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1.
Prev Med ; 137: 106132, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32442444

RESUMEN

Early treatment of HIV infection increases life expectancy and reduces infectivity; however, delayed HIV diagnosis remains common. Implementation and sustainability of hospital-based routine HIV testing in Vancouver, British Columbia, was evaluated to address a local HIV epidemic by facilitating earlier diagnosis and treatment. Public health issued a recommendation in 2011 to offer HIV testing to all patients presenting to three Vancouver hospitals as part of routine care, including all patients admitted to medical/surgical units with expansion to emergency departments (ED). We evaluated acceptability, feasibility, and effectiveness from 2011 to 2014 and continued monitoring through 2016 for sustainability. Between October 2011-December 2016, 114,803 HIV tests were administered at the three hospitals; an 11-fold increase following implementation of routine testing. The rate of testing was sustained and remained high through 2018. Of those tested, 151 patients were diagnosed with HIV for a testing yield of 0.13%. Review of 12,996 charts demonstrated 4935/5876 (96·9%) of admitted patients agreed to have an HIV test when offered. People diagnosed in hospital were significantly more likely to be diagnosed with acute stage (aOR 1·96, 95% CI 1·19, 3·23) infection, particularly those diagnosed in the ED. This study provides practice-based evidence of the feasibility, acceptability, and effectiveness of implementing a recommendation for routine HIV testing among inpatient and emergency department admissions, as well as the ability to normalize and sustain this change. Routine hospital-based HIV testing can increase diagnoses of acute HIV infection and facilitate earlier initiation of antiretroviral treatment.


Asunto(s)
Servicio de Urgencia en Hospital , Epidemias , Infecciones por VIH , Colombia Británica/epidemiología , Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología , Prueba de VIH , Hospitales , Humanos , Tamizaje Masivo
2.
J Clin Microbiol ; 54(1): 127-33, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26537448

RESUMEN

Sanger sequencing or DNA hybridization have been the primary modalities for hepatitis B (HBV) resistance testing and genotyping; however, there are limitations, such as low sensitivity and the inability to detect novel mutations. Next-generation sequencing (NGS) for HBV can overcome these limitations, but there is limited guidance for clinical microbiology laboratories to validate this novel technology. In this study, we describe an approach to implementing deep pyrosequencing for HBV resistance testing and genotyping in a clinical virology laboratory. A nested PCR targeting the pol region of HBV (codons 143 to 281) was developed, and the PCR product was sequenced by the 454 Junior (Roche). Interpretation was performed by ABL TherapyEdge based on European Association for the Study of the Liver (EASL) guidelines. Previously characterized HBV samples by INNO-LiPA (LiPA) were compared to NGS with discordant results arbitrated by Sanger sequencing. Genotyping of 105 distinct samples revealed a concordance of 95.2% (100/105), with Sanger sequencing confirming the NGS result. Resistance testing by NGS was concordant with LiPA in 85% (68/80) of previously characterized samples. Additional mutations were found in 8 samples, which related to the identification of low-level mutant subpopulations present at <10% (6/8). To balance the costs of testing for the validation study, reproducibility of the NGS was investigated through an analysis of sequence variants at loci not associated with resistance in a single patient sample. Our validation approach attempts to balance costs with efficient data acquisition.


Asunto(s)
Técnicas de Genotipaje/métodos , Virus de la Hepatitis B/efectos de los fármacos , Virus de la Hepatitis B/genética , Hepatitis B Crónica/virología , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Pruebas de Sensibilidad Microbiana/métodos , Costos y Análisis de Costo , ADN Viral/química , ADN Viral/genética , Virus de la Hepatitis B/aislamiento & purificación , Humanos , Mutación , Reacción en Cadena de la Polimerasa , Reproducibilidad de los Resultados
3.
Can Liver J ; 2(4): 190-198, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-35992763

