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1.
Liver Int ; 42(12): 2674-2682, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36152268

RESUMEN

BACKGROUND AND AIMS: Low anti-HBc serum levels at the time of therapy cessation were linked to a higher relapse risk in predominantly HBeAg-positive cohorts. We investigated the association of anti-HBc levels with relapse in HBeAg-negative patients. METHODS: Serum levels of anti-HBc, HBsAg and HBcrAg were determined in 136 HBeAg-negative patients, participating in a vaccination trial (ABX-203, NCT02249988), before treatment cessation or vaccination. Importantly, vaccination showed no impact on relapse. The correlation between the biomarkers and their predictive value for relapse (HBV DNA >2000 IU/ml ± ALT >2xULN) was investigated. RESULTS: After therapy cessation 50% (N = 68) of patients relapsed. Median anti-HBc prior to treatment stop was significantly higher among relapsers compared to off-treatment responders (520 IU/ml vs. 330 IU/mL, p = .0098). The optimal anti-HBc cut-off to predict relapse was 325 IU/ml according to the Youden-Index. About 35% of patients with anti-HBc level < 325 IU/ml versus 60% of those with values ≥325 IU/mL relapsed (p = .0103; sensitivity 50%, specificity 75%). Combining the optimal cut-offs of HBsAg (>3008 IU/mL) or HBcrAg (≥1790 U/ml) with anti-HBc increased the proportion of patients with relapse to 80% (p < .0001) and 74% (p = .0006), respectively. CONCLUSION: In contrast to predominantly HBeAg-positive cohorts, in our cohort of HBeAg-negative patients lower anti-HBc levels are associated with a significantly lower relapse risk after nucleos(t)ide analogue cessation. The vast majority of included patients were either genotype B or C and the applicability to other genotypes has to be further evaluated. However, anti-HBc level as an indicator of the host response might be prospectively further explored for prediction models.


Asunto(s)
Antígenos de Superficie de la Hepatitis B , Antígenos e de la Hepatitis B , Humanos , Antivirales/uso terapéutico , Resultado del Tratamiento , Anticuerpos contra la Hepatitis B , Recurrencia , Virus de la Hepatitis B/genética , ADN Viral
2.
Z Gastroenterol ; 60(6): 959-962, 2022 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-34666403

RESUMEN

Antiviral therapy of chronic hepatitis C virus (HCV) achieves sustained virological response (SVR) in the majority of patients. Even after initial virological failure, re-treatment with the combination of sofosbuvir+velpatasvir+voxilaprevir (SOF/VEL/VOX) has been established as an effective second line regimen. However, some patients fail to achieve SVR after a second antiviral course with SOF/VEL/VOX. These patients are considered difficult-to-cure. Currently, the optimal regimen for antiviral re-re-treamtent is a matter of debate and European and American guidelines suggest the combination of SOF+glecaprevir/pibrentasvir (G/P) + Ribavirin as a salvage regimen. However, there is only little evidence to support this. In this study, data of two patients with genotype 3 chronic HCV infection, liver cirrhosis and virological failure after re-treatment with SOF/VEL/VOX that successfully achieved SVR with the combination of SOF+G/P ± RBV. Importantly, one patient had Child B cirrhosis to the time of treatment initiation. No adverse events were reported. Thus, our data support the use of SOF + G/P + RBV as a salvage regimen after re-treatment failure with SOF/VEL/VOX.


Asunto(s)
Hepatitis C Crónica , Sofosbuvir , Ácidos Aminoisobutíricos , Antivirales/uso terapéutico , Bencimidazoles , Carbamatos , Niño , Ciclopropanos , Quimioterapia Combinada , Genotipo , Hepacivirus/genética , Hepatitis C Crónica/diagnóstico , Hepatitis C Crónica/tratamiento farmacológico , Compuestos Heterocíclicos de 4 o más Anillos , Humanos , Lactamas Macrocíclicas , Leucina/análogos & derivados , Prolina/análogos & derivados , Pirrolidinas , Quinoxalinas , Ribavirina/uso terapéutico , Sofosbuvir/uso terapéutico , Sulfonamidas , Insuficiencia del Tratamiento , Resultado del Tratamiento
3.
J Viral Hepat ; 28(8): 1206-1218, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34003549

