Current features of infective endocarditis in persons on hemodialysis: a prevalence study with case control design from the prospective multicenter SEI cohort.

PURPOSE: Persons on hemodialysis (HD) are at high risk of infective endocarditis (IE). In non-comparative retrospective studies, a higher rate of mortality was reported in IE on HD. We assessed risk factors, clinical characteristics, and outcomes of IE in HD. METHODS: This was a prevalence study with a case control methodology on a set of data from the prospectively followed cohort of the Studio Endocarditi Italiano (SEI), conducted between 2004 and 2011. Included were 42 consecutive cases of IE HD subjects and 126 controls not on HD, matched for age, sex, type of IE, and heart side involved. Clinical, echocardiographic, microbiological features, and disease complications and therapeutic modalities were assessed. RESULTS: HD patients were more often diabetics (42.9 vs 18.2 % in no-HD; p = 0.007) and immune-suppressed (16.7 vs 3.2 %; p = 0.02), and had a higher rate of predisposing cardiac conditions (45 vs 25 %; p = 0.031). A higher prevalence of health care-related acquisition and a shorter diagnostic delay was observed in IE on HD, that was more likely to be caused by staphylococci and less by streptococci (p < 0.002). Cardiac surgery was performed in 38 % of HD patients and 36.5 % of no-HD patients (p = 0.856). Complications were similar and in-hospital mortality did not differ significantly (26.2 % in HD vs 15.9 % in no-HD; p = 0.168). CONCLUSIONS: IE in persons on HD is characterized by distinctive clinical features, including a higher prevalence of some important comorbidities. Inconsistent with prior studies, we could not confirm a higher rate of complications and mortality in HD patients with IE.

Association between valvular surgery and mortality among patients with infective endocarditis complicated by heart failure.

CONTEXT: Heart failure (HF) is the most common complication of infective endocarditis. However, clinical characteristics of HF in patients with infective endocarditis, use of surgical therapy, and their associations with patient outcome are not well described. OBJECTIVES: To determine the clinical, echocardiographic, and microbiological variables associated with HF in patients with definite infective endocarditis and to examine variables independently associated with in-hospital and 1-year mortality for patients with infective endocarditis and HF, including the use and association of surgery with outcome. DESIGN, SETTING, AND PATIENTS: The International Collaboration on Endocarditis-Prospective Cohort Study, a prospective, multicenter study enrolling 4166 patients with definite native- or prosthetic-valve infective endocarditis from 61 centers in 28 countries between June 2000 and December 2006. MAIN OUTCOME MEASURES: In-hospital and 1-year mortality. RESULTS: Of 4075 patients with infective endocarditis and known HF status enrolled, 1359 (33.4% [95% CI, 31.9%-34.8%]) had HF, and 906 (66.7% [95% CI, 64.2%-69.2%]) were classified as having New York Heart Association class III or IV symptom status. Within the subset with HF, 839 (61.7% [95% CI, 59.2%-64.3%]) underwent valvular surgery during the index hospitalization. In-hospital mortality was 29.7% (95% CI, 27.2%-32.1%) for the entire HF cohort, with lower mortality observed in patients undergoing valvular surgery compared with medical therapy alone (20.6% [95% CI, 17.9%-23.4%] vs 44.8% [95% CI, 40.4%-49.0%], respectively; P < .001). One-year mortality was 29.1% (95% CI, 26.0%-32.2%) in patients undergoing valvular surgery vs 58.4% (95% CI, 54.1%-62.6%) in those not undergoing surgery (P < .001). Cox proportional hazards modeling with propensity score adjustment for surgery showed that advanced age, diabetes mellitus, health care-associated infection, causative microorganism (Staphylococcus aureus or fungi), severe HF (New York Heart Association class III or IV), stroke, and paravalvular complications were independently associated with 1-year mortality, whereas valvular surgery during the initial hospitalization was associated with lower mortality. CONCLUSION: In this cohort of patients with infective endocarditis complicated by HF, severity of HF was strongly associated with surgical therapy and subsequent mortality, whereas valvular surgery was associated with lower in-hospital and 1-year mortality.

