Update on ascites and hepatorenal syndrome

Application of mNGS in the Etiological Diagnosis of Thoracic and Abdominal Infection in Patients With End-Stage Liver Disease

Background

Despite the obvious advantages of metagenomic next-generation sequencing (mNGS) in etiological diagnosis of various infectious diseases, there are few reports on etiological diagnosis of suspected thoracic and abdominal infections in patients with end-stage liver disease (ESLD).

Methods

Seventy-three ESLD patients were enrolled from January 2019 to May 2021 due to suspected complicated thoracic and abdominal infections with poor response to empirical anti-infective treatment. Pleural effusion and ascites samples of these patients were collected for mNGS detection and conventional pathogen culture. The application value of mNGS in etiological diagnosis of thoracic and abdominal infections in ESLD patients was finally evaluated.

Results

A total of 96 pathogens were detected using mNGS method, including 47 bacteria, 32 viruses, 14 fungi, 2 Mycobacterium tuberculosis, and 1 parasite. The positive rate of mNGS reached 42.5%, which was significantly higher than that of conventional culture method (21.9%) (p = 0.008). Considering neutrophil counts, the overall positive rate of bacteria detection of both methods in Polymorphonuclear Neutrophils (PMN) ≥250/mm³ group was 64.3% and in PMN <250/mm³ group was 23.7%. Compared with the final clinical diagnosis, the agreement rate of mNGS in patients with positive bacteria detection and with suspected positive bacteria detection was 78.6% (11/14) and 44.4% (8/18), respectively. In addition, the agreement rate of mNGS was 66.7% (4/6, respectively) in patients with positive and suspected fungal detection. Interestingly, of the 11 patients with fungal detection, 5 had alcoholic liver disease, accounting for 45.5% of all patients with alcoholic liver disease. We also detected 32 strains of viruses using mNGS, mainly cytomegalovirus (62.5%).

Conclusions

The mNGS method is a useful supplement to conventional culture methods, which performs a higher positive rate, higher sensitivity, and broader pathogen spectrum, especially for rare pathogens and those difficult to culture. For ESLD patients, mNGS has great prospects in early etiological diagnosis of thoracic and abdominal infections. In addition, the cutoff values for the diagnosis of bacterial infection (PMN ≥250/mm³) in the thoracic and abdominal cavities may need to be redefined.

The safety and effectiveness of 2-liter polyethylene glycol plus ascorbic acid in patients with liver cirrhosis: A retrospective observational study

The safety of bowel-cleansing agents is an important issue in clinical practice, especially in patients with chronic diseases. Although the safety and efficacy of polyethylene glycol (PEG) has been investigated in many studies, few studies on PEG plus ascorbic acid exist. In this study, we compared the safety of 2 bowel-cleansing agents for patients with liver cirrhosis: 2-liter PEG (2 L PEG) plus ascorbic acid versus 4-liter PEG (4 L PEG). We performed a retrospective study on colonoscopy in patients with liver cirrhosis. Patients referred for colonoscopy were divided into 2 groups: 2 L PEG plus ascorbic acid (n = 105) and 4 L PEG (n = 61). Safety was assessed by comparing the clinical factors and laboratory findings as follows: blood biochemistry, electrolytes, weight change, and bowel-cleansing quality. Serum electrolytes, laboratory findings, and body weight showed no significant change between the 2 groups. There was no significant change in clinical factors before and after bowel preparation in the PEG group or the PEG plus ascorbic acid group. The acceptability and compliance of patients was better in the 2 L PEG plus ascorbic acid than the 4 L PEG group. In subgroup analysis, patients with compensated or decompensated cirrhosis showed no increased risk of electrolyte imbalances after bowel preparation. Child-Pugh scores did not influence the outcome after bowel cleansing. Successful cleansing was mostly achieved in both groups. Our analysis showed that of the use of 2 L PEG plus ascorbic acid could be a safe choice for colonoscopy in patients with liver cirrhosis.

