Automated quantification of Epstein-Barr virus in whole blood for post-transplant lymphoproliferative disorders monitoring.

BACKGROUND: Standardized and sensitive assays for Epstein Barr Virus (EBV) are needed to define universal cutoff for treatment initiation in allogeneic hematopoietic stem cells transplant recipients. In a context of accreditation and the availability of EBV international standard, we evaluated the Abbott RealTime EBV (RT) assay for EBV quantification in whole blood. METHODS: The RT assay was compared on 282 prospective clinical samples with the Artus EBV PCR Kit V1 assay (V1) and we analyzed the kinetics of EBV load in 11 patients receiving rituximab treatment. RESULTS: The estimated limit of detection was 88 IU/mL. The assay was linear (r2 = 0.9974) in the range of all samples tested (100 to 1,000,000 IU/mL). Intra-assay coefficients of variation (CV) ranged between 0.35 and 1.35%, and inter-assay CV between 3.40 and 4.5%. On samples above the limit of quantification, the two assays were strongly correlated. EBV RT values were on average 0.30 log10 IU/mL lower than those measured with the V1 assay. In patients treated with rituximab, the RT assay remained positive in 5 patients at the time it dropped below undetectable levels with the V1 assay. CONCLUSIONS: In conclusion, the RT assay is a reliable assay for EBV load in whole blood. Its sensitivity will enable to estimate the kinetics of EBV load and the impact of treatments to control EBV reactivations.

Evaluation of a New Device for Simplifying and Standardizing Stool Sample Preparation for Viral Molecular Testing with Limited Hands-On Time.

Sensitive molecular assays have greatly improved the diagnosis of viral gastroenteritis. However, the proper preparation of stool samples for clinical testing remains an issue. bioMérieux has developed a stool preprocessing device (SPD) that includes a spoon for calibrated sampling and a vial containing buffer, glass beads, and two filters. The resulting stool filtrate is used for nucleic acid extraction. The purpose of this study was to evaluate the performance of the SPD for the quantification of human adenovirus (HAdV) DNA in stool samples collected from hematopoietic stem cell transplant (HSCT) recipients. HAdV DNA was quantified with the Adenovirus R-gene kit. The suitability of the device to reproducibly quantify HAdV DNA in stools using different extraction platforms (easyMAG and QIAsymphony) was determined using archived HAdV-positive stool samples. Coefficients of variation of HAdV DNA quantifications ranged from 1.79% to 1.83%, and no difference in quantification was observed between the two extraction systems. The HAdV DNA limit of quantification using the SPD was 3.75 log10copies/g of stool. HAdV DNA quantification using the SPD was then compared to that of the routine preprocessing technique on 75 fresh stool samples collected prospectively from pediatric HSCT recipients at risk for HAdV infections. Thirty-eight samples were HAdV DNA positive with both the SPD and routine preprocessing methods. HAdV DNA loads were on average 1.14-log10copies/g of stool higher with the SPD (P< 0.0001) than with routine methods. This new device enabled a standardized preparation of stool samples in <5 min and a reproducible and sensitive quantification of HAdV DNA. The use of the SPD for the detection of other gastrointestinal infections warrants further evaluation.

Favorable impact of natural killer cell reconstitution on chronic graft-versus-host disease and cytomegalovirus reactivation after allogeneic hematopoietic stem cell transplantation.