Heterogeneous vancomycin-intermediate susceptibility phenotype in bloodstream methicillin-resistant Staphylococcus aureus isolates from an international cohort of patients with infective endocarditis: prevalence, genotype, and clinical significance.

BACKGROUND: The significance of heterogeneous vancomycin-intermediate Staphylococcus aureus (hVISA) is unknown. Using a multinational collection of isolates from methicillin-resistant S. aureus (MRSA) infective endocarditis (IE), we characterized patients with IE with and without hVISA, and we genotyped the infecting strains. METHODS: MRSA bloodstream isolates from 65 patients with definite IE from 8 countries underwent polymerase chain reaction (PCR) for 31 virulence genes, pulsed-field gel electrophoresis, and multilocus sequence typing. hVISA was defined using population analysis profiling. RESULTS: Nineteen (29.2%) of 65 MRSA IE isolates exhibited the hVISA phenotype by population analysis profiling. Isolates from Oceania and Europe were more likely to exhibit the hVISA phenotype than isolates from the United States (77.8% and 35.0% vs 13.9%; P < .001). The prevalence of hVISA was higher among isolates with a vancomycin minimum inhibitory concentration of 2 mg/L (P = .026). hVISA-infected patients were more likely to have persistent bacteremia (68.4% vs 37.0%; P = .029) and heart failure (47.4% vs 19.6%; P = .033). Mortality did not differ between hVISA- and non-hVISA-infected patients (42.1% vs 34.8%, P = .586). hVISA and non-hVISA isolates were genotypically similar. CONCLUSIONS: In these analyses, the hVISA phenotype occurred in more than one-quarter of MRSA IE isolates, was associated with certain IE complications, and varied in frequency by geographic region.

Phylogenetic analysis of viridans group streptococci causing endocarditis.

Identification of viridans group streptococci (VGS) to the species level is difficult because VGS exchange genetic material. We performed multilocus DNA target sequencing to assess phylogenetic concordance of VGS for a well-defined clinical syndrome. The hierarchy of sequence data was often discordant, underscoring the importance of establishing biological relevance for finer phylogenetic distinctions.

Infection of intravascular prostheses: how to treat other than surgery.

Long-term antimicrobial therapy may be effective in some patients with intravascular prosthesis infection. However, this approach does not represent an alternative to surgery when this is feasible, but is merely the best opportunity for patients too ill to tolerate a re-intervention. Prosthetic valve endocarditis may be treated with antibiotic therapy alone in selected patients who are haemodynamically stable with non-staphylococcal infections and no para-valvular complications. In contrast, infections of pacemaker leads or other implantable cardiac devices require complete hardware removal, as infection recurrence always occurs, even after a seemingly effective initial treatment. Attempts to treat conservatively infections of abdominal aortic grafts can be successful in a few cases, provided the patient is stable, the pathogen has been identified, and antibiotic susceptibility has been demonstrated. Treatment requires at least 4-6 weeks and may be followed by a sequential oral regimen once the acute phase of the infection has subsided. The correct duration of this treatment is often unknown and relapses are common after treatment withdrawal. The availability of novel antibacterial and antifungal agents - showing fast microbicidal activity that includes biofilm micro-organisms - such as daptomycin and caspofungin, or having a wide antimicrobial spectrum, such as tigecycline, may increase the probability of long-standing suppression or even eradication of the infection in these particular subsets of inoperable patients. However, so far, very little experience is available on the efficacy and tolerability of these drugs in intravascular prosthesis infections. Controlled studies are lacking and difficult to plan. Well-designed prospective studies may help to establish guidelines and reach a multidisciplinary consensus on the optimal therapeutic approach, and are therefore awaited.

Comparative activities of colistin, rifampicin, imipenem and sulbactam/ampicillin alone or in combination against epidemic multidrug-resistant Acinetobacter baumannii isolates producing OXA-58 carbapenemases.

