Entecavir treatment for chronic hepatitis B: adaptation is not needed for the majority of naïve patients with a partial virological response

Entecavir (ETV) is a potent inhibitor of viral replication in nucleos(t)ide analogue (NA)-naïve chronic hepatitis B (CHB) patients. The aim of this study was to investigate the long term efficacy and safety of ETV in NA-naïve CHB patients, particularly in those with detectable hepatitis B virus (HBV) DNA after 48 weeks, in whom treatment adaptation is suggested by current guidelines. In a multicenter cohort study, we investigated 333 CHB patients treated with entecavir monotherapy. The NA-naïve population consisted of 243 patients, whereas 90 were NA-experienced. Virological response (VR) (HBV DNA<80 IU/mL) was achieved in 48%, 76%, and 90% of hepatitis B e antigen (HBeAg)-positive and in 89%, 98%, and 99% of HBeAg-negative NA-naïve patients at weeks 48, 96, and 144, respectively. Thirty-six of 175 (21%) NA-naïve patients with at least 48 weeks of follow-up had a detectable load at week 48 (partial virological response [PVR]). Twenty-nine (81%) patients with PVR reached VR during prolonged ETV monotherapy, and none of them developed ETV-resistance. Among 22 patients with HBV DNA<1,000 IU/mL at week 48, VR was achieved in 21 (95%) patients, compared with eight of 14 (57%) patients with HBV DNA≥1,000 IU/mL. Continuous HBV DNA decline was observed in most patients without VR during follow-up, and in three patients adherence was suboptimal according to the treating physician. ETV was safe and did not affect renal function or cause lactic acidosis.

CONCLUSION

ETV monotherapy can be continued in NA-naïve patients with detectable HBV DNA at week 48, particularly in those with a low viral load because long-term ETV leads to a virological response in the vast majority of patients.

Humoral and Cellular Immune Response After Third and Fourth SARS-CoV-2 mRNA Vaccination in Liver Transplant Recipients

BACKGROUND & AIMS

Liver transplant recipients (LTRs) show a decreased immune response after 2 severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) vaccinations compared with healthy controls (HCs). Here, we investigated the immunogenicity of additional vaccinations.

METHODS

In this prospective study, humoral (anti-SARS-CoV-2 receptor-binding domain [anti-S RBD]) and cellular (interferon-gamma release assay) immune responses were determined after mRNA-based SARS-CoV-2 vaccination in 106 LTRs after a third vaccination and in 36 LTRs after a fourth vaccination. Patients with anti-S RBD antibody levels &gt;0.8 arbitrary unit (AU)/mL after vaccination were defined as responders.

RESULTS

After 3 vaccinations, 92% (97/106) of LTRs compared with 100% (28/28) of HCs were responders. However, the antibody titer of LTRs was lower compared with HCs (1891.0 vs 21,857.0 AU/mL; P &lt; .001). Between a second and third vaccination (n = 75), the median antibody level increased 67-fold in LTRs. In patients seronegative after 2 vaccinations, a third dose induced seroconversion in 76% (19/25), whereas all HCs were already seropositive after 2 vaccinations. A spike-specific T-cell response was detected in 72% (28/39) after a third vaccination compared with 32% (11/34) after a second vaccination. Independent risk factors for a low antibody response (anti-S RBD &lt;100 AU/mL) were first vaccination within the first year after liver transplant (odds ratio [OR], 8.00; P = .023), estimated glomular filtration rate &lt;45 mL/min (OR, 4.72; P = .006), and low lymphocyte counts (OR, 5.02; P = .008). A fourth vaccination induced a 9-fold increase in the median antibody level and seroconversion in 60% (3/5) of previous non-responders.

CONCLUSIONS

A third and fourth SARS-CoV-2 vaccination effectively increases the humoral and cellular immune response of LTRs, but to a lesser extent than in HCs. A fourth vaccination should be generally considered in LTRs.

Detection of a Broad Range of Low-Level Major Histocompatibility Complex Class II-Restricted, Hepatitis Delta Virus (HDV)-Specific T-Cell Responses Regardless of Clinical Status

Background

This study aimed to comprehensively define the breadth and specificity of the hepatitis delta virus (HDV)-specific T-cell response in patients at different stages of chronic coinfection with hepatitis B virus (HBV).

Methods

Following in vitro stimulation with an overlapping set of 21 HDV-specific 20mer peptides and exogenous interleukin 2, HDV-specific CD4+ and CD8+ T-cell responses of 32 HDV-infected patients were analyzed by enzyme-linked immunospot analysis and intracellular cytokine staining for interferon γ production at the single-peptide level. Additionally, HLA-binding studies were performed both in silico and in vitro.

