Intrathecal production of anti-Epstein-Barr virus viral capsid antigen IgG is associated with neurocognition and tau proteins in people with HIV

OBJECTIVE

HIV and Epstein-Barr virus (EBV) co-infection has been linked to increased immune activation and larger HIV reservoir. We assessed whether anti-EBV humoral responses are associated with increased cerebrospinal fluid (CSF) inflammation and with neurocognitive impairment (NCI) in people with HIV (PWH).

DESIGN

Cross-sectional analysis in 123 EBV-seropositive PWH either on antiretroviral therapy ( n  = 70) or not.

METHODS

Serum and CSF anti-EBV viral capsid antigen immunoglobulin G (anti-EVI) and CSF EBV DNA were measured by commercial immunoassay and RT-PCR. Seventy-eight participants without neurological confounding factors underwent neurocognitive assessment (Global Deficit Score, GDS). CSF total tau and 181-phosphorylated-tau (ptau) were measured by immunoassays together with biomarkers of blood-brain barrier (BBB) integrity, immune activation, astrocytosis, and intrathecal synthesis. Logistic and linear regressions and moderation analysis were used to investigate the relationships between CSF anti-EVI, GDS, and biomarkers.

RESULTS

Twenty-one (17.1%) and 22 participants (17.9%) had detectable CSF anti-EVI (10.5-416.0 U/ml) and CSF EBV DNA (25-971 copies/ml). After adjusting for BBB integrity, age, and clinical factors, the presence of CSF anti-EVI was only associated with serum levels of anti-EVI, and not with CSF EBV DNA. CSF anti-EVI, tau and ptau showed reciprocal interactions affecting their associations with GDS. After adjusting for demographics and clinical parameters, higher CSF anti-EVI levels were associated with worse GDS (aβ 0.45, P  < 0.001), and CSF levels of tau and ptau had a moderation effect on the strength of this association (models' P  < 0.001).

CONCLUSION

Humoral immune responses against EBV within the central nervous system may contribute to NCI in PWH through mechanisms that involve neuronal injury.

Favorable experience of transplant strategy including liver grafts from COVID-19 donors: One-year follow-up results

BACKGROUND

Since November 2020, Italy was the first country to carry out a protocol and use liver from COVID-19 donors. We aimed to evaluate the medium-term outcome of patients who underwent liver transplant (LT) with those grafts.

METHODS

We consecutively enrolled 283 patients who underwent first LT from November 2020 to December 2022 in our Center (follow-up 468 days). Twenty-five of 283 (8.8%, study population) received a graft from donors with previous (4%) or active (96%) SARS-CoV-2 infection, and 258/283 (91.2%, control group) received a graft from COVID-19-negative donors. SARS-CoV-2-RNA was tested on graft tissue of COVID-19 donors and their recipients underwent weekly evaluation of SARS-CoV-2-RNA in nasal swabs for the first month after LT.

RESULTS

One-year and 2-year patient survival was 88.5% and 88.5% in study group versus 94.5% and 93.5% in control group, respectively (p = .531). In study population there was no evidence of donor-recipient virus transmission, but three (12%) patients (vs. 7 [2.7%] of control group, p = .048) developed hepatic artery thrombosis (HAT): they were SARS-CoV-2-RNA negative at LT and 1/3 grafts tested SARS-CoV-2-RNA positive on liver tissue. COVID-19 donor was independently associated with HAT (odds ratio (OR) = 4.85, 95% confidence interval (CI) 1.10-19.15; p = .037). By comparing study population with control group, acute rejection and biliary complication rates were not significantly different (16% vs. 8.1%, p = .26; 16% vs. 16.3% p = .99, respectively).

CONCLUSIONS

Our 1-year results of transplant strategy including liver grafts from COVID-19 donors were favorable. HAT was the only complication with significantly higher rate in patients transplanted with COVID-19 donors compared with control group.

Seroprevalence of hepatitis E virus in liver transplant patients in Turin, Italy

BACKGROUND

Acute E hepatitis is usually a self-limited non-progressive disease; however, acute liver failure and death can occur in the presence of conditions such as pregnancy and chronic liver diseases. In immunocompromised individuals, such as transplant patients, acute hepatitis E virus (HEV) infection may evolve to chronic hepatitis with rapid progression to liver decompensation. At our center, serology for HEV is not routinely performed in transplant patients and serological status is investigated only based on clinical judgement.

METHODS

In this study, seroprevalence of HEV was evaluated in 217 patients (120 liver transplant recipients and 97 individuals diagnosed with acute or chronic hepatitis). Molecular evaluation of HEV-RNA was also performed.

RESULTS

Thirteen patients (6%) showed positivity for HEV-IgG; in particular, 10/120 (8.3%), with concomitant presence of IgM and IgG in six and 3/97 (3.1%). None of the plasma samples tested by HEV-RNA was positive.