This study evaluated the activity of colistin, rifampicin, imipenem and sulbactam/ampicillin alone or in combination against nine epidemic multidrug-resistant Acinetobacter baumannii isolates producing OXA-58 carbapenemase in Naples, Italy. The isolates were susceptible to colistin but differed in their resistance to imipenem and rifampicin. Time-kill studies showed a bactericidal effect for colistin but not for imipenem, rifampicin or sulbactam/ampicillin used as single agents. Synergism was observed with combinations of rifampicin+imipenem or sulbactam/ampicillin for all isolates and with colistin+rifampicin for isolates showing higher minimum inhibitory concentrations for rifampicin. Combined use of the antimicrobials tested may provide good therapeutic options for OXA-58 carbapenemase-producing A. baumannii infections.

Liver biopsy in type 2 diabetes mellitus: Steatohepatitis represents the sole feature of liver damage.

Recent studies report a prevalence of non-alcoholic fatty liver disease (NAFLD) of between 70% and 80% in patients with metabolic syndrome (MS) and type 2 diabetes mellitus (T2DM). Nevertheless, it is not possible to differentiate between simple steatosis and non-alcoholic steatohepatitis (NASH) with non-invasive tests. The aim of this study was to differentiate between simple steatosis and NASH by liver biopsy in patients with hypertransaminasemia and MS or T2DM. Two hundred and fifteen patients with increased ALT levels and MS, and 136 patients at their first diagnosis of T2DM regardless of ALT values were consecutively admitted to a tertiary hepatology center between January 2004 and November 2014. Exclusion criteria were other causes of liver disease/ALT increase. Each patient underwent a clinical, laboratory and ultrasound evaluation, and a liver biopsy. Gender distribution, age, and body mass index were similar in the two groups of patients, whereas cholesterol levels, glycemia and blood pressure were significantly different between the two groups. The prevalence of NAFLD was 94.82% in MS patients and 100% in T2DM patients. NASH was present in 58.52% of MS patients and 96.82% of T2DM. Consequently, this study reveals that, by using liver biopsy, almost all patients with T2DM or MS have NAFLD, which in patients with T2DM means NASH. Importantly, it suggests that NASH may be one of the early complications of T2DM due to its pathophysiological correlation with insulin resistance.

Risk factors for "major" embolic events in hospitalized patients with infective endocarditis.

BACKGROUND: Infective endocarditis often is complicated by embolic events after hospital admission. Identifying patients at higher risk may improve the disease outcome. This study was aimed at identifying predictors of embolic risk among the clinical and laboratory data obtained on hospital admission in patients diagnosed as having definite infective endocarditis according to the Duke criteria. METHODS: Ninety-four patients were enrolled in a prospective study. The results of hematologic, echocardiographic, and microbiological investigations were analyzed, using statistical methods as appropriate. Multivariate analysis was applied to variables significantly associated with embolism in univariate analysis. RESULTS: Forty-six percent of patients had a major embolic complication after admission. No association was found between embolism and sex, site of infection, or microorganism involved. Patients with embolism were significantly younger, had larger vegetation, and showed a significantly higher level of serum C-reactive protein and lower albumin concentrations than those without embolism. Young age, larger vegetation size, and high levels of C-reactive protein were the independent variables associated with an increased incidence of embolic events in the multivariate logistic regression analysis. CONCLUSIONS: Our data indicate that patients with infective endocarditis with young age and/or with large vegetation and/or with high serum levels of C-reactive protein are at increased risk of major embolic complications during the in-hospital course of the disease.

Current trends in the management of cardiac implantable electronic device (CIED) infections.

Cardiac implantable electronic device (CIED) infections are an emerging clinical problem. A growing number of dedicated and high quality clinical studies are currently being generated. We here review the most recent advances in the diagnosis and treatment of patients with CIED infection including intracardiac lead endocarditis. We discuss the current etiology and risk factors, and appraise the major diagnostic issues, describing our center's therapeutic approach. We also address the management of CIED infection complications.

In-hospital and 1-year mortality in patients undergoing early surgery for prosthetic valve endocarditis.

