Jelica Kurtovic

Synbiotic modulation of gut flora: Effect on minimal hepatic encephalopathy in patients with cirrhosis

Minimal hepatic encephalopathy (MHE) is an important disorder that may seriously impair daily functioning and quality of life in patients with cirrhosis. Treatment with lactulose is of benefit. The possible role of synbiotics (probiotics and fermentable fiber) has not been assessed. We screened 97 consecutive cirrhotic patients without overt hepatic encephalopathy for MHE using the number connection test and measurement of brainstem auditory evoked potentials. MHE, defined by abnormality on at least one test modality, was present in 58 (60%) patients. Fifty‐five of these patients with MHE were randomized to receive a synbiotic preparation (n = 20), fermentable fiber alone (n = 20), or placebo (n = 15) for 30 days. Cirrhotic patients with MHE were found to have substantial derangements in the gut microecology, with significant fecal overgrowth of potentially pathogenic Escherichia coli and Staphylococcal species. Synbiotic treatment significantly increased the fecal content of non‐urease‐producing Lactobacillus species at the expense of these other bacterial species. Such modulation of the gut flora was associated with a significant reduction in blood ammonia levels and reversal of MHE in 50% of patients. Synbiotic treatment was also associated with a significant reduction in endotoxemia. The Child‐Turcotte‐Pugh functional class improved in nearly 50% of cases. Treatment with fermentable fiber alone was also of benefit in a substantial proportion of patients. In conclusion, treatment with synbiotics or fermentable fiber is an alternative to lactulose for the management of MHE in patients with cirrhosis. (HEPATOLOGY 2004;39:1441–1449.)

Regulation of Toll‐like receptor‐2 expression in chronic hepatitis B by the precore protein

Toll‐like receptors (TLRs) play a key role in the innate immune response. The aim of this study was to examine the expression of TLR2 and TLR4 in chronic hepatitis B (CHB). The TLR2 and TLR4 expression on hepatocytes and Kupffer cells from fresh liver biopsies was measured from 21 patients with untreated hepatitis B e antigen (HBeAg)‐positive and HBeAg‐negative CHB. Parallel studies were also undertaken on monocytes from their peripheral blood. Expression of TLR2 on hepatocytes, Kupffer cells, and peripheral monocytes was significantly reduced in patients with HBeAg‐positive CHB in comparison with HBeAg‐negative CHB and controls, whereas it was significantly increased in HBeAg‐negative CHB compared with controls. The level of TLR4 expression did not differ significantly between the groups. These results were confirmed in vitro using hepatic cell lines transduced with recombinant HBV baculovirus expressing wild‐type HBV (HBeAg‐positive), precore stop codon (G1896A) mutant HBV (HBeAg‐negative). The functional relevance of these findings was established by the demonstration of significantly reduced cytokine production (TNF‐α) and phospho‐p38 kinase expression in the presence of the HBeAg. In the absence of HBeAg, HBV replication was associated with up‐regulation of the TLR2 pathway leading to increased TNF‐α production. Conclusion: This study demonstrates a potentially important interaction between HBeAg, HBV, and the innate immune response. (HEPATOLOGY 2007;45:102–110.)

Toll-like receptor expression in chronic hepatitis C: Correlation with pro-inflammatory cytokine levels and liver injury

Abstract.Background/AimsToll-like receptors (TLR’s) are critical receptors that promote innate immune responses to pathogen-associated molecular patterns. Activation of TLR’s leads to production of pro-inflammatory cytokines such as tumour necrosis factor (TNF)-α. This study investigates whether peripheral blood monocyte expression of TLR’s is disturbed in patients with chronic hepatitis C and whether levels of expression of these molecules are significantly correlated with hepatitis C virus (HCV) genotype, viral load, hepatic necroinflammatory activity, histological stage and circulating TNF-α concentrations.MethodsIn 18 non-cirrhotic patients with biopsy-proven, virologically-confirmed chronic hepatitis C and 32 controls, we measured expression of TLR2 and TLR4 on peripheral blood monocytes. HCV genotype, viral load, serum alanine aminotransferase (ALT) levels, histological stage of disease and circulating TNF-α and endotoxin levels were also determined.ResultsPeripheral blood monocyte expression of TLR2 and TLR4 were significantly increased in patients with chronic hepatitis C compared to controls, irrespective of HCV genotype or histological stage of disease. Circulating levels of TNF-α were also significantly increased in patients with chronic hepatitis C. In both the overall study cohort and patients with chronic hepatitis C, monocyte expression of TLR2, but not of TLR4, correlated significantly with serum TNF-α levels. In patients with chronic hepatitis C, monocyte expression of TLR2, but not of TLR4, also correlated significantly with serum ALT levels. Expression of TLR’s was not significantly correlated with viral load.ConclusionsUp-regulation of peripheral blood monocyte expression of TLR2 and TLR4 occurs in patients with chronic hepatitis C. Increased monocyte expression of TLR2, but not of TLR4, correlates significantly with both increased circulating TNF-α levels and hepatic necroinflammatory activity in this disorder.