CONCLUSIONS

As the detectable RNA window is narrow and an undetectable HEV-RNA result does not exclude recent infection and the transplant context per se represents a risk factor for chronic infection in patients infected with HEV, a routine diagnostic workflow including HEV should be taken into consideration, increasing awareness and knowledge of the basic and clinical aspects of the disease.

Convalescent or standard plasma versus standard of care in the treatment of COVID-19 patients with respiratory impairment: short and long-term effects. A three-arm randomized controlled clinical trial

BACKGROUND

The efficacy of early treatment with convalescent plasma in patients with COVID-19 is debated. Nothing is known about the potential effect of other plasma components other than anti-SARS-CoV-2 antibodies.

METHODS

To determine whether convalescent or standard plasma would improve outcomes for adults in early phase of Covid19 respiratory impairment we designed this randomized, three-arms, clinical trial (PLACO COVID) blinded on interventional arms that was conducted from June 2020 to August 2021. It was a multicentric trial at 19 Italian hospitals. We enrolled 180 hospitalized adult patients with COVID-19 pneumonia within 5 days from the onset of respiratory distress. Patients were randomly assigned in a 1:1:1 ratio to standard of care (n = 60) or standard of care + three units of standard plasma (n = 60) or standard of care + three units of high-titre convalescent plasma (n = 60) administered on days 1, 3, 5 after randomization. Primary outcome was 30-days mortality. Secondary outcomes were: incidence of mechanical ventilation or death at day 30, 6-month mortality, proportion of days with mechanical ventilation on total length of hospital stay, IgG anti-SARS-CoV-2 seroconversion, viral clearance from plasma and respiratory tract samples, and variations in Sequential Organ Failure Assessment score. The trial was analysed according to the intention-to-treat principle.

RESULTS

180 patients (133/180 [73.9%] males, mean age 66.6 years [IQR 57-73]) were enrolled a median of 8 days from onset of symptoms. At enrollment, 88.9% of patients showed moderate/severe respiratory failure. 30-days mortality was 20% in Control arm, 23% in Convalescent (risk ratio [RR] 1.13; 95% confidence interval [CI], 0.61-2.13, P = 0.694) and 25% in Standard plasma (RR 1.23; 95%CI, 0.63-2.37, P = 0.544). Time to viral clearance from respiratory tract was 21 days for Convalescent, 28 for Standard plasma and 23 in Control arm but differences were not statistically significant. No differences for other secondary endpoints were seen in the three arms. Serious adverse events were reported in 1.7%, 3.3% and 5% of patients in Control, Standard and Convalescent plasma arms respectively.

CONCLUSIONS

Neither high-titer Convalescent nor Standard plasma improve outcomes of COVID-19 patients with acute respiratory failure. Trial Registration Clinicaltrials.gov Identifier: NCT04428021. First posted: 11/06/2020.

Impact of COVID-19 Infection, Vaccination, and Serological Response in Immune Thrombocytopenic Purpura Patients: A Single-Center Global Analysis

Both SARS-CoV-2 infection and vaccination have raised concern in immune-mediated diseases, including immune thrombocytopenic purpura (ITP) considering risk of de novo ITP development and ITP recurrence. Here, we report on data from a single-center retrospective-prospective collection aiming to evaluate platelet (plt) dynamics in patients (pts) with chronic ITP after COVID-19 infection (before and after vaccination) and after the first, second and third vaccine doses. Furthermore, we analyzed the serological response after the first two doses of COVID-19 vaccination. A total of 64 pts currently followed for chronic ITP who experienced COVD-19 infection and/or vaccination with an available plt count before and after such events were included in the analysis. A low incidence of ITP exacerbation following vaccine sessions (6-16%) was observed in comparison with a high frequency of exacerbation and rescue treatment necessity after COVID-19 infection in unvaccinated pts (83%). Moreover, the lower ITP exacerbation rate observed in infected pts previously vaccinated (18%) suggests further protective effects in this population. Finally, a high seroconversion rate was observed, confirming data reported in previously published studies on immune cytopenia and rheumatological diseases, but more evidence is awaited to establish the clinical impact of serological response.

Immune Response of a Heterologous mRNA-1273 Second-Dose Immunization after a First Dose of ChadOx1 against SARS-CoV-2: A Cross-Sectional Study

Heterologous vaccination regimens could contribute to broadening vaccination coverage. To date, there is little evidence on the effectiveness of a combination of adenoviral COVID-19 vaccines with a second dose of mRNA vaccines. This study aims to evaluate the antibody response to the SARS-CoV-2 spike protein 25 weeks after vaccination with mRNA-1273 after a first dose of ChAdOx1. A cross-sectional study was conducted collecting sociodemographic data, clinical characteristics, and serological data from among the general population. Antibody levels were expressed as binding antibody units (BAU) per mL (cutoff = 33.8 BAU/mL). Linear regression models were used to assess the relationship between the subjects’ characteristics and anti-SARS-CoV-2 antibody levels. A total of 229 participants were followed up after a median time of 173 days. The overall anti-SARS-CoV-2 IgG antibody titer was 729.0 BAU/mL. The multivariable analysis showed that the only factor associated with anti-SARS-CoV-2 IgG levels was the BMI (p = 0.007), with decreases within the healthy range weight and increases in under- or overweight people. Our results support the use of heterologous COVID-19 vaccination regimens, as they can guarantee a sustained immune antibody response. More studies are needed to understand the link between BMI and body composition and the immune response to COVID-19 vaccinations.