IMPORTANCE: There are limited prospective, controlled data evaluating survival in patients receiving early surgery vs medical therapy for prosthetic valve endocarditis (PVE). OBJECTIVE: To determine the in-hospital and 1-year mortality in patients with PVE who undergo valve replacement during index hospitalization compared with patients who receive medical therapy alone, after controlling for survival and treatment selection bias. DESIGN, SETTING, AND PARTICIPANTS: Participants were enrolled between June 2000 and December 2006 in the International Collaboration on Endocarditis-Prospective Cohort Study (ICE-PCS), a prospective, multinational, observational cohort of patients with infective endocarditis. Patients hospitalized with definite right- or left-sided PVE were included in the analysis. We evaluated the effect of treatment assignment on mortality, after adjusting for biases using a Cox proportional hazards model that included inverse probability of treatment weighting and surgery as a time-dependent covariate. The cohort was stratified by probability (propensity) for surgery, and outcomes were compared between the treatment groups within each stratum. INTERVENTIONS: Valve replacement during index hospitalization (early surgery) vs medical therapy. MAIN OUTCOMES AND MEASURES: In-hospital and 1-year mortality. RESULTS: Of the 1025 patients with PVE, 490 patients (47.8%) underwent early surgery and 535 individuals (52.2%) received medical therapy alone. Compared with medical therapy, early surgery was associated with lower in-hospital mortality in the unadjusted analysis and after controlling for treatment selection bias (in-hospital mortality: hazard ratio [HR], 0.44 [95% CI, 0.38-0.52] and lower 1-year mortality: HR, 0.57 [95% CI, 0.49-0.67]). The lower mortality associated with surgery did not persist after adjustment for survivor bias (in-hospital mortality: HR, 0.90 [95% CI, 0.76-1.07] and 1-year mortality: HR, 1.04 [95% CI, 0.89-1.23]). Subgroup analysis indicated a lower in-hospital mortality with early surgery in the highest surgical propensity quintile (21.2% vs 37.5%; P = .03). At 1-year follow-up, the reduced mortality with surgery was observed in the fourth (24.8% vs 42.9%; P = .007) and fifth (27.9% vs 50.0%; P = .007) quintiles of surgical propensity. CONCLUSIONS AND RELEVANCE: Prosthetic valve endocarditis remains associated with a high 1-year mortality rate. After adjustment for differences in clinical characteristics and survival bias, early valve replacement was not associated with lower mortality compared with medical therapy in the overall cohort. Further studies are needed to define the effect and timing of surgery in patients with PVE who have indications for surgery.

Molecular epidemiology and mechanisms of rifampicin resistance in Acinetobacter baumannii isolates from Italy.

Use of rifampicin (RIF) in combination with colistin (COL) has been proposed for the treatment of multidrug-resistant Acinetobacter baumannii infections owing to in vitro synergism. The aim of the present study was to evaluate the molecular epidemiology and mechanisms of RIF resistance in 57 clinical isolates of A. baumannii in two tertiary care hospitals in Naples (Italy) from 2006 to 2010. Amongst the collection, 36 isolates showed high RIF minimum inhibitory concentrations (MICs) (256 mg/L to ≥512 mg/L), 16 showed intermediate MICs (8-16 mg/L) and 5 had low MICs (4 mg/L). Of the 36 isolates with elevated RIF MICs, 35 were assigned to sequence type ST2 and 1 to ST78. Amongst the 57 isolates, 35 carried at least one mutation in rpoB, including H535L in 9 isolates and double mutations D525N and P544L in 7 isolates, whilst 22 showed no rpoB mutations. Treatment with the efflux pump inhibitor phenyl-arginine-ß-naphthylamide (PAßN) of resistant isolates with no mutations in rpoB and different RIF MICs reduced the MIC by >10-fold and restored the synergism between RIF and COL in time-kill studies, whilst it had no effect on strains carrying rpoB mutations. In conclusion, the emergence of elevated RIF MICs in A. baumannii isolates from our geographical area was mostly caused by mutations in rpoB; low to intermediate RIF MICs were also caused by altered membrane permeability to the drug. The phenomenon was contributed by the selection of two prevalent clones both assigned to ST2 genotype. These data may have implications for the correct identification of cases with A. baumannii infection that would not benefit from addition of RIF to COL.

