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1.
J Viral Hepat ; 24(12): 1089-1097, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28581644

RESUMEN

Community-based real-world outcomes on effectiveness of antiviral therapies for chronic hepatitis B virus (CHB) in Asians are limited. Whether hepatitis B surface antigen (HBsAg) loss correlates with undetectable virus and alanine aminotransferase (ALT) normalization on treatment or what predicts risk of seroreversion or detectable virus after stopping therapy is unclear. We aim to evaluate rates and predictors of HBsAg loss, seroconversion, ALT normalization and undetectable HBV DNA, including HBsAg seroreversion or re-emergence of HBV DNA among Asian CHB patients. We retrospectively evaluated 1072 CHB adults on antiviral therapy at two community gastroenterology clinics from 1997 to 2015. Rates of HBsAg loss, ALT normalization, achieving undetectable HBV DNA and developing surface antibody (anti-HBs) were stratified by HBeAg status. Following HBsAg loss, HBsAg seroreversion or re-emergence of detectable HBV DNA was analysed. With median treatment of 76.7 months, the overall rate of HBsAg loss was 4.58%, with similar HBsAg loss rates between HBeAg-positive and HBeAg-negative patients (4.44% vs 4.71%, P=.85) in a predominantly Asian population (98.1%). Among HBsAg loss patients, 33.3% developed anti-HBs, 95.8% achieved undetectable virus and 66.0% normalized ALT. No significant baseline or on-treatment predictors of HBsAg loss were observed. While six patients who achieved HBsAg loss had seroreversion with re-emergence of HBsAg positivity, viral load remained undetectable, demonstrating the sustainability of viral suppression. Among a large community-based real-world cohort of Asian CHB patients treated with antiviral therapy, rate of HBsAg loss was 4.58%. Despite only 33.3% of HBsAg loss patients achieving anti-HBs, nearly all patients achieved sustained undetectable virus.


Asunto(s)
Antivirales/uso terapéutico , Antígenos de Superficie de la Hepatitis B/sangre , Hepatitis B Crónica/tratamiento farmacológico , Hepatitis B Crónica/virología , Respuesta Virológica Sostenida , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Alanina Transaminasa/sangre , Asia , ADN Viral/sangre , Femenino , Anticuerpos contra la Hepatitis B , Hepatitis B Crónica/patología , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Seroconversión , Resultado del Tratamiento , Carga Viral , Adulto Joven
2.
J Viral Hepat ; 24(1): 17-21, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27677786

RESUMEN

Sofosbuvir/ledipasvir (SOF/LDV) is the first all-oral ribavirin-free treatment approved for chronic hepatitis C virus (HCV) genotype 6, offering a safe and highly efficacious treatment option. Large studies evaluating real-world outcomes of this regimen are lacking. We aim to evaluate real-world treatment outcomes for HCV genotype 6. A retrospective cohort study evaluated 65 adults (age ≥18) with chronic HCV genotype 6 treated with SOF/LDV without ribavirin at a community gastroenterology clinic in the United States from November 2014 to May 2016. Rates of undetectable virus at week 4 on treatment, at end of treatment (EOT) and SVR12 were stratified by the presence of cirrhosis and prior treatment (treatment naïve vs treatment experienced). Among 65 patients with chronic HCV genotype 6 treated with SOF/LDV (52.3% male, mean age 66.3 years [SD 9.7], 41.5% cirrhosis and 15.4% treatment experienced), 97.3% had undetectable virus at week 4 on treatment, 96.9% had undetectable virus at EOT and 95.3% achieved SVR12. SVR12 was 100% in females vs 91.2% in males, P=.096, and 92.3% in patients with cirrhosis vs 97.4% in those without cirrhosis, P=.347. Resistance testing of treatment failures was attempted but unsuccessful due to lack of conforming primers to define the possible resistance mutations. Among the largest U.S. community-based real-world cohort of Asian chronic HCV genotype 6 patients treated with all-oral SOF/LDV without ribavirin, SVR12 was similar to SVR12 reported in clinical trials, confirming the safety and effectiveness of this regimen and validating current HCV genotype 6 treatment guideline recommendations.


