Rifabutin based triple therapy for eradication of H. pylori primary and secondary resistant to tinidazole and clarithromycin.

BACKGROUND: Rifabutin has been empirically used in Helicobacter pylori infections resistant to triple therapy. There are no data on primary and secondary resistance to rifabutin and its use in specific cases. AIM: To analyse the susceptibility and resistance to rifabutin in H. pylori-positive patients with or without previous H. pylori therapy and to test the efficacy of rifabutin in H. pylori resistant to clarithromycin and tinidazole. METHODS: Four hundred and twenty H. pylori-positive patients without previous exposure to triple therapy and 104 patients who had already received one course of triple therapy underwent upper endoscopy for dyspeptic symptoms and H. pylori susceptibility test. Amoxicillin, clarithromycin, tinidazole and rifabutin were evaluated for resistance and susceptibility. Forty patients with primary resistance to both clarithromycin and tinidazole and with susceptibility to amoxicillin and rifabutin, and 65 patients with secondary resistance and susceptibility to the same antibiotics were identified. All these patients received a 10-day triple therapy with pantoprazole amoxicillin and rifabutin. Treatment success was evaluated by the 13C-Urea Breath test. RESULTS: In naive patients 23% of strains were resistant to clarythromycin, 35% to tinidazole, 9% to both antibiotics, and none was resistant to rifabutin In patients already treated the percentages of resistant strains were 76, 64.4, 62.5 and 1%, respectively. With rifabutin based triple therapy eradication rates were (Per Protocol and Intention-to-Treat analysis) 100 and 87.5% in primary resistance to clarithromycin and tinidazole and 82.2 and 78.5% in secondary resistance. CONCLUSION: H. pylori primary and secondary resistances to clarithromycin and tinidazole are high in our geographic area, while resistance to rifabutin is rare. Rifabutin-based triple therapy, can be successfully used in primary and secondary resistance to clarithromycin and tinidazole according to the in vitro susceptibility test.

Measurement of hepatic functional mass by means of 13C-methacetin and 13C-phenylalanine breath tests in chronic liver disease: comparison with Child-Pugh score and serum bile acid levels.

AIM: To evaluate and compare the clinical usefulness of 13C-phenylalanine and 13C-methacetin breath tests in quantitating functional hepatic mass in patients with chronic liver disease and to further compare these results with those of conventional tests, Child-Pugh score and serum bile acid levels. METHODS: One hundred and forty patients (50 HCV-related chronic hepatitis, 90 liver cirrhosis patients) and 40 matched healthy controls were studied. Both breath test and routine liver test, serum levels of cholic and chenodeoxycholic acid conjugates were evaluated. RESULTS: Methacetin breath test, expressed as 60 min cumulative percent of oxidation, discriminated the hepatic functional capacity not only between controls and liver disease patients, but also between different categories of chronic liver disease patients. Methacetin breath test was correlated with liver function tests and serum bile acids. Furthermore, methacetin breath test, as well as serum bile acids, were highly predictive of Child-Pugh scores. The diagnostic power of phenylalanine breath test was always less than that of methacetin breath test. CONCLUSION: Methacetin breath test represents a safe and accurate diagnostic tool in the evaluation of hepatic functional mass in chronic liver disease patients.

Breath tests with stable isotopes: have they a role in liver transplantation?

Evaluation of liver function is crucial in the overall management of patients with liver disease. In particular, patients with end-stage liver disease need accurate prognostic indicators to plan liver transplantation, and in this case, to manage their presence in the waiting list. Availability of predictors of clinical outcome is further essential after liver transplant, mainly to correctly diagnose and adequately treat complications, such as acute rejection, drug toxicity, liver dysfunction. Breath tests using labelled substrates selectively metabolized within the liver may represent an accurate diagnostic and prognostic tool in these clinical conditions, possibly with an adjuntive role to the most commonly used prognostic models (Child-Pugh and MELD scores). Promising results have been in fact recently obtained by the use of different substrates (aminopyrine, methacetin, erythromycin, methionine) which explore different metabolic function of the hepatocyte. The usefulness of breath tests has been documented in liver disease patients both before and after liver transplantation, in the early as well as in the late phase.