Insufficient evidence of benefit regarding mortality due to albumin substitution in HCC-free cirrhotic patients undergoing large volume paracentesis

BACKGROUND

Current guidelines for clinical practice recommend the infusion of human albumin after large volume paracentesis. After inspecting the current evidence behind this recommendation, we decided to conduct a systematic review and meta-analysis in order to address the effect of albumin on mortality and morbidity in the context of large volume paracentesis.

METHODS

We performed a comprehensive search of large databases and abstract books of conference proceedings up to March 15th 2016 for randomized controlled trials, testing the infusion of human albumin against alternatives (vs no treatment, vs plasma expanders; vs vasoconstrictors) in HCC-free patients suffering from cirrhosis. We analyzed these trials with regard to mortality, changes in plasma renin activity (PRA), hyponatremia, renal impairment, recurrence of ascites with consequential re-admission into hospital and additional complications. We employed trial sequential analysis in order to calculate the number of patients required in controlled trials to be able to determine a statistically significant advantage of the administration of one agent over another with regard to mortality.

RESULTS

We were able to include 21 trials totaling 1277 patients. While the administration of albumin prevents a rise in PRA as well as hyponatremia, no improvement in strong clinical endpoints such as mortality could be demonstrated. Trial sequential analysis showed that at least 1550 additional patients need to be recruited into RCTs and analyzed with regard to this question in order to detect or disprove a 25% mortality effect.

CONCLUSIONS

There is insufficient evidence that the infusion of albumin after LVP significantly lowers mortality in HCC-free patients with advanced liver disease.

The clinical management of abdominal ascites, spontaneous bacterial peritonitis and hepatorenal syndrome: a review of current guidelines and recommendations

Several pathogenic processes have been implicated in the development of abdominal ascites. Portal hypertension, most usually in the context of liver cirrhosis, can explain about 75% of the cases, whereas infective, inflammatory and infiltrative aetiologies can account for the rest. In this article, we discuss the consensus best practice as published by three professional bodies for the management of ascites, spontaneous bacterial peritonitis (SBP) and hepatorenal syndrome (HRS). The aim of this study was to compare available clinical guidelines and identify areas of agreement and conflict. We carried out a review of the guidance documentation published by three expert bodies including the British Society of Gastroenterology, the European Association for the Study of the Liver (EASL) and the American Association for the Study of Liver Diseases (AASLD), as well as a wider literature search for ascites, SBP and HRS. Abdominal ultrasonography, diagnostic paracentesis and ascitic fluid cultures are recommended by all three guidelines, especially when there is strong clinical suspicion for infection. EASL and AASLD advocate the use of ascitic amylase and mycobacterial cultures/PCR when there is strong suspicion for tuberculosis and pancreatitis, respectively. Ascitic cytology can be useful when cancer is suspected and has a good diagnostic yield if performed correctly. EASL supports the use of urinary electrolytes for all patients; however, the British Society of Gastroenterology and AASLD only recommend their use for therapy monitoring. All three societies recommend cefotaxime as the antibiotic of choice for SBP and large-volume paracentesis for the management of ascites greater than 5 l in volume. For HRS, cautious diuresis, volume expansion with albumin and the use of vasoactive drugs are recommended. There appears to be good concordance between recommendations by the European, American and British guidelines for the management of ascites and the possible complications arising from it.

Complications of cirrhosis. A 50 years flashback

In patients with cirrhosis and portal hypertension, it is largely the frequency and severity of complications relating to the diseased liver, degree of portal hypertension and hemodynamic derangement that determine the prognosis. It can be considered as a multiple organ failure that apart from the liver involves the heart, lungs, kidneys, the immune systems and other organ systems. Progressive fibrosis of the liver and subsequent metabolic impairment leads to a systemic and splanchnic arteriolar vasodilatation. With the progression of the disease development of portal hypertension leads to formation of esophageal varices and ascites. The circulation becomes hyperdynamic with cardiac, pulmonary as well as renal consequences for dysfunction and reduced survival. Infections and a changed cardiac function known as cirrhotic cardiomyopathy may be involved in further aggravation of other complications such as renal failure precipitating the hepatorenal syndrome. Patients with end-stage liver disease and related complications as for example the hepatopulmonary syndrome can only radically be treated by liver transplantation.