Seroconversion After Coronavirus Disease 2019 Vaccination in Patients Awaiting Liver Transplantation: Fact or Fancy?

Chronic liver disease increased the risk of severe coronavirus disease 2019 (COVID-19). Trials to assess efficacy/safety of COVID-19 vaccines in liver disease are underway. We evaluated the humoral immune response and safety of anti-COVID-19 vaccination among patients waiting liver transplantation (LT). We enrolled all pre-LT adults who completed anti-COVID-19 vaccination between January 2021-August 2021 as study group. Patients with histories of COVID-19 received 1 vaccine dose, and all others received 2 doses. Patients were tested for COVID-19 immunoglobulin G (IgG) within 1 and 2 months after vaccination. Safety was evaluated with telephone interviews/outpatient visits. A control group of 30 healthcare workers who underwent vaccination in January 2021 and tested for IgG after 4 months was included. In the 89 pre-LT patients, at T1 (23 days after vaccination), seroconversion rate was 94.4%, and median IgG value was 1980 binding antibody units/mL (interquartile range 646-2080), and at T2 (68 days after vaccination) was 92.0%, with IgG value of 1450 (577-2080); (T1 versus T2, P = 0.38). In the 10/89 patients who received 1 vaccine dose, the median IgG value was 274 (68-548) before vaccine (T0), 2080 (1165-2080) at T1, and 2030 (964-2080) at T2 (T0 versus T1, P = 0.03; T1 versus T2, P = 0.99). All controls tested positive at 4 months after vaccination, with a median value of 847 (509-1165; P < 0.001 versus T1 and P = 0.04 versus T2 in the study group). No serious adverse event was reported in both groups. Our data from 89 pre-LT patients suggest a high rate of immunization (94.4%) after a median time of 23 days from safe COVID-19 vaccine. None of the patients developed COVID-19.

Rubella serosurvey and factors related to vaccine hesitancy in childbearing women in Italy

Voluntary termination of pregnancy (VTP), pre-conception and post-partum phases, as well as Occupational Medicine consultation for healthcare workers are opportunities for screening and vaccinating rubella seronegative childbearing women. However, data about vaccination acceptance following these phases is rarely reported. A retrospective study over a 2-year period (2016-2017) was performed, evaluating the prevalence of rubella seronegative women which underwent VTP (wVTP), mothers in early puerperal phase (mEPP) and childbearing healthcare workers (CbHW) aged 15-49 years. Anti-rubella vaccination rates and factors associated with vaccine hesitancy (VH) were investigated. Anti-rubella IgG titres were assessed in 8623 women. Seroprevalence of rubella susceptibility was 7.9% (wVTP 6.4%; mEPP 17.4%; CbHW 9.3%). Anti-rubella vaccination rates were found to be different in the three groups (wVTP 37.1%; mEPP 10.9%; CbHW 25.4%), specifically in 2016 and among women born in Italy. VH rate was higher in 2017, especially among wVTP and CbHW. Anti-rubella vaccination rates in wVTP vs. mEPP was higher in women born in Italy but not in those born abroad. Multivariable analyses demonstrated significantly higher risk of VH for mEPP (OR 8.2; 95% CI: 3.9-16.9) and women reporting history of allergy to drugs, food or environmental agents (OR 2.7; 95% CI: 1.4-5.1). During the analyzed period childbearing women included in this study were not adequately protected against rubella. Anti-rubella vaccination rates were widely unsatisfactory. Being mEPP and reporting allergy were significantly associated to higher rates of VH. Tailored strategies targeting on vaccine safety are needed for retention of these women in immunisation programmes.

Childhood Traumatic Experiences and Coping Strategies: Correlations With Quality of Life

Introduction

Individuals with a history of childhood traumatic experiences may exert maladaptive coping strategies and impaired adult quality of life.

Objectives

The present study explored the association between childhood traumatic experiences, coping strategies, and quality of life.

Aims

We aimed to evaluate whether childhood traumatic experiences or specific coping strategies may significantly predict quality of life.

Methods

This is a cross-sectional study including 276 patients (19.9% men, 81.1% women; mean age: 48.1 years, SD: 16.9), of which most with major affective disorders, who were recruited at the psychiatric unit of the university of Genoa (Italy). All participants were assessed using the Childhood Trauma Questionnaire (CTQ), Coping Orientation to Problems Experienced (Cope), and Short Form 12 Health Survey version 2 (SF-12).

