Real-time automated PCR for early diagnosis and monitoring of cytomegalovirus infection after bone marrow transplantation

ELISPOT assay of interferon-γ secretion for evaluating human cytomegalovirus reactivation risk in allo-HSCT recipients

Human cytomegalovirus (HCMV) is a common cause of significant morbidity and mortality in transplant recipients after allogeneic hematopoietic stem cell transplantation (allo-HSCT). We evaluated interferon-γ (IFN-γ) secretion by HCMV NLV-specific CD8⁺ T cells in HCMV-reactivated allo-HSCT recipients using an enzyme-linked immunospot (ELISPOT) assay at 3 months post-transplantation. Blood samples from 47 recipients were tested for HCMV DNAemia, HCMV pp65 antigenemia, and anti-HCMV immunoglobulins (IgG/IgM) over 3 months post-transplantation. Of the 47 transplant recipients, 26 were HLA-A*02 positive and 21 were HLA-A*02 negative. The results were essentially consistent between the 47 transplant recipients and the HLA-A*02-positive recipients. HCMV DNAemia was not linearly correlated with IFN-γ spot-forming cells (SFCs) counts; IFN-γ SFCs counts did not differ significantly between the HCMV DNAemia-positive and -negative groups, whereas the HCMV-DNA virus loads were inversely correlated with the IFN-γ SFCs counts. HCMV pp65 antigenemia was not linearly correlated with IFN-γ SFCs counts; IFN-γ SFCs counts in the HCMV pp65 antigenemia-positive and -negative groups were similar. More IFN-γ SFCs counts were detected in transplant recipients with high anti-HCMV-IgG antibody titers than in those with low anti-HCMV-IgG titers pre-transplantation in the 47 recipients. Anti-HCMV-IgG antibody titers were positively linearly correlated with IFN-γ SFCs counts in HLA-A*02-positive recipients. The HCMV infection indicators used to monitor HCMV reactivation had different values in transplant recipients. The use of the IFN-γ SFCs counts measured by ELISPOT to evaluate the risk of HCMV reactivation needs further study.

Alphatorquevirus is the most prevalent virus identified in blood from a matched maternal-infant preterm cohort

Objective: To determine the prevalence of virus in a previously uncharacterized matched maternal-infant preterm cohort and test if viral presence or viral load correlate with histologic chorioamnionitis, spontaneous preterm labor or pre-eclampsia.Study Design: Using qRT-PCR/qPCR we tested plasma or whole blood samples from 56 matched maternal and premature infant dyads for: adenovirus, anellovirus (alphatorquevirus and betatorquevirus), cytomegalovirus (CMV), Epstein-Barr virus (EBV), enterovirus, human herpesvirus 6 (HHV6), parechovirus, and parvovirus B19.Result: Viral detection was more common in maternal samples 29/56 (52%) than in cord blood from their infants (4/56 (7%)) (p ≤ .0001). No significant difference in viral load or viral prevalence was identified between pregnancies with and without histologic chorioamnionitis, spontaneous preterm labor or pre-eclampsia.Conclusion: Despite frequent detection of virus in maternal samples, virus was less frequently detected in the infants. Additionally, there was no association of presence or quantity of virus in maternal blood with histologic chorioamnionitis, spontaneous preterm labor or pre-eclampsia in this small, but well-defined cohort. Future studies are necessary to further characterize the role of virus in placental inflammatory states and pregnancy outcomes.

Usefulness of aqueous and vitreous humor analysis in infectious uveitis

OBJECTIVE

To evaluate the role of intraocular fluid analysis as a diagnostic aid for uveitis.

METHODS

Twenty-eight samples (27 patients including 3 HIV-infected patients) with active (n=24) or non-active (n=4) uveitis were submitted to aqueous (AH; n=12) or vitreous humor (VH) analysis (n=16). All samples were analyzed by quantitative PCR for herpes simplex virus (HSV), varicella zoster virus (VZV), cytomegalovirus (CMV), Epstein-Barr virus (EBV) and Toxoplasma gondii.

RESULTS

The positivity of the PCR in AH was 41.7% (5/12), with 50% (2/4) in immunocompetent and 67% (2/3) in HIV+ patients. The positivity of the PCR in VH was 31.2% (5/16), with 13% (1/8) in immunocompetent and 50% (4/8) in immunosuppressed HIV negative patients. The analysis was a determinant in the diagnostic definition in 58% of HA and 50% of VH.

CONCLUSION

Even in posterior uveitis, initial AH analysis may be helpful. A careful formulation of possible clinical diagnosis seems to increase the chance of intraocular sample analysis being meaningful.

Targeting a highly repeated germline DNA sequence for improved real-time PCR-based detection of Ascaris infection in human stool

Background

With the expansion of soil transmitted helminth (STH) intervention efforts and the corresponding decline in infection prevalence, there is an increased need for sensitive and specific STH diagnostic assays. Previously, through next generation sequencing (NGS)-based identification and targeting of non-coding, high copy-number repetitive DNA sequences, we described the development of a panel of improved quantitative real-time PCR (qPCR)-based assays for the detection of Necator americanus, Ancylostoma duodenale, Ancylostoma ceylanicum, Trichuris trichiura, and Strongyloides stercoralis. However, due to the phenomenon of chromosome diminution, a similar assay based on high copy-number repetitive DNA was not developed for the detection of Ascaris lumbricoides. Recently, the publication of a reference-level germline genome sequence for A. lumbricoides has facilitated our development of an improved assay for this human pathogen of vast global importance.

Methodology/Principal findings

Repurposing raw DNA sequence reads from a previously published Illumina-generated, NGS-based A. lumbricoides germline genome sequencing project, we performed a cluster-based repeat analysis utilizing RepeatExplorer2 software. This analysis identified the most prevalent repetitive DNA element of the A. lumbricoides germline genome (AGR, Ascaris germline repeat), which was then used to develop an improved qPCR assay. During experimental validation, this assay demonstrated a fold increase in sensitivity of ~3,100, as determined by relative Cq values, when compared with an assay utilizing a previously published, frequently employed, ribosomal internal transcribed spacer (ITS) DNA target. A comparative analysis of 2,784 field-collected samples was then performed, successfully verifying this improved sensitivity.

