Comparison of hepatitis B virus subgenotypes in patients with acute and chronic hepatitis B and absence of lamivudine-resistant strains in acute hepatitis B in Japan

Hepatitis B virus (HBV) has been classified into eight genotypes and can be further divided into several subgenotypes that have different geographic distributions. Because of increased human migration, the prevalence of rare subgenotypes is increasing in Japanese patients with acute hepatitis B. Lamivudine-resistant strains of HBV have begun to emerge in association with chronic hepatitis B. The aim of this study was to investigate the distribution of HBV subgenotypes and lamivudine-resistant strains in patients in Japan with acute hepatitis B. One hundred twenty-three patients with acute hepatitis B and 123 with chronic hepatitis B were studied. HBV subgenotypes and lamivudine-resistance mutations were determined by direct sequencing of the preS and polymerase region, respectively. HBV subgenotypes Aa (n=3), Ae (n=23), Ba (n=7), Bj (n=3), Cs (n=7), Ce (n=76), D (n=2), and H (n=2) were detected in patients with acute hepatitis. In patients with chronic hepatitis, HBV subgenotypes Ae (n=4), Ba (n=1), Bj (n=18), and Ce (n=100) were found. Non-common Japanese subgenotypes, that is, non-Bj and non-Ce, were detected more frequently in patients with acute hepatitis (35.8%) than in patients with chronic hepatitis (4.1%) (Odds ratio, 0.076; 95%CI, 0.029-0.200; P<0.0001). Lamivudine-resistance mutations were detected in chronic hepatitis patients with breakthrough hepatitis but not in other patients. In conclusion, the prevalence of uncommon Japanese HBV subgenotypes is expected to increase, although lamivudine-resistant strains have not yet been found in patients with acute hepatitis B.     

Carcinomatous Lymphatic Invasion in Early Gastric Cancer Invading Into the Submucosa

Background: Lymphatic invasion is a risk factor for lymph node metastases in patients with gastric cancer. No studies have been reported, however, on the correlation between lymphatic invasion and lymph node metastasis in early gastric cancer invading into the submucosa.Methods: We performed a retrospective analysis of lymphatic invasion in 170 patients with early gastric cancer invading into the submucosa.Results: Lymphatic invasion was found in 76 patients. Lymphatic invasion correlated significantly with the presence of lymph node metastasis and vascular invasion (P < .05) and with the degree of cancerous submucosal involvement (P < .05). The presence of lymph node metastasis also correlated with the grade of submucosal invasion and lymphatic invasion. The 5-year survival of patients with lymphatic invasion was poorer than that of patients without lymphatic invasion (P < .05). Node-negative patients had similar survival, regardless of the presence of lymphatic invasion. All patients with severe lymphatic invasion had sm3 invasion and lymph node metastases.Conclusion: Although lymphatic invasion is the first stage of lymph node metastasis, lymphatic invasion in itself does not have clinical importance except for severe invasion in early gastric cancer. It is possible to predict lymph node metastases from the combined evaluation of degree of lymphatic invasion and submucosal involvement of the tumor in patients with early gastric cancer invading into the submucosa.     

Infiltration of antitumor immunocytes into the sentinel node in gastric cancer

The sentinel node (SN) is regarded as the first drainage lymph node, and tumor cells are considered likely to directly affect the SN. However, few reports have identified differences between SNs and non-SNs in cancer patients. Subjects in this study included 27 patients with gastric cancer who underwent curative operation and intraoperative detection of SNs by radioisotope methods. The mean number of SNs was 3.2 (range 1 to 5). Degree of infiltration of natural killer cells, dendritic cells, MIB-1 labeling index, and CD3-ξ expression of lymphocytes in SNs and non-SNs were examined by means of immunohistochemical methods. Degree of infiltration was compared according to depth of invasion and between SNs and non-SNs. Patients with early-stage cancer displayed a greater degree of infiltration of MIB-1 labeling index and CD3-ξ expression than patients with pT2 or pT3 lesions (P<0.05). The MIB-1 labeling index in SNs was significantly lower than that in non-SNs (P<0.05). However, no significant difference was observed in infiltration of natural killer cells, dendritic cells, or CD3-ξ. Morphologic changes of dendritic cells in SNs were not definite. Our results suggest that SNs in gastric cancer might not be suppressed, unlike in breast cancer and melanoma. SN paralysis may depend on tumor- and organ-specific characteristics or exogenous stimulation from the gastric mucosa. Studies in progress will help to identify immunologic paralysis of the SN in various types of cancer. Attention must therefore be paid to organ specificity.     

Effects of right atrial pacing preference in prevention of paroxysmal atrial fibrillation: Atrial Pacing Preference study (APP study).

BACKGROUND: Several preliminary studies have indicated that atrial pacing can prevent atrial tachyarrhythmias. The suggested mechanisms by which pacing may be effective include suppression of premature atrial beats. METHODS AND RESULTS: The Atrial Pacing Preference (APP; Guidant, St Paul, MN, USA) algorithm allows the pacemaker to maintain a pacing rate slightly higher than the sinus rate. The preventive effects of APP on paroxysmal atrial fibrillation (AF) were studied in 51 patients (70+/-11 years). Nine patients did not complete the protocol. The pacemaker was programmed in random order to APP off and APP on at 3 different settings (ie, 8, 16 and 32 cycles) for 4 weeks each, using a cross-over design. Percentage atrial pacing was lower in APP off than at the other settings. Premature beat counts were greater in APP off than at the other settings. There was a significant difference in mode switch episode counts between APP off and the most effective setting (3,818+/-15,356 vs 596+/-1,719; p<0.01). CONCLUSIONS: The APP algorithm is a promising method for preventing atrial tachyarrhythmia in patients with an implanted pacemaker and AF. Optimizing the setting of the APP algorithm is an important issue in the prevention of AF.     