Management of cirrhotic ascites

The most common complication to chronic liver failure is ascites. The formation of ascites in the cirrhotic patient is caused by a complex chain of pathophysiological events involving portal hypertension and progressive vascular dysfunction. Since ascites formation represents a hallmark in the natural history of chronic liver failure it predicts a poor outcome with a 50% mortality rate within 3 years. Patients with ascites are at high risk of developing complications such as spontaneous bacterial peritonitis, hyponatremia and progressive renal impairment. Adequate management of cirrhotic ascites and its complications betters quality of life and increases survival. This paper summarizes the pathophysiology behind cirrhotic ascites and the diagnostic approaches, as well as outlining the current treatment options. Despite improved medical treatment of ascites, liver transplantation remains the ultimate treatment and early referral of the patient to a highly specialized hepatology unit should always be considered.

Rifaximin therapy and hepatic encephalopathy: Pros and cons

Hepatic encephalopathy (HE) is the second most common major complication in cirrhotics and it significantly impacts quality of life. Therapeutic approaches for HE treatment and prevention mainly continue to rely on ammonia-lowering strategies and non-absorbable disaccharides are currently considered the cornerstone therapy. Non-absorbable antibiotics, such as neomycin and paramomycin, are effective in treatment of acute HE episodes but their prolonged use for recurrence prevention is hampered by possible side-effects. To overcome these limitations, rifaximin use has been proposed. Rifaximin has been shown to be not superior to non-absorbable disaccharides for either HE treatment or prevention, with a similar incidence of side-effects. Cirrhosis significantly increases rifaximin absorption and this could be a cause for concern. Following long-term rifaximin therapy, Clostridium difficile colitis has been observed and Candida albicans has been isolated from 20% of patients. In addition, selection of resistant mutants of both Gram-negative and -positive bacteria in the gastrointestinal tract cannot be definitely ruled out. Electrolyte alterations (sodium and potassium) have been reported during rifaximin therapy, a warning for its long-term use in cirrhotics. Moreover, a potential interference with vitamin K production should be considered which could further impair the already altered clotting status of these patients. The therapeutic cost of rifaximin is markedly higher than non-absorbable disaccharides. While waiting for further safety data, caution should be used to limit the use of rifaximin therapy for a very short-term period in selected HE cirrhotics not responding to non-absorbable disaccharides.

Comparison of the effects of femoral versus portal vein administration of vasodilators on portal hemodynamics in cirrhotic rats with portal hypertension

AIM: To compare the effects of femoral versus portal vein administration of vasodilators on portal hemodynamics in rats with liver cirrhosis.

METHODS: Forty-two male Wistar rats with liver cirrhosis induced with carbon tetrachloride and alcohol were divided randomly and equally into six groups, which underwent femoral or portal vein injection of nitroglycerol (NG), prostaglandin E₁(PGE₁) or isotonic sodium chloride (NaCl), respectively. Hemodynamic parameters, including portal vein diameter (PVD), portal flow rate (PFR) and portal vein inflow (PVF), were measured after drug injection.