Conclusions/Significance

Through analysis of the germline genome sequence of A. lumbricoides, a vastly improved qPCR assay has been developed. This assay, utilizing a high copy-number repeat target found in eggs and embryos (the AGR repeat), will improve prevalence estimates that are fundamental to the programmatic decision-making process, while simultaneously strengthening mathematical models used to examine STH infection rates. Furthermore, through the identification of an optimal target for PCR, future assay development efforts will also benefit, as the identity of the optimized repeat DNA target is likely to remain unchanged despite continued improvement in PCR-based diagnostic technologies.

With an at-risk population in the billions, Ascaris lumbricoides is a pathogen of great global importance. In recent years, efforts to control the spread of this parasitic helminth have expanded, resulting in declining infection rates and worm burdens in some regions. While immeasurably important for global health, these declines have also served to expose the shortcomings of traditional diagnostic methods, as low-levels of pathogen generate a need for more sensitive tools, and microscopy-based techniques are proving ill-suited to the task at hand. Thankfully, improved sensitivity can be achieved through the careful selection of optimal repetitive DNA targets for PCR. However, previous attempts to identify such targets in A. lumbricoides were unsuccessful, largely due to chromosome diminution, an unusual phenomenon occurring in the Ascaridida, whereby large portions of the germline genome are reproducibly eliminated during early development, resulting in their absence in larvae or adult worms. As the stool-based molecular diagnosis of A. lumbricoides infection is primarily dependent upon the identification of egg-derived DNA, utilizing genomic DNA from adult worms for molecular target selection eliminates germline candidates and results in suboptimal target sequence choices. Recently, the publication of a pre-diminution germline genome of A. lumbricoides has provided us with an opportunity to re-evaluate target selection, facilitating the development of a novel quantitative real-time PCR assay with greatly improved sensitivity (~3100-fold as determined by relative Cq value) over previously developed assays that were based on ribosomal repeat DNA sequences with lower copy numbers.

Identification of clinically relevant cytomegalovirus infections in patients with inflammatory bowel disease

Several lines of evidence indicate that cytomegalovirus infection can be substantially associated with onset of inflammatory bowel disease, especially in patients refractory to immunosuppressive treatment. As cytomegalovirus is widely spread in the population, here we present a quantitative detection system suitable to differentiate clinically relevant cytomegalovirus infection from common latent cytomegalovirus. Using a quantitative real-time PCR approach, cytomegalovirus viral load was evaluated in 917 formalin-fixed and paraffin-embedded colon biopsy samples of 136 patients diagnosed with inflammatory bowel disease. Besides initial cytomegalovirus testing, the PCR system was also used to monitor therapy response after antiviral treatment. Cytomegalovirus DNA was detected in 37 patients (27%) with varying viral loads ranging from 5 to 8.7 × 10⁵ copies/10⁵ cells. Thereof, 13 patients (35%) received an antiviral treatment with 12 of them going into remission (92%). Later, five patients displayed a relapse and three patients who agreed to restart antiviral treatment again showed positive therapy response. A retrospective comparison of viral loads with antiviral therapy response revealed a threshold of 600 cytomegalovirus copies/10⁵ cells as indicative for clinically relevant infection. Of note, sensitivity of cytomegalovirus detection by immunohistochemistry was found to be insufficient to reliably identify antiviral therapy responders. In conclusion, quantitative real-time PCR using formalin-fixed biopsy samples is suitable for detection of cytomegalovirus infection in tissue samples of patients with inflammatory bowel disease. Moreover, it allows the definition of a viral load threshold, predictive for clinical relevance concerning antiviral therapy response.

Colonic cytomegalovirus detection by mucosal PCR and antiviral therapy in ulcerative colitis

BACKGROUND

We aimed to identify the risk factors associated with colonic cytomegalovirus (CMV) infection in ulcerative colitis (UC) and to compare the clinical course between antiviral therapy-treated and -untreated groups in mucosal CMV-polymerase chain reaction (PCR) -positive cases.

METHODS

We retrospectively selected 46 UC patients (>15 years old) in active phase who underwent colonoscopy with biopsy and were analyzed for CMV infection by mucosal PCR between October 2011 and December 2015 at our institution. Colonic CMV in inflamed mucosa was detected using quantitative real-time PCR. The clinical course was evaluated, including need for drug therapy/surgery or drug therapy intensification. In addition, we evaluated the clinical course between CMV-DNA- cases and CMV-DNA+ cases with low viral load.

RESULTS

At baseline, CMV-DNA+ patients were significantly older, had higher endoscopic scores, and required higher corticosteroid doses during the past 4 weeks than CMV-DNA- patients (p< 0.05). No significant differences were observed in disease duration, disease distribution, laboratory data, or use of other medication between CMV-DNA+ and CMV-DNA- patients. In the anti-CMV-treated group with a median (range) DNA load of 16,000 (9,000-36,400), 3patients achieved remission without additional UC therapy, 2 required additional UC therapy, and 1 required colectomy despite azathioprine and infliximab therapy. In the CMV-untreated group with a median (range) DNA load of 919 (157-5,480), all patients achieved remission with UC therapy alone. No significant difference was observed in the clinical course between CMV-DNA- cases and CMV-DNA+ cases with low viral loads.

CONCLUSIONS

Aging, endoscopic UC activity, and corticosteroid dose predispose to colonic CMV infection, as determined by mucosal PCR, in UC. UC treatment without anti-CMV therapy may be warranted, particularly in patients with low-load CMV-DNA. Anti-CMV therapy alone does not always achieve clinical response in UC even in cases with high-load PCR.

Diagnostic test accuracy of antigenaemia assay for PCR-proven cytomegalovirus infection-systematic review and meta-analysis

OBJECTIVES

We aimed to assess diagnostic test accuracy of antigenaemia assay for PCR-proven cytomegalovirus (CMV) infection.

METHODS

We systematically searched studies that provide data both on sensitivity and specificity of the CMV antigenaemia assay using the PCR as the reference standard. Adults, children, infants, individuals who were immunocompromised for any reason, symptomatic patients and asymptomatic individuals were all included. A hierarchical summary receiver operating characteristics model was used for diagnostic meta-analysis. Study quality was assessed by Revised Tool for the Quality Assessment of Diagnostic Accuracy Studies. Protocol registration identification is CRD42016035892.