Comparison of direct sequencing and Invader assay for Y93H mutation and response to interferon‐free therapy in hepatitis C virus genotype 1b

Background and Aim

Virologic failure of interferon‐free therapy has been associated with Y93H mutation in the non‐structure 5A region in hepatitis C virus (HCV) genotype 1b, and screening is recommended. A simple assay based on Q‐Invader technology was developed for Y93H mutant screening to reduce cost and effort. The present study sought to compare two methods of detection of Y93H mutation and to evaluate the effect of Y93H mutation on response to interferon‐free therapy.

Methods

Y93H mutation was examined in 258 patients with HCV genotype 1b using both direct sequencing analysis and the polymerase chain reaction (PCR)‐Invader assay. Daclatasvir and asunaprevir or ledipasvir and sofosbuvir therapy was administered to 205 patients whose sustained virological responses (SVR) were checked.

Results

Hepatitis C virus was detected in 232 of 258 patients by direct sequencing and in 236 of 258 patients by the PCR‐Invader assay. Forty of 231 cases were defined as Y93 mutation by direct sequencing, and 46 of 236 cases were defined as Y93 mutation by the PCR‐Invader assay. SVR of patients who were Y93H by direct sequencing, Y93H by the PCR‐Invader assay, and Y93H by both methods was 62.5%, 82.4%, and 50%, respectively.

Conclusions

The sensitivity of the PCR‐Invader assay was similar to that of direct sequencing analysis; however, the PCR‐Invader assay had a better ability to detect minor strains. Combination of the two assays would improve prediction of the response to daclatasvir and asunaprevir, but Y93H mutation had little effect on SVR in ledipasvir and sofosbuvir therapy.     

Association of the Low-density Lipoprotein Cholesterol/High-density Lipoprotein Cholesterol Ratio with Glecaprevir-pibrentasvir Treatment

Objective The change in serum lipid levels by direct-acting antiviral (DAA) treatment for chronic hepatitis C varies depending on the type of DAA. How the lipid level changes induced by glecaprevir-pibrentasvir (G/P) treatment contribute to the clinical outcome remains unclear. We conducted a prospective observational study to evaluate the effectiveness of G/P treatment and the lipid level changes. Methods The primary endpoint was a sustained virologic response at 12 weeks (SVR12). The total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglyceride (TG) levels and LDL-C/HDL-C (L/H) ratio were measured every two weeks. Patients This study included 101 patients. Seventeen cases of liver cirrhosis and nine cases of DAA retreatment were registered. The G/P treatment period was 8 weeks in 74 cases and 12 weeks in 27 cases. Results SVR12 was evaluated in 96 patients. The rate of achievement of SVR12 in the evaluable cases was 100%. We found significantly elevated TC and LDL-C levels over the observation period compared to baseline. The serum levels of HDL-C did not change during treatment but were significantly increased after treatment compared to baseline. The L/H ratio was significantly increased two weeks after the start of treatment but returned to the baseline after treatment. Conclusion The primary endpoint of the SVR12 achievement rate was 100%. G/P treatment changed the serum lipid levels. Specifically, the TC and LDL-C levels increased during and after treatment, and the HDL-C levels increased after treatment. G/P treatment may be associated with a reduced thrombotic risk. Therefore, validation in large trials is recommended.     

Endoscopic ultrasound elastography for small solid pancreatic lesions with or without main pancreatic duct dilatation

Background/Objectives: Endoscopic ultrasound elastography (EUS-EG) is useful for diagnosis of small solid pancreatic lesions (SPLs), particularly in excluding pancreatic cancer (PC), but its dependence on main pancreatic duct dilatation (MPDD) has not been examined. We aimed to investigate EUS-EG for diagnosis of small SPLs with and without MPDD.MethodsPatients with pathologically diagnosed SPLs of ≤20 mm were included and retrospectively analyzed. Using the blue:green ratio, an EUS-EG image was classified as blue-dominant, equivalent, or green-dominant. Using multiple EUS-EG images per patient, a lesion with a greater number of blue-dominant than green-dominant images was classified as stiff, and the others as soft. EUS-EG images in random order were judged by three raters. Considering stiff SPLs as PC, diagnostic performance of EUS-EG was examined for SPLs with and without MPDD.ResultsOf 126 cases analyzed, 65 (52%) were diagnosed as PC, and 63 (50%) had MPDD. A total of 1077 EUS-EG images were examined (kappa coefficient = 0.783). Lesions were classified as stiff in 91 cases and soft in 35 (kappa coefficient = 0.932). The ratio of stiff to soft lesions was significantly higher in PC than in non-PC (62:3 vs. 29:32, P < 0.001). The sensitivity, specificity, and negative predictive value of a stiff lesion with vs. without MPDD for diagnosis of PC were 94%, 23%, and 50% vs. 100%, 60%, and 100%, respectively.ConclusionsUsing the EUS-EG stiffness classification for small SPLs, PC can be excluded with high confidence and concordance for a soft lesion without MPDD.