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Objective: Some patients with chronic hepatitis C virus (HCV) infection fail to achieve complete early virologic response (EVR) despite a marked decrease in HCV RNA at 4 weeks. We investigated the characteristics and final treatment outcomes of this patient subpopulation. Methods: A total of 516 patients with HCV genotype 1 were enrolled. Background characteristics and final outcomes were compared between patients who achieved complete EVR and those who did not among patients whose HCV RNA levels decreased 3.0 log10 or more at 4 weeks. Results: 78 of 334 patients (23.4%) with a ≥3.0 log10 reduction in HCV RNA levels at 4 weeks failed to achieve complete EVR. Female sex, higher pretreatment HCV RNA levels and lower baseline alanine aminotransferase (ALT) activity were independently associated with failure of complete EVR. The rate of sustained virologic response (SVR) in patients without complete EVR was 47.4%, significantly lower than that in patients with complete EVR (89.7%, p < 0.0001). Conclusions: Female patients, patients with higher pretreatment HCV RNA levels and patients with lower baseline ALT have a high likelihood of failure of complete EVR even when they had a ≥3 log10 reduction of HCV RNA at 4 weeks, resulting in a significantly lower SVR rate.

The rapid diagnosis of pathogens and prompt initiation of appropriate antibiotic therapy are critical factors to reduce the morbidity and mortality associated with sepsis. In this study, we evaluated a multiplex polymerase chain reaction (PCR-M) test that detects bacteria and fungi in whole-blood specimens, comparing its features to those of a blood culture (BC). Following evaluation of the performance for sensitivity and specificity of PCR-M, 78 blood samples from 54 patients with suspected bacterial infections were evaluated. Whole-blood samples for PCR-M were collected at the same time as BC, and PCR-M results were compared with BC results. As a result, minimum sensitivity of the kit was 1-100 cfu/ml. The PCR-M test correctly identified specificity for 13 out of 14 strains blinded to the assay analyst. Of 78 blood samples examined, 56 (72%) were negative by both methods, and 22 (28%) were positive by at least one of the two methods. PCR-M detected organisms in 21 cases (27%) compared with 12 cases (15%) in BC. The correlation of positives between PCR-M and BC was 92% (11/12), and both methods identified the same organisms in these 11 cases. With higher positive rate compared with BC, PCR-M could detect and identify potentially significant microorganisms within a few hours by using a small volume of a single whole-blood sample. Early detection of microorganisms has the potential to facilitate early determination of appropriate treatment and antimicrobial selection.

The DNA binding domain of H-NS protein was studied with various N-terminal deletion mutant proteins and identified by gel retardation assay and heteronuclear 2D- and 3D-NMR spectroscopies. It was shown from gel retardation assay that DNA binding affinity of the mutant proteins relative to that of native H-NS falls in the range from 1/6 to 1/25 for H-NS(60-137), H-NS(70-137) and H-NS(80-137), whereas it was much weaker for H-NS(91-137). Thus, the DNA binding domain was defined to be the region from residue A80 to the C-terminus. Sequential nuclear Overhauser effect (NOE) connectivities and those of medium ranges revealed that the region of residues Q60-R93 in mutant protein H-NS(60-137) forms a long stretch of disordered, flexible chain, and also showed that the structure of the C-terminal region (residues A95-Q137) in mutant H-NS(60-137) was nearly identical to that of H-NS(91-137). 1H and 15N chemical shift perturbations induced by complex formation of H-NS(60-137) with an oligonucleotide duplex 14-mer demonstrated that two loop regions, i.e. residues A80-K96 and T110-A117, play an essential role in DNA binding.

Background The importance of the reduction in hepatitis C virus (HCV) RNA levels 4 and 12 weeks after starting peginterferon (PEG-IFN) and ribavirin combination therapy has been reported to predict a sustained virologic response (SVR) in patients infected with HCV genotype 1. We conducted a multicenter study to validate this importance along with baseline predictive factors in this patient subpopulation. Methods A total of 516 patients with HCV genotype 1 and pretreatment HCV RNA levels ≥5.0 log10 IU/mL who completed response-guided therapy according to the AASLD guidelines were enrolled. The reduction in serum HCV RNA levels 4 and 12 weeks after starting therapy was measured using real-time PCR, and its value in predicting the likelihood of SVR was evaluated. Results The area under the receiver operating characteristics (ROC) curve was 0.852 for 4-week reduction and 0.826 for 12-week reduction of HCV RNA levels, respectively. When the cut-off is fixed at a 2.8-log10 reduction at 4 weeks and a 4.9-log10 reduction at 12 weeks on the basis of ROC analysis, the sensitivity and specificity for SVR were 80.9% and 77.9% at 4 weeks and were 89.0% and 67.2% at 12 weeks, respectively. These variables were independent factors associated with SVR in multivariate analysis. Among 99 patients who showed a delayed virologic response and completed 72-week extended regimen, the area under ROC curve was low: 0.516 for 4-week reduction and 0.482 for 12-week reduction of HCV RNA levels, respectively. Conclusions The reduction in HCV RNA levels 4 and 12 weeks after starting combination therapy is a strong independent predictor for SVR overall. These variables were not useful for predicting SVR in patients who showed a slow virologic response and experienced 72-week extended regimen.