RESULTS

We identified 75 eligible articles including 9058 CMV PCR-positive individuals and 22 232 PCR-negative individuals. The diagnostic odds ratio for positive antigenaemia was 30 (95% CI 24-38, I² = 28%) and the area under the hierarchical summary receiver operating characteristic curve was 0.86 (95% CI 0.83-0.88). The summary estimates of sensitivity and specificity were 0.65 (95% CI 0.59-0.70) and 0.94 (95% CI 0.93-0.95), respectively. The positive likelihood ratio of 10.9 (95% CI 8.5-14.0) suggested that a positive result from the antigenaemia assay greatly increased the probability of PCR-proven CMV infection, but a negative likelihood ratio of 0.38 (95% CI 0.32-0.44) indicated that a negative result led to a small decrease in the probability of PCR-proven CMV infection. Sensitivity and subgroup analyses replicated these results.

CONCLUSIONS

The antigenaemia assay overlooked 35% of PCR-proven CMV infections; hence, a negative result of an antigenaemia assay could not rule out a CMV infection.

Viruses comprise an extensive pool of mobile genetic elements in eukaryote cell cultures and human clinical samples

Viruses shape a diversity of ecosystems by modulating their microbial, eukaryotic, or plant host metabolism. The complexity of virus-host interaction networks is progressively fathomed by novel metagenomic approaches. By using a novel metagenomic method, we explored the virome in mammalian cell cultures and clinical samples to identify an extensive pool of mobile genetic elements in all of these ecosystems. Despite aseptic treatment, cell cultures harbored extensive and diverse phage populations with a high abundance of as yet unknown and uncharacterized viruses (viral dark matter). Unknown phages also predominated in the oropharynx and urine of healthy individuals and patients infected with cytomegalovirus despite demonstration of active cytomegalovirus replication. The novelty of viral sequences correlated primarily with the individual evaluated, whereas relative abundance of encoded protein functions was associated with the ecologic niches probed. Together, these observations demonstrate the extensive presence of viral dark matter in human and artificial ecosystems.-Thannesberger, J., Hellinger, H.-J., Klymiuk, I., Kastner, M.-T., Rieder, F. J. J., Schneider, M., Fister, S., Lion, T., Kosulin, K., Laengle, J., Bergmann, M., Rattei, T., Steininger, C. Viruses comprise an extensive pool of mobile genetic elements in eukaryote cell cultures and human clinical samples.

Cytomegalovirus Pneumonia in Patients with Rheumatic Diseases After Immunosuppressive Therapy: A Single Center Study in China

Background:

Rheumatic diseases involve multiple organs that are affected by immunological mechanisms. Treatment with corticosteroids and immunosuppressive agents may also increase the frequency of infection. Cytomegalovirus (CMV) is a widespread herpes virus and a well-recognized pathogen, which causes an opportunistic and potentially fatal infection in immunocompromised patients. This retrospective study aimed to investigate the clinical and laboratory characteristics of CMV pneumonia in patients with rheumatic diseases after immunosuppressive therapy in a single center in Shanghai, China.

Methods:

Eight hundred and thirty-four patients with rheumatic diseases who had undergone CMV-DNA viral load tests were included, and the medical records of 142 patients who were positive for CMV-DNA in plasma samples were evaluated. GraphPad Prism version 5.013 (San Diego, CA, USA) was used to conduct statistical analysis. The correlation between CMV-DNA viral loads and lymphocyte counts was assessed using the Spearman rank correlation coefficient test. Significance between qualitative data was analyzed using Pearson's Chi-squared test. The cut-off thresholds for CMV-DNA viral load and lymphocyte count were determined by receiver operating characteristic (ROC) curve analysis.

Results:

One hundred and forty-two patients had positive CMV viral load tests. Of these 142 patients, 73 patients with CMV pneumonia were regarded as symptomatic, and the other 69 were asymptomatic. The symptomatic group received higher doses of prednisolone (PSL) and more frequently immunosuppressants than the asymptomatic group (P < 0.01). The symptomatic group had lower lymphocyte counts, especially CD⁴⁺ T-cells, than the asymptomatic group (P < 0.01). By ROC curve analysis, when CD⁴⁺ T-cell count was <0.39 × 10⁹/L, patients with rheumatic diseases were at high risk for symptomatic CMV infection. The CMV-DNA load was significantly higher in the symptomatic patients than that in asymptomatic patients (P < 0.01; threshold viral loads: 1.75 × 10⁴ copies/ml). Seven patients had a fatal outcome, and they had lower peripheral lymphocyte counts (P < 0.01), including CD4⁺ and CD⁸⁺ T-cells (P < 0.01).

Conclusions:

When CD⁴⁺ T-cell count is <0.39 × 10⁹/L, patients are at high risk for pulmonary CMV infection. Patients are prone to be symptomatic with CMV-DNA load >1.75 × 10⁴ copies/ml. Lymphopenia (especially CD⁴⁺ T-cells), presence of symptoms, and other infections, especially fungal infection, are significant risk factors for poor outcome, and a higher PSL dosage combined with immunosuppressants may predict CMV pneumonia.

PCR detection of human herpesviruses in colonic mucosa of individuals with inflammatory bowel disease: Comparison with individuals with immunocompetency and HIV infection

BACKGROUND

Detection of human herpesviruses (HHVs) other than cytomegalovirus (CMV) in colonic mucosa of individuals with inflammatory bowel disease (IBD) remains unknown. This study identified eight HHVs in the colonic mucosa of individuals with IBD and compared the results with immunocompetent and human immunodeficiency virus (HIV)-infected individuals.

METHODS

A total of 89 individuals who had colorectal ulcer on colonoscopy were enrolled: 26 with immunocompetency (n = 26), 41 with IBD, and 22 with HIV infection. We examined the colonic ulcers for the presence of eight HHVs-herpes simplex virus (HSV)-1/2, varicella zoster virus (VZV), CMV, Epstein-Barr virus (EBV), HHV-6, HHV-7, and HHV-8-using mucosal PCR.