Results

We were able to detect ≥1 T-cell response in >50% our patients. Interestingly, there was no significant difference between the breadth of the response in patients positive and those negative for HDV by PCR. HDV-specific T-cell responses focused on 3 distinct HDV-specific epitopes that were each detected in 12%-21% of patients-2 HLA class II-restricted epitopes (amino acids 11-30 and 41-60) and 1 major histocompatibility complex class I-restricted epitope (amino acids 191-210). In in vitro HLA-binding assays, the 2 CD4+ T-cell specificities (amino acids 11-30 and 41-60) showed promiscuous binding to multiple HLA-DR molecules.

Conclusions

This comprehensive characterization of HDV T-cell epitopes provides important information that will facilitate further studies of HDV immunopathogenesis.

Colitis Promotes a Pathological Condition of the Liver in the Absence of Foxp3+ Regulatory T Cells

Inflammatory bowel disease is associated with extraintestinal diseases such as primary sclerosing cholangitis in the liver. Interestingly, it is known that an imbalance between Foxp3⁺ regulatory T cells (Treg) and Th17 cells is involved in inflammatory bowel disease and also in primary sclerosing cholangitis. To explain these associations, one hypothesis is that intestinal inflammation and barrier defects promote liver disease because of the influx of bacteria and inflammatory cells to the liver. However, whether and how this is linked to the Treg and Th17 cell imbalance is unclear. To address this, we used dextran sodium sulfate (DSS) and T cell transfer colitis mouse models. We analyzed the pathological conditions of the intestine and liver on histological, cellular, and molecular levels. We observed bacterial translocation and an influx of inflammatory cells, in particular Th17 cells, to the liver during colitis. In the DSS colitis model, in which Treg were concomitantly increased in the liver, we did not observe an overt pathological condition of the liver. In contrast, the T cell-mediated colitis model, in which Treg are not abundant, was associated with marked liver inflammation and a pathological condition. Of note, upon depletion of Treg in DEREG mice, DSS colitis promotes accumulation of Th17 cells and a pathological condition of the liver. Finally, we studied immune cell migration using KAEDE mice and found that some of these cells had migrated directly from the inflamed intestine into the liver. Overall, these data indicate that colitis can promote a pathological condition of the liver and highlight an important role of Treg in controlling colitis-associated liver inflammation.

Comparison of one commercial and two in-house TaqMan multiplex real-time PCR assays for detection of enteropathogenic, enterotoxigenic and enteroaggregative Escherichia coli

OBJECTIVE

Enteropathogenic, enterotoxigenic and enteroaggregative Escherichia coli (EPEC, ETEC, EAEC) are among the most frequent causes of diarrhoea during travel or on military deployments. Cost-efficient and reliable real-time multiplex PCR (mPCR) assays are desirable for surveillance or point prevalence studies in remote and resource-limited tropical settings. We compared one commercial PCR kit and two in-house assays without using a gold standard to estimate sensitivity and specificity of each assay.

METHODS

Residual materials from nucleic acid extractions of stool samples from two groups with presumably different prevalences and increased likelihood of being infected or colonised by diarrhoeagenic E. coli were included in the assessment. One group comprised samples from returnees from tropical deployments, the second group was of migrants and study participants from high-endemicity settings. Each sample was assessed with all of the PCR assays. Cycle threshold (Ct) values were descriptively compared.

RESULTS

The calculated sensitivities for the commercial test vs. the in-house tests were for EPEC 0.84 vs. 0.89 and 0.96, for ETEC 0.83 vs. 0.76 and 0.61, and for EAEC 0.69 vs. 0.54 and 0.69. False positive results were rare - specificity was 0.94 and 0.97 for two EPEC tests and 1.0 for all other tests. Most positive samples had late Ct values corresponding to low quantities of pathogens. Discordant test results were associated with late Ct values.

CONCLUSIONS

As commercial and in-house assays showed comparable results, in-house tests can be assumed to be safe while affording considerable savings, making them a valuable alternative for surveillance testing in resource-limited tropical areas.

Microbial findings, sensitivity and outcome in patients with postoperative peritonitis a retrospective cohort study

BACKGROUND

Acute postoperative peritonitis resulting from previous abdominal surgery is still a severe and potentially fatal disease, which is associated with high morbidity and mortality. The aim of the present study was to evaluate patients' outcome after postoperative peritonitis and identify the most effective empiric antibiotic regimes.

METHODS

422 patients with acute postoperative peritonitis as a result to earlier abdominal operation (e.g. anastomotic leakage) were analyzed retrospectively focusing on the origin of the peritonitis, microbial flora and resistance patterns. Furthermore, mortality was estimated according to sensitivity results of the tested antibiotics.

RESULTS

In 50% of the patients, anastomotic leakage was located in the colon. The predominantly cultured microorganisms were Escherichia coli and Enterobacteriaceae. The combination of meropenem and vancomycin was effective in 96% of these microbes. The frequently used combinations of piperacillin/sulbactam and cefotaxime/metronidazole were effective in only 67% and 43%, respectively.