RESULTS: There were no significant differences in PVD, PVF and PFR between rats undergoing femoral and portal vein injection of NaCl (P = 0.1742, 0.2372 and 0.6566). PVD was increased significantly in cirrhotic rats that were given vasodilator agents, however, there were no significant differences in PVD changes between rats undergoing portal and femoral vein administration (P = 0.0516 and 0.1225). PVF was less increased in rats undergoing portal vein administration of NG and PGE₁than in those undergoing femoral vein administration of NG and PGE₁ (P < 0.0001). Comparing with pre-injection, PFR increased in rats undergoing femoral vein administration of NG and PGE₁, but decreased in rats undergoing portal vein administration NG and PGE₁ after dosed 10, 20 min [NG_f: 4.98 mm/(s•100 g) ± 0.62 mm/(s•100 g), 4.31 mm/(s•100 g) ± 0.46 mm/(s•100 g) vs 3.62 mm/(s•100 g) ± 0.38 mm/(s•100 g); PGE_1f: 3.96 mm/(s•100 g) ± 0.56 mm/(s•100 g), 4.18 mm/(s•100 g) ± 0.50 mm/(s•100 g) vs 3.63 mm/(s•100 g) ± 0.47 mm/(s•100 g) P < 0.0001; NG_p: 2.93 mm/(s•100 g) ± 0.22 mm/(s•100 g), 3.13 mm/(s•100 g) ± 0.21 mm/(s•100 g) vs 3.70 mm/(s•100 g) ± 0.48 mm/(s•100 g); PGE_1p: 3.65 mm mm/(s•100 g) ± 0.22 mm/(s•100 g), 3.36 mm/(s•100 g) ± 0.21 mm/(s•100 g) vs 3.84 mm/(s•100 g) ± 0.19 mm/(s•100 g), P< 0.001].

CONCLUSION: NG and PGE₁ are able to increase portal vein flow in cirrhotic rats with portal hypertension. Administration of vasodilators via the portal vein is not superior to that via the femoral vein in increasing PVF in cirrhotic rats with portal hypertension.

Ascites: pathogenesis and therapeutic principles

Ascites is a classic complication of advanced cirrhosis and it often marks the first sign of hepatic decompensation. Ascites occurs in more than 50% of patients with cirrhosis, worsens the course of the disease, and reduces survival substantially. Portal hypertension, splanchnic vasodilatation, liver insufficiency, and cardiovascular dysfunction are major pathophysiological hallmarks. Modern treatment of ascites is based on this recognition and includes modest salt restriction and stepwise diuretic therapy with spironolactone and loop-diuretics. Tense and refractory ascites should be treated with large volume paracentesis followed by plasma volume expansion or transjugular intrahepatic portosystemic shunt. Ascites complicated by spontaneous bacterial peritonitis requires adequate treatment with antibiotics. New potential treatment strategies include the use of vasopressin V(2)-receptor antagonists and vasoconstrictors. Since formation of ascites is associated with a poor prognosis, and treatment of fluid retention does not substantially improve survival, such patients should always be considered for liver transplantation.

Liver-kidney pathophysiological interrelationships in liver diseases

On the basis of several clinical and experimental researches, it is possible today to deepen the different mechanisms regarding kidney and liver relationships. However, the most studied field remains the renal function during liver disease. These alterations can be divided into: 1. Renal functional impairment is mainly considered due to hemodynamic derangement with a progressive decrease in peripheral vascular resistance (PVR) and an increase in cardiac output and rate, characteristic of hyperdynamic circulation, and outer cortex renal ischemia. Two principal forms of RFI characterize the hepatorenal syndrome (HRS) while in the first stage is based on the simple decrease in renal clearances with avid sodium retention. 2. Metabolic renal damage is principally due to abnormal serum levels of bile acids, bilirubin and perhaps toxic hepatic molecules which induce tubular dysfunction leading to RTA, of which type I, in the incomplete form, is the most common, varying between 30% and 50% of cases. It is mainly studied during cholestatic disease. 3. Organic renal impairment is principally based on immunological response to viral antigens and abnormal hepatic products which lead to the presence of immunocomplexes and cryoglobulins on the blood which tend to be deposited in the subendothelial and subepithelial glomerular areas, inducing complement activation, mesangial cell proliferation and monocyte-macrophage cell infiltration.