Natural killer cells are the first lymphocyte subset to reconstitute, and play a major role in early immunity after allogeneic hematopoietic stem cell transplantation. Cells expressing the activating receptor NKG2C seem crucial in the resolution of cytomegalovirus episodes, even in the absence of T cells. We prospectively investigated natural killer-cell reconstitution in a cohort of 439 adult recipients who underwent non-T-cell-depleted allogeneic hematopoietic stem cell transplantation between 2005 and 2012. Freshly collected blood samples were analyzed 3, 6, 12 and 24 months after transplantation. Data were studied with respect to conditioning regimen, source of stem cells, underlying disease, occurrence of graft-versus-host disease, and profiles of cytomegalovirus reactivation. In multivariate analysis we found that the absolute numbers of CD56(bright) natural killer cells at month 3 were significantly higher after myeloablative conditioning than after reduced intensity conditioning. Acute graft-versus-host disease impaired reconstitution of total and CD56(dim) natural killer cells at month 3. In contrast, high natural killer cell count at month 3 was associated with a lower incidence of chronic graft-versus-host disease, independently of a previous episode of acute graft-versus-host disease and stem cell source. NKG2C(+)CD56(dim) and total natural killer cell counts at month 3 were lower in patients with reactivation of cytomegalovirus between month 0 and month 3, but expanded greatly afterwards. These cells were also less numerous in patients who experienced later cytomegalovirus reactivation between month 3 and month 6. Our results advocate a direct role of NKG2C-expressing natural killer cells in the early control of cytomegalovirus reactivation after allogeneic hematopoietic stem cell transplantation.

Broad-range PCR-electrospray ionization mass spectrometry for detection and typing of adenovirus and other opportunistic viruses in stem cell transplant patients.

Hematopoietic stem cell transplant patients are highly susceptible to viral infections. Follow-up after transplantation includes weekly screening using single, virus-specific real-time PCR tests, mainly for viruses in the families Herpesviridae and Adenoviridae that contribute to a high morbidity, especially in pediatric populations. The Abbott PLEX-ID platform combines broad-range PCR with electrospray ionization mass spectrometry to enable the simultaneous detection of multiple pathogens in a single assay. The Viral IC Spectrum assay detects human adenoviruses, viruses from the family Herpesviridae (herpes simplex virus 1 [HSV-1], HSV-2, cytomegalovirus [CMV], Epstein-Barr virus [EBV], varicella-zoster virus [VZV], and human herpesvirus 8 [HHV-8]), human enterovirus, polyomaviruses (BK and JC), and parvovirus B19. We evaluated the performance of the Viral IC Spectrum assay with samples from 16 adult and 36 pediatric stem cell transplant patients. The sensitivity of the Viral IC Spectrum assay compared to real-time PCR quantification using the adenovirus Rgene kit for the detection of adenovirus was 96.7% from plasma samples (n = 92) and 78% from stool samples (n = 100). No adenovirus was detected in samples from noninfected patients (n = 30). PLEX-ID species identification was perfectly concordant with species-specific real-time PCR assays. In plasma and stool samples, the level of amplified products measured by PLEX-ID and the quantity in copies/ml (r = 0.82 and 0.78, respectively) were correlated up to 6 log10 copies/ml. In 67.4% of adenovirus-positive plasma samples, at least one other viral infection was detected; these included BK virus (n = 41), CMV (n = 30), EBV (n = 26), JC virus (n = 9), and HSV-1 (n = 6). The results of this study suggest that the Viral IC Spectrum assay performed on the PLEX-ID platform is reliable for adenovirus infection diagnosis in immunocompromised patients.

Fully automated quantification of cytomegalovirus (CMV) in whole blood with the new sensitive Abbott RealTime CMV assay in the era of the CMV international standard.