Management of Gram-negative and fungal endocarditis.

Infective endocarditis is infrequently caused by Gram-negative bacteria or fungi. Gram-negative organisms are responsible for <4% of cases, whilst fungal endocarditis accounts for <1.5% of culture-positive cases worldwide. Endocarditis due to Gram-negative organisms or fungi is a rare but severe disease. It often has a nosocomial origin, is caused by virulent and often resistant organisms and presents a high rate of complications and high mortality. In this article we present the most recent literature data and address the current management of Gram-negative and fungal infective endocarditis. We also discuss the major challenges of antimicrobial treatment and discuss some issues related to surgical decision-making in difficult-to-manage cases. We finally present our centre's experience with Gram-negative infective endocarditis, with a special focus on the demanding issues that the management of these complex and severely ill patients raise.

Leukocyte interferon-alpha and ribavirin for treatment of chronic hepatitis C patients intolerant to pegylated-interferon.

Treatments for chronic hepatitis C (CHC) patients intolerant to pegylated interferons (peg-IFNs) are lacking. Thus, such patients remain at high risk of developing an advanced and decompensated liver disease. Leukocyte IFN-alpha (Le-IFN-alpha) seems to possess a safer profile than other natural and recombinant a-interferons, but no information is available for peg-IFN intolerant patients. Accordingly, we evaluated the safety and efficacy of Le-IFN-alpha in patients intolerant to peg-IFNs. Twenty-five consecutive CHC patients intolerant to peg-IFNs were prospectively enrolled. HCV genotype 1 was present in 80% and cirrhosis in 68% of cases. Thirteen patients (52%) had thrombocytopenia. Le-IFN-alpha (3 MU three times a week) was administered for 48 weeks plus ribavirin 800 or 1,000 mg/day for HCV genotype 2/3 and 1, respectively. The follow-up was at 24 weeks. Compliance with treatment was satisfactory if the patient received 80% of the therapeutic regimen. An intention-to-treat analysis was done. Eighty-eight percent of CHC patients completed the prescribed treatment course with Le-IFN-alpha. In these patients the side effects, when observed, were mild to moderate, and did not require Le-IFN-alpha dose adjustment. Le-IFN-alpha showed significantly less hematological toxicity than peg-IFN (4 vs 48%; P<0.02). The overall sustained virologic response was 32%, i.e., 24% for cirrhotics and 50% for CHC, and 25% for genotype 1 and 60% for genotypes 2/3. The data indicate that Le-IFN-alpha plus ribavirin is a useful and effective treatment for CHC patients who are intolerant to peg-IFNs.

Clinical presentation, etiology, and outcome of infective endocarditis in the 21st century: the International Collaboration on Endocarditis-Prospective Cohort Study.

BACKGROUND: We sought to provide a contemporary picture of the presentation, etiology, and outcome of infective endocarditis (IE) in a large patient cohort from multiple locations worldwide. METHODS: Prospective cohort study of 2781 adults with definite IE who were admitted to 58 hospitals in 25 countries from June 1, 2000, through September 1, 2005. RESULTS: The median age of the cohort was 57.9 (interquartile range, 43.2-71.8) years, and 72.1% had native valve IE. Most patients (77.0%) presented early in the disease (<30 days) with few of the classic clinical hallmarks of IE. Recent health care exposure was found in one-quarter of patients. Staphylococcus aureus was the most common pathogen (31.2%). The mitral (41.1%) and aortic (37.6%) valves were infected most commonly. The following complications were common: stroke (16.9%), embolization other than stroke (22.6%), heart failure (32.3%), and intracardiac abscess (14.4%). Surgical therapy was common (48.2%), and in-hospital mortality remained high (17.7%). Prosthetic valve involvement (odds ratio, 1.47; 95% confidence interval, 1.13-1.90), increasing age (1.30; 1.17-1.46 per 10-year interval), pulmonary edema (1.79; 1.39-2.30), S aureus infection (1.54; 1.14-2.08), coagulase-negative staphylococcal infection (1.50; 1.07-2.10), mitral valve vegetation (1.34; 1.06-1.68), and paravalvular complications (2.25; 1.64-3.09) were associated with an increased risk of in-hospital death, whereas viridans streptococcal infection (0.52; 0.33-0.81) and surgery (0.61; 0.44-0.83) were associated with a decreased risk. CONCLUSIONS: In the early 21st century, IE is more often an acute disease, characterized by a high rate of S aureus infection. Mortality remains relatively high.

