoxin were also measured. In the SAP group, interstitial congestion and edema, inflammatory cell infiltration, and interstitial hemorrhage occurred in ileum and pancreas tissues. The levels of HMGB1, TNF-α, IL-1, IL-6 and endotoxin were significantly up-regulated in the SAP group compared with those in the sham-operated group, and the 7-day survival rate was 0%. In the SAP+G and SAP+S groups, the inflammatory response of the morphological structures was alleviated, the levels of HMGB1, TNF-α, IL-1, IL-6, and endotoxin were significantly decreased compared with those in the SAP group, and the survival rate was increased. Moreover, in the SAP+G+S group, all histological scores were significantly improved and the survival rate was significantly higher compared with the SAP group. In conclusion, HMGB1 might participate in pancreas and ileum injury in SAP. Growth hormone and somatostatin might play a therapeutic role in the inflammatory response of SAP.

Usefulness of the Endotoxin Activity Assay to Evaluate the Degree of Lung Injury

PURPOSE: It has been reported that the Pulse Contour Cardiac Output (PiCCO) is very useful mainly in the field of intensive care and treatment to grasp the pathophysiological conditions of pulmonary edema because of its capability of obtaining data such as Pulmonary Vascular Permeability Index (PVPI) and Extra Vascular Lung Water (EVLW). Furthermore, a high degree of usability of various markers has been reported for better understanding of the pathological conditions in cases with septicemia. MATERIALS AND METHODS: The correlation between the cardiorespiratory status based upon the PiCCO monitor (EVLW and PVPI) and inflammatory markers including C reactive protein, procalcitonin (PC), and Endotoxin Activity Assay (EAA) were evaluated in 11 severe cases that required treatment with a respirator in an intensive care unit. RESULTS: The EAA values were significantly higher in patients with abnormal EVLW at 0.46+/-0.20 compared to the normal EVLW group at 0.21+/-0.19 (p=0.0064). In a similar fashion, patients with abnormal PVPI values tended to have higher PC levels at 18.9+/-21.8 compared to normal PVPI cases at 2.4+/-2.2 (p=0.0676). On the other hand, PVPI was significantly higher in the abnormal EAA group at 3.55+/-0.48 in comparison with the normal EAA group at 1.99+/-0.68 (p=0.0029). The abnormal EAA group tended to have higher PVPI values than the normal EAA group. CONCLUSION: The EAA is a measurement method designed to estimate the activity of endotoxins in the whole blood. Our results suggest that the EAA value, which had the greatest correlation with lung disorders diagnosed by the PiCCO monitoring, reflects inflammatory reactions predominantly in the lungs.

Association of Endotoxins and Colon Polyp: A Case-Control Study

Endotoxins are known to be associated with the occurrence of various chronic diseases. This study was conducted to investigate the role of endotoxins in the pathogenesis of colon polyps through a case-control study. A total of 145 subjects (74 subjects in the polyp group and 71 subjects in the control group) had undergone a colonoscopy. Age, body mass index (BMI) and endotoxin levels were found to be significantly higher in the polyp group than in the control group. The endotoxin level was still significantly higher in the polyp group than in the control group, even after age and BMI had been adjusted (polyp group 0.108 +/- 0.007 EU/mL, control group 0.049 +/- 0.008 EU/mL, P < 0.001). In subgroup analysis, the endotoxin level significantly increased in accordance with the number of colon polyps (one-polyp group, 0.088 +/- 0.059 EU/mL; two-polyp group, 0.097 +/- 0.071 EU/mL; three-or-more-polyp group, 0.149 +/- 0.223 EU/mL). The endotoxin levels also significantly increased in groups with tubular adenoma with high-grade dysplasia (hyperplastic polyp group, 0.109 +/- 0.121 EU/mL; tubular adenoma with low grade dysplasia group, 0.103 +/- 0.059 EU/mL; tubular adenoma with high grade dysplasia group, 2.915 +/- 0.072 EU/mL). In conclusion, the serum level of endotoxins is quantitatively correlated with colon polyps.