RESUMEN

BACKGROUND: We examined changes in hepatitis B virus (HBV) viral loads (VLs) in pregnancy, their association with hepatitis B e antigen (HBeAg), and the associated infant outcomes. METHODS: We prospectively followed 132 mothers positive for hepatitis B surface antigen (HBsAg) and their 135 infants from 2011 to 2015 in Vancouver, British Columbia. Outcome measures included association between maternal HBeAg and high (>200,000 IU/mL) or low (≤200,000 IU/mL) HBV VL, changes in HBV VL through pregnancy, infant HBsAg status, and infant completion of the HBV vaccination series. RESULTS: f the 91 participants with an available HBV VL, 13 (14.3%) had an HBV VL of more than 200,000 IU/mL. Of 59 participants with paired HBeAg and HBV VL in pregnancy, 6 had an HBV VL of more than 200,000 IU/mL; of interest, 2 of the 6 (33.3%) were HBeAg-negative. Thirty-eight participants had HBV VL results at both mid-trimester and delivery. For these 38 participants, Wilcoxon signed-ranks test for paired data found that an HBV VL remained stable (p = .58). We observed no perinatal transmissions. However, 20.7% of infants did not have a documented complete HBV vaccination series, 20.0% did not have post-vaccination HBsAg testing completed, and 18% did not have anti-HBs titres measured by age 12 months. CONCLUSIONS: Our study demonstrates that HBeAg and HBV VL are not reliably predictive of each other. This supports the improved predictive value of VL measurement in pregnancy to risk stratify pregnant patients to offer antiviral treatment when indicated and further minimize the risk of perinatal transmission.

4.
Transplantation ; 81(1): 129-31, 2006 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-16421489

RESUMEN

With today's donor organ shortage, enhanced efforts must be made to utilize organs that previously would have been declined. We report a 26-year-old man with chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) coinfection who received a liver transplant from an HBsAg-positive donor. HBV viremia (6,281,185 copies/ml) was seen early posttransplant despite lamivudine prophylaxis, but became negative with addition of adefovir. Virologic analysis revealed predominantly donor HBV strain immediately posttransplant. At 5 months there was an elevation of liver enzymes accompanied by histologic evidence of hepatitis. At this time, HCV-RNA was positive but HBV DNA was undetectable. Treatment with pegylated interferon and ribavirin resulted in sustained clearance of HCV RNA. Two years posttransplant, the patient has normal liver biochemistry and HCV and HBV viral load are undetectable with persistence of HBsAg. Our experience suggests that with effective antiviral therapy, the use of HBsAg seropositive donors is feasible in selected circumstances.


Asunto(s)
Antígenos de Superficie de la Hepatitis B/análisis , Hepatitis B/inmunología , Trasplante de Hígado , Donantes de Tejidos , Adulto , Cadáver , Hepacivirus/aislamiento & purificación , Hepatitis B/tratamiento farmacológico , Hepatitis B/cirugía , Hepatitis B/virología , Antígenos de Superficie de la Hepatitis B/inmunología , Virus de la Hepatitis B/enzimología , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/inmunología , Virus de la Hepatitis B/aislamiento & purificación , Hepatitis C/complicaciones , Hepatitis C/cirugía , Hepatitis C/virología , Humanos , Masculino , Mutación/genética , Trasplante Homólogo
5.
Can J Gastroenterol Hepatol ; 28(10): 525-8, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25390612

RESUMEN

BACKGROUND: Perinatal transmission of hepatitis B virus (HBV) can occur despite postexposure prophylaxis (PEP). Recent literature suggests that antiviral treatment during pregnancy when maternal HBV DNA levels are elevated can further decrease vertical transmission. However, HBV DNA screening is not routinely performed antenatally. OBJECTIVE: To determine the rates of HBV prevalence and perinatal transmission in an antenatal cohort. METHODS: A retrospective review of public health records (December 2008 to December 2010) was performed for both mothers and newborns. RESULTS: A total of 725 mother-infant pairs were included. Of these, 574 of 715 (80%) women had antenatal hepatitis B e antigen (HBeAg) testing performed, and 127 of 574 (22%) were HBeAg positive (HBeAg+). Of babies born to hepatitis B surface antigen-positive (HBsAg+) mothers, only 573 of 725 (79%) received complete PEP. In addition, 172 of 725 (24%) infants did not receive post-PEP blood testing or were lost to follow-up. Of the 552 infants with results available, seven cases (1.3%) of mother-to-child HBV transmission were observed, six of which involved infants born to HBeAg+ women. CONCLUSIONS: Our findings suggest that routine HBeAg screening could identify a subset of mother-infant pairs among HBsAg+ pregnant women who are at higher risk for vertical HBV transmission. Determination of viral load in expectant HBeAg+ mothers may provide more precise insight into HBV transmission to their infants.