Fully standardized reproducible and sensitive quantification assays for cytomegalovirus (CMV) are needed to better define thresholds for antiviral therapy initiation and interruption. We evaluated the newly released Abbott RealTime CMV assay for CMV quantification in whole blood (WB) that includes automated extraction and amplification (m2000 RealTime system). Sensitivity, accuracy, linearity, and intra- and interassay variability were validated in a WB matrix using Quality Control for Molecular Diagnostics (QCMD) panels and the WHO international standard (IS). The intra- and interassay coefficients of variation were 1.37% and 2.09% at 5 log10 copies/ml and 2.41% and 3.80% at 3 log10 copies/ml, respectively. According to expected values for the QCMD and Abbott RealTime CMV methods, the lower limits of quantification were 104 and <50 copies/ml, respectively. The conversion factor between international units and copies (2.18), determined from serial dilutions of the WHO IS in WB, was significantly different from the factor provided by the manufacturer (1.56) (P = 0.001). Results from 302 clinical samples were compared with those from the Qiagen artus CMV assay on the same m2000 RealTime system. The two assays provided highly concordant results (concordance correlation coefficient, 0.92), but the Abbott RealTime CMV assay detected and quantified, respectively, 20.6% and 47.8% more samples than the Qiagen/artus CMV assay. The sensitivity and reproducibility of the results, along with the automation, fulfilled the quality requirements for implementation of the Abbott RealTime CMV assay in clinical settings. Our results highlight the need for careful validation of conversion factors provided by the manufacturers for the WHO IS in WB to allow future comparison of results obtained with different assays.

The complex relationship between human herpesvirus 6 and acute graft-versus-host disease.

The most frequent manifestation of human herpesvirus 6 (HHV-6) reactivation after allogeneic hematopoietic stem cell transplantation (HSCT) is febrile rash, raising the question of its relationship with graft-versus-host disease (GVHD). In this retrospective analysis of 365 patients who underwent allogeneic HSCT, HHV-6 reactivation was significantly associated with cord blood transplantation (hazard ratio [HR], 3.20; P < .0001) and the use of unrelated donors (HR, 2.02; P = .008). On multivariate analysis, previous GVHD was a predictive factor for HHV-6 reactivation (HR, 1.80; P = .01), and previous HHV-6 reactivation was a predictive factor for acute GVHD (HR, 1.66; P = .03). Nineteen patients with no pathological evidence of GVHD later developed severe clinical GVHD (grade III-IV), suggesting the role of HHV-6 as a trigger for severe GVHD. Furthermore, 17 patients without histopathological GVHD demonstrated a significant lymphoid infiltrate suggesting "pure" HHV-6-related manifestations, and these patients could have been spared steroid therapy.

Confirmation of the low clinical effect of human herpesvirus-6 and -7 infections after renal transplantation.

Human herpesvirus-6 and -7 (HHV-6 and HHV-7) may lead to pathological manifestations in renal transplant recipients. The aim of this study was to investigate beta-herpesvirus infections in 50 adult kidney transplant recipients after transplantation to examine the effect, interactions, and pathogenic consequences of infection and the effect of immunosuppressive regimens and Human cytomegalovirus (HCMV) prophylaxis with VACV. Beta-herpesviruses loads in the blood of 50 adult kidney transplant recipients over a 6-month period after transplantation and 198 blood donors were determined using polymerase chain reaction. The rate of HHV-6 detection in peripheral mononuclear cells (PBMCs) was higher in patients with end-stage renal disease and during the post-transplantation follow-up than in healthy subjects (33% and 68% vs. 12%, respectively). The detection rate of HHV-7 in PBMCs was similar between patients, both before grafting and during the follow-up for transplant recipients (69% and 88%, respectively), and healthy subjects (78%), and correlated with the number of lymphocytes. HCMV in plasma was detected only in patients during the post-transplant period (24%). VACV prophylaxis had no negative effect on the replication of HHV-6 or HHV-7, and univariate analyses demonstrated associations between HHV-6 infection and acute graft rejection [Odds ratio (OR) = 2.94, 95% confidence interval (CI), 1.05-8.2, P = 0.04], and between HHV-7 infection and cholestasis [OR = 2.61 (95% CI, 1.08-6.3), P = 0.03]. Immunosuppressive regimens had no effect on beta-herpesviruses infections. This study revealed the differing behavior of HCMV, HHV-6, and HHV-7 in kidney transplant recipients, and confirmed the association of HHV-6 with graft rejection.

MICA-129 genotype, soluble MICA, and anti-MICA antibodies as biomarkers of chronic graft-versus-host disease.