Results

Subjects with a history of emotional abuse were more likely to have an earlier age of onset of their psychiatric conditions, an earlier age of their first treatment/hospitalization, higher recurrent episodes and days of hospitalization, longer illness duration and non-psychiatric treatments at intake when compared with those who did not present any history of abuse. Based on regression analyses, only positive reinterpretation and growth, focus on and venting of emotions, and substance abuse, but not childhood traumatic experiences, resulted positive predictors of physical quality of life. Moreover, focus on and venting of emotions was able to predict mental quality of life.

Conclusions

While traumatic experiences did not predict quality of life, specific coping strategies were significant predictors of quality of life. Further studies are requested to test these preliminary results.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

HBsAg kinetics in chronic hepatitis D during interferon therapy: on-treatment prediction of response

BACKGROUND

Therapy of chronic hepatitis D with Interferon is successful when testing for HDV-RNA turns negative. This end-point is disputed.

AIM

To assess the role of serum hepatitis B surface antigen (HBsAg) in the clearance of HDV-RNA in pegylated interferon (Peg-IFN)-treated chronic hepatitis D (CHD).

METHODS

Sixty-two patients with CHD, treated with Peg-IFN, were considered. The patients belonged to three groups: 14 patients cleared the HBsAg and HDV-RNA (responders, R), 12 cleared the HDV-RNA remaining positive for HBsAg (partial responders, PR) and 36 cleared neither the HBsAg nor the HDV-RNA (nonresponders, NR).

RESULTS

In responders, at baseline the median value (mv) of HBsAg and HDV-RNA was 1187 and 188 663 IU/mL. By month 6 of therapy, HBsAg declined to less than 1000 IU/mL and HDV-RNA was undetectable in 12 patients. In NR, the pre-therapy median value of HBsAg and HDV viremia was 6577 and 676 319 IU/mL. There was no significant reduction of antigen at month 6; after a decline, HDV-RNA rebounded to baseline levels. In PR, the median value of baseline HBsAg was 7031 IU/mL; it declined at month 6 in the majority. HDV-RNA progressively declined from an initial median value of 171 405 IU/mL. HBsAg <1000 IU/mL at month 6 discriminated responders and PR from NR (P < 0.001). By ROC curve, the threshold of 0.105 log reduction of HBsAg associated with 1.610 log reduction of HDV-RNA from baseline to month 6 predicted the clearance of this marker.

CONCLUSIONS

A reduction of serum HBsAg is mandatory for the definitive clearance of the HDV-RNA. Quantitative HBsAg may predict the long-term response to Peg-IFN therapy and provide a guide to prolong or stop treatment.

Prediction of occult hepatitis B virus infection in liver transplant donors through hepatitis B virus blood markers

BACKGROUND

Occult hepatitis B virus infection is defined as detectable HBV-DNA in liver of HBsAg-negative individuals, with or without detectable serum HBV-DNA. In deceased liver donors, results of tissue analysis cannot be obtained prior to allocation for liver transplantation.

AIMS

we investigated prevalence and predictability of occult hepatitis B using blood markers of viral exposure/infection in deceased liver donors.

METHODS

In 50 consecutive HBsAg-negative/anti-HBc-positive and 20 age-matched HBsAg-negative/anti-HBc-negative donors, a nested-PCR assay was employed in liver biopsies for diagnosis of occult hepatitis B according to Taormina criteria. All donors were characterized for plasma HBV-DNA and serum anti-HBs/anti-HBe.

RESULTS

In liver tissue, occult hepatitis B was present in 30/50 anti-HBc-positive (60%) and in 0/20 anti-HBc-negative donors (p<0.0001). All anti-HBc-positive donors with detectable HBV-DNA in plasma (n=5) or anti-HBs>1,000 mIU/mL (n=5) eventually showed occult infection, i.e, 10/30 occult hepatitis B-positive donors which could have been identified prior to transplantation. In the remaining 40 anti-HBc-positive donors, probability of occult infection was 62% for anti-HBe-positive and/or anti-HBs ≥ 58 mIU/mL; 29% for anti-HBe-negative and anti-HBs<58 mIU/mL.

CONCLUSIONS

In deceased donors, combining anti-HBc with other blood markers of hepatitis B exposure/infection allows to predict occult hepatitis B with certainty and speed in one third of cases. These findings might help refine the allocation of livers from anti-HBc-positive donors.

Valganciclovir as pre-emptive therapy for cytomegalovirus infection post-allogenic stem cell transplantation: implications for the emergence of drug-resistant cytomegalovirus

OBJECTIVES

Valganciclovir is a well established drug for the management of cytomegalovirus (CMV) infection in haematopoietic stem cell transplantation (HSCT). Data concerning its safety regarding the development of drug resistance are required. The aim of the present study was to retrospectively investigate CMV drug resistance in a group of HSCT patients experiencing relapses of CMV infection after a first-line pre-emptive antiviral therapy.