RESULTS

The IBD group had positivity rates of 0%, 0%, 0%, 53.7%, 24.4%, 39%, 39%, and 0% for HSV-1, HSV-2, VZV, EBV, CMV, HHV-6, HHV-7, and HHV-8, respectively. The positivity rates of EBV and CMV in colonic mucosa increased significantly in the order of the immunocompetent, IBD, and HIV groups (EBV: 23.1%, 53.7%, 72.7%, P for trend = 0.0005; CMV, 7.7%, 24.4%, 54.5%, P for trend = 0.0003, respectively), but no increase was found in the other HHVs. Median mucosal EBV DNA values in the immunocompetent, IBD, and HIV groups were 0, 76, and 287 copies/μg DNA, respectively (P for trend = 0.002). Corresponding median mucosal CMV DNA values were 0, 0, and 17 copies/μg DNA (P for trend = 0.0001). There was no significant difference in the positivity rates of the eight HHVs between ulcerative colitis and Crohn's disease.

CONCLUSION

The HHVs of EBV, CMV, HHV-6, and HHV-7, but not of HSV-1, HSV-2, VZV, or HHV-8, were identified in the colonic mucosa of IBD individuals. EBV and CMV in colonic mucosa was correlated with host immune status in increasing order of immunocompetent, IBD, and HIV-infected individuals.

Absence of Cytomegalovirus in Glioblastoma and Other High-grade Gliomas by Real-time PCR, Immunohistochemistry, and In Situ Hybridization

Purpose: Reports of cytomegalovirus (CMV) detection in high-grade gliomas (HGG)/glioblastoma have been conflicting. We undertook a comprehensive approach to determine the presence or absence of CMV in tissue, plasma, and serum of HGG patients.Experimental Design: In a retrospective arm, 25 fresh frozen tissues from glioblastoma patients were tested for CMV by real-time PCR. Tissue microarrays from 70 HGG patients were tested by IHC and 20 formalin-fixed paraffin-embedded (FFPE) glioblastoma tissues by IHC and chromogenic in situ hybridization (CISH), targeting CMV-encoded IE1/2 and pp65. In a prospective arm, 18 patients with newly diagnosed HGG provided tissue and blood samples.Results: All retrospectively collected tissues were negative for CMV by all methods. In the prospective cohort, 18 patients with newly diagnosed HGG provided blood samples at the time of diagnosis and during follow-up. Of 38 plasma specimens, CMV DNA was detected in 3 of 18 samples at baseline and 1 of 20 follow-up samples. Serum CMV IgG was positive in 8 of 15 (53%) of patients. Among the FFPE samples tested in the prospective arm, all were negative for CMV by IHC, CISH, and PCR.Conclusions: Utilizing 6 highly sensitive assays with three orthogonal technologies on multiple specimens and specimen types, no evidence for CMV in glioblastoma tissues was found. Our findings call for multicenter blinded analyses of samples collected from different geographical areas with agreed upon study designs and determination of causality or lack thereof of CMV in HGG/glioblastoma for future guidance on the necessary antiviral and/or CMV-based therapies. Clin Cancer Res; 23(12); 3150-7. ©2016 AACR.

Targeted preemptive therapy according to perceived risk of CMV infection after kidney transplantation

Background

Methods

Results

Conclusion

Asymptomatic congenital cytomegalovirus infection with neurological sequelae: A retrospective study using umbilical cord

BACKGROUND

Congenital cytomegalovirus (CMV) infection causes various neurological sequelae. However, most infected infants are asymptomatic at birth, and retrospective diagnosis is difficult beyond the neonatal period.

OBJECTIVE

This study aimed to investigate the aspects of neurological sequelae associated with asymptomatic congenital CMV infection.

METHODS

We retrospectively analyzed 182 patients who were suspected of having asymptomatic congenital CMV infection with neurological symptoms in Japan. Congenital CMV infection was diagnosed by quantitative polymerase chain reaction amplification of CMV from dried umbilical cord DNA.

RESULTS

Fifty-nine patients (32.4%) who tested positive for CMV were confirmed as having congenital CMV infection. Among 54 congenital CMV patients, major neurological symptoms included intellectual disability (n=51, 94.4%), hearing impairment (n=36, 66.7%) and cerebral palsy (n=21, 38.9%), while microcephaly (n=16, 29.6%) and epilepsy (n=14, 25.9%) were less common. In a brain magnetic resonance imaging (MRI) study, cortical dysplasia was observed in 27 CMV-positive patients (50.0%), and all patients (100%) had cerebral white matter (WM) abnormality. Intracranial calcification was detected by CT in 16 (48.5%) of 33 CMV-positive patients. Cerebral palsy, cortical dysplasia and a WM abnormality with a diffuse pattern were associated with marked intellectual disability.

CONCLUSIONS

Brain MRI investigations are important for making a diagnosis and formulating an intellectual prognosis. Analysis of umbilical cord tissue represents a unique and useful way to retrospectively diagnose congenital CMV infection.

How to develop an in-house real-time quantitative cytomegalovirus polymerase chain reaction: Insights from a cancer centre in Eastern India

Development of a reliable, cost-effective cytomegalovirus quantitative polymerase chain reaction (QPCR) is a priority for developing countries. Manufactured kits are expensive, and availability can be inconsistent. Development of an in-house QPCR kit that is reliable and quality assured requires significant effort and initial investment. However, the rewards of such an enterprise are manifold and include an in-depth understanding of molecular reactions, and expertise in the development of further low-cost molecular kits. The experience of an oncology centre in Eastern India has been shared. Hopefully, this would provide a brief roadmap for such an initiative. Staff with adequate understanding of molecular processes are essential along with vital infrastructure for molecular research and development.

Genetic variation in Micro-RNA genes of host genome affects clinical manifestation of symptomatic Human Cytomegalovirus infection

BACKGROUND

Micro-RNAs are implicated in various physiological and pathologic processes. In this study, we tested whether Micro-RNA gene variants of host-genome affect clinical manifestation of symptomatic HCMV infection.

METHODOLOGY

HCMV infection was detected by fluorescent PCR and immuno-histochemistry. The detection of genetic variants of four studied Micro-RNA tag-SNPs was done through PCR-RFLP assay and validated with DNA sequencing.