Pathogenetic background for treatment of ascites and hepatorenal syndrome

Ascites and hepatorenal syndrome (HRS) are the major and challenging complications of cirrhosis and portal hypertension that significantly affect the course of the disease. Liver insufficiency, portal hypertension, arterial vasodilatation, and systemic cardiovascular dysfunction are major pathophysiological hallmarks. Modern treatment of ascites is based on this recognition and includes modest salt restriction and stepwise diuretic therapy with spironolactone and loop diuretics. Tense and refractory ascites should be treated with a large volume paracentesis, followed by volume expansion or transjugular intrahepatic portosystemic shunt. New treatment strategies include the use of vasopressin V(2)-receptor antagonists and vasoconstrictors. The HRS denotes a functional and reversible impairment of renal function in patients with severe cirrhosis with a poor prognosis. Attempts of treatment should seek to improve liver function, ameliorate arterial hypotension and central hypovolemia, and reduce renal vasoconstriction. Ample treatment of ascites and HRS is important to improve the quality of life and prevent further complications, but since treatment of fluid retention does not significantly improve survival, these patients should always be considered for liver transplantation.

Development of hepatorenal syndrome in bile duct ligated rats

AIM: To evaluate in bile duct ligated rats whether there were progressive alterations of renal function without changes in histopathology.

METHODS: Male Wistar rats were submitted to sham-surgery or bile duct ligation (BDL) and divided according to the post-procedure time (2, 4 and 6-wk). To determine renal function parameters, rats were placed in metabolic cages and, at the end of the experiment, blood and urine samples were obtained. Histology and hydroxyproline content were analyzed in liver and renal tissue.

RESULTS: Rats with 2 wk of BDL increased free water clearance (P = 0.02), reduced urinary osmolality (P = 0.03) and serum creatinine (P = 0.01) in comparison to the sham group. In contrast, rats at 6 wk of BDL showed features of HRS, including significant increase in serum creatinine and reductions in creatinine clearance, water excretion and urinary sodium concentration. Rats with 4 wk of BDL exhibited an intermediate stage of renal dysfunction. Progressive hepatic fibrosis according to post-procedure time was confirmed by histology. The increased levels of liver hydroxyproline contrasted with the absence of structural changes in the kidney, as assessed by histology and unchanged hydroxyproline content in renal tissue.

CONCLUSION: Our data show that BDL produced progressive renal dysfunction without structural changes in the kidney, characterizing HRS. The present model will be useful to understand the pathophysiology of HRS.

An appraisal of the strengths and weaknesses of newborn and juvenile rat models for researching gastrointestinal development

Research on the impact of bioactive compounds on the development and functional maturation of the gastrointestinal (GI) tract using newborn and juvenile rats has greatly contributed to the knowledge of GI physiology and to the improved clinical management of both premature and full-term newborns. Of the animal models available, two types have been described for use with young rats – maintenance models and substitution models. Maintenance models are those in which the young are reared with the dam and therefore benefit from continuation of natural nutrition and maternal care. Substitution models are those in which the young are reared in the absence of the dam using artificially formulated milk delivered by various means into specific GI sites. In this review, we describe these models and their operation, and discuss the strengths and weaknesses of each. Attention is also given to questions of scientific validity and some animal welfare issues raised by the use of these models.

Review article: Management of ascites and associated complications in patients with cirrhosis

BACKGROUND

Ascites is the most common complication of cirrhosis, associated with an expected survival below 50% after 5 years. Prognosis is particularly poor for patients with refractory ascites and for those developing complications, including spontaneous bacterial peritonitis (SBP) and hepatorenal syndrome (HRS).

AIM

To provide an evidence-based overview of the pathophysiology, diagnosis and clinical management of ascites secondary to liver cirrhosis.

METHODS

Review based on relevant medical literature.

RESULTS

Portal hypertension, splanchnic vasodilatation and renal sodium retention are fundamental in the pathophysiology of ascites formation. The SAAG (serum-ascites albumin gradient) allows reliable assessment of the cause of ascites. The majority of cirrhotic patients with ascites can be managed with dietary sodium restriction in combination with diuretic agents. Large volume paracentesis with albumin suppletion and TIPS are therapeutic options in patients with refractory ascites. Prophylactic antibiotics for SBP should be given in certain patient populations.

CONCLUSIONS

Recent advances in the diagnosis and treatment of ascites and associated complications have improved the medical management and poor prognosis of patients with these manifestations of advanced liver disease. Early diagnosis, adequate treatment and focus on prevention of complications remain essential as well as timely referral for liver transplantation.

