The impact of rifaximin in the prevention of bacterial infections in cirrhosis.

OBJECTIVE: Bacterial infections are a leading factor in the progression from compensated to decompensated cirrhosis, with consequent worsening of the prognosis, and concerted efforts have been made to reduce infections and improve the survival rate of these patients. We retrospectively investigated the rate of infections in hospitalized cirrhotic patients under treatment with rifaximin. PATIENTS AND METHODS: We enrolled 649 patients whose clinical and personal data, prescribed therapy, microbiological findings and laboratory tests were collected from previous discharge letters and our institution database. The efficacy of rifaximin in preventing several types infection was evaluated by comparing outcomes for rifaximin-treated patients vs patients receiving no antibiotic treatment. RESULTS: The risk of developing selected bacterial infections was significantly lower in patients treated with rifaximin (OR 0.29; 95% CI 0.20-0.40, p < 0.001). CONCLUSIONS: Continuous treatment with rifaximin may prevent bacterial infections in cirrhotic patients.

Does active hepatitis C virus infection increase the risk for infection due to Staphylococcus aureus?

Infections with Staphylococcus aureus may be more frequent in subjects with active hepatitis C virus (HCV) infection. In this retrospective dual-cohort study, we sought to determine whether persons with active HCV infection (positive HCV antibody, detectable blood HCV RNA) were at greater risk of S. aureus infection than those with spontaneously resolved HCV infection (positive HCV antibody, negative blood HCV RNA). Based on prestudy power calculation, we included 231 subjects with active HCV and 116 subjects with resolved HCV infection. The two groups were well matched at baseline, except that subjects with active HCV had a higher mean Charlson's comorbidity index (2.2 vs. 1.3; p < 0.0001). Cohorts were followed for a mean of 3.67 years. Thirty-one of the 231 (13%) subjects with active HCV infection developed ≥1 S. aureus infection(s) as compared to 4/116 (3.4%) subjects with resolved HCV (p = 0.004), with a trend towards more recurrent S. aureus infections in subjects with active HCV infection. The S. aureus infections were mostly serious, necessitating hospitalization and intravenous antibiotics. In the logistic regression, factors that independently predicted S. aureus infection were active HCV and Charlson's comorbidity index. Our regression models confirmed that the enhanced susceptibility to S. aureus infections was related to active HCV infection and not attributable solely to the increased number of comorbidities [adjusted odds ratio (OR) = 3.3, 95% confidence interval (CI) 1.1-9.8; p = 0.03]. This study shows that subjects with active HCV infection have a significantly higher incidence of serious S. aureus infections than those with spontaneously resolved HCV, even after adjustment for comorbidities.

General issues on microbial translocation in HIV-infected patients.

The lumen of the gastrointestinal tract is home to an enormous quantity of different bacterial species that thrive in an often symbiotic relationship with the host. It is the principal source of microbial products because of its massive bacterial load. Injury to the immune component of the gastrointestinal mucosal surface, along with damage to the intestinal epithelial microenvironment with its antimicrobial functions, may affect systemic immune activation during the chronic phase of HIV infection through the increased translocation of luminal microbial products. Moreover, microbial translocation, which is defined as "the passage of both viable and nonviable microbes and microbial products such as endotoxin across anatomically intact intestinal barrier", may be a fundamental mechanism through which HIV accelerates progression of chronic viral hepatitis. Improvements in the tools available to microbiota research, and especially advancement of our knowledge in this area may help us in controlling the evolution of HIV disease, although population complexity and diversity between individuals make this challenging.

Which factors predict the behavior of ventricular extrasystoles in athletes over time?

Spontaneous behavior of ventricular extrasystoles (VE) was analysed. From a database containing 578 athletes with VE, 84 males and 11 females (29.9 ± 18.1 years) having ≥ 100 VE or repetitive VE [ventricular couplets (VC) or ventricular tachycardias (VT)] at first 24-hour Holter electrocardiographic monitoring (24-h-HM) (baseline) and at least 1-year of follow-up (3.1 ± 2.2 years) over the past 10 years were selected. The baseline was compared with the last 24-h-HM to establish DVE (VE reduction of at least 98%/24 h in the absence of VC or VT). SDVE was calculated as standard deviation of the number of VE on serial 24-h-HMs. DVE and SDVE were considered as dependent variables. Independent variables were: age, sex, type of sport, symptoms, baseline VE rate (BVE), baseline VC and VT, VE morphology, VE behavior during the baseline training session, disqualification from competitive sports, echocardiographic abnormalities. DVE occurred in 32 athletes (34%). SDVE varied from 0 to 12,658 VE/24 h (1916 ± 2649.9). Disappearance of VE during the baseline training session (DVET) correlated to DVE (P = 0.0319). BVE directly correlated to SDVE (P = 0.0008). Athletes' VE are highly variable over time, their variability depending on BVE, and they not infrequently tend to disappear. The only useful variable for predicting DVE is DVET.