Asunto(s)
Antivirales/uso terapéutico , Bencimidazoles/uso terapéutico , Fluorenos/uso terapéutico , Genotipo , Hepacivirus/clasificación , Hepacivirus/genética , Hepatitis C Crónica/tratamiento farmacológico , Sofosbuvir/uso terapéutico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Asiático , Femenino , Hepacivirus/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Respuesta Virológica Sostenida , Resultado del Tratamiento , Estados Unidos , Adulto Joven
3.
JIMD Rep ; 25: 87-94, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26219882

RESUMEN

Liver transplantation has been reported in patients with methylmalonic acidemia (MMA), but long-term outcome is controversial. Many patients with other approved indications for liver transplantation die before donor grafts are available. A 28-year-old man with MMA underwent cadaveric liver transplantation. His liver was used as a domino graft for a 61-year-old man with primary sclerosing cholangitis, who had low priority on the transplant waiting list. Surgical outcome was successful, and after transplantation both patients have excellent graft function. The patient with MMA showed substantial decrease in methylmalonate in urine (from 5,277 ± 1,968 preoperatively to 1,068 ± 384 mmol/mol creatinine) and plasma (from 445.9 ± 257.0 to 333.3 ± 117.7 µmol/l) over >1-year follow-up, while dietary protein intake increased from 0.6 to 1.36 ± 0.33 g/kg/day. The domino recipient maintained near-normal levels of plasma amino acids but did develop elevated methylmalonate in blood and urine while receiving an unrestricted diet (peak plasma methylmalonate 119 µmol/l and urine methylmalonate 84-209 mmol/mol creatinine, with 1.0-1.9 g/kg/day protein). Neither patient demonstrated any apparent symptoms of MMA or metabolic decompensation during the postoperative period or following discharge. CONCLUSION: Liver transplantation substantially corrects methylmalonate metabolism in MMA and greatly attenuates the disease. In this single patient experience, a liver from a patient with MMA functioned well as domino graft although it did result in subclinical methylmalonic acidemia and aciduria in the recipient. Patients with MMA can be considered as domino liver donors for patients who might otherwise spend long times waiting for liver transplantation.

4.
J Viral Hepat ; 21(12): 905-8, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24779356

RESUMEN

Early identification of chronic hepatitis B is important for optimal disease management and prevention of transmission. Cost and lack of access to commercial hepatitis B surface antigen (HBsAg) immunoassays can compromise the effectiveness of HBV screening in resource-limited settings and among marginalized populations. High-quality point-of-care (POC) testing may improve HBV diagnosis in these situations. Currently available POC HBsAg assays are often limited in sensitivity. We evaluated the NanoSign(®) HBs POC chromatographic immunoassay for its ability to detect HBsAg of different genotypes and with substitutions in the 'a' determinant. Thirty-seven serum samples from patients with HBV infection, covering HBV genotypes A-G, were assessed for HBsAg titre with the Roche Elecsys HBsAg II quantification assay and with the POC assay. The POC assay reliably detected HBsAg at a concentration of at least 50 IU/mL for all genotypes, and at lower concentrations for some genotypes. Eight samples with substitutions in the HBV 'a' determinant were reliably detected after a 1/100 dilution. The POC strips were used to screen serum samples from 297 individuals at risk for HBV in local clinical settings (health fairs and outreach events) in parallel with commercial laboratory HBsAg testing (Quest Diagnostics EIA). POC testing was 73.7% sensitive and 97.8% specific for detection of HBsAg. Although the POC test demonstrated high sensitivity over a range of genotypes, false negatives were frequent in a clinical setting. Nevertheless, the POC assay offers advantages for testing in both developed and resource-limited countries due to its low cost (0.50$) and immediately available results.


Asunto(s)
Cromatografía de Afinidad/métodos , Pruebas Diagnósticas de Rutina/métodos , Antígenos de Superficie de la Hepatitis B/sangre , Hepatitis B Crónica/diagnóstico , Sistemas de Atención de Punto , Reacciones Falso Negativas , Genotipo , Virus de la Hepatitis B/genética , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad
5.
J Viral Hepat ; 18(4): e40-51, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21143342

RESUMEN

Although chronic hepatitis B (CHB) affects approximately 2 million United States residents, there is no systematic screening of at-risk individuals, and most remain unaware of their hepatitis B virus (HBV) infection. Unmonitored and untreated, CHB results in a 25-30% risk of death from liver cancer and/or cirrhosis, inflicting an increasing healthcare burden in high-prevalence regions. Despite high prevalence in immigrant Asians and Pacific Islanders, among whom CHB is a leading cause of death, community and healthcare provider awareness remains low. Because safe and effective vaccines and effective antiviral treatments exist, there is an urgent need for integrated programmes that identify, follow and treat people with existing CHB, while vaccinating the susceptible. We describe an extant San Francisco programme that integrates culturally targeted, population-based, HBV screening, vaccination or reassurance, management and research. After screening over 3000 at-risk individuals, we here review our operational and practical experience and describe a simple, rationally designed model that could be successfully used to greatly improve the current approach to hepatitis B while ultimately reducing the related healthcare costs, especially in the high-risk populations, which are currently underserved.