Acute renal dysfunction in liver diseases

Renal dysfunction is common in liver diseases, either as part of multiorgan involvement in acute illness or secondary to advanced liver disease. The presence of renal impairment in both groups is a poor prognostic indicator. Renal failure is often multifactorial and can present as pre-renal or intrinsic renal dysfunction. Obstructive or post renal dysfunction only rarely complicates liver disease. Hepatorenal syndrome (HRS) is a unique form of renal failure associated with advanced liver disease or cirrhosis, and is characterized by functional renal impairment without significant changes in renal histology. Irrespective of the type of renal failure, renal hypoperfusion is the central pathogenetic mechanism, due either to reduced perfusion pressure or increased renal vascular resistance. Volume expansion, avoidance of precipitating factors and treatment of underlying liver disease constitute the mainstay of therapy to prevent and reverse renal impairment. Splanchnic vasoconstrictor agents, such as terlipressin, along with volume expansion, and early placement of transjugular intrahepatic portosystemic shunt (TIPS) may be effective in improving renal function in HRS. Continuous renal replacement therapy (CRRT) and molecular absorbent recirculating system (MARS) in selected patients may be life saving while awaiting liver transplantation.

Comparison of Red Cell and Whole Blood Volume as Performed Using Both Chromium-51–Tagged Red Cells and Iodine-125–Tagged Albumin and Using I-131–Tagged Albumin and Extrapolated Red Cell Volume

BACKGROUND

Our facility's current blood volume measurement protocol has involved separate measurement of plasma and red cell volumes. The purpose of this study is to determine whether measurement with a recently FDA-approved, one-compartment semiautomated system provides similar accuracy.

METHODS

Blood volume measurement was performed on 27 volunteers using our current protocol followed immediately by semiautomated plasma volume measurement and red cell volume calculation with a recently available system (BVA-100).

RESULTS

Double labeling for red cell mass and plasma volume required approximately 5 hours of technologist and processing time; measurement with the BVA-100 required approximately 1.5 hours or less, a saving of 3.5 hours time per test. Whole blood and red cell volume each exhibited a Pearson correlation of 0.96, and plasma volume exhibited a Spearman rank correlation of 0.90. Average percent difference between the measurement methods was 2.2% for whole blood volume, 0.9% for red cell volume, and 3.3% for plasma volume. The mean ratio between the mean body hematocrit and measured venous hematocrit (f ratio) was 0.91, with a standard deviation of 0.0405.

CONCLUSIONS

The BVA-100 has significant advantages in terms of time and ease of use. The 2 tests can be considered equivalent methods for blood volume measurements.

Transthoracic electrical bioimpedance: a non-invasive technique for the evaluation of the haemodynamic alterations in patients with liver cirrhosis

BACKGROUND/AIM

Transthoracic electrical bioimpedance is a non-invasive technique for the evaluation of systemic haemodynamics. Compared to Doppler ultrasound, it has the advantage of being operator-independent, providing continuous monitoring and being less influenced by postural changes. Until now, transthoracic electrical bioimpedance has been applied to a very limited extent in liver cirrhosis. We, therefore, aimed to compare transthoracic electrical bioimpedance and echocardiography in the assessment of haemodynamic status in cirrhotic patients.

PATIENTS/METHODS

Thirteen patients with compensated cirrhosis, 10 patients with cirrhosis and ascites and 12 controls were enrolled. Haemodynamic parameters (stroke volume, cardiac output, heart rate, mean arterial pressure and vascular peripheral resistance) were assessed simultaneously by transthoracic electrical bioimpedance monitoring with BioZ.com for at least 10 min and Doppler ultrasound.

RESULTS

The absolute mean values of haemodynamic parameters obtained by the two techniques were quite similar in all groups; furthermore, a good agreement between transthoracic electrical bioimpedance and echocardiography measurements was found for all the parameters. Finally, transthoracic electrical bioimpedance proved easy to employ and provided continuous real-time monitoring of cardio-circulatory variations.

