Correlation of serological and molecular markers in the screening for hepatitis B virus in blood bank in northern Brazil

ABSTRACT Introduction: In Brazil, the blood donor screening for hepatitis B virus (HBV) includes laboratory testing for serological (HBsAg and Anti-HBc) and molecular (HBV DNA) markers. This study aims to correlate serology reactive results with HBV DNA detection among blood donors with at least one HBV infection marker detected in a blood bank in northern Brazil. Method: A retrospective search for HBV reactive blood donor data from January 2017 to December 2019 was performed. Serological screening was performed by chemiluminescent microparticle immunoassays Architect HBsAg and Architect Anti-HBc, whereas molecular screening was performed by the HBV nucleic acid test (HBV NAT). Main results: A total of 556 HBsAg reactive results were detected, between positive (47.66%) and inconclusive (52.34%). A total of 3,658 Anti-HBc reactive results were detected, between positive (83.71%) and inconclusive (16.29%). None of the inconclusive results were associated with HBV DNA detection. The HBV DNA detection rates were 47.55% among HBsAg positive samples and 4.08% among Anti-HBc positive samples. The signal-to-cutoff (S/CO) ratio median of HBV NAT positive samples was superior in comparison to HBV NAT negative samples (p < 0.0001). The thresholds found to optimize sensitivity and specificity were 404.15 for Architect HBsAg and 7.77 for Architect Anti-HBc. Three blood donors were in the window period and 1 occult HBV infection case was detected. Conclusion: High S/CO ratios were more predictive of HBV DNA detection. However, a number of HBV NAT positive samples gave low values, while some HBV NAT negative samples showed high values, reaffirming the significance of molecular testing to enhance transfusion safety.

Thoughts on expert opinion on expanding antiviral therapy for chronic hepatitis B / 临床肝胆病杂志

Expanding antiviral therapy is currently the new trend for the diagnosis and treatment of chronic hepatitis B, and related research evidence should be studied and discussed. Reducing the threshold of alanine aminotransferase (ALT) for initiating antiviral therapy is one of the most important changes during the expansion of antiviral therapy. Chronic hepatitis B patients with a low-level increase in ALT or a high normal level of ALT still have a higher risk of liver cancer and thus require further intervention. At present, nucleos(t)ide analogues show a certain clinical effect in some patients in terms of virological inhibition and improvement in fibrosis, while reducing ALT threshold places higher requirements for biochemical response after treatment. In addition, although the mechanism and definition of low-level viremia (LLV) after treatment remain unclear, further intervention of LLV is an important strategy for optimizing patient management in clinical practice. Switch to another potent nucleos(t)ide analogue may improve the virologic response rate of patients with LLV, and nucleos(t)ide analogues combined with interferon or other new targeted drugs will be an important research direction for the treatment of LLV in the future.

Demographic characteristics and associated influencing factors in treated patients with chronic hepatitis B with hypoviremia : a single-center retrospective cross-sectional study / 中华肝脏病杂志

Objective: To investigate the demographic characteristics and clinical influencing factors which associates with the occurrence probability of persistent or intermittent hypoviremia (LLV) in patients with chronic hepatitis B (CHB) treated with nucleos(t)ide analogues (NAs). Methods: A single-center retrospective analysis was performed on patients with CHB who received outpatient NAs therapy for≥48 ± 2 weeks. According to the serum hepatitis B virus (HBV) DNA load at 48±2 weeks treatment, the study groups were divided into LLV (HBV DNA < 20 IU/ml and < 2 000 IU/ml) and MVR group (sustained virological response, HBV DNA < 20 IU/ml). Demographic characteristics and clinical data at the start of NAs treatment (considered as baseline) were retrospectively collected for both patient groups. The differences in the reduction of HBV DNA load during treatment was compared between the two groups. Correlation and multivariate analysis were further conducted to analyze the associated factors influencing the LLV occurrence. Statistical analysis was performed using the independent samples t-test, c2 test, Spearman analysis, multivariate logistic regression analysis, or area under the receiver operating characteristic curve. Results: A total of 509 cases were enrolled, with 189 and 320 in the LLV and MVR groups, respectively. Compared to patients with MVR group at baseline: (1) the demographics characteristics of patients showed that LLV group was younger in age (39.1 years, P = 0.027), had a stronger family history (60.3%, P = 0.001), 61.9% received ETV treatment, and higher proportion of compensated cirrhosis (20.6%, P = 0.025) at baseline; (2) the serum virological characteristics of patients showed that LLV group had higher HBV DNA load, qHBsAg level, qHBeAg level, HBeAg positive rate, and the proportion of genotype C HBV infection but decreased HBV DNA during treatment (P < 0.001) at baseline; (3) the biochemical characteristics of patients showed that LLV group had lower serum ALT levels (P = 0.007) at baseline; (4) the noninvasive fibrosis markers of patients showed that LLV group were characterized by high aspartate aminotransferase platelet ratio index (APRI) (P = 0.02) and FIB-4 (P = 0.027) at baseline. HBV DNA, qHBsAg and qHBeAg were positively correlated with LLV occurrence (r = 0.559, 0.344, 0.435, respectively), while age and HBV DNA reduction were negatively correlated (r = -0.098, -0.876, respectively). Logistic regression analysis showed that ETV treatment history, high HBV DNA load at baseline, high qHBsAg level, high qHBeAg level, HBeAg positive, low ALT and HBV DNA level were independent risk factors for patients with CHB who developed LLV with NAs treatment. Multivariate prediction model had a good predictive value for LLV occurrence [AUC 0.922 (95%CI: 0.897 ~ 0.946)]. Conclusion: In this study, 37.1% of CHB patients treated with first-line NAs has LLV. The formation of LLV is influenced by various factors. HBeAg positivity, genotype C HBV infection, high baseline HBV DNA load, high qHBsAg level, high qHBeAg level, high APRI or FIB-4 value, low baseline ALT level, reduced HBV DNA during treatment, concomitant family history, metabolic liver disease history, and age < 40 years old are potential risk factors for developing LLV in patients with CHB during the therapeutic process.