RESUMEN

Improvement of health-related quality of life (HRQoL) is frequently reported as a benefit when treating hepatitis C virus infection (HCV) with direct acting antivirals (DAA). As most of the available data were obtained from clinical trials, limited generalizability to the real-world population might exist. This study aimed to investigate the impact of DAA therapy on changes in HRQoL in a real-world setting. HRQoL of 1180 participants of the German Hepatitis C-Registry was assessed by Short-Form 36 (SF-36) questionnaires. Scores at post-treatment weeks 12-24 (FU12/24) were compared to baseline (BL). Changes of ≥2.5 in mental and physical component summary scores (MCS and PCS) were defined as a minimal clinical important difference (MCID). Potential predictors of HRQoL changes were analysed. Overall, a statistically significant increase in HRQoL after DAA therapy was observed, that was robust among various subgroups. However, roughly half of all patients failed to achieve a clinically important improvement in MCS and PCS. Low MCS (p < .001, OR = 0.925) and PCS (p < .001, OR = 0.899) BL levels were identified as predictors for achieving a clinically important improvement. In contrast, presence of fatigue (p = .023, OR = 1.518), increased GPT levels (p = .005, OR = 0.626) and RBV containing therapy regimens (p = .001, OR = 1.692) were associated with a clinically important decline in HRQoL after DAA therapy. In conclusion, DAA treatment is associated with an overall increase of HRQoL in HCV-infected patients. Nevertheless, roughly half of the patients fail to achieve a clinically important improvement. Especially patients with a low HRQoL seem to benefit most from the modern therapeutic options.


Asunto(s)
Hepatitis C Crónica , Hepatitis C , Antivirales/uso terapéutico , Hepacivirus , Hepatitis C/tratamiento farmacológico , Hepatitis C Crónica/tratamiento farmacológico , Humanos , Calidad de Vida , Sistema de Registros , Resultado del Tratamiento
6.
Viruses ; 16(2)2024 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-38400031

RESUMEN

BACKGROUND: The hepatitis B core-related antigen (HBcrAg) correlates with HBV DNA in patients with chronic HBV infection without antiviral treatment. Its utility in monitoring patients during and after the cessation of nucleos(t)ide analog (NA) treatment is unknown. METHODS: The levels of HBcrAg were longitudinally determined in two cohorts of chronic HBV-infected patients with (A) newly started NA treatment or (B) after NA cessation during a median follow up (FU) of 60 months or 48 weeks, respectively. The correlation of HBcrAg and HBV DNA and the predictive value for HBeAg seroconversion and HBsAg loss were evaluated. RESULTS: Fifty-six patients with newly-started NA treatment and 22 patients with NA cessation were identified. HBcrAg and HBV DNA strongly correlated before NA treatment (r = 0.77, p < 0.0001) and at virological relapse (0.66, p = 0.0063). At the individual level, the discrepant kinetics of HBcrAg and HBV DNA became evident. During NA treatment, 33% (6/18) and 9% (5/56) of patients showed HBeAg seroconversion or HBsAg loss/HBsAg < 100 IU/mL, respectively. Low levels of HBcrAg were associated with these endpoints. CONCLUSION: HBcrAg levels before antiviral treatment help to identify patients with chances of HBsAg loss or HBeAg seroconversion. However, its utility in replacing quantitative HBV DNA to evaluate treatment efficacy or virological relapse off-treatment is limited.


Asunto(s)
Hepatitis B Crónica , Humanos , Antígenos del Núcleo de la Hepatitis B , Antígenos de Superficie de la Hepatitis B , Antígenos e de la Hepatitis B , ADN Viral , Antivirales/uso terapéutico , Recurrencia , Virus de la Hepatitis B/genética
7.
Open Forum Infect Dis ; 8(8): ofab325, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34377724

RESUMEN

To achieve global hepatitis C virus (HCV) eradication, barriers prohibiting treatment access need to be overcome. We established a strategy to initiate antiviral therapy in patients with severe, refractory heroin addiction. All patients achieved sustained virological response. Outreach programs of hepatologists might be a reasonable way to overcome barriers to HCV treatment.