Asunto(s)
Hepatitis B/epidemiología , Hepatitis B/prevención & control , Hepatitis B/diagnóstico , Hepatitis B/tratamiento farmacológico , Vacunas contra Hepatitis B/administración & dosificación , Humanos , Tamizaje Masivo/métodos , San Francisco/epidemiología , Vacunación/métodos
6.
J Viral Hepat ; 18(6): 377-83, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21143343

RESUMEN

Chronic infection with the hepatitis B virus (HBV) is a major risk factor for development of end-stage liver disease, including cirrhosis, liver failure and primary liver cancer. There are now seven antiviral agents approved by the United States Food and Drug Administration (FDA) for the management of chronic HBV infection. Despite the fact that there are between 1.4 and 2 million chronic HBV infections in the United States, fewer than 50,000 people per year receive prescriptions for HBV antiviral medications. This report discusses possible explanations for the disparity between the number of people who are chronically infected and the number of people who receive treatment. Explanations for this incongruence include the potentially large number of infected persons who are unscreened and thus remain undiagnosed, and lack of access, including insurance, education and referral to appropriate medical care, particularly for disproportionately infected populations.


Asunto(s)
Antivirales/uso terapéutico , Disparidades en Atención de Salud , Hepatitis B Crónica/tratamiento farmacológico , Enfermedad Hepática en Estado Terminal/diagnóstico , Enfermedad Hepática en Estado Terminal/tratamiento farmacológico , Virus de la Hepatitis B , Hepatitis B Crónica/diagnóstico , Humanos , Estados Unidos , Vacunación
7.
J Viral Hepat ; 17(1): 16-22, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19622117

RESUMEN

This retrospective analysis was conducted to describe the characteristics of nucleoside-naïve hepatitis B e antigen (HBeAg)-positive patients with chronic hepatitis B, who achieved hepatitis B surface antigen (HBsAg) loss during entecavir or lamivudine therapy. HBeAg-positive adults with chronic hepatitis B, elevated serum alanine aminotransferase, and compensated liver disease were randomized to double-blind treatment for up to 96 weeks with entecavir 0.5 mg/day or lamivudine 100 mg/day. HBsAg and hepatitis B virus (HBV) DNA were measured at regular intervals during and off-treatment follow-up. Through a maximum duration of 96 weeks on-treatment and 24 weeks off-treatment, HBsAg loss was confirmed in 18/354 (5.1%) patients treated with entecavir and 10/355 (2.8%) patients treated with lamivudine. Among the 28 patients with confirmed HBsAg loss, 27 (96%) achieved HBV DNA <300 copies/mL, and 27 (96%) achieved confirmed HBeAg loss. All entecavir recipients with HBsAg loss had HBV DNA <300 copies/mL. Caucasian patients, and those infected with HBV genotype A or D, were significantly more likely to lose HBsAg. This retrospective analysis of data from a randomized, global phase three trial shows that confirmed loss of HBsAg occurred in 5% of nucleoside-naïve HBeAg-positive patients treated with entecavir, and that HBsAg loss is associated with sustained off-treatment suppression of HBV DNA.


Asunto(s)
Antivirales/uso terapéutico , Guanina/análogos & derivados , Antígenos de Superficie de la Hepatitis B/sangre , Antígenos e de la Hepatitis B/sangre , Hepatitis B Crónica/tratamiento farmacológico , Lamivudine/uso terapéutico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Alanina Transaminasa/sangre , ADN Viral/sangre , Método Doble Ciego , Femenino , Guanina/uso terapéutico , Virus de la Hepatitis B/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento , Carga Viral , Adulto Joven
8.
J Viral Hepat ; 16(11): 784-9, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19457141

RESUMEN

Entecavir is a potent inhibitor of hepatitis B virus (HBV) polymerase. The efficacy and safety of entecavir in nucleoside-naïve patients with hepatitis B virus e antigen (HBeAg)-positive chronic hepatitis B was established in a large, international, double-dummy study (ETV-022) where patients were randomized to entecavir 0.5 mg/day (n = 354) or lamivudine 100 mg/day (n = 355) once daily. ETV-022 had a 52-week blinded treatment phase, followed by an extended blinded treatment phase for up to 44 additional weeks (96 weeks total). Treatment was discontinued for patients achieving a protocol-defined response as determined by patient management criteria that intended to test the possibility of finite therapy, which has not previously been studied for entecavir or other anti-HBV agents in a large trial. Early results from this study have been previously presented/published separately. This paper compiles the results of up to 2 years of treatment for protocol-defined responders, virologic responders and nonresponders. For responders who discontinued therapy (per protocol), 24-week off-treatment evaluation is presented to provide a more 'complete picture' of what clinicians can expect when treating nucleoside-naïve HBeAg-positive patients with chronic hepatitis B. For patients who discontinued therapy because of nonresponse (nonresponders) and subsequently entered the rollover study ETV-901, follow-up results, including resistance profile, are provided.