Prevalence of HIV-1 integrase mutations related to resistance to dolutegravir in raltegravir naïve and pretreated patients.

The prevalence of HIV-1 integrase mutations related to resistance to the next-generation integrase inhibitor (INI), dolutegravir (DTG), was assessed in 440 INI-naïve subjects and in 120 patients failing a raltegravir (RTG)-containing regimen. Of the mutations selected by DTG in vitro, S153FY was not detected in any isolate while L101I and T124A were highly prevalent in both groups and significantly associated with non-B subtype. RTG-selected double and triple mutants, mostly the G140S/Q148H variant, were detected in only 32 (26.7%) RTG-treated patients. As L101I and T124A do not appear to exert any major effect in vivo and double and triple mutants resistant to DTG are infrequently selected by RTG, DTG can be effectively used in INI-naïve patients and may retain activity in many patients failing RTG.

Comparison of peginterferon pharmacokinetic and pharmacodynamic profiles.

The pharmacokinetics and in dosing regimens of the currently available pegylated interferon (peginterferon) alfa molecules differ greatly, depending on the size and nature of their polyethylene glycol (PEG) moiety. Peginterferon alfa-2a has a branched 40 kDa PEG chain covalently attached to lysine residues and circulates as an intact molecule. On the other hand, peginterferon alfa-2b has a linear 12 kDa PEG chain covalently attached to interferon-a-2b via an unstable urethane bond that is hydrolysed after injection, releasing native interferon alfa-2b. The difference in pegylation between the two peginterferons has a significant impact on their pharmacokinetic properties. Data from comparative and non-comparative studies indicate that peginterferon alfa-2b has a shorter half-life in serum than peginterferon alfa-2a, and a significant proportion of patients receiving peginterferon alfa-2b may have trough concentrations below the limit of detection during the latter part of the 7-day dosing schedule. However, the pharmacodynamic parameters of the two drugs appear to be similar.

Human immunodeficiency virus-1 B and non-B subtypes with the same drug resistance pattern respond similarly to antiretroviral therapy.

We analysed the 12-week virological response to protease inhibitor (PI) or non-nucleoside reverse transcriptase inhibitor (NNRTI) therapy in 1108 patients carrying B or non-B human immunodeficiency virus (HIV)-1 subtypes with matched resistance mutation patterns. Response rates were not significantly different for non-B and B subtypes stratified for treatment status (51.5% vs. 41.5% in naïve patients; 46.7% vs. 38.7% in experienced patients) or regimens (46.9% vs. 39.7% with PI; 56.7% vs. 40% with NNRTI). No difference in response was detected in patients harbouring B and non-B subtypes with any resistance profile. Further studies are advisable to fully test this approach on larger datasets.

Pharmacodynamics of peginterferon alpha-2a and peginterferon alpha-2b in interferon-naïve patients with chronic hepatitis C: a randomized, controlled study.

BACKGROUND: Peginterferon alpha-2a and alpha-2b, the two commercially available pegylated interferons, have different pharmacokinetic properties that produce differing abilities to suppress replication of the hepatitis C virus. AIM: To compare the pharmacodynamics of peginterferon alpha-2a and peginterferon alpha-2b in interferon-naive patients with chronic hepatitis C. METHODS: Patients were randomized to receive peginterferon alpha-2a, 180 microg (n = 10) or peginterferon alpha-2b 1.0 microg/kg (n = 12) once weekly. The enzymatic activity of 2'5'-oligoadenylate synthetase and levels of neopterin and beta(2)-microglobulin were measured at baseline and at 24, 48, 120 and 168 h. RESULTS: Oligoadenylate synthetase activity and serum neopterin and beta(2)-microglobulin concentrations did not differ significantly between the two patient groups at any time point, nor was there a significant correlation between the serum area under the concentration-time curve of either peginterferon and the area under the concentration-time curve for 2',5'-oligoadenylate synthetase, neopterin and beta(2)-microglobulin. The area under the concentration-time curves calculated for these three markers did not correlate with body mass index stratified at <25 and >or=25 kg/m(2) for either peginterferon. CONCLUSIONS: Despite pharmacokinetic differences between peginterferon alpha-2a and peginterferon alpha-2b, the pharmacodynamic profiles of the two formulations appear to be comparable.