Hyperdynamic circulatory response to iron deficiency, thalassaemia and sickle cell a anaemias

One of the most interesting areas of research in erythrocyte physiology is the interaction of haemoglobin with nitric oxide [NO]. These two molecules independently fulfill diverse and complex physiological roles, while together they delicately modulate microvascular perfusion in response to second-by-second changes in local metabolic demand, contributing to hypoxic vasodilatation. To highlight on pathophysiological mechanisms of hyperdynamic state in anemic patients as well as to investigate the relation between haemoglobin, NO, endothelin-1 [ET-1], cyclic guanosine monophosphate [c GMP] and endotoxins with hyperdynamic circulatory states in different anaemic patients. Forty five anaemic patients categorized in three groups each fifteen [Iron Deficiency Anaemic, Thalassaemic and Sickle Cell Anaemic patients] in addition to ten healthy controls. Pulse rate, systolic and diastolic blood pressure values were recorded for all subjects. Also, Haemoglobin types and level, serum iron and TIBC, NO, ET-1, c GMP and Endotoxin levels were measured for all. Significant increase in pulse rate and pressure, decrease in diastolic pressure in addition to elevation of NO, cGMP and Endotoxins whereas ET-1 significantly decline in all anemic patients. NO levels when correlated with Hb, ET-1 levels and diastolic blood pressure showed negative significant correlation, while. It was positively correlated with c GMP, Endotoxins, systolic blood pressure and pulse pressure in different anemic groups. Vasodilatation, the main cause of hyperdynamic accompanying anemia contributed to increase NO levels joint with reduction of ET-1 which mediated through c GMP pathway. Besides, en do endotoxemia may have some role in amplifying of NO production

La dexametasona, un inhibidor de la expresion de la oxido nitrico sintasa inducible, no modifica el estado hiperdinamico en ratas cirroticas / Dexamethasone, an inhibitor of the expression of the inducible nitric oxide synthase, does not modify the hyperdynamic state in cirrhotic rats

El aumento de la producción de óxido nítrico juega un papel importante en la fisiopatología de la cir- culación hiperdinámica asociada a la hipertensión portal. El probable mecanismo por el cual se produce este aumento no se encuentra aún bien definido. Con el objetivo de evaluar si la isoforma inducible es la responsable de estos cambios hemodinámicos, hemos estudiado el efecto de la administración de dexametasona, un inhibidor de la expresión de la óxido nítrico sintasa II, en ratas cirróticas tras la ligadura y sección del colédoco. Se determinaron los diferentes parámetros hemodinámicos sistémicos y esplácnicos, mediante la técnica de microesferas radiactivas, luego de la administración de dexametasona (3 mg/kg/día durante 3 días, ip) o su vehículo. En los animales cirróticos el efecto glucocorticoideo se puso de manifiesto a través de una disminución significativa en la ganancia de peso corporal y un moderado aumento, pero no significativo, de la presión arterial media. La administración de dexametasona no se asoció a cambios significativos de la resistencia vascular sistémica y esplácnica como así tampoco del flujo sanguíneo portal y presión portal. Similares resultados se observaron en el grupo de animales utilizados como controles. Se detectaron niveles significativamente más elevados de endotoxina en sangre portal y sistémica en 5 de 6 animales cirróticos. Nuestros resultados muestran que la administración de dexametasona no modifica los parámetros hemodinámicos sistémicos y esplácnicos en ratas cirróticas y endotoxémicas sugiriendo que la estimulación de la sintasa inducible no juega un papel importante en el aumento de la síntesis de óxido nítrico en la cirrosis.

Preoperative bile salt administration versus bile refeeding in obstructive jaundice.

BACKGROUND: Endotoxaemia due to intraluminal bile salt depletion may be a cause of renal failure in patients with obstructive jaundice. Administration of bile salts to these patients has been reported to decrease portal and systemic endotoxaemia during surgery and improve renal function. However, such changes have not been shown with bile refeeding. We compared the effect of preoperative bile salt administration with preoperative bile refeeding on renal function in patients with obstructive jaundice. METHODS: Sixteen patients with obstructive jaundice underwent percutaneous transhepatic biliary drainage--eight received oral bile salts (500 mg of sodium deoxycholate 8-hourly for 48 hours preoperatively) and the other 8 were refed the total bile output for the entire period of biliary drainage (median 13 days). Blood endotoxin levels and renal function were assessed before, during and after the operation. RESULTS: The number of patients with intraoperative portal and postoperative systemic endotoxaemia decreased after both forms of therapy. Renal function also improved in both the groups--all 4 patients with renal failure recovered. There was a significant increase in creatinine clearance postoperatively after bile salt therapy (from 65 ml/minute preoperatively to 87 ml/minute postoperatively). CONCLUSION: Refeeding of bile obtained by percutaneous catheter drainage is an effective, cost-free substitute for oral bile salts in patients with obstructive jaundice.