Asunto(s)
Antivirales , Guanina/análogos & derivados , Antígenos e de la Hepatitis B/sangre , Hepatitis B Crónica/tratamiento farmacológico , Lamivudine , Antivirales/administración & dosificación , Antivirales/efectos adversos , Antivirales/farmacología , Antivirales/uso terapéutico , ADN Viral/sangre , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Farmacorresistencia Viral , Guanina/administración & dosificación , Guanina/efectos adversos , Guanina/farmacología , Guanina/uso terapéutico , Virus de la Hepatitis B/efectos de los fármacos , Hepatitis B Crónica/virología , Humanos , Lamivudine/administración & dosificación , Lamivudine/efectos adversos , Lamivudine/farmacología , Lamivudine/uso terapéutico , Pruebas de Sensibilidad Microbiana , Factores de Tiempo , Resultado del Tratamiento
9.
Aliment Pharmacol Ther ; 27(12): 1240-52, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18373637

RESUMEN

BACKGROUND: Several anti-viral treatments are now available for HBeAg-negative chronic hepatitis B (CHB), but the clinical and economic outcomes of potential treatment strategies and durations are unclear. AIM: To examine the clinical and economic outcomes of potential treatment strategies and durations for HBeAg-negative CHB. METHODS: We conducted a cost-utility analysis from a payer perspective over a lifetime time horizon. Disease progression probabilities, costs and quality of life data were derived from the literature. We evaluated 5-year, 10-year, lifetime and 5 on-1 off treatment durations. For each of these treatment durations, we evaluated initial therapy with entecavir, lamivudine or adefovir, with addition of adefovir or entecavir for patients who developed virological breakthrough because of resistance (12 strategies total). RESULTS: Increasing treatment duration improved quality-adjusted life-years (QALYs) and was generally cost-effective for all three drugs. However, a 5 on-1 off strategy was the most cost-effective: lifetime vs. 5 on-1 off entecavir had an ICER of $148,200/QALY. In probabilistic sensitivity analyses, entecavir 5 on-1 off was the preferred strategy over the range of commonly reimbursed cost-effectiveness thresholds. Lifetime treatment was preferred to a 5 on-1 off strategy, if treatment durability was < 10%. CONCLUSION: The results of our analysis suggest that in HBeAg-negative CHB infection, a 5 on-1 off treatment strategy with entecavir improves health outcomes in a cost-effective manner compared to alternative strategies.


Asunto(s)
Adenina/análogos & derivados , Antivirales/uso terapéutico , Guanina/análogos & derivados , Hepatitis B Crónica/tratamiento farmacológico , Organofosfonatos/uso terapéutico , Adenina/economía , Adenina/uso terapéutico , Antivirales/economía , Análisis Costo-Beneficio , Métodos Epidemiológicos , Guanina/economía , Guanina/uso terapéutico , Antígenos e de la Hepatitis B/metabolismo , Hepatitis B Crónica/economía , Humanos , Lamivudine/economía , Lamivudine/uso terapéutico , Organofosfonatos/economía
10.
J Viral Hepat ; 13(12): 787-98, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17109678

RESUMEN

Hepatitis B virus (HBV) remains a serious health threat in many parts of the world. Although its prevalence is lower in the Americas than in Asia, Africa and the Middle East, it is responsible for significant morbidity and mortality in North, Central and South America. There is a nonuniform pattern of distribution throughout this region, with HBV prevalence related to geographical, social and cultural factors that predispose certain individuals to infection. This report details the incidence, modes of viral transmission of hepatitis B in the Americas and clinical course of disease in different regions of the Americas. Additionally, the implications for management focusing on issues predominant in high-risk populations are presented.


Asunto(s)
Hepatitis B Crónica/epidemiología , Américas/epidemiología , Ensayos Clínicos como Asunto , Hepatitis B Crónica/terapia , Hepatitis B Crónica/transmisión , Humanos
11.
J Viral Hepat ; 12(5): 465-72, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16108760

RESUMEN

SUMMARY: Both absolute viral load and log decline in viral load from baseline were found clinically useful in predicting sustained virological response and lack of sustained virological response (non-sustained virological response, NSVR) to treatment. We assessed the clinical utility of hepatitis C virus (HCV) RNA quantitation and changes in viral load using the VERSANT HCV RNA 3.0 Assay (bDNA) in 351 HCV-infected individuals treated with interferon plus ribavirin. We show that viral load decision thresholds provided negative predictive values (NPVs) of >95% at week 4 using a 100 000 IU/mL cut-off and at weeks 8 and 12 using 10 000 IU/mL cut-offs. A 2-log decline from baseline provided NPVs >95% at weeks 8 and 12. Combinations of absolute viral loads and changes in viral load from baseline did not enhance the performance of the decision rules for predicting NSVR. The positive predictive values (PPVs) at weeks 8 and 12 were 59.1 and 67.3%. This study highlights the critical importance of viral quantitation in gauging therapeutic response in patients with chronic HCV infection on antiviral therapy. Early changes in viral load, measured as absolute viral loads or change in viral load from baseline, are highly predictive of NSVR at 8 and 12 weeks. PPVs are modest but these data may provide encouragement to patients who are in the early phases of treatment when side effects are frequent. Additionally, we demonstrated the need for cautious interpretation of stopping rules when the values are at or near the decision thresholds.