Both baseline predictive factors and viral response at week 4 of therapy are reported to have high predictive ability for sustained virologic response to peginterferon and ribavirin combination therapy in patients with hepatitis C virus (HCV) genotype 1. However, it is not clear how these baseline variables and week 4 response should be combined to predict sustained virologic response. In this multicenter study, the authors investigated the impact of baseline predictive factors on the predictive value of week 4 viral response. Receiver-operating characteristic curve analyses were performed to evaluate the ability of week 4 reduction in HCV RNA levels to predict sustained virologic response in 293 Japanese patients infected with HCV genotype 1b. Analyses were performed in all patients and in patient subgroups stratified according to baseline variables. Overall, week 4 viral reduction demonstrates a high predictive ability for sustained virologic response. The sensitivity, specificity, positive predictive value (PPV), negative predictive value, and accuracy were higher than those of viral reduction at week 12. However, the best cut-off levels differ depending on the baseline factors and they were lower in patients with unfavorable baseline predictors. When patients had the TG/GG rs8099917 genotype, the best cut-off was markedly low with low PPV. Week 4 viral response can be a predictor of sustained virologic response in patients with HCV genotype 1 and is better than week 12 viral response. However, the cut-off levels should be modified based on the baseline predictive variables. J. Med. Virol. 85:65–70, 2012. © 2012 Wiley Periodicals, Inc.

Treatment for chronic hepatitis B has improved drastically with the use of nucleot(s)ide analogues (NAs). However, NA therapy typically fails to eliminate Hepatitis B virus (HBV) completely, and it is difficult to discontinue these therapies. We previously demonstrated that NA therapy induced immature viral particles, including HBV RNA in sera of chronic hepatitis B patients. In the study reported here, we analyzed the association between HBV RNA titer and the recurrence rate of hepatitis after discontinuation of NA therapy.The study cohort comprised 36 patients who had discontinued NA therapy. Serum HBV DNA or DNA plus RNA levels were measured by real time PCR and statistical analyses were performed using clinical data and HBV markers.At 24 weeks after discontinuation of NA therapy, HBV DNA rebound was observed in 19 of the 36 patients (52.8 %), and alanine aminotransferase (ALT) rebound was observed in 12 of 36 patients (33.3 %). Multivariate statistical analysis was used to identify factors predictive of HBV DNA rebound. The HBV DNA + RNA titer following 3 months of treatment was significantly associated with HBV DNA rebound [P = 0.043, odds ratio (OR) 9.474, 95 % confidence interval (CI) 1.069-83.957)]. Absence of hepatitis B e antigen (HBeAg) at the end of treatment was significantly associated with ALT rebound (P = 0.003, OR 13.500, 95 % CI 2.473-73.705). In HBeAg-positive patients, the HBV DNA + RNA titer after 3 months of treatment was marginally associated with ALT rebound (P = 0.050, OR 8.032, 95 % CI 0.997-64.683).Monitoring of serum HBV DNA + RNA levels may be a useful method for predicting re-activation of chronic hepatitis B after discontinuation of NA therapy.

Introduction: Sepsis is a serious medical condition that requires rapidly administered, appropriate antibiotic treatment. Conventional methods take three or more days for final pathogen identification and antimicrobial susceptibility testing. We organized a prospective observational multicenter study in three study sites to evaluate the diagnostic accuracy and potential clinical utility of the SeptiFast system, a multiplex pathogen detection system used in the clinical setting to support early diagnosis of bloodstream infections. Methods: A total of 212 patients, suspected of having systemic inflammatory response syndrome (SIRS) caused by bacterial or fungal infection, were enrolled in the study. From these patients, 407 blood samples were taken and blood culture analysis was performed to identify pathogens. Whole blood was also collected for DNA Detection Kit analysis immediately after its collection for blood culture. The results of the DNA Detection Kit, blood culture and other culture tests were compared. The chosen antimicrobial treatment in patients whose samples tested positive in the DNA Detection Kit and/or blood culture analysis was examined to evaluate the effect of concomitant antibiotic exposure on the results of these analyses. Results: SeptiFast analysis gave a positive result for 55 samples, while 43 samples were positive in blood culture analysis. The DNA Detection Kit identified a pathogen in 11.3% (45/400) of the samples, compared to 8.0% (32/400) by blood culture analysis. Twenty-three pathogens were detected by SeptiFast only; conversely, this system missed five episodes of clinically significant bacteremia (Methicillin-resistant Staphylococcus aureus (MRSA), 2; Pseudomonas aeruginosa ,1 ;Klebsiella spp ,1 ;Enterococcus faecium, 1). The number of samples that tested positive was significantly increased by combining the result of the blood culture analysis with those of the DNA Detection Kit analysis (P = 0.01). Among antibiotic pre-treated patients (prevalence, 72%), SeptiFast analysis detected more bacteria/fungi, and was less influenced by antibiotic exposure, compared with blood culture analysis (P = 0.02). Conclusions: This rapid multiplex pathogen detection system complemented traditional culture-based methods and offered some added diagnostic value for the timely detection of causative pathogens, particularly in antibiotic pre-treated patients. Adequately designed intervention studies are needed to prove its clinical effectiveness in improving appropriate antibiotic selection and patient outcomes.