Analysis of peripheral blood lymphocyte status in low-level-viremia patients with chronic hepatitis B virus infection after nucleos(t)ide analogue treatment / 中华微生物学和免疫学杂志

Objective:To evaluate the status of T, B and NK lymphocytes in peripheral blood of patients with chronic hepatitis B virus(HBV) infection and low-level viremia after nucleos(t)ide analogue (NA) treatment and to provide ideas for solving low-level viremia.Methods:This retrospective study involved 344 patients with chronic HBV infection who had been treated with NAs. They were divided into two groups: low-level viremia group (LLV group) and complete virological response group (CVR group). Clinical data including basic information, biochemistry and coagulation test results, HBV DNA, peripheral blood lymphocyte counts, PD1 and CD28 expression by T lymphocytes, and perforin and granzyme B expression by NK lymphocytes were collected and compared between the two groups. Propensity matching analysis was performed to verify the accuracy of the results.Results:Among the 344 cases, 162 were in the LLV group and 182 in the CVR group. There were no significant differences in disease diagnosis, alanine aminotransferase (ALT), aspartate aminotransferase (AST) or albumin (ALB) level between the two groups ( P>0.05), but the differences in gender and age were statistically significant ( P<0.05). The differences in the counts and percentages of peripheral blood CD3 +, CD4 + and CD8 + T lymphocyte and CD4 + /CD8 + ratios between the two groups were not statistically significant ( P>0.05), but the expression of PD1 and CD28 by peripheral blood CD3 +, CD4 + and CD8 + T lymphocytes was higher in the LLV group than in the CVR group ( P<0.05). The count of peripheral blood CD19 + B lymphocytes in the LLV group was higher than that in the CVR group ( P>0.05), and the percentage of peripheral blood CD19 + B lymphocytes was also higher in the LLV group ( P<0.05). The count of peripheral blood CD16 + CD56 + NK lymphocytes and the expression of perforin in the LLV group were lower than those in the CVR group ( P>0.05). The percentage of peripheral blood CD16 + CD56 + NK lymphocytes and the expression of granzyme B in the LLV group were lower than those in the CVR group ( P<0.05). After propensity score matching, 108 cases in the LLV group and 108 cases in the CVR group showed no significant differences in basic information ( P>0.05); the percentage of CD4 + T lymphocytes and CD4 + /CD8 + ratio in peripheral blood T lymphocyte subsets were higher in the LLV group than in the CVR group, while the percentage of CD8 + lymphocytes was lower in the LLV group ( P<0.05); the expression of PD1 and CD28 by CD3 +, CD4 + and CD8 + T lymphocytes remained higher in the LLV group ( P<0.05); the differences in the counts and percentages of peripheral blood CD19 + B lymphocytes as well as CD16 + CD56 + NK lymphocytes between the two groups were not statistically significant ( P>0.05); no significant difference in the expression of perforin by CD16 + CD56 + NK lymphocytes was found between the two groups ( P>0.05), and the expression of granzyme B remained lower in the LLV group ( P<0.05). Conclusions:Abnormal number and function of T lymphocytes and decreased function of NK lymphocytes might be related to the development of LLV in patients with chronic HBV infection after treatment. Therefore, in addition to adjusting NAs, targeting of T and NK lymphocytes might also be a feasible measure for future LLV treatment.

Risk factors associated with low-level viremia in human immunodeficiency virus/acquired immunodeficiency syndrome patients after anti-retroviral therapy / 中华传染病杂志