RESULTS

We observed an increased risk ranged from 3-folds to 5-folds among symptomatic HCMV cases for mutant genotype of rs2910164 (crude OR=3.11, p=0.009 and adjusted OR=3.25, p=0.007), rs11614913 (crude OR=3.20, p=0.006 and adjusted OR=3.48, p=0.004) and rs3746444 (crude OR=4.91, p=0.002 and adjusted OR=5.28, p=0.002) tag-SNPs. Interestingly, all the tag-SNPs that were significant after multiple comparisons at a FDR of 5% in symptomatic HCMV cases remained significant even after bootstrap analysis, providing internal validation to these results. Multifactor Dimensionality Reduction (MDR) analysis revealed 5-folds increased risk for symptomatic HCMV cases under the four-factor model (rs2910164, rs2292832, rs11614913 and rs3746444).

CONCLUSIONS

These results suggest that Micro-RNA gene variants of host-genome may affect clinical manifestation of symptomatic HCMV infection.

Diagnostic utility of quantitative plasma cytomegalovirus DNA PCR for cytomegalovirus end-organ diseases in patients with HIV-1 infection

OBJECTIVE

To investigate the diagnostic value of quantitative plasma cytomegalovirus (CMV)-DNA polymerase chain reaction (PCR) for CMV end-organ diseases (CMV-EOD) in patients with HIV-1 infection.

DESIGN

Single-center cross-sectional study.

METHODS

The study subjects were HIV-1-infected patients with CD4 ≤200 per microliter, who had undergone ophthalmologic examination with plasma CMV-DNA PCR measured within 7 days. CMV retinitis and other CMV-EOD were diagnosed according to the ACTG criteria. PCR value was converted into the WHO international standard.

RESULTS

CMV retinitis and all CMV-EOD were diagnosed in 23 (5%) and 37 (8%) of the 461 study patients, respectively. CMV-DNA was undetectable (<185 IU/mL) in 2 patients with CMV retinitis and 1 with encephalitis. The area under the receiver operating characteristic curve of CMV-DNA for CMV retinitis and all CMV-EOD were 0.80 [95% confidence interval (CI): 0.71 to 0.89] and 0.82 (0.75 to 0.89), respectively. The sensitivity, specificity, positive predictive value, and negative predictive value for each cutoff value of CMV-DNA were as follows: for CMV retinitis, ≥10,086 IU/mL: 26.1%, 94.1%, 18.8%, 96%; ≥2946 IU/mL; 56.5%, 86.8%, 18.3%, 97.4%; ≥959 IU/mL; 60.9%, 78.1%, 12.7%, 97.4%; detectable CMV-DNA (≥185 IU/mL): 91.3%, 48.2%, 8.5%, 99.1%; for all CMV-EOD: ≥10,086 IU/mL: 32.4%, 95.3%, 37.5%, 94.2%; ≥2946 IU/mL; 54.1%, 88%, 28.2%, 95.6%; ≥959 IU/mL; 62.2%, 79.5%, 20.9%, 96%; detectable CMV-DNA; 91.9%, 49.5%, 13.7%, 98.6%.

CONCLUSIONS

Plasma CMV-DNA PCR has a high diagnostic value for both CMV retinitis and all CMV-EOD in patients with advanced HIV-1 infection. A cutoff value of CMV-DNA ≥10,086 IU/mL and ≥2946 IU/mL yields high specificity, whereas undetectable CMV-DNA load (<185 IU/mL) likely rules out CMV-EOD.

An update on the management and prevention of cytomegalovirus infection following allogeneic hematopoietic stem cell transplantation

ABSTRACT 

A significant progress has been made in deciphering critical aspects of the biology and immunology of CMV infection in the allogeneic stem cell transplantation setting. Genetic traits predisposing to active CMV infection and CMV end-organ disease have begun to be delineated. Reliable molecular assays for CMV DNA load quantitation in body fluids have been developed. Elucidation of immune mechanisms affording control of CMV infection will help to improve the management of active CMV infection. Finally, the advent of new CMV-specific antivirals and promising vaccine prototypes as well as the development of fine procedures for large-scale ex vivo generation of functional CMV-specific T cells for adoptive T cell transfer therapies will certainly minimize the negative impact of CMV on survival in these patients.

Characterization of cytomegalovirus and epstein-barr virus infection in cervical lesions in Portugal

Infection by high-risk types of human papillomavirus (HPV) is considered necessary but not sufficient for the development of cervical cancer. Previous studies suggested that cytomegalovirus (CMV) and Epstein-barr virus (EBV) could be co-factors of HPV-associated carcinogenesis. The aim of this study was to characterize the prevalence of CMV and EBV and evaluate its association with the development cervical lesions in Portugal. The prevalence of CMV and EBV infections was determined by real-time PCR in 89 cervical samples from women with different histological lesions, who attended the Portuguese Institute of Oncology of Porto. This study revealed an overall prevalence of 4.5% for CMV and 10.1% for EBV. Age-stratified analysis revealed that CMV infection was present in individuals <30 and >60 years old, while EBV infection was present in all age groups. CMV was detected in 9.5% of low-grade lesions and in 22.2% of in situ/invasive carcinomas, while EBV infection was found in all different types of lesions. In addition, data revealed that CMV infection was associated with an increased risk of in situ/invasive carcinoma development (OR=1.28; P=0.035). The study reveals a low prevalence for both viruses; nevertheless, these results are important for knowledge on the shedding of EBV and CMV in cervical samples.

Donor T-cell chimerism and early post-transplant cytomegalovirus viremia in patients treated with myeloablative allogeneic hematopoietic stem cell transplant

BACKGROUND

Cytomegalovirus (CMV) is a common infection after myeloablative allogeneic hematopoietic stem cell transplant (M-alloHSCT). Achievement of complete donor T-cell chimerism (CDC-T) post transplant is a measure of immune reconstitution. We investigated the association between CDC-T post M-alloHSCT and the incidence of CMV viremia.

METHODS

We retrospectively reviewed all CMV and chimerism results of 47 patients for the first 6 months post M-alloHSCT. CDC-T was analyzed as a time-varying covariate for association with post M-alloHSCT CMV viremia.