8.
Elife ; 92020 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-33084573

RESUMEN

Crimean-Congo hemorrhagic fever (CCHF) is the most widely distributed tick-borne viral infection in the world. Strikingly, reported mortality rates for CCHF are extremely variable, ranging from 5% to 80% (Whitehouse, 2004). CCHF virus (CCHFV, Nairoviridae) exhibits extensive genomic sequence diversity across strains (Deyde et al., 2006; Sherifi et al., 2014). It is currently unknown if genomic diversity is a factor contributing to variation in its pathogenicity. We obtained complete genome sequences of CCHFV directly from the tick reservoir. These new strains belong to a solitary lineage named Europe 2 that is circumstantially reputed to be less pathogenic than the epidemic strains from Europe 1 lineage. We identified a single tick-specific amino acid variant in the viral glycoprotein region that dramatically reduces its fusion activity in human cells, providing evidence that a glycoprotein precursor variant, present in ticks, has severely impaired function in human cells.


Crimean-Congo hemorrhagic fever (CCHF) is caused by infection with a virus spread by ticks in Europe, Africa and Asia. It can cause severe disease in humans, including high fevers and bleeding. How deadly CCHF is varies with between 5% to 80% of those infected dying. Scientists suspect genetic differences in various strains of the virus may account for the differences in death rates, but they do not know the exact mutations that make the CCHF virus more or less deadly. To learn more, scientists have sorted strains of CCHF virus into different groups based on how similar they are genetically. One group called Europe 2 infects many people in the Balkans, but it rarely causes illness. In fact, only two mild cases of illness have been associated with Europe 2 strains, while other CCHF virus strains circulating in this region have caused thousands of more severe illnesses. Now, Hua et al. identified a mutation in one Europe 2 strain of the CCHF virus that may explain why this subgroup of viruses rarely causes severe human disease. The researchers collected a strain of CCHF virus from infected ticks found in Bulgaria and sequenced its genome. They named the virus strain Malko Tarnovo. Through a series of experiments, Hua et al. showed that the Malko Tarnovo strain very efficiently infects tick cells but not human cells. A single amino acid change in the genetic sequence of the virus appears to make the virus less able to infect human cells. The mutation prevents a protein on the surface of the virus from fusing with human cells, an essential step in infection. This may explain why this strain and others in the Europe 2 group do not cause severe human disease. Hua et al. also demonstrate the importance of studying viruses in the animals that spread them. By studying the CCHF virus in ticks, scientists may be able to learn more about how viruses evolve to infect new species, which may help scientists prevent future pandemics.


Asunto(s)
Virus de la Fiebre Hemorrágica de Crimea-Congo/patogenicidad , Sustitución de Aminoácidos/genética , Animales , Vectores Arácnidos/virología , Europa (Continente) , Variación Genética/genética , Genoma Viral/genética , Virus de la Fiebre Hemorrágica de Crimea-Congo/genética , Fiebre Hemorrágica de Crimea/virología , Humanos , Filogenia , Garrapatas/virología
9.
Ticks Tick Borne Dis ; 10(3): 697-703, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30871930

RESUMEN

The discovery of the first tick-borne phleboviruses associated with severe disease in humans stimulated studies searching for further previously unknown tick-associated viruses. Novel phleboviruses have subsequently been identified in ticks from the USA, Japan and China and recently also from Europe. Here, we investigated the genetic diversity of tick-borne phleboviruses originating from Strandja Nature Park, Bulgaria, a unique primary forest with evergreen plants that was not affected by the last ice ages in the Pleistocene and Holocene. We found a high genetic diversity of 12 phleboviral sequences in 1542 ticks. The sequences formed five distinct groups and clustered with other tick-borne phleboviruses recently identified in Europe. Although isolation experiments of the detected viruses in cell culture failed, viral RNA copy numbers were stable up to 42 days post infection (dpi) in the supernatant of tick cells whereas they disappeared 14 dpi in that of VeroE6/7 cells. In summary, nearly all tick-associated phleboviruses known to occur in Europe have been detected in one geographic region. Our data show that primary ecosystems in temperate regions are also rich in viral diversity and that this is not only true for tropical regions.