Objective:To investigate the risk factors of low-level viremia (LLV) among human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) patients after combined anti-retroviral therapy (ART), and to provide evidence for reducing the risk of LLV.Methods:It was a cross-sectional observation study that enrolled HIV/AIDS patients with LLV (plasma HIV-1 RNA was 50 to 1 000 copies/mL) receiving ART over one year (LLV group) from January 2019 to December 2020 in Guangzhou Eighth People′s Hospital, Guangzhou Medical University. Contemporaneous patients with ART over one year and successful viral suppression (plasma HIV-1 RNA<50 copies/mL) were randomly selected as the control group (suppression group) with a ratio of 1∶2.5, and the risk factors for LLV were analyzed by unconditional logistic regression.Results:A total of 128 and 297 patients were enrolled in LLV group and the suppression group, respectively.ART durations were 3.62(1.83, 4.89) years and 4.91(2.90, 5.88) years, respectively. Multivariate logistic regression analysis showed that the risk factors associated with LLV included the age of initial ART treatment above 50 years old (odds ratio ( OR)=1.82, 95% confidence interval ( CI) 1.01 to 3.26, P=0.046), the baseline HIV-1 RNA over 1×10 5 copies/mL ( OR=2.18, 95% CI 1.30 to 3.68, P=0.003), using the simplified initial ART regimen ( OR=1.82, 95% CI 1.02 to 3.26, P=0.044), missing medication more than three times per year ( OR=2.49, 95% CI 1.55 to 4.01, P<0.001) and changing regimen during ART ( OR=1.90, 95% CI 1.14 to 3.14, P=0.013), while the duration of ART longer than five years could reduce the risk of LLV ( OR=0.37, 95% CI 0.22 to 0.64, P<0.001). In patients with simplified initial ART regimen, the baseline CD4 + T lymphocyte count of whom with LLV was lower than that of whom with viral suppression, and the difference was statistically significant (94.00 (24.00, 281.00)/μL vs 375.00 (310.00, 435.00)/μL, Z=-2.60, P<0.001). Conclusions:The occurrence of LLV is related to the age of initial ART treatment, the baseline HIV-1 RNA, the initial ART regimen, the medication adherence and the change of ART regimen during ART. Strategies may be beneficial to reducing the risk of LLV for HIV/AIDS patients, such as initiating ART as soon as possible, using simplified regimen as initial regimen with caution in patients with low baseline CD4 + T lymphocyte counts, strengthening compliance education, avoiding unnecessary ART regimen changes.

Clinical effect of tenofovir alafenamide fumarate on chronic hepatitis B patients with low viral load after entecavir treatment / 临床肝胆病杂志

Objective To investigate the clinical effect of tenofovir alafenamide fumarate (TAF) on chronic hepatitis B (CHB) patients with low-level viremia (LLV) after entecavir (ETV) treatment. Methods A total of 160 CHB patients who received ETV antiviral therapy in Wuhan Jinyintan Hospital from March 2019 to October 2020 were enrolled and divided into experimental group and control group by propensity score matching, with 80 patients in each group. The patients in the experimental group were given TAF antiviral therapy, and those in the control group were given ETV treatment; the course of treatment was 24 weeks for both groups. The two groups were compared in terms of HBV-DNA clearance rate, HBeAg clearance rate, alanine aminotransferase (ALT) level, estimated glomerular filtration rate (eGFR), FIB-4 value, liver stiffness measurement, and adverse drug reactions after treatment. The t -test was used for comparison of continuous data between two groups, and the chi-square test was used for comparison of categorical data between two groups. Results After 24 weeks of treatment, compared with the control group, the experimental group had significantly higher HBV DNA clearance rate (96.25% vs 16.25%, χ 2 =104.03, P 0.05). Conclusion For CHB patients with LLV after ETV treatment, the change to TAF antiviral therapy can effectively increase their HBV DNA clearance rate and HBeAg clearance rate, improve liver and renal function, and reduce the degree of liver fibrosis, with good safety.

Impact of low level viremia on the antiviral effect of human immunodeficiency virus/acquired immunodeficiency syndrome patients received anti-retroviral therapy / 中华传染病杂志

Objective:To investigate the impact of low level viremia (LLV) on the prognosis of human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) patients received anti-retroviral therapy (ART).Methods:From January to December 2015, the HIV/AIDS patients with LLV received ART over one year were recruited in Guangzhou Eighth People′s Hospital, Guangzhou Medical University (LLV group). Patients with viral load (VL) less than 50 copies/mL were matched at ratio of 1∶1 according to gender, age and the transmission route were included in the control group (suppression group). The LLV group was divided into three subgroups according to VL (LLV-1 subgroup was 50-200 copies/mL, LLV-2 subgroup was 201-400 copies/mL, and LLV-3 subgroup was 401-1 000 copies/mL). The influence of LLV on the antiviral response during the following three years was investigated.The Wilcoxon signed rank test, Kruskal-Wallis test and chi-square test were used for statistical analysis.Results:One hundred and thirty-seven patients were enrolled in the LLV group, of whom 111 were males and 26 were females, with age of (39.5±13.5) years old. At the same time, 137 patients were included in the suppression group. There were 93 cases in LLV-1 subgroup, 25 cases in LLV-2 subgroup and 19 cases in LLV-3 subgroup. There were no significant differences in the CD4 + T lymphocyte counts and CD4 + /CD8 + T lymphocyte counts ratios between LLV group and suppression group before ART (both P>0.05). During the three-year follow-up, the cumulative number of viral failures in LLV group (7.3%(10/137)) was significantly higher than that in the suppression group (1.5%(2/137)) ( χ2=5.578, P=0.018). Virological failure occurred in eight patients (8.6%) in the LLV-1 subgroup, two patients (8.0%) in the LLV-2 subgroup, and no patients in the LLV-3 subgroup. There was no statistical significance in the incidence of virological failure among all the subgroups ( P>0.05). At one, two, three years follow-up, the CD4 + T lymphocyte counts increased in both LLV group and suppression group without statistical differences (all P>0.05), and the CD4 + /CD8 + T lymphocyte counts ratios in each LLV group were lower than that in the suppression group ( Z=-3.183, -2.094 and -2.312, respectively, all P<0.05). At one, two, three years follow-up, There were no significant differences in CD4 + /CD8 + T lymphocyte counts ratios among the LLV-1, LLV-2 and LLV-3 subgroups (all P>0.05). Conclusion:HIV/AIDS patients with LLV having received ART over one year are more likely to develop virological failure and delay the recovery of immune function, which requires early relevant interventions.