The MHC class I-related chain A (MICA) molecules exist as membrane-bound and soluble isoforms and are encoded by a polymorphic gene. Their genetic and phenotype characteristics have been studied in various pathologic settings but not in the context of hematopoietic stem cell transplantation (HSCT). Here, we evaluated whether MICA-related features namely MICA-129 gene polymorphism, serum levels of soluble MICA (sMICA) and anti-MICA antibodies (MICA Abs) before and after HSCT could influence the incidence of chronic graft-versus-host disease (cGVHD) and relapse of their disease in 211 HLA-identical sibling pairs and in a subset of 116 recipients, respectively. Although the MICA-129 val/val genotype and elevated sMICA serum levels after HSCT are independently associated with the incidence of cGVHD (P = .002 and .001) regardless of history of acute GVHD, the presence of MICA Abs before transplantation confers protection against cGVHD (P = .04). There is an inverse relationship between MICA Abs and sMICA, suggesting an antibody-based neutralization of deleterious effects of sMICA. Similarly, these genetic and phenotype characteristics of MICA influence the incidence of relapse. Altogether, these data suggest that the studied MICA genotype and phenotype specificities could be used as relevant biomarkers for cGVHD monitoring.

Etiology of genital ulcer disease. A prospective study of 278 cases seen in an STD clinic in Paris.

OBJECTIVES: The goal of this study was to identify the causes and factors associated with genital ulcer disease (GUD) among patients attending a sexually transmitted disease (STD) clinic in Paris. METHODS: This study was a prospective investigation of GUD cases. Data were collected from 1995 to 2005. In each case, a Dark Field Examination (DFE), Gram stain, inoculation onto Thayer Martin agar, Columbia agar and chocolate agar with 1% isovitalex and 20% fetal calf serum, PCR Chlamydia trachomatis (Amplicor Roche), culture for herpes simplex virus (HSV) on MRC 5 cells and PCR HSV (Argene Biosoft) were obtained from the ulceration. First Catch Urine (FCU) PCR for Chlamydia trachomatis and syphilis, HIV, HSV, and HBV serologies were also performed. RESULTS: A total 278 cases of GUD were investigated, 244 (88%) in men and 34 (12%) in women. Primary syphilis accounted for 98 cases (35%), genital herpes for 74 (27%), chancroid for 8 (3%), other infections for 12 (5%). In 91 (32%) patients, no identifiable microorganism was documented. Primary syphilis was more prevalent in MSMs (P < 0.0001), while genital herpes and chancroid were significantly associated with heterosexuality (both P < 0.0001). A high level of HIV infection (27%) was found, particularly in patients with primary syphilis (33%). In the univariate analysis, no statistical difference was found between syphilis and herpes according to clinical presentation, pain being the only item slightly more frequent in herpes (P = 0.06). In the multivariable model syphilis was associated with being MSM (OR: 51.3 [95% CI: 14.7-178.7], P < 0.001) and with an ulceration diameter >10 mm (OR: 9.2 [95% CI: 2.9-30.7], P < 0.001). Genital herpes was associated with HIV infection in the subgroup of MSWs (OR: 24.4 [2.4-247.7], P = 0.007). We did not find significant differences in the clinical presentation of the ulcers according to HIV status. CONCLUSION: The profound changes of the epidemiology of GUD during the decade, due to disappearance of chancroid and reemergence of infectious syphilis have led to a new distribution of pathogens, genital herpes, primary syphilis and GUD from unknown origin, accounting each for one third of cases. No clinical characteristic is predictive of the etiology, underlining the importance of performing a thorough microbiologic evaluation. Close association with HIV is still a major public health problem.

An unusual CD56(bright) CD16(low) NK cell subset dominates the early posttransplant period following HLA-matched hematopoietic stem cell transplantation.