Asunto(s)
Variación Genética , Ixodes/virología , Phlebovirus/clasificación , Animales , Bulgaria , Chlorocebus aethiops , Europa (Continente)/epidemiología , Femenino , Masculino , Parques Recreativos , Phlebovirus/aislamiento & purificación , Filogenia , ARN Viral/genética , Análisis de Secuencia de ADN , Células Vero
10.
Parasit Vectors ; 11(1): 165, 2018 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-29554928

RESUMEN

BACKGROUND: Ticks are important carriers of many different zoonotic pathogens. To date, there are many studies about ticks and tick-borne pathogens (TBP), but only a few were carried out in Bulgaria. The present study intends to detect the prevalence of tick-borne bacteria and parasites occurring at the Black Sea in Bulgaria to evaluate the zoonotic potential of the tick-borne pathogens transmitted by ticks in this area. METHODS: In total, cDNA from 1541 ticks (Dermacentor spp., Haemaphysalis spp., Hyalomma spp., Ixodes spp. and Rhipicephalus spp.) collected in Bulgaria by flagging method or from hosts was tested in pools of ten individuals each for Anaplasma phagocytophilum, Babesia spp., Borrelia burgdorferi (s.l.), Rickettsia spp. and "Candidatus Neoehrlichia mikurensis" via conventional and quantitative real-time PCR. Subsequently, samples from positive pools were tested individually and a randomized selection of positive PCR samples was purified, sequenced, and analyzed. RESULTS: Altogether, 23.2% of ticks were infected with at least one of the tested pathogens. The highest infection levels were noted in nymphs (32.3%) and females (27.5%). Very high prevalence was detected for Rickettsia spp. (48.3%), followed by A. phagocytophilum (6.2%), Borrelia burgdorferi (s.l.) (1.7%), Babesia spp. (0.4%) and "Ca. Neoehrlichia mikurensis" (0.1%). Co-infections were found in 2.5% of the tested ticks (mainly Ixodes spp.). Sequencing revealed the presence of Rickettsia monacensis, R. helvetica, and R. aeschlimannii, Babesia microti and B. caballi, and Theileria buffeli and Borrelia afzelli. CONCLUSION: This study shows very high prevalence of zoonotic Rickettsia spp. in ticks from Bulgaria and moderate to low prevalence for all other pathogens tested. One should take into account that tick bites from this area could lead to Rickettsia infection in humans and mammals.


Asunto(s)
Bacterias/genética , Variación Genética , Parásitos/genética , Zoonosis/epidemiología , Animales , Babesia/genética , Babesia/aislamiento & purificación , Bacterias/clasificación , Bacterias/aislamiento & purificación , Infecciones Bacterianas/epidemiología , Borrelia/genética , Borrelia/aislamiento & purificación , Infecciones por Borrelia/epidemiología , Bulgaria/epidemiología , Coinfección/epidemiología , Coinfección/microbiología , Coinfección/parasitología , ADN Bacteriano/genética , Femenino , Humanos , Ixodes/microbiología , Ixodes/parasitología , Ninfa/microbiología , Ninfa/parasitología , Parásitos/clasificación , Parásitos/aislamiento & purificación , Enfermedades Parasitarias/epidemiología , Prevalencia , Rickettsia/genética , Rickettsia/aislamiento & purificación , Infecciones por Rickettsia/epidemiología , Infestaciones por Garrapatas/microbiología , Infestaciones por Garrapatas/parasitología , Zoonosis/microbiología , Zoonosis/parasitología
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