Current status of the research on low-level viremia in chronic hepatitis B patients receiving nucleos(t)ide analogues / 临床肝胆病杂志

Nucleos(t)ide analogues (NAs), which are widely used as the first-line anti-hepatitis B virus (HBV) drugs in clinical practice, can effectively inhibit the replication of HBV DNA, significantly slow down disease progression in chronic hepatitis B (CHB) patients, and reduce the development of end-stage liver diseases such as liver failure and liver cancer. However, for some CHB patients receiving first-line NAs for 48 weeks or longer, serum HBV DNA is still persistently or intermittently higher than the lower detection of limit of sensitive nucleic acid detection reagents. After discussion by the authors, low-level viremia (LLV) is defined as follows: persistent LLV refers to the condition in which CHB patients, who receive entecavir, tenofovir disoproxil fumarate, or tenofovir alafenamide fumarate for ≥48 weeks, test positive for HBV DNA by two consecutive detections with sensitive quantitative PCR, with an interval of 3-6 months, but have an HBV DNA level of ＜2000 IU/ml; intermittent LLV refers to the condition in which patients test positive for HBV DNA intermittently by at least three consecutive detections with sensitive quantitative PCR, with an interval of 3-6 months, but have an HBV DNA level of ＜2000 IU/ml. For the diagnosis of LLV, the issues of poor compliance and drug-resistant mutations should be excluded. LLV might be associated with the increased risk of progression to liver fibrosis or hepatocellular carcinoma in patients with liver cirrhosis under NA treatment, but there are still controversies over whether the original treatment regimen with NAs should be changed after the onset of LLV. This article summarizes the incidence rate of LLV under NA treatment and the influence of LLV on prognosis and analyzes the possible mechanisms of the osnet of LLV, so as to provide a reference for the management of LLV in patients treated with NAs.

Analysis of risk factors of high-level BK viruria after renal transplantation / 器官移植

Objective To analyze the risk factors of high-level BK viruria after renal transplantation and the significance in preventing BK virus-associated nephropathy (BKVAN). Methods Clinical data of 262 renal transplant recipients with regular follow-up data were retrospectively analyzed. According to the DNA load of BK virus, all recipients were divided into the high-level BK viruria group (n=35) and non-high-level BK viruria group (n=227). The incidence of high-level BK viruria after renal transplantation was summarized. The risk factors of high-level BK viruria after renal transplantation were analyzed by univariate analysis and multivariate analysis. Survival curve was delineated by Kaplan-Meier method, and survival analysis of recipients was performed. Results Among 262 renal transplant recipients, 35 cases developed high-level BK viruria with an incidence of 13.4%. The median time of occurrence of high-level BK viruria was 181 (126, 315) d. The incidence was the highest within 6 months after renal transplantation, gradually decreased from 6 months to 2 years, and then increased after 2 years. Univariate analysis showed that the history of antithymocyte globulin (ATG) treatment, acute rejection (AR), donation type and delayed graft function (DGF) were the risk factors of high-level BK viruria after renal transplantation (all P < 0.05). Multivariate Cox regression analysis demonstrated that donation after brain death followed by cardiac death (DBCD), AR and DGF were the independent risk factors of high-level BK viruria after renal transplantation. The 1-, 3- and 5-year survival rates of recipients with ATG treatment history, AR, DGF and donation type of DBCD were significantly lower than those with non-ATG treatment history, non-AR, non-DGF and other donation types [donation after brain death (DBD), donation after cardiac death (DCD) and living organ donation] respectively (all P < 0.05). Conclusions DBCD, AR and DGF are the independent risk factors of high-level BK viruria after renal transplantation. Strengthening the postoperative monitoring of these recipients and delivering early intervention may effectively prevent BKVAN.

Influencing factors for low-level viremia in chronic hepatitis B patients treated with long-term entecavir antiviral therapy / 临床肝胆病杂志

ObjectiveTo investigate the influencing factors for persistent low-level viremia (LLV) in chronic hepatitis B(CHB) patients receiving long-term entecavir antiviral therapy. MethodsThe CHB patients who received entecavir antiviral therapy for at least one year in The Affiliated Hospital of Xuzhou Medical University from November 2018 to June 2020 were enrolled as subjects, and according to HBV DNA load at the end of the observation period, the patients were divided into LLV group and sustained virological response (SVR) group. Demographic features and laboratory markers were observed for all patients. The independent samples t-test or the Mann-Whitney U test was used for comparison of continuous data between two groups, and the chi-square test was used for comparison of categorical data between two groups. A multivariate logistic regression analysis was used to investigate the influencing factors for LLV in patients receiving long-term entecavir treatment. ResultsA total of 560 CHB patients were enrolled, with 204 in the LLV group and 356 in the SVR group. There were significant differences between the two groups in age (Z=-3.530, P＜0.001), sex (χ2=4.270, P=0.039), presence or absence of liver cirrhosis (χ2=53.879, P＜0.001), medication compliance (χ2=5.326, P=0.021), HBeAg positive rate (χ2=90.681, P＜0.001), baseline HBV DNA load before treatment (Z=-8.337, P＜0.001), baseline HBsAg quantification (Z=-10.472, P＜0.001), and medication type (χ2=7.558, P=0.006). The multivariate logistic regression analysis showed that baseline HBeAg status before treatment (odds ratio ［OR］=3.381, 95% confidence interval ［CI］: 1.985-5.756, P＜0.001), HBV DNA load before treatment (OR=1.223, 95%CI: 1.050-1.424, P=0.010), and HBsAg quantification before treatment (OR=2.448, 95%CI: 1.743-3.438, P＜0.001) were risk factors for LLV in long-term entecavir antiviral therapy. ConclusionIn clinical practice, CHB patients with high HBV DNA load, high HBsAg quantification, and positive HBeAg tend to have a high risk of LLV even after long-term entecavir antiviral therapy. Therefore, such population should be taken seriously with the dynamic monitoring of HBsAg quantification, HBV DNA load, and HBeAg status.