METHODS

Thirteen adult HSCT patients out of 26 with asymptomatic CMV infection, experiencing relapsing infections 45-155 days after either intravenous (iv) ganciclovir (2 patients) or valganciclovir (11 patients), were studied. Genotypic assays for mutations in the viral phosphotransferase (UL97) and DNA-polymerase (UL54) genes were directly applied on patient specimens. Baseline CMV sequences were compared with those at the time of relapses to identify drug-resistant strains.

RESULTS

UL97 mutations A594V and M460V known to confer drug resistance developed in one relapsing patient who received iv ganciclovir as first-line therapy, corresponding to a rate of 7.7% of relapses due to drug-resistant strains and an overall 3.8% rate of infections due to CMV drug-resistant strains. UL54 drug resistance mutations were absent. No evidence of drug resistance was found in patients on valganciclovir either as first-line therapy or as treatment for relapses.

CONCLUSIONS

The safety profile of valganciclovir as anti-CMV pre-emptive therapy was confirmed, as well as that monitoring CMV drug resistance with genotypic tests on sequential isolates over the time-course of therapy offers guidance to tailor antiviral treatment in a clinically relevant time frame.

Clinical evaluation of the COBAS Ampliprep/COBAS TaqMan for HCV RNA quantitation in comparison with the branched-DNA assay

Diagnosis and monitoring of HCV infection relies on sensitive and accurate HCV RNA detection and quantitation. The performance of the COBAS AmpliPrep/COBAS TaqMan 48 (CAP/CTM) (Roche, Branchburg, NJ), a fully automated, real-time PCR HCV RNA quantitative test was assessed and compared with the branched-DNA (bDNA) assay. Clinical evaluation on 576 specimens obtained from patients with chronic hepatitis C showed a good correlation (r = 0.893) between the two test, but the CAP/CTM scored higher HCV RNA titers than the bDNA across all viral genotypes. The mean bDNA versus CAP/CTM log10 IU/ml differences were -0.49, -0.4, -0.54, -0.26 for genotype 1a, 1b, 2a/2c, 3a, and 4, respectively. These differences reached statistical significance for genotypes 1b, 2a/c, and 3a. The ability of the CAP/CTM to monitor patients undergoing antiviral therapy and correctly identify the weeks 4 and 12 rapid and early virological responses was confirmed. The broader dynamic range of the CAP/CTM compared with the bDNA allowed for a better definition of viral kinetics. In conclusion, the CAP/CTM appears as a reliable and user-friendly assay to monitor HCV viremia during treatment of patients with chronic hepatitis. Its high sensitivity and wide dynamic range may help a better definition of viral load changes during antiviral therapy.

Comparison of the Cobas Ampliprep/Cobas TaqMan HBV Test versus the Cobas Amplicor HBV monitor for HBV-DNA detection and quantification during antiviral therapy

Performances of the new automatic system COBAS AmpliPrep/COBAS TaqMan 48 (CAP/CTM) (Roche, Branchburg, NJ) for HBV DNA extraction and real-time PCR quantification were assessed and compared with the endpoint PCR COBAS AMPLICOR HBV Monitor (CAHBM, Roche). Analytical evaluation with proficiency panels from UK National External Quality Assessment Scheme (UK NEQAS) over a 1-year period of distribution showed that CAP/CTM correctly measured HBV DNA levels with a close correlation between expected and observed values (r=0.995). Clinical evaluation as tested with samples from 11 HBsAg-positive patients undergoing antiviral therapy (71 serial specimens of plasma), demonstrated excellent correlation with CAHBM (r=0.958, mean difference in quantitation: 0.14 log, IU/ml), but CAP/CTM detected longer period of residual viremia. HBV DNA reduction was much higher in the combination schedule (Lamivudine+Adefovir), than in Adefovir monotherapy (5.1 vs. 3.5 logs). In conclusion, CAP/CTM allows for an accurate and standardized quantification of HBV DNA in high through-put laboratories. Due to it high sensitivity, it may further improve the detection of emerging drug resistance strains and the assessment of antiviral therapy.

COBAS AmpliPrep-COBAS TaqMan hepatitis B virus (HBV) test: a novel automated real-time PCR assay for quantification of HBV DNA in plasma