RESULTS

CMV viremia occurred in 15 (32%) and CDC-T was achieved in 38 (81%) recipients within the first 6 months post M-alloHSCT. On univariable analysis, increased CMV viremia was seen among patients with CDC-T (hazard ratio 2.81 [P = 0.07, 95% confidence interval = 0.93-8.52]). A 30-day landmark analysis showed that the incidence of CMV viremia at 6 months (regardless of recipient CMV serostatus) was 50% among those who had achieved CDC-T by day 30, and 23% among those who had not (P = 0.06).

CONCLUSION

We conclude that shorter time to CDC-T may be associated with higher risk of CMV viremia. If confirmed in a larger cohort, this might be a marker for risk stratification in the management of CMV in this population.

Determination, validation and standardization of a CMV DNA cut-off value in plasma for preemptive treatment of CMV infection in solid organ transplant recipients at lower risk for CMV infection

BACKGROUND

Valganciclovir preemptive therapy guided by the viral load is the current strategy recommended for preventing CMV disease in CMV-seropositive Solid Organ Transplant Recipients (SOTR) at lower risk for developing CMV infection. However, universal viral load cut-off has not been established for initiating therapy.

OBJECTIVES

Our goal was to define and validate a standardized cut-off determined in plasma by real-time PCR assay for initiating preemptive therapy in this population.

STUDY DESIGN

A prospective cohort study of consecutive cases of CMV-seropositive SOTR was carried out. The cut-off value was determined in a derivation cohort and was validated in the validation cohort. Viral loads were determined using the Quant CMV LightCycler 2.0 real-time PCR System (Roche Applied Science) and results were standardized using the WHO International Standard for human CMV.

RESULTS

A viral load of 3983 IU/ml (2600 copies/ml) was established as the optimal cut-off for initiating preemptive therapy in a cohort of 141 patients with 982 tests and validated in a cohort of 252 recipients with a total of 2022 test. This cut-off had a 99.6% NPV indicating that the great majority of patients at lower risk will not develop CMV disease without specific antiviral therapy. The high sensitivity and specificity (89.9% and 88.9%, respectively) and the relatively small numbers of patients with CMV disease confirm that real-time PCR was optimal.

CONCLUSIONS

We have established a cut-off viral load for starting preemptive therapy for CMV-seropositive SOT recipients. Our results emphasized the importance of a mandatory follow-up protocol for CMV-seropositive patients receiving preemptive treatment.

Unusual ribbon-like periventricular heterotopia with congenital cataracts in a Japanese girl

Periventricular heterotopia (PH), clumps of neurons mislocated beside the ventricle, is caused by failure to initiate migration during embryogenesis. We report on a 32-month-old Japanese girl with a unique subtype of PH, namely ribbon-like PH. The patient presented with severe psychomotor developmental delay, intractable epilepsy, and congenital cataracts and developed West syndrome phenotype. Brain magnetic resonance imaging revealed a unique undulating form of PH, categorized as ribbon-like PH, and other brain malformations including simplified gyri and dysgenesis of the corpus callosum. There was no evidence of prenatal TORCH infection or associated syndrome. Array-based comparative genomic hybridization revealed no chromosomal rearrangements. Genetic analyses of the FLNA, DCX, ARX, LIS1, and TUBA1A genes showed no mutations. Although little is known about ribbon-like PH, the clinical manifestations in our patient clearly differed from those in other reported patients.

Comparison of a UL111a real-time PCR and pp65 antigenemia for the detection of cytomegalovirus

Surveillance of cytomegalovirus (CMV) replication in transplant patients is crucial for the success of transplantation. To compare a CMV pp65 antigenemia (pp65Ag) and a quantitative real-time PCR targeting the CMV-UL111a (UL111aPCR), all whole blood samples taken between July 2008 and October 2009 were identified which had been analyzed prospectively by both assays in parallel. Discordant results were re-analyzed using a published CMV duplex PCR targeting regions UL55 and UL123exon4. Of 720 samples from 81 transplant patients, CMV replication was detected in 244 specimens (34%) by the UL111aPCR (median, 1,019 geq/ml), compared to 113 (16%) detected by the pp65Ag (median, 2/250,000 leukocytes). Concordant UL111aPCR/pp65Ag results were obtained in 561 (78%) samples, being positive in 99 (14%), and negative in 462 (64%). As a rule of thumb, 1 pp65Ag-positive cell per 250,000 leukocytes corresponded to 1,000 geq/ml CMV DNA of whole blood. Discordant results were found in 159 samples (22%), being UL111aPCR-positive/pp65Ag-negative in 145 (91%; median, 650 geq/ml), or UL111aPCR-negative/pp65Ag-positive in 14 (9%; median, 1/250,000 cells). Using the duplex PCR targeting the CMV UL55 and the UL123-exon4 genes, 131 of 139 (94%) discordant UL111aPCR-positives (median UL111aPCR, 639 geq/ml; median UL55PCR, 715 geq/ml; median UL123PCR, 1,103 geq/ml) were confirmed. Of 14 discordant pp65Ag-positives, duplex PCR was also negative in 8, and of low copy number in 6. Thus, CMV UL111aPCR provides more sensitive quantitation of CMV replication than pp65Ag, however, discordant results can occur at very low viral loads.

Clinical usefulness of plasma quantitative polymerase chain reaction assay: diagnosis of cytomegalovirus infection in kidney transplant recipients

BACKGROUND

Preemptive therapy is used to prevent cytomegalovirus (CMV) disease in transplant recipients. The CMV antigenemia assay, which has been commonly used as a predictive marker for preemptive therapy, requires intensive labor and immediate processing. We compared the cutoff value of plasma CMV polymerase chain reaction (PCR) with CMV antigenemia in kidney transplant recipients.

METHODS

We compared two diagnostic methods for CMV infection in kidney transplant recipients: quantitative PCR (qPCR) versus antigenemia. We evaluated the optimal cutoff value of plasma CMV qPCR by using receiver-operating characteristic curves for specific antigenemia values. All kidney transplant recipients from January 2004 to January 2005 were enrolled and followed with CMV antigenemia and plasma CMV qPCR.