Zika virus infection and transfusion safety / 中国输血杂志

Zika virus(ZIKV) is an arbovirus transmitted mainly by mosquitoes. ZIKV infection usually causes mild self-limiting disease, and most of the infected patients only developed relatively mild symptoms which were often easily overlooked. However, serious damage of the central nervous system is observed in a few of the infected patients, and microcephaly of embryos and fetuses in pregnant women infected by ZIKV has attracted wide attention in recent years. Although there is a high proportion of asymptomatic infection and a high incidence of viremia, ZIKV has not been included in the routine pathogen screening before blood donation in China yet, and there is a risk of transmission through blood transfusion. This article briefly introduces the biological characteristics, epidemic characteristics, and pathogenic mechanisms of ZIKV,, and discusses ZIKV infection and the safety of blood transfusion.

SARS-CoV-2 viremia may predict rapid deterioration of COVID-19 patients

ABSTRACT COVID-19 has raised worldwide concern as spiraling into a pandemic. Reports about comprehensive investigation of COVID-19 viremia are extremely scanty. Herein, we present four COVID-19 patients with positive SARS-CoV-2 nucleic acid test in blood, accounting for 12.12% of 33 detected cases. Rapid deterioration of these cases with septic shock, accompanying with lung CT images enlarged rapidly, decrease of blood oxygen, heart rate drop (with asynchrony of hypoxemia) accompanied with SARS-CoV-2 viremia. It indicates that massive replication and releasing into blood of SARS-CoV-2 and secondary inflammation storm may lead to injury of multiple organs and poor prognosis. So, positive COVID-19 nucleic acid test in blood may be a good forecasting marker of rapid deterioration of COVID-19 pneumonia. In addition, clearance of viremia may indicate tendency for recovery.

Impacto de la viremia de bajo grado en el riesgo de fallo virológico en pacientes con infección por VIH-1 / Impact of low-grade viremia on the risk of virological failure in patients with HIV-1 infection on antiretroviral therapy

Resumen Introducción: Cargas virales (CV) entre 20-200 copias/mL se consideran cargas virales de bajo grado (CVBG). Su implicancia clínica y manejo no han sido definidos. Objetivo: Evaluar el impacto de CVBG en el riesgo de desarrollo posterior de fallo virológico (FV). Pacientes y Métodos: Se incluyeron pacientes ≥ 18 años, desde enero de 2009 a diciembre de 2019, con infección por VIH-1 con CV< 20 copias/mL, por un mínimo de seis meses y/o en dos muestras consecutivas bajo tratamiento anti-retroviral . Se realizó seguimiento de las CV estrati ficándolas: CV < 20 copias/mL, CVBG (20-50 copias/mL y 51-200 copias/mL) y FV. Mediana de seguimiento 25 meses (IQR 15-31). Resultados: Fueron incluidos 1.416 pacientes con CV < 20 copias/ mL bajo TARV. De ellos, 797 permanecieron con CV< 20 copias/mL durante el seguimiento, 144 presentaron CV entre 20-50 copias/mL, 384 entre 51-200 copias/mL y 91 presentaron FV sin CVBG previa. De los 528 pacientes que tuvieron CVBG, 110 (20,1%) fallaron, riesgo 3,45 veces superior respecto a los que no tuvieron CVBG previa. El riesgo de FV fue 3,27 mayor para aquellos que tuvieron CVBG entre 51-200 copias/mL vs 20-50 copias/mL. Discusión: El estudio permite relacionar la CVBG con el FV posterior, siendo el mayor riesgo CVBG entre 51-200 copias/mL.