Success in antiviral therapy for chronic hepatitis B is supported by highly sensitive PCR-based assays for hepatitis B virus (HBV) DNA. Nucleic acid extraction from biologic specimens is technically demanding, and reliable PCR results depend on it. The performances of the fully automatic system COBAS AmpliPrep-COBAS TaqMan 48 (CAP-CTM; Roche, Branchburg, NJ) for HBV DNA extraction and real-time PCR quantification were assessed and compared to the endpoint PCR COBAS AMPLICOR HBV monitor (CAHBM; Roche). Analytical evaluation with a proficiency panel showed that CAP-CTM quantitated HBV DNA levels in one single run over a wide dynamic range (7 logs) with a close correlation between expected and observed values (r = 0.976, interassay variability below 5%). Clinical evaluation, as tested with samples from 92 HBsAg-positive patients, demonstrated excellent correlation with CAHBM (r = 0.966, mean difference in quantitation = 0.36 log(10) IU/ml). CAP-CTM detected 10% more viremic patients and longer periods of residual viremia in those on therapy. In lamivudine (LAM)-resistant patients, the reduction of HBV DNA after 12 months of Adefovir (ADF) was higher in the combination (LAM+ADF) schedule than in ADF monotherapy (5.1 logs versus 3.5 logs), suggesting a benefit in continuing LAM. CAP-CTM detected HBV DNA in liver biopsy samples from 15% of HBsAg-negative, anti-HBcAg-positive graft donors with no HBV DNA in plasma. The amount of intrahepatic HBV DNA was significantly lower in occult HBV infection than in overt disease. CAP-CTM can improve the management of HBV infection and the assessment of antiviral therapy and drug resistance, supporting further insights in the emerging area of occult HBV infection.

Quantitation of cytomegalovirus DNA by real-time polymerase chain reaction in peripheral blood specimens of patients with solid organ transplants: Comparison with end-point PCR and pp65 antigen test

The polymerase chain reaction (PCR) for cytomegalovirus (CMV) DNA quantitation provides sensitive and specific data for detecting CMV as well as monitoring the infection and determining the appropriate antiviral strategy. A recently introduced real-time PCR assay for CMV DNA quantitation was applied on 158 peripheral blood leukocytes (PBLs) from 32 liver-transplanted patients with CMV asymptomatic infection and correlated with a commercial quantitative end-point PCR (COBAS AMPLICOR CMV Monitor) and CMV pp65 antigenemia. A good correlation was found between real-time PCR and pp65 antigen test (r2 = 0.691) and the two PCR assays (r2 = 0.761). Real-time PCR data were higher in pre-emptive treated patients (>20 pp65 + positive cells, median CMV DNA value: 3.8 log(10) copies/500,000 PBLs) than in not-treated ones (2.9 logs). According to pp65 levels of 0, 1-10, 11-20, 21-50, 51-100, and >100 positive cells/200,000 PBLs, median CMV DNA by real-time PCR was 2.6, 3.0, 3.6, 4.0, 4.2, and 4.8 logs, respectively, (CMV DNA levels by COBAS AMPLICOR: 2.8, 2.9, 3.8, 3.7, 3.9, and 4.0 logs). For samples with >20 pp65 + cells, real-time PCR gave significantly higher values than in groups with <20 pp65 + cells, whereas the COBAS AMPLICOR results showed a slower progression rate. Dilutions of CMV AD169 strain were used to probe real-time PCR reproducibility (between and intra-assay variability <2%) and sensitivity (100% detection rate at 10 copies/reaction, 28.5% with end-point PCR). In conclusion, real-time PCR significantly improves the study of CMV DNA dynamics due to a more reliable quantitation of CMV DNA for moderate and high DNA level compared to end-point PCR with better sensitivity and specificity. Real-time PCR provides more precise information for evaluating infection progress and assessing antiviral response, simplifying and accelerating the process of producing a reliable quantitation of CMV DNA for clinical purposes.

Quantitation of cytomegalovirus DNA by the polymerase chain reaction as a predictor of disease in solid organ transplantation

Cytomegalovirus (CMV) infection is an important cause of morbidity in solid organ recipients. Early markers to identify the progress of the infection and patients at high risk are required in order to apply a strategy of pre-emptive therapy. The efficacy of pre-emptive therapy relies on accurate laboratory tests to monitor CMV infection. The evaluation of CMV DNA kinetics by the polymerase chain reaction (PCR) is widely used for the management of CMV infection but markers predicting the progression of the infection and standardization of the technique are essential for the clinical interpretation of PCR results. A commercially available PCR system, the COBAS AMPLICOR Monitor (Roche Diagnostics, Brachburg, NJ), was used for the quantitation of CMV DNA in weekly blood samples (n = 504) from 47 solid organ recipients in the first 6 months after transplantation. PCR results were evaluated according to the development of clinical disease in order to find a DNA threshold and time points predicting the progression of CMV infection. Week 4 from transplantation was the earliest time point to note a significant difference between those patients who eventually developed CMV disease (n = 30) and those who remained asymptomatically infected (n = 17). At week 4, viral loads were significantly higher in patients who developed CMV disease than in asymptomatic infections (median value: 4 log(10)/10(6) leukocytes vs. 2.8, P < 0.0001). At week 4, a DNA level >/=4 log(10)/10(6) leukocytes was associated with a 45.37 odds ratio for CMV disease. Any increase >/=1 log from the first DNA detection to week 4 correlated with the clinical progression of CMV infection (odds ratio 1.74). In those patients who were treated with anti-CMV therapy, a >97% reduction of the baseline viral load was associated with a complete therapeutic success. In conclusion, CMV infection is a highly dynamic process and the quantitation of CMV DNA by PCR is a powerful marker to control successfully the infection, but a strict follow-up of the recipient and standardized PCR tests are mandatory for the best management of the infection.