Interplay between oxidative stress and hepatic steatosis in the progression of chronic hepatitis C.

BACKGROUND/AIMS: The contribution of oxidative stress to the pathogenesis of chronic hepatitis C (CHC) is still poorly elucidated. This study investigated the relationship between oxidative stress, insulin resistance, steatosis and fibrosis in CHC. METHODS: IgG against malondialdehyde-albumin adducts and HOMA-IR were measured as markers of oxidative stress and insulin resistance, respectively, in 107 consecutive CHC patients. RESULTS: Oxidative stress was present in 61% of the patients, irrespective of age, gender, viral load, BMI, aminotransferase level, histology activity index (HAI) and HCV genotype. Insulin resistance and steatosis were evident in 80% and 70% of the patients, respectively. In the patients infected by HCV genotype non-3, but not in those with genotype 3 infection HOMA-IR (p<0.03), steatosis (p=0.02) and fibrosis (p<0.05) were higher in the subjects with oxidative stress than in those without. Multiple regression analysis revealed that, HOMA-IR (p<0.01), fibrosis (p<0.01) and oxidative stress (p<0.05) were independently associated with steatosis, whereas steatosis was independently associated with oxidative stress (p<0.03) and HOMA-IR (p<0.02). Steatosis (p<0.02) and HAI (p=0.007) were also independent predictors of fibrosis. CONCLUSIONS: In patients infected by HCV genotype non-3, oxidative stress and insulin resistance contribute to steatosis, which in turn exacerbates both insulin resistance and oxidative stress and accelerates the progression of fibrosis.

Current features of infective endocarditis in elderly patients: results of the International Collaboration on Endocarditis Prospective Cohort Study.

BACKGROUND: Elderly patients are emerging as a population at high risk for infective endocarditis (IE). However, adequately sized prospective studies on the features of IE in elderly patients are lacking. METHODS: In this multinational, prospective, observational cohort study within the International Collaboration on Endocarditis, 2759 consecutive patients were enrolled from June 15, 2000, to December 1, 2005; 1056 patients with IE 65 years or older were compared with 1703 patients younger than 65 years. Risk factors, predisposing conditions, origin, clinical features, course, and outcome of IE were comprehensively analyzed. RESULTS: Elderly patients reported more frequently a hospitalization or an invasive procedure before IE onset. Diabetes mellitus and genitourinary and gastrointestinal cancer were the major predisposing conditions. Blood culture yield was higher among elderly patients with IE. The leading causative organism was Staphylococcus aureus, with a higher rate of methicillin resistance. Streptococcus bovis and enterococci were also significantly more prevalent. The clinical presentation of elderly patients with IE was remarkable for lower rates of embolism, immune-mediated phenomena, or septic complications. At both echocardiography and surgery, fewer vegetations and more abscesses were found, and the gain in the diagnostic yield of transesophageal echocardiography was significantly larger. Significantly fewer elderly patients underwent cardiac surgery (38.9% vs 53.5%; P < .001). Elderly patients with IE showed a higher rate of in-hospital death (24.9% vs 12.8%; P < .001), and age older than 65 years was an independent predictor of mortality. CONCLUSIONS: In this large prospective study, increasing age emerges as a major determinant of the clinical characteristics of IE. Lower rates of surgical treatment and high mortality are the most prominent features of elderly patients with IE. Efforts should be made to prevent health care-associated acquisition and improve outcomes in this major subgroup of patients with IE.