RESULTS

The analyses were performed on 899 samples collected from 111 patients in the early posttransplant period, matching 84.1% of patients for the results of CMV antigenemia and plasma CMV qPCR. For patients with symptomatic CMV infection and disease, who showed ≥25 positive cells in the antigenemia assay, the cutoff value for qPCR was 17.8 copies/μL with a sensitivity of 97.1%, a specificity of 89.1%, and a positive predictive value of 26.6%.

CONCLUSIONS

Diagnostic assays for CMV such as CMV antigenemia and quantitative plasma PCR, showed similar diagnostic values. They are the methods of choice for the diagnosis and monitoring of active CMV infection after kidney transplantation. However, because of the relatively low positive predictive value of qPCR, this test may lead to unnecessary preemptive treatment in kidney transplant recipients.

Transmission of cytomegalovirus (CMV) infection by leukoreduced blood products not tested for CMV antibodies: a single-center prospective study in high-risk patients undergoing allogeneic hematopoietic stem cell transplantation (CME)

BACKGROUND

Measures to prevent transfusion-transmitted cytomegalovirus (TT-CMV) infection after hematopoietic stem cell transplantation (HSCT) include transfusion of CMV antibody-negative blood units and/or transfusion of leukoreduced cellular blood products. We assessed the incidence of TT-CMV in CMV-seronegative patients receiving CMV-seronegative HSC transplants, who were transfused with leukoreduced cellular blood products not tested for anti-CMV.

STUDY DESIGN AND METHODS

In a prospective observational study between 1999 and 2009, all HSCT patients received leukoreduced cellular blood products not tested for anti-CMV. Patients were screened for CMV serostatus and CMV-negative recipients of CMV-negative transplants were systematically monitored for TT-CMV clinically and by CMV nucleic acid testing. Anti-CMV antibodies (immunoglobulin [Ig]G and IgM) were assessed after three time intervals (Interval 1, study inclusion to Day +30 after HSCT; Interval 2, Day +30-Day +100; Interval 3, after Day +100).

RESULTS

Among 142 patients treated with allogeneic HSCT, 23 CMV-negative donor-patient pairs were identified. These 23 patients received 1847 blood products from 3180 donors. All patients remained negative for CMV DNA and none developed CMV-associated clinical complications. This results in a risk for TT-CMV per donor exposure of 0% (95% confidence interval, 0.0%-0.12%). However, 17 of 23 patients seroconverted for anti-CMV IgG, but none for anti-CMV IgM. CMV IgG seroconverters received significantly more transfusions per week than nonconverters.

CONCLUSION

The risk of TT-CMV is low in high-risk CMV(neg/neg) HSCT patients transfused with leukoreduced blood products not tested for anti-CMV. The cause of anti-CMV IgG seroconversion is most likely passive antibody transmission by blood products.

Cytomegalovirus DNA quantification using an automated platform for nucleic acid extraction and real-time PCR assay setup

Analytical performance characteristics of the QIAsymphony RGQ system with artus cytomegalovirus (CMV) reagents were determined. Measurable range spanned 2.0 to ≥ 7.0 log(10) copies/ml. The detection limit was 23 copies/ml. Intrarun and interrun coefficients of variation were ≤ 2.1% at 3.0 and 5.0 log(10) copies/ml. In clinical specimens, RGQ values were ~0.2 log(10) copies/ml higher than those in an assay using a BioRobot M48 extraction/manual reaction setup/7500 Real-Time PCR instrument. No cross-contamination was observed.

Reactivations of cytomegalovirus, human herpes virus 6, and Epstein-Barr virus differ with respect to risk factors and clinical outcome after hematopoietic stem cell transplantation

One hundred two recipients of hematopoietic stem cell transplants (HSCTs) 45, from siblings and 57 from matched unrelated donors, were followed for cytomegalovirus (CMV), human herpes virus (HHV) 6, and Epstein-Barr Virus (EBV) reactivation by quantitative polymerase chain reaction in the context of immunologic reconstitution and posttransplantation complications. CMV, EBV, and HHV6 DNA copies (>100 copies/10(5) cells) were detected in 34%, 27%, and 26% of patients, respectively. The presence of 100 copies of EBV or CMV was associated with posttransplant complications: 29/66 versus 6/36 (P<.01) or 24/66 versus 4/36 (P=.01). CMV reactivation was more frequent among patients with acute graft-versus-host disease grade≥I: 17/35 versus 18/67 (P<.05). Older patient age of adults>16 year (2/16 versus 33/86; P<.05) and, to a lesser extent, CMV IgG positivity before HSCT (34/84 versus 1/10; P=.08) or an HLA-mismatched graft (9/16 versus 26/86; P=.08) constituted risk factors for CMV reactivation, which resulted in a higher rate of bacterial pneumonia (7/11 versus 28/91; P=.04). EBV reactivation risk was associated with donor EBV IgG seropositivity (28/84 versus 0/10; P=.03) and donor female gender (18/47 versus 10/55; P=.03). In contrast to EBV and CMV, EBV reactivation itself was associated with encephalitis (5/8 versus 23/94; P=.013), which was also seen as a trend among HHV6 reactivations (8/8 versus 46/94; P=.08). Multivariate analysis demonstrated that these factors play independent roles in the reactivation of the investigated herpes viruses.

Saliva as a source of HCMV DNA in allogeneic stem cell transplantation patients

OBJECTIVE

The purpose of this study was to investigate the use of saliva for the identification of human cytomegalovirus (HCMV) in allogeneic hematopoietic stem cell transplant patients by real time PCR compared with blood.

MATERIALS AND METHODS

Saliva and blood samples were sampled weekly in 30 allogeneic hematopoietic stem cell transplant patients until 100 days after transplant. Total genomic DNA, extracted from saliva and whole-blood samples, was used for HCMV real time PCR. Nonparametric tests were performed, and P value <or=0.05 was considered statistically significant.

RESULTS

Human cytomegalovirus DNA load in saliva showed a high correlation with viral DNA in the blood (R = 0.858; P < 0.0001). Blood DNA levels also correlated with HCMV antigenemia (R = 0.773; P < 0.0001). The HCMV levels in saliva (P = 0.015) and blood (P = 0.008) showed higher levels at the beginning of antiviral treatment, with clear reduction after this period. Saliva showed earlier HCMV reactivation than blood detected by real time PCR and antigenemia assay in 11 out of 22 subjects.