Intrinsic penicillin resistance in enterococci

Penicillin resistance development in enterococci has been associated with overproduction of a low-affinity penicillin-binding protein (PBP) that is a normal component of the PBP pattern of these bacteria and is apparently able to substitute the functions of the other PBPs. In resistant mutants of Enterococcus hirae ATCC 9790 the low-affinity PBP (PBP5) overproduction was associated with a deletion in a genetic element, located 1 kb upstream of the pbp5 gene, which negatively controlled PBP5 synthesis. Hypersusceptibility to penicillin was associated with a point mutation in the pbp5 gene, which causes premature termination of translation. Structural homologies between low-affinity PBPs of the different enterococcal species have been suggested by cross-reactivity of antibodies raised against E. hirae PBP5 with PBP5 of Enterococcus faecium and Enterococcus faecalis. Acquisition of a high-level ampicillin resistance in E. faecium was associated with overproduction of PBP5, which, compared with PBP5 of moderately resistant strains, appeared to be modified in its penicillin-binding capability. The modified phenotype of PBP5 was found to be associated to some amino acid substitutions in the region between the SDN and KTG motifs. In particular, the substitution converting a polar residue (T) in a nonpolar one (A or I) could play an important role in remodeling the penicillin-binding domain and determining the decrease in penicillin affinity.

Quantitation of human cytomegalovirus DNA in peripheral blood leukocytes of heart transplant recipients: relationship with pp65 antigenemia and with antiviral therapy

OBJECTIVE: To retrospectively determine DNA levels in blood polymorphonuclear leukocytes (PMNLs) of 21 heart transplant patients who suffered from HCMV infection and who were monitored by the antigenemia assay (pp65 test) during follow-up, by use of a quantitative competitive polymerase chain reaction (PCR) assay for human cytomegalovirus (HCMV) DNA. METHODS: Quantitation of HCMV DNA by PCR was expressed as genome equivalents (GE) per 200 000 PMNLs. RESULTS: Ten patients experienced symptomatic HCMV infection (five primary infections and five reactivations) with mild symptoms and received ganciclovir treatment, whereas 11 asymptomatic HCMV infections were not treated. Therapy was discontinued when a 90% reduction of the pretreatment antigenic load was achieved in a symptomless patient. The mean HCMV DNA and antigenic loads were significantly higher in symptomatic than in asymptomatic patients: 4.6 x 105 plus minus 4.7 x 105 GE and 1.1 x 104 GE (p<0.0001) and 390 plus minus 350 versus 25 plus minus 12 pp65-positive PMNLs (p<0.0001), and in primary than in secondary infections (583 plus minus 403 pp65-positive PMNLs versus 85 plus minus 111, p=0.002 and 5.2 x 105 plus minus 5.2 x 105 GE instead of 1.5 x 105 plus minus 3.2 x 105 GE, p=0.02). A single course of 14--21 days of ganciclovir caused a marked decrease of HCMV DNA and antigenemia in eight of 10 patients in whom a 90% reduction of the antigenic load correlated with a 98% DNA reduction of the pretreatment levels. In two primary infections, a 90% antigenic reduction was achieved by 21 days of ganciclovir treatment, but those data only correlated with a DNA load reduction of 28% and 60% of the pretreatment levels. Fifteen and 12 days later, respectively, the two patients relapsed and underwent a second ganciclovir course, at the end of which a 90% reduction of the antigenic load correlated with a >98% DNA drop. GCV was discontinued and the patients recovered completely. In those two patients we retrospectively found persistent high DNA levels before the second ganciclovir course, whereas the antigenic load slowly increased after an apparent reduction. CONCLUSIONS: Our data suggest that: (1) DNA levels have the same trend as the pp65 antigen test---they are significantly higher in symptomatic and in primary HCMV-infected patients than in asymptomatic patients and those with secondary infection; (2) a 90% antigenic load reduction from the pre-treatment level may be a less reliable predictor of the efficacy of anti-HCMV therapy than DNA load, at least in primary infection, in which a much higher viral load and much more severe disease are present; and (3) a DNA load reduction of >98% of the pretreatment value is required for therapeutic success.