Asunto(s)
Antivirales/uso terapéutico , Hepacivirus/fisiología , Hepatitis C Crónica/tratamiento farmacológico , ARN Viral/genética , Carga Viral , Adulto , Anciano , Antivirales/administración & dosificación , Estudios de Cohortes , Femenino , Hepacivirus/clasificación , Hepacivirus/efectos de los fármacos , Hepatitis C Crónica/sangre , Hepatitis C Crónica/virología , Humanos , Interferón-alfa/uso terapéutico , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , ARN Viral/sangre , Estudios Retrospectivos , Ribavirina/administración & dosificación , Ribavirina/uso terapéutico , Resultado del Tratamiento , Viremia/tratamiento farmacológico , Viremia/virología
12.
J Viral Hepat ; 11(6): 488-501, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15500549

RESUMEN

There are eight genotypes and nine subtypes of HBV. Small differences in geographical origin are associated with sequence changes in the surface gene. Here, we compared core gene sequences from different genotypes and geographical regions. Specific combinations of 24 amino acid substitutions at nine residues allowed allocation of a sequence to a subtype. Six of these nine residues were located in different T cell epitopes depending on HBV geographical area and/or genotype. Thirty-seven nucleotide changes were associated uniquely with specific genotypes and subtypes. Unique amino acid and nucleotide variants were found in a majority of sequences from specific countries as well as within subtype ayw2 and adr. Specific nucleotide motifs were defined for Korean, Indian, Chinese, Italian and Pacific region isolates. Finally, we observed amino acid motifs that were common to either South-east Asian or Western populations, irrespective of subtype. We believe that HBV strains spread within constrained ethnic groups, result in selection pressures that define sequence variability within each subtype. It suggests that particular T cell epitopes are specific for geographical regions, and thus ethnic groups; this may affect the design of immunomodulatory therapies.


Asunto(s)
Variación Genética , Antígenos del Núcleo de la Hepatitis B/química , Antígenos del Núcleo de la Hepatitis B/genética , Virus de la Hepatitis B/clasificación , Hepatitis B/epidemiología , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Asia Sudoriental , Secuencia de Bases , Europa (Continente) , Genotipo , Hepatitis B/virología , Antígenos de Superficie de la Hepatitis B/sangre , Virus de la Hepatitis B/genética , Humanos , India , Datos de Secuencia Molecular , Filogenia , Análisis de Secuencia de ADN
13.
J Viral Hepat ; 11(3): 243-50, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15117326

RESUMEN

Interferon alpha and ribavirin (RBV) combination therapy is associated with decreases in haemoglobin (Hb) concentrations and anaemia. The aim of this analysis was to better characterize the magnitude and frequency of Hb changes and risk factors. This retrospective analysis evaluated treatment-related changes in Hb in 677 patients who participated in either of two interferon alpha-2b plus RBV studies for chronic hepatitis C virus (HCV) infection. Study 1 included 192 interferon alpha-naïve patients randomized to receive RBV 1000-1200 mg/day plus interferon alpha-2b 3 million IU daily or three times weekly for 48 weeks. Study 2 included 485 interferon alpha-experienced patients randomized to receive RBV 1000-1200 mg daily plus interferon alpha-2b 3 million IU daily or three times weekly for 4 weeks, followed by three times weekly dosing for 44 weeks. More than 50% of all patients experienced a decrease in Hb > or =30 g/L. Women were 4.4 times as likely as men to experience a Hb level of <100 g/L; however, men were at a 40% higher risk to experience a Hb decline of >30 g/L from baseline. Daily use of interferon alpha-2b did not impact the magnitude of Hb decrease. In this pooled analysis, RBV dose reduction resulted in increases in Hb concentration of approximately 10 g/L. Lower baseline creatinine clearance, higher baseline Hb levels and increased age were independently associated with increased risk of Hb decreases of >27.7%. Lower baseline weight was not associated with increased risk of Hb decrease. Substantial Hb decreases occur frequently with interferon alpha/RBV combination therapy. Sex, the magnitude of the Hb decline and renal function are potentially important factors to consider in patients receiving RBV. Further research is needed to determine the impact on virological response and to develop strategies to manage the medical consequences.