CONCLUSIONS

We were able to show that the currently used antibiotic regimes with piperacillin/sulbactam and cefotaxime/metronidazole are ineffective in a relevant number of patients with anastomotic leakage. Only meropenem or meropenem/vancomycin cover most of the microbes predominant in postoperative peritonitis.

Epidemiology of co-infections in pregnant women living with human immunodeficiency virus 1 in rural Gabon: a cross-sectional study

BACKGROUND

There is no recent epidemiological data on HIV infection in Gabon, particularly in pregnant women. To close this gap, an HIV-prevalence survey was conducted among Gabonese pregnant women, followed by a cross-sectional case-control study in which the prevalence of various co-infections was compared between HIV-positive and HIV-negative pregnant women.

METHODS

Between 2018 and 2019, data for the HIV-prevalence survey were collected retrospectively in 21 Gabonese antenatal care centres (ANCs). Subsequently, for the prospective co-infection study, all HIV-positive pregnant women were recruited who frequented the ANC in Lambaréné and a comparator sub-sample of HIV-negative pregnant women was recruited; these activities were performed from February 2019 to February 2020. The mean number of co-infections was ascertained and compared between HIV-positive and HIV-negative women. Additionally, the odds for being co-infected with at least one co-infection was evaluated and compared between HIV-positive and HIV-negative women.

RESULTS

HIV-positivity was 3.9% (646/16,417) among pregnant women. 183 pregnant women were recruited in the co-infection study. 63% of HIV-positive and 75% of HIV-negative pregnant women had at least one co-infection. There was a trend indicating that HIV-negative women were more often co-infected with sexually transmitted infections (STIs) than HIV-positive women [mean (standard deviation, SD): 2.59 (1.04) vs 2.16 (1.35), respectively; P = 0.056]; this was not the case for vector-borne infections [mean (SD): 0.47 (0.72) vs 0.43 (0.63), respectively; P = 0.59].

CONCLUSIONS

Counterintuitively, the crude odds for concomitant STIs was lower in HIV-positive than in HIV-negative women. The change of magnitude from the crude to adjusted OR is indicative for a differential sexual risk factor profile among HIV-positive and HIV-negative women in this population. This might potentially be explained by the availability of sexual health care counselling for HIV-positive women within the framework of the national HIV control programme, while no such similar overall service exists for HIV-negative women. This highlights the importance of easy access to sexual healthcare education programmes for all pregnant women irrespective of HIV status.

Impact of SARS-CoV-2 vaccination in patients with vascular liver diseases: Observations from a VALDIG multicenter study

Background & Aims

Patients with vascular liver diseases (VLD) are at higher risk of both severe courses of COVID-19 disease and thromboembolic events. The impact of SARS-CoV-2 vaccination in patients with VLD has not been described and represents the aim of our study.

Methods

International, multicenter, prospective observational study in patients with VLD analyzing the incidence of COVID-19 infection after vaccination, severity of side effects, occurrence of thromboembolic events and hepatic decompensation. In a subgroup of patients, the humoral and cellular responses to vaccination were also analyzed.

Results

A total of 898 patients from 14 European centers - part of the VALDIG network - were included, 872 (97.1%) patients received two vaccine doses (fully vaccinated), and 674 (75.1%) three doses. Of the total cohort, 151/898 had a COVID-19 infection prior to vaccination, of whom 9/151 (5.9%) were re-infected. Of the 747/898 patients who were not previously infected, 11.2% (84/747) were diagnosed with a COVID-19 infection during the study period. Two infected patients required intensive care unit admission and infection was fatal in two fully vaccinated patients. Adverse effects were reported in around 40% of patients, with local side effects being the most frequent. During the study period, 31 (3.5%) patients had thromboembolic events and 21 (2.3%) hepatic decompensations. No cases of vaccine-induced thrombocytopenia were reported. Vaccine immunogenicity was assessed in 36 patients; seroconversion reached 100% and IFNy T-cell responses significantly increased post two mRNA-1273 vaccine doses.

Conclusion

Patients with VLD seem to have a preserved immune response to SARS-CoV-2 vaccination, which appears to be safe and effective in preventing severe COVID-19 infection. Our study cannot definitively establish a direct link between vaccination and thrombotic events, though the contribution of vaccination as a cofactor in VLD remains to be elucidated.

Impact and implications

Patients with vascular liver disease (VLD) are at increased risk of both SARS-CoV-2 infection and severe COVID-19 disease. The potential risks associated with vaccination against this infection need thorough investigation. Our research enhances the understanding of the effects of COVID-19 vaccination in patients with VLD, highlighting its good tolerability. Moreover, patients with VLD appear to have a preserved immune response to SARS-CoV-2 vaccination, providing protection against severe COVID-19 infection. Our study cannot definitively establish a direct link between vaccination and thrombotic events, and no cases of vaccine-induced thrombocytopenia were reported.