Sequential versus concomitant administration of ribavirin and interferon alfa-n3 in patients with chronic hepatitis C not responding to interferon alone: results of a randomized, controlled trial

We conducted a three-arm, randomized trial in 96 patients with chronic hepatitis C who did not respond to interferon alfa to compare treatments. Group 1 (33 patients) received ribavirin alone (1,000 mg/daily for 6 months) followed by interferon alfa n-3 alone (3 MU thrice weekly for 6 months); group 2 (33 patients) received ribavirin plus interferon alfa n-3 for 6 months at the above doses; and group 3 (30 patients) received interferon alfa n-3 alone (3 MU thrice weekly for 6 months). At the end of treatment, 3 patients (10%) in group 1, 13 (41%) in group 2, and 5 (17%) in group 3 had normal alanine transaminase (ALT) levels (group 2 vs. groups 1 and 3, P = .008). After 6 months of follow-up, only 4 patients (12.5%) in group 2 still had normal ALT values (P = .03). At the end of therapy, hepatitis C virus (HCV) RNA was no longer detectable by polymerase chain reaction in 4 (13%), 9 (27%), and 2 (7%) patients, respectively, in groups 1, 2, and 3 (P = NS). Six months posttherapy, only 5 (15%) patients in group 2 were still HCV RNA negative (P = .02). At the time of follow-up liver biopsy, performed 6 months after the end of treatment, a significant improvement of the necroinflammatory scores was observed among group 2 patients (P = .01) but not in the other two groups. Side effects reflected the profile of each drug as monotherapy; mild hemolytic anemia was the most frequent side effect caused by ribavirin. In conclusion, concomitant administration of ribavirin and interferon alfa n-3 was significantly superior to the sequential schedule or interferon alfa n-3 monotherapy in inducing a sustained response in patients with chronic hepatitis C who had not responded to interferon alone. However, combination therapy at the dose and duration adopted in this study is capable of modifying the natural course of the disease in only a minority of these patients.

Modification of penicillin-binding protein 5 associated with high-level ampicillin resistance in Enterococcus faecium

High-level ampicillin resistance in Enterococcus faecium has been shown to be associated with the synthesis of a modified penicillin-binding protein 5 (PBP 5) which had apparently lost its penicillin-binding capability (R. Fontana, M. Aldegheri, M. Ligozzi, H. Lopez, A. Sucari, and G. Satta. Antimicrob. Agents Chemother. 38:1980-1983, 1994). The pbp5 gene of the highly resistant strain E. faecium 9439 was cloned and sequenced. The deduced amino acid sequence showed 77 and 54% homologies with the PBPs 5 of Enterococcus hirae and Enterococcus faecalis, respectively. A gene fragment coding for the C-terminal part of PBP 5 containing the penicillin-binding domain was also cloned from several E. faecium strains with different levels of ampicillin resistance. Sequence comparison revealed a few point mutations, some of which resulted in amino acid substitutions between SDN and KTG motifs in PBPs 5 of highly resistant strains. One of these converted a polar residue (the T residue at position 562 or 574) of PBP 5 produced by susceptible and moderately resistant strains into a nonpolar one (A or I). This alteration could be responsible for the altered phenotype of PBP 5 in highly resistant strains.

Identification of a genetic element (psr) which negatively controls expression of Enterococcus hirae penicillin-binding protein 5

Enterococcus hirae ATCC 9790 produces a penicillin-binding protein (PBP5) of low penicillin affinity which under certain conditions can take over the functions of all the other PBPs. The 7.1-kb EcoRI fragment containing the pbp5 gene of this strain and of two mutants, of which one (E. hirae R40) overproduces PBP5 and the other (E. hirae Rev14) does not produce PBP5, was cloned in pUC18 and sequenced. In the 7.1-kb EcoRI fragment cloned from strain ATCC 9790, an open reading frame (psr) potentially encoding a 19-kDa protein was identified 1 kb upstream of the pbp5 gene. An 87-bp deletion in this element was found in the 7.1-kb EcoRI fragment cloned from strains R40 and Rev14. In addition, several base substitutions were found in the pbp5 genes of strains R40 and Rev14. One of these converted the 42nd codon, TCA, to the stop codon, TAA, in the pbp5 gene of Rev14. Escherichia coli strains were transformed with plasmids carrying the 7.1-kb EcoRI insert or a 2.6-kb HincII insert containing only the pbp5 gene of the three strains. Immunoblotting analysis of proteins expressed by these transformants showed that the 87-bp deletion in psr was associated with the PBP5 overproducer phenotype of strain R40 and the conversion of the TCA codon to the stop codon was associated with the PBP5 nonproducer phenotype of strain Rev14. None of the other nucleotide substitutions had any apparent effect on the level of PBP5 synthesized.

Analysis of bacteriolytic activity patterns, a novel approach to the taxonomy of enterococci

The bacteriolytic activities of different group D streptococcal species on various media and substrates were studied. Our results showed that all of the enterococcal species which we tested had bacteriolytic activity on at least one of the media used, while the group D nonenterococcal species had no such activity. In addition, using culture media containing different additives and different pH values, we defined seven major groups of bacteriolytic activity (lyogroups), each of which overlapped with one species (four lyogroups), two species (two lyogroups), or four species (one lyogroup). The detection of enterococcal lyogroups proved to be as reliable for species identification as the conventional methods presently in use.