Abstract Background: Viral loads (VL) between 20-200 copies/mL are considered low-grade viral loads (LGVL). Its clinical implications and management have not been defined. Aim: To evaluate the impact of LGVL on the risk of subsequent development of virological failure (VF). Methods: Patients ≥ 18 years, with HIV-1 infection who had VL < 20 copies/mL for at least six months and/or in two consecutive samples under antiretroviral therapy (ART) were included, between January 1st, 2009 and December 31, 2019. Follow-up of the VLs was carried out stratifying them in VL < 20 copies/mL, LGVL (20-50 copies/mL and 51-200 copies/mL) and VF. Median follow-up 25 months (IQR 15-31). Results: 1,416 patients were included who reached VL < 20 copies/ml under ART, 797 patients remained with CV < 20 copies/mL during follow-up, 144 patients had VL between 21-50 copies/mL, 384 between 51-200 copies/mL and 91 had VF without previous LGVL. Out of 528 patients who had LGVL, 110 failed, risk 3.45 times higher than those who had no previous LGVL. Risk 3.27 times higher of VF for those who had LGVL between 51-200 copies/mL compared to 20-50 copies/mL. Discussion: The study allows to relate the LGVL with VF. This association was observed more frequently with LGVL between 51-200 copies/mL

Hepatitis B viremia in HIV-coinfected individuals under antiretroviral therapy

ABSTRACT Background: Antiretroviral therapy (ART) has decreased AIDS incidence and mortality, rendering comorbidities, such as hepatitis B more relevant for people living with human immunodeficiency virus (HIV). Since antiretroviral drugs may also inhibit hepatitis B virus (HBV) replication, analyzing the impact of ART on management of hepatitis B in this population is important. Objective: To assess HBV viremia among HIV/HBV coinfected individuals on ART and its associated factors. Method: For this cross-sectional study, HIV/HBV-coinfected individuals, aged over 18 years, who were on ART for over six months and receiving care at an outpatient clinic in São Paulo were recruited. Sociodemographic characteristics, information about viral exposure, clinical and laboratory data, including evaluation of liver fibrosis were obtained. Plasma HBV DNA was measured by polymerase chain reaction. Viral genome sequencing was conducted for genotyping and identification of drug resistance-conferring mutations if viral load exceeded 900 IU/mL. Results: Out of 2,946 patients who attended the clinic in 2015, 83 were eligible and 56 evaluated. Plasma HBV DNA was detected in 16 (28.6%) (95% CI: 18.0-41.3%), all on lamivudine and tenofovir treatment. HBV DNA detection was associated with lower education (p = 0.015), higher international normalized ratios (p = 0.045), history of an AIDS-defining illness [OR: 3.43 (95% CI: 1.10-11.50)], and HBeAg detection [OR: 6.60 (95% CI: 1.84-23.6)]. In contrast, a last CD4+ count above 500 cells/mm3 in the year prior to inclusion [OR: 0.18 (95% CI: 0.04-0.71)] and detection of anti-HBe [OR: 0.21 (95% CI: 0.04-0.99)] were negatively associated. Patients with HBV DNA above 900 IU/mL were infected with subgenotypes A1 (n = 3) and D2 (n = 1), and exhibited viral mutations associated with total resistance to lamivudine and partial resistance to entecavir. Conclusions: Despite being on ART, a significant proportion of HIV/HBV-coinfected individuals present HBV viremia. Characterization of factors that are associated with this finding may help professionals provide better management to these patients.

IgG1 and IgG4 antibodies against core and NS3 antigens of hepatitis C virus

Abstract INTRODUCTION: IgG subclasses involved in the immune response to hepatitis C virus (HCV) antigens have been rarely studied. We investigated the immune response mediated by IgG1 and IgG4 antibodies against the recombinant core and NS3 antigens in patients with chronic hepatitis C. METHODS: Sixty patients infected with HCV genotype 1 without antiviral treatment and 60 healthy subjects participated in the study. Serum levels of alanine aminotransferase, HCV viremia, and the presence of cryoglobulinemia and liver fibrosis were determined. We investigated the serum IgG1 and IgG4 antibodies against recombinant HCV core and NS3 non-structural protein antigens using amplified indirect ELISA. RESULTS: Anti-core and anti-NS3 IgG1 antibodies were detected in 33/60 (55%) and 46/60 (77%) patients, respectively, whereas only two healthy control samples reacted with an antigen (NS3). Anti-core IgG4 antibodies were not detected in either group, while 30/60 (50%) patients had anti-NS3 IgG4 antibodies. Even though there were higher levels of anti-NS3 IgG4 antibodies in patients with low viremia (< 8 × 105 IU/mL), IgG1 and IgG4 antibody levels did not correlate with ALT levels, the presence of cryoglobulinemia, or degree of hepatic fibrosis. High production of anti-core and anti-NS3 IgG1 antibodies was observed in chronic hepatitis C patients. In contrast, IgG4 antibodies seemed to only be produced against the NS3 non-structural antigen and appeared to be involved in viremia control. CONCLUSIONS: IgG1 antibodies against structural and non-structural antigens can be detected in chronic hepatitis C, while IgG4 antibodies seem to be selectively stimulated by non-structural HCV proteins, such as the NS3 antigen.

Association of serum levels of C-reactive protein with CRP-717 T/C polymorphism and viremia in HCV and HBV carriers

Abstract INTRODUCTION: The present study investigated the association of the rs2794521 polymorphism in the CRP gene in individuals with chronic hepatitis B and C, correlating it with markers of hepatic inflammation, fibrosis scores, viral load, and plasma protein levels. METHODS: The study analyzed 185 blood samples obtained from patients with hepatitis B (n=74) and hepatitis C (n=111) and 300 samples from healthy donors. Genotyping was performed by real-time polymerase chain reaction, and protein levels were quantified using the automated immunoturbidimetric method. RESULTS: The TT genotype was the most frequent in all studied groups and was associated with higher plasma levels of the protein but not with the progression of liver disease. Low levels of C-reactive protein were associated with increased viremia and scores indicative of severe fibrosis and cirrhosis. CONCLUSIONS: The present results demonstrated a close relationship between the ability of the virus to replicate and cause liver damage and low serum concentrations of C-reactive protein. Future research may determine if these results can be interpreted as a possible form of escape for the virus by decreasing its action as an opsonin and decreasing phagocytosis, which are functions of C-reactive protein in the immune response.