Asunto(s)
Hemoglobinas/metabolismo , Hepatitis C Crónica/sangre , Hepatitis C Crónica/tratamiento farmacológico , Interferón-alfa/administración & dosificación , Ribavirina/administración & dosificación , Anemia Hemolítica/etiología , Antivirales/administración & dosificación , Antivirales/efectos adversos , Combinación de Medicamentos , Quimioterapia Combinada , Femenino , Humanos , Interferón-alfa/efectos adversos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Ribavirina/efectos adversos , Factores de Riesgo , Factores Sexuales
14.
Antimicrob Agents Chemother ; 46(6): 1734-40, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12019083

RESUMEN

A multicenter, open-label study was performed to evaluate the safety, anti-hepatitis B virus (anti-HBV) activity, and pharmacokinetics of emtricitabine therapy administered once daily for 8 weeks to patients infected with HBV. Clinical and virologic evaluations were completed at the baseline; at 7, 14, 28, 42, and 56 days during treatment; and at 24, 48, and 28 days posttreatment. Forty-nine patients were enrolled in five dose cohorts (doses of 25, 50, 100, 200, and 300 mg, all of which were administered once daily [q.d.]). Peak plasma emtricitabine concentrations occurred within 1.5 h following dosing. Plasma emtricitabine concentrations (maximum concentrations of drug in plasma and areas under the concentration-time curves) increased nearly dose proportionally over the 25- to 300-mg dose range, with relatively small intersubject variabilities. The plasma half-life of emtricitabine ranged from 6 to 9 h. HBV DNA levels were measured by the Digene HBV Hybrid Capture II assay. Viral suppression (reduction in log(10) serum HBV DNA levels) occurred in all dose cohorts. All doses demonstrated potent and rapid antiviral activities, with a trend toward a greater suppression with daily doses of 100 mg or greater. At 2 months, the median change in the serum HBV DNA level from the baseline level ranged from -1.7 log(10) for the 25-mg dose administered q.d. to -3.3 log(10) for the 300 mg dose administered q.d. Emtricitabine was well tolerated over the 2-month dosing period. These results support further clinical development of emtricitabine for the treatment of chronic hepatitis B infection.


Asunto(s)
Antivirales/uso terapéutico , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapéutico , Hepatitis B/tratamiento farmacológico , Adolescente , Adulto , Algoritmos , Antivirales/efectos adversos , Antivirales/farmacocinética , Área Bajo la Curva , Estudios de Cohortes , Desoxicitidina/efectos adversos , Desoxicitidina/farmacocinética , Relación Dosis-Respuesta a Droga , Emtricitabina , Femenino , Hepatitis B/virología , Antígenos de Superficie de la Hepatitis B/sangre , Humanos , Pruebas de Función Hepática , Masculino , Persona de Mediana Edad , Modelos Biológicos , Carga Viral
15.
J Virol Methods ; 98(2): 153-9, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11576642

RESUMEN

Hepatitis B virus (HBV) has been classified into six genotypes designated A-F by sequence divergence in the entire genome exceeding 8%. Very recently, the seventh genotype was reported and named genotype G. HBV genotype G is distinct from genomes of the other six genotypes in that it possesses an insertion of 36 nucleotides in the core gene, and has been found so far in France and the United States. A method for determining HBV genotype G was developed by polymerase chain reaction (PCR) with primers deduced from the 36-nucleotide (nt) insertion in five isolates of HBV genotype G the sequences of which have been deposited in DNA databases. The validity of this method, for specifically detecting HBV genotype G, was verified on a panel consisting of 142 HBV isolates of six major genotypes and four of genotype G. A total of 540 sera containing HBV in Japan covering symptom free carriers and patients with a spectrum of chronic liver disease were tested by this method, but not a single HBV genotype G sample was found. A possible method for serological determination of hepatitis B surface antigen of genotype G is suggested, without amplification or sequencing nucleotides, which would expand epidemiological and clinical researches on HBV genotype G.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Antígenos de Superficie de la Hepatitis B/inmunología , Virus de la Hepatitis B/genética , Precursores de Proteínas/inmunología , Secuencia de Aminoácidos , Secuencia de Bases , Secuencia Conservada , Cartilla de ADN , Ensayo de Inmunoadsorción Enzimática , Epítopos , Amplificación de Genes , Tamización de Portadores Genéticos/métodos , Genotipo , Antígenos de Superficie de la Hepatitis B/genética , Virus de la Hepatitis B/clasificación , Virus de la Hepatitis B/aislamiento & purificación , Humanos , Japón/epidemiología , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Precursores de Proteínas/genética , Sensibilidad y Especificidad , Análisis de Secuencia de ADN , Homología de Secuencia de Ácido Nucleico , Proteínas del Envoltorio Viral
16.
J Med Virol ; 65(1): 23-9, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11505439