Reduced Expression of Toll-Like Receptor 2 on Peripheral Monocytes in Patients with Chronic Hepatitis B

ABSTRACT Persistent infection with hepatitis B virus (HBV) likely depends on viral inhibition of host defenses. We report that chronic hepatitis B e antigen-positive HBV infection is associated with a significant reduction in peripheral blood monocyte expression of Toll-like receptor 2, a key component of innate immunity, thereby providing a mechanism by which wild-type HBV may establish persistent infection.

Lactose malabsorption in the elderly: role of small intestinal bacterial overgrowth.

Objective. The prevalence of lactose malabsorption (LM) is increased in the elderly, although the mechanisms responsible are still a matter of speculation. The objective of this study was to investigate the possible roles of reduced functional small intestinal absorptive area, lactase deficiency and small intestinal bacterial overgrowth (SIBO). Material and methods. Twenty Caucasian (Anglo-Celtic), asymptomatic, well-nourished, elderly volunteers (median age 79 years, range 70–94 years) with no clinically apparent predisposition to SIBO underwent a 50 g lactose breath hydrogen test (LBHT) and mannitol absorption test, the latter as an index of functional small intestinal absorptive area. Those with LM additionally underwent bacteriological assessment of small intestinal secretions and mucosal biopsy, to assess the contribution of SIBO and lactase deficiency, respectively, to the pathogenesis of LM in individual cases. The prevalence of SIBO was also determined in elderly subjects without LM. Twenty asymptomatic younger subjects (median age 29 years, age range 18–35 years) served as controls. All subjects were “hydrogen producers” in response to lactulose. Results. LM was evident in 10/20 (50%) elderly subjects and 1/20 (5%) younger subjects (p=0.003). Mannitol absorption did not differ significantly in elderly and younger subjects or in elderly subjects with and without LM. SIBO was documented in 9/10 (90%) elderly subjects with LM; eradication was associated with resolution of LM. Lactase deficiency was evident in only one elderly subject with LM. SIBO was evident in 2/10 (20%) elderly subjects without LM (p=0.005 compared to those with LM). Lactulose breath hydrogen test identified only 2/11 (18%) elderly subjects with SIBO. Conclusions. Increased prevalence of LM in the elderly is mostly due to clinically non-apparent SIBO, rather than mucosal factors. The lactulose breath hydrogen test cannot be relied upon to identify elderly subjects with SIBO, even in those without an anatomical predisposition.

Severe autoimmune hepatitis first presenting in the early post partum period

BACKGROUND & AIMS Autoimmune hepatitis (AIH) may run an aggressive clinical course if untreated. The influence of pregnancy on AIH is variable. Both flares in disease activity and remissions, often followed by a post partum flare, are well recognized. In contrast, definite AIH first presenting in the early post partum period has not been reported. METHODS We discuss a case series of 5 patients who developed severe AIH within 4 months post partum. RESULTS The diagnosis of AIH was definite based on internationally accepted criteria. Liver injury responded to conventional immunosuppressive therapy in all patients. Immune reactivation in the early post partum period may contribute to this entity. CONCLUSIONS AIH should be considered in the differential diagnosis of liver dysfunction first presenting in the early post partum period.

Equipment review: the molecular adsorbents recirculating system (MARS).