Viremia en plasma como factor asociado a gravedad en la infección por el virus del dengue: revisión sistemática de la literatura / Plasma viraemia as a factor associated to severity in dengue virus infection: systematic review of literature

Resumen Introducción: La viremia plasmática es un factor cuyo rol en la gravedad de la infección por el virus del dengue se ha discutido ampliamente en los últimos años, siendo hallados resultados divergentes en los múltiples contextos evaluados. Métodos: Se realizó una revisión sistemática de la literatura utilizando las bases de datos Scopus, EBSCOhost, SpringerLink, Lilacs y Scielo. Se consideraron para su inclusión en la revisión estudios que evaluaran la relación entre la carga viral en plasma y las manifestaciones clínicas o la gravedad de la enfermedad. Resultados: Se obtuvieron 80 referencias en la búsqueda inicial, posterior a la aplicación de los criterios de inclusión/exclusión fueron seleccionados 20 artículos. En el estudio de este fenómeno son múltiples los parámetros desde los cuales debe ser evaluada la viremia, no sólo desde su magnitud, sino también desde su duración post-defervescencia y el día en el que se reporta el valor máximo, entre otros. Discusión: Los resultados de los estudios indican que las características de la viremia pueden jugar un rol de importancia que, junto con otros factores del contexto viral (serotipo del virus, tipo de infección) y del paciente (edad, genotipo, comorbilidades, etc), pueden determinar el desenlace clínico de la infección.

Background: Plasma viremia is a factor whose role in the severity of dengue virus infection has been widely discussed in recent years, with divergent results found in the multiple contexts evaluated. Methods: A systematic review of the literature using the Scopus, EBSCOhost, SpringerLink, Lilacs and Scielo databases was conducted. For inclusion in the review there were considered studies that evaluated the relationship between plasma viral load and clinical manifestations or severity of the disease. Results: We obtained 80 references in the initial search, after the application of the inclusion / exclusion criteria 20 articles were selected. In the study of this phenomenon there are multiple parameters from which viremia should be evaluated, not only from its magnitude, but also from the post-defervescence duration and the day in which the maximum value is reported, among others. Discussion: The results of the studies indicate that the characteristics of viremia may play an important role that, along with other factors of the viral (virus serotype, type of infection) and patient context (age, genotype, comorbidities, etc.), determine the clinical outcome of the infection.

Quantitative detection of BK virus in kidney transplant recipients: a prospective validation study / Detecção quantitativa de vírus BK em receptores de transplante renal: um estudo prospectivo de validação

Abstract Introduction: BK virus (BKV) infection in renal transplant patients may cause kidney allograft dysfunction and graft loss. Accurate determination of BKV viral load is critical to prevent BKV-associated nephropathy (BKVAN) but the cut-off that best predicts BKVAN remains controversial. Objective: To evaluate the performance of a commercial and an in-house qPCR test for quantitative detection of BK virus in kidney transplant recipients. Methods: This was a prospective study with kidney transplant recipients from two large university hospitals in Brazil. Patients were screened for BKV infection every 3 months in the first year post-transplant with a commercial and an in-house real time polymerase chain reaction (qPCR) test. BKVAN was confirmed based on histopathology. The area under the curve for plasma qPCR was determined from receiver operating characteristic analysis. Results: A total of 200 patients were enrolled. Fifty-eight percent were male, 19.5% had diabetes mellitus, and 82% had the kidney transplanted from a deceased donor. BKV viremia was detected in 32.5% and BKVAN was diagnosed in 8 patients (4%). BKVAN was associated with viremia of 4.1 log copies/mL, using a commercial kit. The cut-off for the in-house assay was 6.1 log copies/mL. The linearity between the commercial kit and the in-house assay was R2=0.83. Conclusion: Our study shows that marked variability occurs in BKV viral load when different qPCR methodologies are used. The in-house qPCR assay proved clinically useful, a cheaper option in comparison to commercial qPCR kits. There is an urgent need to make BKV standards available to the international community.