The expansion of the cytokine-producing CD56(bright) NK cell subset is a main feature of lymphocyte reconstitution after allogeneic hematopoietic stem cell transplantation (HSCT). We investigated phenotypes and functions of CD56(bright) and CD56(dim) NK subsets from 43 HLA-matched non-T cell-depleted HSCT donor-recipient pairs. The early expansion of CD56(bright) NK cells gradually declined in the posttransplant period but still persisted for at least 1 year and was characterized by the emergence of an unusual CD56(bright)CD16(low) subset with an intermediate maturation profile. The activating receptors NKG2D and NKp46, but also the inhibitory receptor NKG2A, were overexpressed compared with donor CD56(bright) populations. Recipient CD56(bright) NK cells produced higher amounts of IFN-gamma than did their respective donors and were competent for degranulation. Intracellular perforin content was increased in CD56(bright) NK cells as well as in T cells compared with donors. IL-15, the levels of which were increased in the posttransplant period, is a major candidate to mediate these changes. IL-15 serum levels and intracellular T cell perforin were significantly higher in recipients with acute graft-vs-host disease. Altogether, CD56(bright) NK cells postallogeneic HSCT exhibit peculiar phenotypic and functional properties. Functional interactions between this subset and T cells may be important in shaping the immune response after HSCT.

Polyomaviruses KI and WU in immunocompromised patients with respiratory disease.

Polyomaviruses KI (KIPyV) and WU (WUPyV) were recently identified, mainly in respiratory specimens from children. Among 200 patients with respiratory disorders admitted to Saint Louis Hospital, Paris, France, KIPyV was detected in 8% and WUPyV in 1%. KIPyV was significantly more frequent among human stem cell transplant patients (17.8% vs. 5.1%; p = 0.01).

An unusual bipolar primary herpes simplex virus 1 infection.

We describe an atypical primary HSV 1 genital infection with bilateral palmar involvement. Two routes of dissemination of HSV are discussed, self-inoculation and blood dissemination. This case highlights the role of HSV 1 in extragenital pustules in the context of sexually transmitted diseases.

Palivizumab treatment of respiratory syncytial virus infection after allogeneic hematopoietic stem cell transplantation.

Among 40 allogeneic stem cell transplant recipients who developed symptomatic respiratory syncytial virus infection, including 22 patients with lower respiratory tract infection, 19 received palivizumab (9 of whom had upper respiratory tract disease). Palivizumab did not prevent progression to lower respiratory infection and had no impact on the overall survival rate.

Failure of zanamivir therapy for pneumonia in a bone-marrow transplant recipient infected by a zanamivir-sensitive influenza A (H1N1) virus.

Influenza A viruses are responsible for significant morbidity and mortality after bone marrow transplantation. Here we report failure of inhaled zanamivir treatment in a bone-marrow transplant recipient with pneumonia caused by an influenza A (H1N1) virus, although the influenza viruses isolated from bronchoalveolar lavages before and after treatment were clearly found to be sensitive to zanamivir using cell-based and enzymatic assays. Subsequent oral treatment with oseltamivir allowed complete recovery. Poor bioavailability of zanamivir in the peripheral lungs might have been limiting treatment efficacy in such an immunocompromised patient.

Increased incidence of cytomegalovirus retinitis after allogeneic hematopoietic stem cell transplantation.

Six cases of cytomegalovirus retinitis (CMVR) after allogeneic hematopoietic stem cell transplantation were diagnosed between 2002 and 2005 in our center, whereas only one case was diagnosed between 1985 and 2001. Cumulative incidence reaches 2.2%, whereas this complication has been rarely described after hematopoietic stem cell transplantation. We aimed to describe clinical and biologic features of CMVR and search for risk factors associated with CMVR. CMVR was diagnosed on specific funduscopic examination in all patients either on visual symptoms (n=3) or on systematic ophthalmologic examination (n=3). CMVR occurred in the context of unrelated transplantation in patients with profound immune defect and multiple episodes of cytomegalovirus (CMV) reactivation. The combination of a CMV-seropositive recipient and CMV-seronegative donor was the leading risk factor.