The effect of lethal endotoxaemia on the liver glycogen metabolism in guineapigs with common bile duct obstruction.

The effect of hepatocellular trauma due to bile reflux and endotoxaemia on liver glycogen metabolism was studied in guineapigs with common bile duct obstruction. Considerable drops in basal glycogen levels of hepatocytes from bile duct ligated (BDL) animals were recorded in comparison with the sham operated (SHAM) ones. However, the regurgitation of bile did not affect the basal blood glucose concentrations of BDL guineapigs. The circulating glucose was consumed, mainly reflecting the level of energy requirement of the peripheral tissues in the endotoxaemic SHAM pair-fed animals and the BDL group. The hepatic glycogen stores failed to prevent the SHAM group from becoming hypoglycaemic at the end of the eighth hour after endotoxin administration. Enhancement in glucose consumption and diminished liver glycogen indicated the necessity of glucose intake in the early phase of extrahepatic bile duct obstruction. It was concluded that both endogenous and exogenous glucose have limited value in improving energy metabolism in lethal endotoxaemia following bile duct obstruction.

Endotoxemia in patients with chronic liver disease

This study was conducted on 100 selected patients with chonic liver disease to find the relationship between plasma endotoxin level and the severity of liver disease. Twenty normal controls were in the study for Comparison. Patients were classified according to Child Classification into Child A group [30 Patients] and Child Band C groups [70 Patients]. Endotoxin level was assayed in the plasma of patients and controls using a quantitative chromogenic Limulus Amaebocyte Lysate Test [LAL]. The level of endotoxin was significantly in Child groups A, B and C than in the normal controls. Also it was found that the level of endotoxin in Child group B and C was significantly higher than in group A [P<0.05]. The endotoxin level was also significantly higher in cases with cirrhotic or mixed pattern than in those with schistosomal pattern [p=0.05]. It was found that the level of endotoxin correlated significantly with the incidence of ascites. It was concluded that endotoxaemia becomes more prominent with the progression of liver disease especially when associated with a mixed aetiology which may have its impact on the hepatic state and extrahepatic manifestationss

Papel del óxido nítrico en las alteraciones de la hemodinámica sistémica y esplácnica en un modelo experimental de hipertensión portal / Role of nitric oxide in the alterations of the systemic and splanchnic hemodynamics in a experimental model of portal hypertension

Se evaluó el efecto de la Nw-Nitro-L-arginina (L-NNA), un inhibidor específico de la síntesis de óxido nítrico, sobre la hemodinámica sistémica y esplácnica en un modelo experimental de hipertensión portal (ligadura parcial de la vena porta). La administración de L-NNA en los animales con hipertensión portal ocasionó un aumento significativo de la presión arterial media, una reducción del gasto cardíaco y un aumento de la resistencia vascular periférica. A nível de la hemodinámica esplácnica la L-NNA ocasionó un marcado incremento de la resistencia vascular esplácnica con la consecuente disminución del flujo sanguíneo portal. No se observaron cambios singnificativos en la presión portal. El pretratamiento con L-arginina inhibió los efectos hemodinámicos de la L-NNA. Similares niveles plasmáticos de endotoxina se detectaron en ambos grupos de animales. En el grupo control La L-NNA produjo un aumento de la presión arterial media; sin embargo, y a diferencia de lo observado en los animales on hipertensión portal, la administración de L-NNA no se acompaño de cambios significativos en el gasto cardíaco, flujo sanguíneo portal ni resistencia vascular esplácnica. Nuestros resultados sugieren que las alteraciones, tanto de la hemodinámica sistémica como esplácnica, asociadas a la hipertensión portal, pueden ser atenuadas mediante la administración de L-NNA. Asimismo, el aumento de la síntesis de óxido nítrico puede jugar un papel importante en la fisiopatogenia de estos trastornos hemodinámicos

Level of endotoxin and antilipid A in patients with chronic liver disease: the clinical presentation and the effect of treatment