CONCLUSIONS

The present study showed a significant correlation between transthoracic electrical bioimpedance and echocardiography in the assessment of systemic haemodynamics in patients with cirrhosis, supporting the employment of transthoracic electrical bioimpedance in pathophysiological studies requiring real-time continuous monitoring of haemodynamic parameters.

Pathophysiological basis of pharmacotherapy in the hepatorenal syndrome

Hepatorenal syndrome (HRS) is a functional and reversible impairment of renal function in patients with severe cirrhosis. Major pathophysiological elements include liver dysfunction, a circulatory derangement with central hypovolaemia and neurohumoral activation of potent vasoactive systems leading to a pronounced renal vasoconstriction. The prognosis of patients with HRS is poor but recent research has spread new enthusiasm for treatment. Efforts at treatment should seek to improve liver function, to ameliorate arterial hypotension and central hypovolaemia, and to reduce renal vasoconstriction. Therefore a combined approach should be applied with reduction of portal pressure with e.g. ss-adrenergic blockers and transjugular intrahepatic portosystemic shunt (TIPS), with amelioration of arterial hypotension and central hypovolaemia with vasoconstrictors such as terlipressin and plasma expanders. New experimental treatments with endothelin- and adenosine antagonists and long-acting vasoconstrictors may have a future role in the management of HRS.

Hepatic encephalopathy and Helicobacter pylori: a critical reappraisal

Hepatic encephalopathy (HE) is a frequent complication of liver cirrhosis, and plasma ammonia plays a pivotal role in its pathogenesis. Ammonia disposal in cirrhotics depend on intricately balanced enzyme and transport systems, involving liver, large and small bowel, muscle, and kidney. Recently, it has been suggested that Helicobacter pylori could contribute to hyperammonemia in cirrhotics, but conflicting data are available in the literature. This is a systematic review of experimental (animals and humans), epidemiological, case-control, and prospective studies, to evaluate the arguments in favor and against the role of H. pylori in HE pathogenesis. Although H. pylori produces ammonia in the stomach, several studies have shown that both basal ammonia levels and HE prevalence did not significantly differ between cirrhotics with and without infection. Moreover, some prospective studies have documented that both blood ammonia levels and mental status in HE cirrhotics are not significantly affected by H. pylori eradication. Even if a small sub-group of cirrhotics with both a high bacterial density and more severe hepatic impairment seems to benefit by bacterial eradication, data indicate that ammonia production in the stomach by H. pylori urease appears to be inadequate to clinically affect ammonia disposal in the majority of cirrhotic patients. Further studies are warranted in this field.

Helicobacter pylori diagnosis in patients with liver cirrhosis

BACKGROUND

In cirrhotics, Helicobacter pylori infection is the major cause of peptic lesions, which are an important cause of upper intestinal haemorrhage in these patients. However, some diagnostic methods are not accurate for H. pylori detection in cirrhotics.

AIMS

The study assessed the accuracy of different diagnostic methods for H. pylori detection in cirrhotics with and without gastroduodenal lesions.

METHODS

The study population comprised of 53 cirrhotics. All patients underwent upper endoscopy: three biopsies were taken in the antrum and three in the gastric body. Four biopsies were used for Giemsa staining, while two were used for a rapid urease test. A blood sample was obtained for serology using Western blotting, and a [13C]urea breath test was performed in all patients. Histological assessment was regarded as the gold standard for diagnosis of H. pylori infection.

RESULTS

H. pylori infection was detected at histological assessment in 28 (52.8%) patients. The [13C]urea breath test, rapid urease test, and serology were positive in 27 (51%) patients, 23 (43.4%) patients, and 34 (64.1%) patients, respectively. Sensitivity and specificity were 92.9 and 96% for the [13C]urea breath test, 78.6 and 96% for the rapid urease test, and 78.6 and 52% for serology.

CONCLUSIONS

The [13C]urea breath test is very accurate in cirrhotics, whilst both serology and the rapid urease test give disappointing results.