Blastomyces dermatitidis of the perianal skin: report of a case.

Isolated fungal infections of the perianal skin are rare and their diagnosis is frequently overlooked. We report a case of a 78-year-old male patient who presented with a friable, violaceous, papulopustular lesion, with heaped-up edges along the anal verge. Biopsy revealed unicellular yeast consistent with blastomycosis. The patient was treated with itraconazole with resolution of this lesion. An extensive MEDLINE literature review from 1958 to the present indicates that this is an uncommon manifestation of cutaneous blastomycosis. A summary of the medical literature is presented with a review of the characteristics, diagnosis, and management of blastomycosis.

Key questions in antiretroviral therapy: Italian Consensus Workshop (2005).

A panel of leading Italian specialists in infectious diseases, virologists and immunologists met in Rome in 2005 to review critical data and discuss recommendations for each of the key questions in antiretroviral therapy today: When to start treatment? How to start? When to switch? What to switch to? Whether to stop or not to stop treatment, and how? The method of a nominal group meeting was used and recommendations were graded for their strength and quality using a system based on the one adopted by the Infectious Diseases Society of America. Main conclusions are summarized and critically discussed in this consensus statement, as well as some of the most recent data supporting these recommendations are provided.

Hepatotoxicity and antiretroviral therapy with protease inhibitors: A review.

Highly active antiretroviral therapy including protease inhibitors has led to dramatic decrease in the morbidity and mortality resulting from infection with human immunodeficiency virus-1. However, this combination regimen can be associated with the occurrence of serious toxicities, which may reduce patient compliance. In particular, human immunodeficiency virus-1 protease inhibitors and nevirapine among nonnucleoside reverse transcriptase inhibitors, have the potential for producing hepatotoxicity. We summarise current knowledge of the hepatotoxic effects associated with the commercially available human immunodeficiency virus-1 protease inhibitors based on a literature review of the major retrospective and prospective clinical studies designed to elucidate risk factors for developing hepatotoxicity among human immunodeficiency virus-1-infected patients receiving antiretroviral therapy containing protease inhibitors. Coinfection with chronic hepatitis, a common occurrence in human immunodeficiency virus-1-infected patients, is identified as an independent risk factor for developing hepatotoxicity in antiretroviral-treated human immunodeficiency virus-1-infected patients treated with antiretroviral regimens containing protease inhibitors. The importance of other risk factors for developing protease inhibitor-associated hepatotoxicity and the mechanism underlying the drug-related hepatotoxicity are discussed. The data indicate that the potential for producing hepatotoxicity is variable among the protease inhibitors and suggest that based on differences in drug-related hepatotoxicity, certain protease inhibitors may be preferred for the treatment of human immunodeficiency virus-hepatitis C virus coinfected patients.

Premature discontinuation of interferon plus ribavirin for adverse effects: a multicentre survey in 'real world' patients with chronic hepatitis C.

BACKGROUND: Interferon-alpha plus ribavirin therapy for chronic hepatitis C is associated with adverse effects that lead to therapy discontinuation in up to 27% of patients in randomized controlled trials. AIM: To examine the causes and predictive factors for therapy discontinuation in patients treated in current clinical practice. METHODS: We retrospectively enrolled 441 consecutive patients, scheduled to receive interferon-alpha + ribavirin for chronic hepatitis C, in five centres. Patients had been treated with 3 or 6 MU interferon-alpha three times a week plus ribavirin, 800-1200 mg daily, for 6 or 12 months. RESULTS: One hundred and eight [24.5%; confidence interval (CI), 20.5-28.8%] patients failed to finish combination therapy because of adverse events. The discontinuation rate was higher during the first 6 months of treatment; anaemia was an important cause (36.1% of discontinuations); unexplained lipothymia resulted in discontinuation in 11 patients. Female gender [hazard ratio (HR) = 1.85; CI, 1.17-2.92], an interferon-alpha dose > 15 MU/week (HR = 1.79; CI, 1.12-2.86) and no previous interferon-alpha treatment (HR = 1.63; CI, 1.04-2.57) were independent factors associated with discontinuation. The simultaneous presence of these factors identified patients at high risk for discontinuation [odds ratio (OR) = 10; CI, 3.98-25.13]. CONCLUSIONS: The study identified some predictive factors for adverse event-related discontinuation, which may improve the safety profile and effectiveness of interferon-alpha + ribavirin combination therapy in chronic hepatitis C.