Nocardia brasiliensis in Italy: a nine-year experience.

In the past, no case reports concerning N. brasiliensis infections were published from Italy. We now report 4 cases observed during 1998-2006 in 4 Italian patients, 1 immunosuppressed and 3 immunocompetent.

Molecular epidemiology of high-level aminoglycoside-resistant enterococci isolated from patients in a university hospital in southern Italy.

OBJECTIVES: We evaluated the genetic and molecular basis of high-level resistance to gentamicin and amikacin in 91 clinical isolates of Enterococcus faecalis and Enterococcus faecium in a university hospital in southern Italy from 1987 to 2003. METHODS: Antibiotic susceptibility was evaluated by disc diffusion and microdilution methods. Genotyping was performed by PFGE and dendrogram analysis. Aminoglycoside resistance genes were analysed by multiplex PCR. Aminoglycoside resistance gene transfer was performed by filter mating. RESULTS: In our strain collection, 44% of E. faecalis and 52% of E. faecium were high-level-resistant to gentamicin. Fifty-two PFGE profiles were identified for E. faecalis and 15 for E. faecium. Although the majority of PFGE patterns were single isolates, four patterns (two for E. faecalis and two for E. faecium) were isolated each in 8 and 4, and 6 and 4 different patients, respectively. The aac(6')-Ie-aph(2'')-Ia gene was responsible for high-level resistance to gentamicin and amikacin in E. faecalis and E. faecium; the aph(2'')-Id gene responsible for resistance to gentamicin was also isolated in E. faecium; the aph(3')-IIIa and ant(4')-Ia genes responsible for resistance to amikacin were also isolated in E. faecalis and E. faecium. High-level resistance to gentamicin, along with the aac(6')-Ie-aph(2'')-Ia gene, was transferred at a frequency of about 10(-5) to 10(-8) per recipient cell in 14 of 17 E. faecalis and 3 of 4 E. faecium different genotypes. CONCLUSIONS: The spread of the aac(6')-Ie-aph(2'')-Ia gene was responsible for high-level resistance to gentamicin and amikacin among enterococci isolated from patients in our geographical area.

Anti-envelope 1 and 2 immune response in chronic hepatitis C patients: effects of hepatitis B virus co-infection and interferon treatment.

Antibodies against envelope glycoprotein 1 and 2 (anti-E1/E2) have been suggested to influence HCV replication levels. Hepatitis B virus (HBV) may interfere with hepatitis C virus (HCV) replication. At present there are no data on anti-E1/E2 antibody responses or on the effect of interferon (IFN) treatment in HBV-HCV co-infection. Accordingly, we evaluated serum anti-E1/E2 antibodies in 50 patients (median age, 26.5; males, 30) with chronic hepatitis, 38 with HCV and 12 with HBV-HCV co-infection, who had undergone alpha-IFN treatment. Before starting IFN, the HCV group showed higher HCV-RNA levels (bDNA assay) than the HBV-HCV group (median 3.75 vs. 0.64 x 10(6) Eq/ml, respectively; P < 0.05). Similarly, the anti-E2 levels (EIA assay) were higher in the HCV group than in the HBV-HCV (mean +/- SD, 53.8 +/- 54.58 vs. 24.5 +/- 41.50 U/ml, respectively; P < 0.02), and the prevalence of anti-E2 was also higher in the HCV group (94 vs. 58%, respectively; P < 0.007). No correlation was found between anti-E1/E2 antibodies and the HCV-RNA levels. The prevalence of E1/E2 antibodies was similar in the different HCV genotypes. Higher baseline levels of anti-E2 antibodies and a decrease or disappearance of anti-E2 antibodies during IFN were associated with IFN sustained response in both groups, whereas no reduction in the anti-E1/E2 levels was observed in non-responders. The data show that HBV co-infection influences both HCV replication and the anti-E1/E2 antibody production. High pre-treatment levels of anti-E2 antibodies and their decrease or disappearance during interferon treatment are often associated with HCV clearance in sustained responders, irrespective of the HCV genotype.