The molecular adsorbents recirculating system (MARS®) is a form of artificial liver support that has the potential to remove substantial quantities of albumin-bound toxins that have been postulated to contribute to the pathogenesis of liver cell damage, haemodynamic instability and multi-organ failure in patients with acute liver failure (ALF) and acute-on-chronic liver failure (AoCLF). These toxins include fatty acids, bile acids, tryptophan, bilirubin, aromatic amino acids and nitric oxide. Data from controlled clinical trials are limited so far. One of two studies performed on small numbers of patients with AoCLF suggest a survival benefit, but no controlled data are available in the ALF setting. Our preliminary experience with MARS therapy, instituted late in the clinical course of five patients with severely impaired liver function, including three with AoCLF precipitated by sepsis and two with liver dysfunction due to sepsis in the absence of pre-existing chronic liver disease, indicates some clinical efficacy. However, the overall survival rate (1 of 5; 20%) remained poor. More data obtained from larger cohorts of patients enrolled in randomised controlled studies will be required in both the AoCLF and ALF settings to identify categories of liver failure patients who might benefit most from MARS treatment, to ascertain the most appropriate timing of intervention and to determine the overall impact on outcome, including cost-effectiveness.

THIS ARTICLE HAS BEEN RETRACTED: An Australian Experience With the Molecular Adsorbents Recirculating System (MARS)

Abstract:  The molecular adsorbents recirculating system (MARS) is a form of artificial extracorporeal liver support which has the potential to remove substantial quantities of albumin‐bound toxins postulated to contribute to the pathogenesis of liver cell damage, hemodynamic instability and multi‐organ failure in patients with acute liver failure and acute‐on‐chronic liver failure (AoCLF). We assessed the efficacy of MARS therapy in a cohort of patients with severe liver damage unresponsive to intensive medical therapy. MARS therapy was instituted late in the clinical course of six patients with severely impaired liver function refractory to intensive medical therapy, including four with AoCLF precipitated by sepsis and two with liver dysfunction due to sepsis in the absence of pre‐existing chronic liver disease. Outcome measures included markers of hemodynamic stability, renal function, serum bilirubin and bile acid levels, arterial ammonia levels, the arterial ketone body (acetoacetate/β‐hydroxybutyrate) ratio, hepatic encephalopathy grade and the plasma disappearance rate of indocyanine green. The rates of discharge from the intensive care unit and in‐hospital mortality were determined. Our findings suggest that MARS treatment might be associated with some clinical efficacy even in patients with advanced multi‐organ dysfunction occurring in the setting of severe liver damage and in whom treatment is instituted late in the clinical course. However, the overall survival rate (1/6; 17%) was poor. More data obtained from larger cohorts of patients enrolled in randomized controlled studies will be required in order to identify categories of liver failure patients who might benefit most from MARS treatment and to ascertain the most appropriate timing of intervention.

An Australian experience with the molecular adsorbents recirculating system (Mars).

Abstract:  The molecular adsorbents recirculating system (MARS) is a form of artificial extracorporeal liver support which has the potential to remove substantial quantities of albumin‐bound toxins postulated to contribute to the pathogenesis of liver cell damage, hemodynamic instability and multi‐organ failure in patients with acute liver failure and acute‐on‐chronic liver failure (AoCLF). We assessed the efficacy of MARS therapy in a cohort of patients with severe liver damage unresponsive to intensive medical therapy. MARS therapy was instituted late in the clinical course of six patients with severely impaired liver function refractory to intensive medical therapy, including four with AoCLF precipitated by sepsis and two with liver dysfunction due to sepsis in the absence of pre‐existing chronic liver disease. Outcome measures included markers of hemodynamic stability, renal function, serum bilirubin and bile acid levels, arterial ammonia levels, the arterial ketone body (acetoacetate/β‐hydroxybutyrate) ratio, hepatic encephalopathy grade and the plasma disappearance rate of indocyanine green. The rates of discharge from the intensive care unit and in‐hospital mortality were determined. Our findings suggest that MARS treatment might be associated with some clinical efficacy even in patients with advanced multi‐organ dysfunction occurring in the setting of severe liver damage and in whom treatment is instituted late in the clinical course. However, the overall survival rate (1/6; 17%) was poor. More data obtained from larger cohorts of patients enrolled in randomized controlled studies will be required in order to identify categories of liver failure patients who might benefit most from MARS treatment and to ascertain the most appropriate timing of intervention.

Culture-proven small intestinal bacterial overgrowth as a cause of irritable bowel syndrome: response to lactulose but not broadspectrum antibiotics.