Resumo Introdução: A infecção pelo vírus BK (BKV) em pacientes de transplante renal pode levar a disfunção do aloenxerto renal e perda do enxerto. A determinação precisa da carga viral do BKV é fundamental para prevenir a nefropatia associada ao BKV (BKVAN), mas o ponto de corte de melhor valor preditivo para BKVAN ainda é foco de debates. Objetivo: Avaliar o desempenho de um teste de qPCR comercial e outro desenvolvido internamente para detecção quantitativa de vírus BK em receptores de transplante renal. Métodos: O presente estudo prospectivo incluiu receptores de transplante renal de dois grandes hospitais universitários no Brasil. Os pacientes foram testados para infecção por BKV a cada três meses no primeiro ano pós-transplante com um teste comercial de reação em cadeia de polimerase quantitativa em tempo real (qPCR) e outro desenvolvido internamente. A presença de BKVAN foi confirmada com base na histopatologia. A área sob a curva para o qPCR plasmático foi determinada a partir da análise da característica de operação do receptor. Resultados: Um total de 200 pacientes foram incluídos. Cinquenta e oito por cento eram do sexo masculino, 19,5% tinham diabetes mellitus e 82% tiveram seus rins transplantados de doadores falecidos. Viremia de BKV foi detectada em 32,5% dos pacientes e oito (4%) foram diagnosticados com BKVAN. BKVAN foi associada a viremia de 4,1 log cópias/mL usando o kit comercial. O corte para o ensaio interno foi de 6,1 log cópias/mL. A linearidade entre o kit comercial e o ensaio interno foi R2 = 0,83. Conclusão: Nosso estudo demonstrou uma acentuada variabilidade na carga viral de BKV quando diferentes metodologias de qPCR foram utilizadas. O ensaio interno de qPCR mostrou-se clinicamente útil, além de ser uma opção menos onerosa em relação aos kits comerciais de qPCR. Há uma necessidade urgente de se definir padrões de BKV para a comunidade internacional.

Pp65 antigenemia and cytomegalovirus diagnosis in patients with lupus nephritis: report of a series / Antigenemia pp65 e diagnóstico de citomegalovírus em pacientes com nefrite lúpica: série de casos

ABSTRACT Introduction: In contrast to organ transplantation, few studies correlate the monitoring of pp65 antigenemia with a diagnosis of cytomegalovirus (CMV) in patients with systemic lupus erythematosus (SLE). Objective: To highlight the importance of CMV outside transplantation, we monitored pp65 antigenemia in a series of SLE patients. Methods: From March 2015 to March 2016, SLE patients presenting kidney involvement, fever, and an unclear infection at hospital admission were monitored through pp65 antigenemia. The pp65 antigenemia assay, revealed by immunofluorescence, was correlated with clinical and laboratory findings. Results: We included 19 patients with a suspected unclear infection. A positivity for pp65 antigenemia was found in seven patients (36.8%). The mean age was 33.5 ± 11.2 years, 16 (84%) were females, and 16 (84%) were black. Lymphopenia, anemia, and higher scores of SLEDAI were significantly more common in pp65-positive patients. Five patients received antiviral therapy with ganciclovir. Although receiving specific CMV treatment, one patient died because of suspected CMV disease. Conclusions: Pp65 antigenemia might be relevant in SLE patients, and studies with a greater number of patients are needed in order to establish sensitivity and specificity of pp65 antigenemia in different clinical contexts of SLE patients.

RESUMO Introdução: Diferentemente do transplante de órgãos, poucos estudos correlacionam o monitoramento da antigenemia pp65 com o diagnóstico de citomegalovírus (CMV) em pacientes com lúpus eritematoso sistêmico (LES). Objetivo: De modo a destacar a importância do CMV para além do transplante, monitorizamos a antigenemia pp65 em uma série de pacientes com LES. Métodos: De março de 2015 a março de 2016, pacientes com LES que apresentaram acometimento renal, febre e infecção indeterminada na internação foram monitorados através da antigenemia pp65. O ensaio de antigenemia, revelada por imunofluorescência, foi correlacionado com achado clínicos e laboratoriais. Resultados: Foram incluídos 19 pacientes com suspeita de infecção indeterminada. Positividade para antigenemia pp65 foi encontrada em sete pacientes (36,8%). A idade média foi de 33,5 ± 11,2 anos; 16 (84%) eram do sexo feminino e 16 (84%) eram negros. Linfopenia, anemia e escore de SLEDAI mais elevado foram significativamente mais comuns em pacientes pp65 positivos. Cinco pacientes receberam terapia antiviral com ganciclovir. Apesar de receber tratamento específico para CMV, um paciente com suspeita de doença por CMV veio a óbito. Conclusões: Antigenemia pp65 pode ser relevante em pacientes com LES, e estudos com maior número de pacientes são necessários para estabelecer a sensibilidade e a especificidade da antigenemia pp65 em diferentes contextos clínicos envolvendo pacientes com LES.

Analysis of swine leukocyte antigen class I gene profiles and porcine endogenous retrovirus viremia level in a transgenic porcine herd inbred for xenotransplantation research

Molecular characterization of swine leukocyte antigen (SLA) genes is important for elucidating the immune responses between swine-donor and human-recipient in xenotransplantation. Examination of associations between alleles of SLA class I genes, type of pig genetic modification, porcine endogenous retrovirus (PERV) viral titer, and PERV subtypes may shed light on the nature of xenograft acceptance or rejection and the safety of xenotransplantation. No significant difference in PERV gag RNA level between transgenic and non-transgenic pigs was noted; likewise, the type of applied transgene had no impact on PERV viremia. SLA-1 gene profile type may correspond with PERV level in blood and thereby influence infectiveness. Screening of pigs should provide selection of animals with low PERV expression and exclusion of specimens with PERV-C in the genome due to possible recombination between A and C subtypes, which may lead to autoinfection. Presence of PERV-C integrated in the genome was detected in 31.25% of specimens, but statistically significant increased viremia in specimens with PERV-C was not observed. There is a need for multidirectional molecular characterization (SLA typing, viremia estimation, and PERV subtype screening) of animals intended for xenotransplantation research in the interest of xeno-recipient safety.