Management of hepatitis C in human immunodeficiency virus-infected patients.

Hepatitis C virus-related liver disease and its associated complications are steadily emerging health concerns in persons co-infected with human immunodeficiency virus. The increasing number of liver-related deaths in human immunodeficiency virus-hepatitis C virus co-infected individuals supports the compelling argument for more aggressive treatment in these patients. The safety and efficacy of interferon/ribavirin in human immunodeficiency virus/hepatitis C virus co-infected patients is currently under evaluation. Despite well-documented concern over highly active antiretroviral therapy-associated hepatotoxicity human immunodeficiency virus/hepatitis C virus co-infected patients should be offered antiretroviral therapy. Since management of co-infected patients is complex a multidisciplinary approach is needed in order to facilitate care and help patients to achieve a positive outcome.

Comparison of the plasma pharmacokinetics of lamivudine during twice and once daily administration in patients with HIV.

OBJECTIVE: To compare the plasma pharmacokinetics of lamivudine 150mg twice daily and 300mg once daily in patients with HIV-1 infection. DESIGN: Nonblind, sequential, pharmacokinetic study. PARTICIPANTS: 13 patients with HIV-1 infection (median age 36 years). METHODS: Patients were tested during twice daily and then once daily regimens of lamivudine. In both regimens, the total daily dose of lamivudine was identical (300 mg/day). Blood samples for pharmacokinetic analysis were taken over a 12-hour period after > or =7 days of twice daily administration, and again over a 24-hour period after 7 days of once daily administration,. RESULTS: 12 patients completed the study. Lamivudine pharmacokinetic parameters (mean +/- SD) after administration of 150mg twice daily were: peak plasma concentration (Cmax) 2077+/-816 microg/L; trough plasma concentration (Cmin) 332+/-219 microg/L; elimination half-life (t 1/2beta) 6.1+/-1.9h; time to Cmax (t(max)) 1.6+/-0.7h; average concentration over the dosage interval (Cav) 711+/-269 microg/L; and area under the concentration-time curve (AUC) over 2 dosage intervals (24h) 17085+/-6464 microg x h/L. Corresponding values after administration of 300mg once daily were: Cmax 3461+/-854 microg/L; Cmin 146+/-87 microg/L; t1/2 7.9+/-3.4h; t(max) 2.2+/-1.3h; Cav 705+/-177 microg/L; and AUC over 1 dosage interval (24h) 16644+/-4150 microg x h/L. Statistical analysis showed a significant difference (p < 0.05) between the 2 schedules for Cmax and Cmin values, whereas no significant differences emerged for the other parameters. CONCLUSIONS: Once daily lamivudine leads to a similar exposure in plasma as twice daily administration of the same total daily dose. Since once daily administration may result in improved compliance, these results provide the pharmacokinetic basis for using lamivudine in a once daily regimen. Randomised clinical studies are needed to confirm this pharmacokinetic finding.

Acute abdominal symptoms in malignant hypertension: clinical presentation in five cases.

Malignant hypertension causes anatomical and functional damage in several target organs, in particular brain, retina, heart and kidneys. Although vascular lesions in the gastroenteric tract are known to occur in several instances, their clinical relevance is unknown. In this study five cases of malignant hypertension, presenting with acute abdominal symptoms, are reported. A history of essential arterial hypertension was present in three patients; while one patient had a previous diagnosis of renovascular hypertension and one patient had renoparenchymal hypertension. However, in all cases the antihypertensive treatment was discontinued and inadequate before the accelerated malignant phase. The acute abdominal symptoms at presentation were due to intestinal infarction in 3 patients and acute pancreatitis in 2 patients. One patient with intestinal infarction died of postoperative cardiogenic shock. Our data are in agreement with previous reports describing the possible intra-abdominal complications of malignant hypertension. The therapeutic approach in such conditions should always consider an effective antihypertensive treatment in conjunction with surgical options.