To the Editor: Much recent debate, to which we have contributed, has centered on whether small intestinal bacterial overgrowth (SIBO) may be a cause of the irritable bowel syndrome (IBS).1–6 This possibility had been raised by Pimentel et al.,5 who reported a double-blind, randomized, placebo-controlled study in which normalization of the lactulose breath hydrogen test (LBHT) following antibiotic treatment was found to correlate with symptom improvement in patients with IBS. The same group had earlier reported that 78% of patients with IBS had an abnormal LBHT, a finding interpreted to indicate that SIBO is common in IBS patients.5 We and others have expressed concern at the reliability of the LBHT for diagnosing SIBO,1,2,4,7 and suggested that further studies using a more reliable diagnostic test for SIBO, such as culture of small intestinal aspirate, should be performed so that the important issue of whether SIBO may contribute to IBS symptoms can be clarified.1,2 We report the case of a 48-year-old man who presented with a 27-year history of chronic diarrhea and intermittent abdominal pain, fulfilling Rome I criteria for IBS. There was no history of steatorrhea, weight loss, gastrointestinal bleeding, or previous gastrointestinal surgery. Previous investigations, including stool analyses for enteric pathogens and colonoscopy with colorectal and ileal biopsy, had revealed no abnormality. Upper gastrointestinal endoscopy with small intestinal biopsy was performed and demonstrated normal small intestinal mucosa and disaccharidase levels. Large duodenal diverticula were evident. A computerized tomography scan of the abdomen revealed extensive diverticulosis of the duodenum and jejunum. No pancreatic abnormality was apparent. Results of a full blood count, serum vitamin B12 and folate levels, iron studies, thyroid function tests, assays for hormonal causes of chronic diarrhea, and a 24-h fecal fat level were all within the reference range. Small intestinal aspirates for microbiological analysis were separately obtained from a duodenal diverticulum and the true duodenal lumen, using a sterile endoscopic technique.7 SIBO (total viable bacterial count 1012 colony forming units/ml [CFU/ml]; normal <105 CFU/ml7) was confirmed in aspirates from both sites. The overgrowth flora consisted of a mixed population of aerobes and facultative anaerobes, including Streptococcus spp and coliforms. The patient was treated with Augmentin Duo (amoxycillin 500mg and clavulanic acid; GlaxoSmithKline, Boronia, Victoria, Australia), 125mg b.d. orally, and metronidazole (Aventis Pharma, Lane Cove, New South Wales, Australia), 400mg t.d.s. orally for 4 weeks. Symptoms persisted at the end of treatment. A repeat small intestinal aspirate, obtained from the same duodenal diverticulum that had been sampled initially, demonstrated an unchanged total viable bacterial count (1012 CFU/ml). The patient was then treated with the nonabsorbable disaccharide, lactulose (b-d-galactopyranosyl-d-fructose; Solvay Pharmaceuticals, Sydney, Australia), 10g b.d. orally for 4 weeks, on the premise that fermentation of lactulose by small intestinal overgrowth flora to short chain fatty acids8 would acidify the small intestinal lumen and thereby reduce the small intestinal total viable bacterial count. Treatment was associated with resolution of diarrhea and abdominal pain within 3 days. A repeat small intestinal aspirate, obtained as above, yielded a markedly reduced total viable bacterial count (107 CFU/ml). An increased daily dose of lactulose (20g b.d. orally for 4 weeks) did not lead to a further reduction in the small intestinal viable bacterial count. Treatment was then suspended for 2 weeks, during which time symptoms rapidly recurred. A progress small intestinal aspirate demonstrated that the total viable bacterial count had increased to 1011 CFU/ml. Lactulose treatment was reinstituted (10g b.d. orally) and symptoms again rapidly resolved, in association with a reduction in the small intestinal total viable bacterial count to 107 CFU/ml (Fig. 1). The patient has remained asymptomatic over a 6-month period while receiving continued lactulose therapy. Our case is noteworthy in two respects. Firstly, the trend in our patient’s clinical status in relation to the total viable bacterial count in serial small intestinal aspirates provides compelling evidence that SIBO, in our patient presumably related to intestinal stasis associated with extensive small intestinal diverticulosis, may be a cause of IBS, at least in some patients. Secondly, this case indicates that broadspectrum antibiotic treatment may not always be effective for the treatment of SIBO. A possible alternative approach is the use of lactulose, the metabolism of which by gut flora to short chain fatty acids, thereby acidifying the gut lumen in the region of the bacterial overgrowth, may provide a form of “targeted” antibacterial therapy in the small intestine. The marked reduction in small intestinal total viable bacterial counts and rapid resolution of our patient’s chronic symptoms in association with lactulose treatment, along with the ongoing clinical response now, 6 months later, suggest that the value of this novel approach to the treatment of SIBO should be assessed in appropriate randomized, placebo-controlled studies.