Asunto(s)
Hepatitis B/prevención & control , Hepatitis B/transmisión , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Adulto , Estudios de Cohortes , ADN Viral/sangre , Femenino , Antígenos de Superficie de la Hepatitis B/sangre , Vacunas contra Hepatitis B/administración & dosificación , Antígenos e de la Hepatitis B/sangre , Virus de la Hepatitis B/inmunología , Humanos , Lactante , Recién Nacido , Perdida de Seguimiento , Masculino , Profilaxis Posexposición , Embarazo , Complicaciones Infecciosas del Embarazo/inmunología , Estudios Retrospectivos , Carga Viral/genética
6.
Am J Hematol ; 81(12): 969-72, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16937392

RESUMEN

Hepatitis B reactivation is a well-known complication during or after chemotherapy in chronic hepatitis B (HBV) carriers. The current practice guidelines in Canada and the United States recommends patients receive antiviral prophylaxis prior to the onset of chemotherapy in chronic HBV carriers with lamivudine. We report a case of a 57-year-old man with follicular lymphoma on lamivudine prophylaxis and no clinical evidence of cirrhosis, and developed fatal HBV reactivation after the emergence of a YMDD mutant strain of HBV that confers lamivudine resistance. Fatal reactivation secondary to the development of lamivudine resistance has not, to date, been well- reported. Our experience indicates the need to carefully monitor patients for suspected drug- resistant HBV mutants with the addition of anti-viral agents effective against the YMDD mutational strain, when lamivudine resistance emerges.


Asunto(s)
Farmacorresistencia Viral , Hepatitis B Crónica/prevención & control , Lamivudine/administración & dosificación , Inhibidores de la Transcriptasa Inversa/administración & dosificación , Activación Viral/efectos de los fármacos , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Farmacorresistencia Viral/efectos de los fármacos , Farmacorresistencia Viral/genética , Resultado Fatal , Hepatitis B Crónica/complicaciones , Hepatitis B Crónica/genética , Humanos , Lamivudine/efectos adversos , Cirrosis Hepática/etiología , Cirrosis Hepática/genética , Linfoma Folicular/complicaciones , Linfoma Folicular/tratamiento farmacológico , Linfoma Folicular/virología , Masculino , Persona de Mediana Edad , Mutación , Inhibidores de la Transcriptasa Inversa/efectos adversos
7.
J Clin Microbiol ; 44(3): 1115-9, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16517908

RESUMEN

To assess the reproducibility of measurements of cervical and vaginal human immunodeficiency virus (HIV) viral load, 92 duplicate cervical and 88 duplicate vaginal samples were collected from 13 HIV-infected women using Sno Strip filter-paper wicks. RNA was eluted from the strips, extracted, and assayed using a modified protocol for the Roche Cobas Amplicor HIV-1 Monitor assay. Pearson's correlation coefficient (R), coefficient of determination (D), and Bland-Altman plots (BA) were used to compare paired log10-transformed viral loads. Analysis of duplicate same-site samples showed good reproducibility (cervix: R = 0.72, D = 52%, BA = 89% within range; vagina: R = 0.72, D = 51%, BA = 87% within range); paired cervix/vagina measurements showed moderate correlation only (R = 0.56; D = 31.3%). Standardized sample collection and simple modification of the Roche Cobas Amplicor HIV-1 Monitor assay allows reproducible measurement of genital viral load.