Disseminated adenovirus infections after allogeneic hematopoietic stem cell transplantation: incidence, risk factors and outcome.

We analyzed the factors and outcome of patients with disseminated adenovirus infection (dAdV) after allogeneic hematopoeitic stem cell transplantation (HSCT). Thirty patients with dAdV were identified among 620 allogeneic HSCT recipients. Primary diseases were leukemia (n=17), Fanconi anemia (n=12) or others (n=1). Source of stem cells was unrelated in 28 and related in 2 patients. The graft consisted of peripheral blood (n=3), bone marrow (n=12) and unrelated cord-blood (UCB, n=15). Risk factors for dAdV in unrelated HSCT recipients were previous Fanconi disease (p=0.03) and GVHD (p=0.02) in children, and cord blood source of stem cells (p=0.029) and GVHD (0.024) in adults.

Automated quantification of Epstein-Barr Virus in whole blood of hematopoietic stem cell transplant patients using the Abbott m2000 system.

BACKGROUND: Accurate quantification of Epstein-Barr virus (EBV) load in blood is essential for the management of post-transplant lymphoproliferative disorders. The automation of DNA extraction and amplification may improve accuracy and reproducibility. We evaluated the EBV PCR Kit V1 with fully automated DNA extraction and amplification on the m2000 system (Abbott assay). METHODOLOGY: Conversion factor between copies and international units (IU), lower limit of quantification, imprecision and linearity were determined in a whole blood (WB) matrix. Results from 339 clinical WB specimens were compared with a home-brew real-time PCR assay used in our laboratory (in-house assay). RESULTS: The conversion factor between copies and IU was 3.22 copies/IU. The lower limit of quantification (LLQ) was 1000 copies/mL. Intra- and inter-assay coefficients of variation were 3.1% and 7.9% respectively for samples with EBV load higher than the LLQ. The comparison between Abbott assay and in-house assay showed a good concordance (kappa = 0.77). Loads were higher with the Abbott assay (mean difference = 0.62 log10 copies/mL). SIGNIFICANCE: The EBV PCR Kit V1 assay on the m2000 system provides a reliable and easy-to-use method for quantification of EBV DNA in WB.

First HSV-1 non primary genital herpes in two patients.

First HSV-1 genital episodes in HSV-2 infected patients however, had never been demonstrated until the 2 cases we observed. This scarcity could reflect the lower impact of HSV-2 on western populations but questions the existence of cross-protection between viral types.

Assessment of the efficacy and safety of pre-emptive anti-cytomegalovirus (CMV) therapy in HIV-infected patients with CMV viraemia.

A number of studies have demonstrated that cytomegalovirus (CMV) viraemia is a strong predictor for CMV end-organ disease (EOD) and death in HIV-infected patients. We assess the efficacy and safety of pre-emptive anti-CMV therapy (PACT) for preventing these events. We performed a retrospective study of all HIV-infected patients seen in our institution who had detectable CMV viraemia in 2007. Seventy-one patients with advanced HIV disease (median CD4 cell count = 61 cells/mm(3)) were studied. Sixteen patients received PACT (mainly valganciclovir). Patients who received PACT had lower CD4 cell counts and higher blood CMV DNA levels. The cumulative incidence of CMV EOD and death at one year was 44% and 21% in patients with and without PACT, respectively (p = 0.013). Both PACT and high blood CMV DNA levels were significantly associated with CMV EOD and death in unadjusted analysis. In adjusted analyses, only blood CMV DNA levels remained significantly associated with the risk of CMV EOD and death, whereas PACT was associated with a non-significant trend towards reduced CMV EOD or death (hazard ratio: 0.25, p = 0.13). Five patients with PACT experienced severe drug-related adverse events. In conclusion, the use of PACT in HIV-infected patients with CMV viraemia could improve outcome but is associated with significant toxicity.