Safety of interferon beta treatment for chronic HCV hepatitis.

Hepatitis C is a major cause of liver-related morbidity and mortality worldwide. In fact, chronic hepatitis C is considered as one of the primary causes of chronic liver disease, cirrhosis and hepatocellular carcinoma, and is the most common reason for liver transplantation. The primary objectives for the treatment of HCV-related chronic hepatitis is to eradicate infection and prevent progression of the disease. The treatment has evolved from the use of alpha-interferon (IFNalpha) alone to the combination of IFNalpha plus ribavirin, with a significant improvement in the overall efficacy, and to the newer PEG-IFNs which have further increased the virological response, used either alone or in combination with ribavirin. Despite these positive results, in terms of efficacy, concerns are related to the safety and adverse events. Many patients must reduce the dose of PEG-IFN or ribavirin, others must stop the treatment and a variable percentage of subjects are not suitable owing to intolerance toward drugs. IFNbeta represents a potential therapeutic alternative for the treatment of chronic viral hepatitis and in some countries it plays an important role in therapeutic protocols. Aim of the present paper was to review available data on the safety of IFNbeta treatment in HCV-related chronic hepatitis. The rates of treatment discontinuation and/or dose modification due to the appearance of severe side effects during IFNbeta are generally low and in several clinical studies no requirements for treatment discontinuation and/or dose modifications have been reported. The most frequent side effects experienced during IFNbeta treatment are flu-like syndromes, fever, fatigue and injection-site reactions. No differences in terms of side-effect frequency and severity between responders and non-responders have been reported. A more recent study, performed to compare IFNbeta alone or in combination with ribavirin, confirmed the good safety profile of both treatments. Similar trends of adverse event frequency have been observed in subpopulations such as patients with genotype-1b HCV hepatitis unresponsive to IFNalpha treatment or with HCV-related cirrhosis and patients with acute viral hepatitis. If further studies will confirm the efficacy of combined IFNbeta and ribavirin treatment, this regimen could represent a safe and alternative therapeutic option in selected patients.

Gallbladder motility and functional gastrointestinal disorders.

Functional gastrointestinal disorders can be defined as 'a variable combination of chronic or recurrent gastrointestinal symptoms not explained by structural or biochemical abnormalities'. Motor disorders are considered to be one of the pathogenetic mechanisms of these symptoms; in fact, it has been hypothesized that the smooth muscle of the whole gastrointestinal tract could be involved. Gallbladder motility has been evaluated in patients with dysmotility-like dyspepsia, irritable bowel syndrome and biliary disorders without gallstones; results of these observations are often inconclusive, conflicting and not always useful from a clinical point of view. The aim of this review is to explore the relationship between gallbladder motility and functional gastrointestinal disorders from pathogenetic and physiopathological points of view, and also to define the possible impact of these observations on clinical practice.

Gallbladder cholesterol polyps and cholesterolosis.

Cholesterolosis of the gallbladder consists in an accumulation of cholesterol esters and triglycerides in the macrophages at gallbladder wall level and may be either diffuse or polypoid in form. A prevalence of 4-8% has been reported, particularly in the male sex; results concerning a relationship between cholesterolosis and lifestyle are controversial (alcohol intake, smoking habit), as well as the clinical and laboratory parameters, such as serum cholesterol and body mass index. Even more controversial is the relationship with gallstones which has been associated with the presence of cholesterol polyps only in a few surgical series. An increase in the activity of the cholesterol ester enzyme has been observed, in cholesterolosis patients, at gallbladder mucosa level which has led to the hypothesis of an increase in cholesterol ester deposit at this level; the hypothesis of an alteration in bile composition, in these patients, still remains to be elucidated. Ultrasonography is a sensitive tool in the diagnosis of cholesterolosis even if the use of echoendoscopy is becoming increasingly important in the differential diagnosis between benign and malignant polypoid lesions. Even if, in a few series, patients with polyps present a clinical pattern characterized by specific biliary symptoms, both in our experience and in that of others, symptoms are aspecific, the frequency of dyspeptic symptoms being comparable to that in the general population. The natural history of this lesion is, in general, benign and for polyps with size ranging from 6 mm to 10 mm a yearly follow-up with ultrasonography is advisable.