Asunto(s)
Genitales Femeninos/virología , Infecciones por VIH/virología , VIH-1/aislamiento & purificación , ARN Viral/análisis , Virología/métodos , Cuello del Útero/virología , Femenino , Humanos , Reproducibilidad de los Resultados , Útero/virología , Virología/instrumentación , Virología/estadística & datos numéricos
8.
J Acquir Immune Defic Syndr ; 30(2): 159-66, 2002 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-12045678

RESUMEN

BACKGROUND: In HIV-positive persons receiving antiretroviral therapy, CD4 cell responses are associated with optimal suppression of viral replication. However, increases in CD4 cell counts in the absence of viral suppression have been reported. We characterized plasma viral load (pVL) and CD4 cell count increases in closely followed patients to evaluate determinants and the prevalence of CD4 cell responses at a populational level. METHODS: All HIV-positive patients in the province of British Columbia, Canada, who were antiretroviral naive and initiated therapy between August 1996 and May 1998 were eligible for the study. The selection criteria were that patients had to have CD4 cell counts and pVLs measured at baseline and at least once during eight 16-week periods after the initiation of therapy. We characterized CD4 cell responses and sought patients who had a "discordant" increase at 1 year, which was defined as an increase in CD4 cell count of >or=50/mm3 with a <1 log10 decrease in pVL. We also evaluated adherence and antiretroviral use. RESULTS: Overall, when baseline and 1-year pVLs and CD4 cell counts were compared, 6.2% of patients had CD4 cell count increases without pVL decreases of >or=1 log10. However, when all pVLs before 1 year were considered, 92% of the discordant increases could be attributed to prior transient or partial viral suppression. Furthermore, although substantial increases in CD4 cell counts were observed in transient virologic responders, the cumulative number of antiretroviral agents used by this group was significantly higher than that used by full virologic responders (p <.001). CONCLUSIONS: Our results demonstrate that virtually all CD4 cell count increases can be attributed to transient or partial pVL suppression. Unmeasured pVL suppression likely explains discordant responses that have been previously reported. Similarities between transient and full virologic responders also appear to be time limited and are often associated with greater cumulative use of antiretroviral therapy by transient virologic responders.


Asunto(s)
Recuento de Linfocito CD4 , Infecciones por VIH/inmunología , Infecciones por VIH/virología , VIH-1/fisiología , Carga Viral , Adulto , Fármacos Anti-VIH/uso terapéutico , Quimioterapia Combinada , Femenino , Inhibidores de la Proteasa del VIH/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Vigilancia de la Población , ARN Viral/sangre , Inhibidores de la Transcriptasa Inversa/uso terapéutico , Viremia
9.
J Clin Microbiol ; 42(2): 800-6, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14766856

RESUMEN

The VERSANT hepatitis B virus (HBV) 3.0 Assay (branched DNA [bDNA]) (referred to herein as VERSANT 3.0) was evaluated at four external sites for analytical sensitivity, specificity, reproducibility, linearity of quantification, and limits of detection. In addition, each of the test evaluation sites provided HBV DNA-positive clinical samples that were previously analyzed by one of three commercially available HBV DNA quantitative tests: Digene Hybrid Capture II HBV DNA Test (Digene); VERSANT HBV DNA 1.0 Assay (bDNA) (VERSANT 1.0); and COBAS AMPLICOR HBV Monitor Test (COBAS AMPLICOR). These samples were reexamined using VERSANT 3.0. The results from these studies showed that VERSANT 3.0 has high specificity (99.3%), excellent reproducibility (between-run coefficient of variation [CV] = 1.6 to 9.4%; within-run CV = 6.5 to 20.7%), and a broad linear range of quantification (2.0 x 10(3) to 1.0 x 10(8) HBV DNA copies/ml) that facilitate the monitoring of HBV DNA levels at diagnosis and throughout the course of treatment. In general, correlation was very good between results obtained from clinical samples analyzed by VERSANT 3.0 and the comparative HBV DNA quantitative assays (VERSANT 1.0, R(2) = 0.900; Digene, R(2) = 0.985; COBAS AMPLICOR, R(2) = 0.771). The greatest differences in comparative quantitation occurred at HBV DNA levels approaching the limits of the dynamic ranges for the comparative assays. The performance characteristics of the new VERSANT 3.0 assay demonstrated that it provides a reliable and robust method for routinely monitoring serum HBV DNA levels in assessing disease activity and determining response to antiviral treatment.


Asunto(s)
ADN Viral/sangre , Virus de la Hepatitis B/genética , ADN Viral/genética , Técnicas Genéticas , Hepatitis B/diagnóstico , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
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