RESUMEN

The genotype of hepatitis C virus (HCV) can profoundly affect the success of antiviral therapy for HCV infection. A possible contributing factor is a varied immune response elicited by infection with different HCV genotypes. In this study, full-length E2 proteins of HCV genotypes 1a, 1b, 2a, and 2b were used to determine the fraction of the humoral immune response to HCV E2 that is genotype specific. Greater than 90% of all infected individuals had serum antibodies to the four E2 proteins. Overall, individuals infected with genotype 1a or 1b were characterized by variable immune responses to HCV E2 with relatively high amounts of cross-reactivity with other E2 proteins. Individuals infected with genotype 2a or 2b exhibited a strong preferential reactivity to genotype 2a and 2b E2 proteins. Individuals with elevated titers to HCV E2 were more likely to be infected with genotype 2a and had a significantly lower median viral load. These findings indicate that the antibody response to HCV E2 is affected by the genotype of the virus and that induction of a strong humoral immune response to HCV E2 may contribute to a decreased viral load.


Asunto(s)
Hepacivirus/inmunología , Anticuerpos contra la Hepatitis C/inmunología , Hepatitis C/inmunología , Proteínas del Envoltorio Viral/inmunología , Adulto , Anciano , Reacciones Cruzadas , Femenino , Genotipo , Hepacivirus/clasificación , Hepacivirus/genética , Hepacivirus/fisiología , Hepatitis C/virología , Anticuerpos contra la Hepatitis C/sangre , Humanos , Masculino , Persona de Mediana Edad , Carga Viral
17.
Liver Transpl ; 7(7): 581-7, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11460224

RESUMEN

The selection of patients with cirrhosis and the diagnosis of alcohol dependence or abuse who have a long-term high probability of abstinence after orthotopic liver transplantation (OLT) may enhance patient survival and outcomes. The aim of this study is to identify factors that would predict which patients would consume alcohol after OLT. Sixty-one patients with a history of alcohol dependence or abuse underwent OLT from June 1989 to June 1994 and were followed up monthly for a median of 6.9 years after OLT (range, 2.5 to 9.3 years). Survival analysis techniques (Cox proportional hazard model) were used to identify patients at high risk for recidivism. Recidivism occurred in 12 of 61 patients (20%) after OLT during follow-up. Noncompliance, with a relative hazard of 20.9 (95% confidence interval [CI], 5.6 to 78.3; P <.001), and personality disorder, with a relative hazard of 6.0 (95% CI, 1.9 to 18.7; P =.002), independently predicted recidivism among patients who underwent OLT. These data indicate that specific behaviors and psychiatric diagnoses can be used to select patients at high risk for drinking alcohol before and after OLT.


Asunto(s)
Alcoholismo/complicaciones , Hepatopatías Alcohólicas/cirugía , Trasplante de Hígado , Cooperación del Paciente , Adulto , Anciano , Femenino , Estudios de Seguimiento , Humanos , Hepatopatías Alcohólicas/etiología , Masculino , Persona de Mediana Edad , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Recurrencia , Asunción de Riesgos
18.
Clin Liver Dis ; 5(2): 287-314, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11385965

RESUMEN

The diagnosis and management of autoimmune hepatitis continues to evolve as new diagnostic tests and new therapies are added to the armamentarium. Also encouraging are the advances in the understanding of the human immune system and its involvement in the origin and course of auto immune diseases in general and in the variants of autoimmune liver disease. Promising changes are expected in the next few years as new medications become available to the practicing hepatologist. New immune tests may allow therapies to be customized to patients, and antiviral therapies may also eventually be used in the management of this autoimmune liver diseases.


Asunto(s)
Enfermedades Autoinmunes , Hepatopatías , Antiinflamatorios/uso terapéutico , Enfermedades Autoinmunes/clasificación , Enfermedades Autoinmunes/diagnóstico , Enfermedades Autoinmunes/tratamiento farmacológico , Azatioprina/uso terapéutico , Colagogos y Coleréticos/uso terapéutico , Colangitis Esclerosante/diagnóstico , Colangitis Esclerosante/tratamiento farmacológico , Colangitis Esclerosante/inmunología , Hepatitis Autoinmune/diagnóstico , Hepatitis Autoinmune/tratamiento farmacológico , Humanos , Inmunosupresores/uso terapéutico , Cirrosis Hepática Biliar/diagnóstico , Cirrosis Hepática Biliar/tratamiento farmacológico , Cirrosis Hepática Biliar/inmunología , Hepatopatías/diagnóstico , Hepatopatías/tratamiento farmacológico , Hepatopatías/inmunología , Trasplante de Hígado , Prednisona/uso terapéutico , Pronóstico , Ácido Ursodesoxicólico/uso terapéutico
19.
N Engl J Med ; 344(21): 1580-7, 2001 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-11372009