This study was carried out on 25 selected patients with chronic liver diseases. All of them were subjected to complete medical examination, ultrasonography, endoscopy, liver function tests, prothrombin time and platelet count. The 25 patients were classified into Child A [5], Child B [7] and Child C [13]. The endotoxin level and antilipid A antibodies were assayed in the plasma and serum of the 25 patients and 10 healthy subjects. It was found that the endotoxin level and the antilipid A antibody response were significantly higher in child B and C than child A groups [P < 0.05 and P < 0.01]. The child group classification and the liver pattern correlated significantly with the endotoxin level and the antilipid A titre [P < 0.05 and P < 0.001]. Also the platelet count was significantly lower in child B and C than child A group [P < 0.05], the prothrombin time was prolonged in child B group but was significantly prolonged in child C group [P < 0.01]. The groups of patients classified as child B and C their plasma and serum were reassayed for the endotoxin level and antilipid A antibodies after receiving Neomycin therapy for decontamination of the bowel and minimization of the endotoxin production. Both the endotoxin level and the antilipid A antibody response decreased, the platelet count increased, the prothrombin time was shortened in both groups but in case of group C it was significantly shortened [P < 0.05]. The biochemical profile did not correlate neither with the endotoxin level nor the antilipid A antibody response. But after Neomycin administration the biochemical profile in group C improved. We concluded that Neomycin may be taken as a prophylactic precaution in severe liver affection, since it may help preventing the excessive accumulation of endotoxin and thus restores the liver function resulting into a delay in the progression of the liver disease. Also the antilipid A antibody assay may he used as an indication for increased in endotoxin level

relation between obstructive jaundice, endotoxemia and renal functions

This study showed that acute renal failure is one of the commonest complications in patients with obstructive jaundice and is a major cause of death. Besides, systemic endotoxemia is the prime cause of renal failure, treatment of endotoxemia by adding oral lactulose to the preoperative prepration of patients prevents acute renal failure and improves the renal functions. Bilirubin may have no role in occurrence of renal failure in these patients, the preoperative preparation with vitamin K, systemic antibiotics, preoperative hydration and mannitol may not be edequate and the addition of an antiendotoxic agent as lactulose is highly recommended

Falciparum malaria in naturally infected Saudi patients: high level endotoxemia in the venous blood infected with escherichia coli

During examination by transmission electron microscopy [TEM] of venous blood samples from twelve Saudi patients who were heavily infected with the human falciparum malaria parasite, three blood samples [25%] were found to contain numerous single, rod-shaped microorganism-like bacteria. Bacteriological tests identified these microorganisms as Escherichia coil, their confident limit of identification being 98%. Examination by TEM of the cultured bacteria has also identified their typical ultrastructural features. Detection of E. coli in the three blood samples has encouraged the examination for the occurence of endotoxaemia by the amoebocyte limulus lysate test. Endotoxin was likely detected and its level was found to be remarkably higher in blood samples infected with both the malaria parasite and bacteria than those only infected with the parasite, while none was detected in samples from five healthy volunteers. These findings suggest the possible responsibility of E. coli in increasing the endotoxaemia level in the blood of patients infected with falciparum malaria

Endotoxin and dengue haemorrhagic fever.

Limulus amoebocyte lysate test (LALT) was used to detect endotoxin-like substances in the plasma of 57 patients with dengue haemorrhagic fever and dengue shock syndrome (DHF/DSS), four patients with dengue fever and 20 control patients with other diseases. The LALT positivity rates in DHF/DSS and dengue fever patients were 43.9 and 25 per cent respectively, whereas all control patients were negative (p less than 0.0025). LALT positivity was highest on 5th and 6th days of admission with positive rates of 46 and 50 per cent respectively whereas the positive rates in those admitted on fourth and seventh days of admission were 29 and 33 per cent respectively. A follow-up in LALT positive patients showed a decline in the positive rates after admission. LALT positivity was observed in 48.8 per cent of DHF/DSS patients with shock and in 26.6 per cent of patients without shock.

Tachypleus lysate test for endotoxin in patients with Gram negative bacterial infections.

Amoebocyte lysate from the horseshoe crabs (Tachypleus gigas) which abounds in the Gulf of Thailand was used to detect endotoxin in patients with Gram-negative bacteremia, in patients with Gram-positive bacterial infections as well as in the control. The Tachypleus lysate test (TLT) was positive in 94.4% of 36 patients with Gram-negative bacteremia before initiation of antibiotic therapy. Only 4% of 50 healthy individuals were positive and all 7 patients with Gram-positive bacterial infections were negative. The threshold sensitivity of TLT was 0.625 micrograms endotoxin per ml of the plasma. In comparison with the commercial Limulus lysate test (LLT), the TLT was slightly more sensitive in exhibiting higher grade of reaction, eventhough the threshold sensitivity was the same.