Human immunodeficiency virus type 1-related nucleic acids and papillomavirus DNA in cervicovaginal secretions of immunodeficiency virus-infected women.

OBJECTIVE: To evaluate simultaneous human immunodeficiency virus (HIV)-related nucleic acids and human papillomavirus (HPV)-DNA in cervicovaginal secretions of HIV-seropositive women. METHODS: We collected 47 paired blood and cervicovaginal lavage samples from 124 known HIV-1-seropositive women. Proviral HIV-1 DNA, cell-associated, and cell-free HIV-1 RNA in cervicovaginal secretions were quantitatively evaluated by competitive polymerase chain reaction (PCR) and reverse transcription PCR. Polymerase chain reaction and subsequent restriction fragment length polymorphism analysis of PCR products were used to detect HPV types 6, 11, 16, 18, 31, 33, 35, and 56. RESULTS: Proviral HIV-1 DNA, cell-associated, and cell-free HIV-1 RNA were detected in 52.4% (65 of 124), 38.7% (48 of 124), and 33.9% (42 of 124) of lavage samples, respectively. Human papillomavirus-DNA in cervicovaginal secretions was detected in 64% (79 of 124) of participants. The rate of detection of HPV types of intermediate to high oncogenic risk was higher in HIV-positive women who tested positive for cell-associated (odds ratio [OR] 3.57, 95% confidence interval [CI] 1.17, 11.12) or cell-free (OR 4.63, 95% CI 1.42, 15.51) HIV-1 RNA in cervicovaginal secretions than their counterparts who tested negative. Logistic regression analysis showed that the association between HPV infection and the detection of HIV-1 RNA in cervicovaginal secretions persisted after adjustment for potential confounders such as CD4+ cell counts, HIV-1 RNA in plasma, use of antiretroviral drugs, vaginal infection, and regular condom use. In univariable and multivariable analysis, HPV-DNA detection was associated with amounts of cell-free and cell-associated HIV-1 RNA in cervicovaginal secretions (chi(2) for trend 10.35, and 9.84, P =.001 and.002, respectively). CONCLUSIONS: The rate of HPV detection in the genital tract of HIV-1-seropositive women is associated with the amount of cell-associated and cell-free HIV-1 RNA present in cervicovaginal secretions. The association does not appear to be attributable entirely to the effect of HIV-related immunodepression.

Viral excretion in cervicovaginal secretions of HIV-1-infected women receiving antiretroviral therapy.

A longitudinal study was conducted to evaluate the viral shedding present in cervicovaginal secretions of HIV-1-seropositive women receiving antiretroviral therapy. A total of 128 paired cervicovaginal and blood samples was obtained from 37 women during a median follow-up period of 21 months. A sensitive, competitive, polymerase chain reaction and a reverse transcription polymerase chain reaction were used for the simultaneous quantitation of HIV-1 proviral DNA and RNA in cervicovaginal cells and cell-free RNA in cervicovaginal secretions, as well as HIV-1 RNA in peripheral blood. The cumulative probability of detecting proviral DNA in genital secretions was significantly higher over time in women with detectable viremia than in women in whom HIV-1 RNA was persistently undetectable in plasma (< 50 copies/ml) (P = 0.028 by log-rank test). The presence and amount of proviral DNA, cell-associated RNA and cell-free RNA in the cervicovaginal secretions were positively correlated with the presence of detectable viremia or the number of HIV-1 RNA copies in plasma (Spearman rank correlation, 0.290, 0.279, and 0.305, respectively; all P < 0.01), but no correlation was found with the CD4+ cell count. In addition, vaginal infections were positively correlated with the detection of proviral DNA in cervicovaginal secretions (odds ratio, 2.60; 95% confidence interval, 1.07-5.70). However, the positive correlation between the presence and amount of HIV in cervicovaginal secretions and the viral load in plasma provides no assurance that HIV shedding does not occur in the genital tract of women with undetectable HIV-RNA in plasma.