RESUMEN

BACKGROUND: About 10 percent of patients who undergo liver transplantation have cryptogenic liver disease. In animal models, the absence of heteropolymeric keratins 8 and 18 or the presence of mutant keratins in hepatocytes causes or promotes liver disease. We have previously described a mutation in the keratin 18 gene in a patient with cryptogenic cirrhosis, but the importance of mutations in the keratin 8 and keratin 18 genes in such patients is unclear. METHODS: We tested for mutations in the keratin 8 and keratin 18 genes in purified genomic DNA isolated from 150 explanted livers and 89 peripheral-blood specimens from three groups of patients: 55 patients with cryptogenic liver disease; 98 patients with noncryptogenic liver disease, with causes that included alcohol use, autoimmunity, drug use, and viral infections; and 86 randomly selected inpatients and outpatients who provided blood to the hematology laboratory. RESULTS: Of the 55 patients with cryptogenic liver disease, 3 had glycine-to-cysteine mutations at position 61 (a highly conserved glycine) of keratin 8, and 2 had tyrosine-to-histidine mutations at position 53 of keratin 8. These mutations were not detected in the patients with other liver diseases or in the randomly selected patients. We verified the presence of the mutations in specimens of explanted livers by protein analysis and by the detection of unique restriction-enzyme cleavage sites. In transfected cells, the glycine-to-cysteine mutation limited keratin-filament reorganization when the cells were exposed to oxidative stress. In contrast, the tyrosine-to-histidine mutation destabilized keratin filaments when transfected cells were exposed to heat or okadaic acid stress. CONCLUSIONS: Mutations in the keratin 8 gene may predispose people to liver disease and may account for cryptogenic liver disease in some patients.


Asunto(s)
Queratinas/genética , Cirrosis Hepática/genética , Mutación Puntual , Secuencia de Aminoácidos , Secuencia de Bases , Línea Celular/química , Línea Celular/citología , Citoesqueleto/patología , Análisis Mutacional de ADN , Femenino , Técnica del Anticuerpo Fluorescente , Hepatitis/genética , Humanos , Immunoblotting , Queratina-8 , Queratinas/análisis , Queratinas/química , Hígado/química , Cirrosis Hepática/etnología , Cirrosis Hepática/cirugía , Trasplante de Hígado , Masculino , Distribución Aleatoria , Transfección
20.
Hepatology ; 33(2): 424-32, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11172345

RESUMEN

Seventy-seven liver transplant candidates were enrolled in a multicenter study in which patients were treated with lamivudine (100 mg daily) without the adjunctive use of hepatitis B immune globulin. Treatment was begun while patients awaited liver transplantation and continued after transplantation. All were hepatitis B surface antigen (HBsAg) positive, and 61% had detectable hepatitis B e antigen (HBeAg) and HBV DNA when treatment was begun. Forty-seven underwent liver transplantation and 30 did not. Median study participation was 38 months (range, 2.7-48.5) in the transplanted patients and 26 months (range, 0.1-37) in the nontransplanted group. Twenty-five of 42 (60%) transplanted patients with 12 or more weeks of posttransplantation follow-up were HBsAg negative at the last study visit. At treatment week 156, 13 of 22 (59%) remained HBsAg negative, and all 9 reinfected patients were HBV-DNA positive before treatment. In the nontransplanted patients, HBeAg was initially detectable in 20 of 27 (74%) but this decreased to 3 of 17 (18%) after 104 weeks of treatment, and significant improvement in biochemical parameters was observed. HBV-DNA polymerase mutants were detected in 15 (21%) and 6 (20%) of the transplanted and nontransplanted patients, respectively. When compared with historical cohorts, lamivudine-treated patients appeared to have improved survival, and transplanted patients had a decrease in the rate of recurrent HBV infection. Lamivudine therapy was partially effective in preventing recurrent HBV infection when given before and after transplantation. Thus, future trials using a combination of HBIg and lamivudine are needed to assess the optimal prophylactic therapy.


Asunto(s)
Hepatitis B Crónica/terapia , Lamivudine/uso terapéutico , Trasplante de Hígado , Cuidados Posoperatorios , Cuidados Preoperatorios , Inhibidores de la Transcriptasa Inversa/uso terapéutico , Adulto , Anciano , ADN Polimerasa Dirigida por ADN/genética , Femenino , Virus de la Hepatitis B/genética , Humanos , Lamivudine/efectos adversos , Masculino , Persona de Mediana Edad , Mutación , Inhibidores de la Transcriptasa Inversa/efectos adversos , Seguridad , Prevención Secundaria , Análisis de Supervivencia
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