CONCLUSIONS

This study shows that the real time PCR test could be useful to identify HCMV DNA in saliva and to monitor patients at risk of cytomegalovirus disease after allogeneic hematopoietic stem cell transplant. However, further studies are necessary to confirm this data.

Surveillance of active human cytomegalovirus infection in hematopoietic stem cell transplantation (HLA sibling identical donor): search for optimal cutoff value by real-time PCR

BACKGROUND

Human cytomegalovirus (CMV) infection still causes significant morbidity and mortality after allogeneic hematopoietic stem cell transplantation (HSCT). Therefore, it is extremely important to diagnosis and monitor active CMV infection in HSCT patients, defining the CMV DNA levels of virus replication that warrant intervention with antiviral agents in order to accurately prevent CMV disease and further related complications.

METHODS

During the first 150 days after allogeneic HSTC, thirty patients were monitored weekly for active CMV infection by pp65 antigenemia, nested-PCR and real-time PCR assays. Receiver operating characteristic (ROC) plot analysis was performed to determine a threshold value of the CMV DNA load by real-time PCR.

RESULTS

Using ROC curves, the optimal cutoff value by real-time PCR was 418.4 copies/104 PBL (sensitivity, 71.4%; specificity, 89.7%). Twenty seven (90%) of the 30 analyzed patients had active CMV infection and two (6.7%) developed CMV disease. Eleven (40.7%) of these 27 patients had acute GVHD, 18 (66.7%) had opportunistic infection, 5 (18.5%) had chronic rejection and 11 (40.7%) died - one died of CMV disease associated with GVHD and bacterial infection.

CONCLUSIONS

The low incidence of CMV disease in HSCT recipients in our study attests to the efficacy of CMV surveillance based on clinical routine assay. The quantification of CMV DNA load using real-time PCR appears to be applicable to the clinical practice and an optimal cutoff value for guiding timely preemptive therapy should be clinically validated in future studies.

Comparison of quantitative cytomegalovirus real-time PCR in whole blood and pp65 antigenemia assay: clinical utility of CMV real-time PCR in hematopoietic stem cell transplant recipients

Successful preemptive therapy for cytomegalovirus (CMV) infection in transplant patients depends on the availability of sensitive, specific, and timely diagnostic tests for CMV infection. Although the pp65 antigenemia assay has been widely used for this purpose, real-time quantification of CMV DNA has recently been recognized as an alternative diagnostic approach. However, the guidelines for antiviral therapy based on real-time quantitative polymerase chain reaction (RQ-PCR) have yet to be established. From November 2004 to March 2005, a total of 555 whole blood samples from 131 hematopoietic stem cell transplant (HSCT) recipients were prospectively collected. RQ-PCR was conducted using an Artus CMV LC PCR kit (QIAGEN). Both qualitative and quantitative correlations were drawn between the two methods. Exposure to the antiviral agent influenced the results of the two assays. Additionally, the discrepancy was observed at low levels of antigenemia and CMV DNA load. Via ROC curve analysis, the tentative cutoff value for preemptive therapy was determined to be approximately 2x10(4) copies/mL (sensitivity, 80.0%; specificity, 50.0%) in the high risk patients, and approximately 3x10(4) copies/mL (sensitivity, 90.0%; specificity, 70.0%) in the patients at low risk for CMV disease. Further study to validate the optimal cutoff value for the initiation of preemptive therapy is currently underway.

Comparative evaluation of published cytomegalovirus primers for rapid real-time PCR: which are the most sensitive?

Standardization of human cytomegalovirus (CMV) PCR is highly recommended. As primer design is essential for PCR sensitivity, this study evaluated all published CMV primer pairs to identify the most sensitive for single-round real-time PCR. PubMed (1993-2004) was searched for original papers aimed at CMV PCR. Fifty-seven papers were identified revealing 82 different primer pairs. Of these, 17 primer sets were selected for empirical study, as they were either used in real-time PCR or were evaluated comparatively by conventional PCR. After optimizing the PCR conditions, these primer sets were evaluated by real-time PCR using a SYBR Green format. Analytical sensitivities were assessed by testing the reference standard CMV strain AD169. A blast search was performed to identify mismatches with published sequences. Additionally, 60 clinical samples were tested with the three primer sets showing highest analytical sensitivity and the best match to all CMV strains. Three primer sets located in the glycoprotein B (UL55) gene region were found to be the most sensitive using strain AD169. However, two of these showed a considerable number of mismatches with clinical isolates in a blast search. Instead, two other pairs from the lower matrix phosphoprotein (UL83) gene and DNA polymerase (UL54) gene showed reasonable sensitivity and no mismatches with clinical isolates. These three pairs were further tested with clinical samples, which indicated that the two primer sets from UL55 and UL54 were the most sensitive. Interestingly, the analytical sensitivity of the PCR was inversely correlated with the size of the PCR product. In conclusion, these two primer pairs are recommended for a standardized, highly sensitive, real-time PCR.

Detection of cytomegalovirus in whole blood using three different real-time PCR chemistries

Several different primer-probe chemistries have been produced commercially for real-time PCR detection and quantification of cytomegalovirus, but there are few studies evaluating their relative performance. We assessed three such commercial reagents with respect to analytical and clinical operating characteristics. The samples included 149 clinical whole blood specimens that were de-identified and assayed in parallel with all primer-probe systems. Individual methods used TaqMan, dual fluorescence resonance energy transfer hybridization probes, and labeled primer chemistries. Method comparability was determined both qualitatively, based on pair-wise assessment of concordance, and quantitatively, based on pair-wise linear regression analysis. Analytical sensitivity and the lower end of the linear dynamic range reached 10 target copies per reaction for the TaqMan and labeled primer systems and 100 target copies per reaction for the dual fluorescence resonance energy transfer probe system. Quantitative linearity reached an upper limit of 10(5) copies per reaction for all methods. No assay cross-reactivity was seen with other common viral pathogens (100% analytical specificity). Pair-wise analysis of qualitative results from clinical samples showed no significant differences in sensitivity between the three sets of reagents, and linear regression analysis indicated that the quantitative values achieved were comparable in all positive specimens. The findings demonstrate that similar analytical and clinical performance characteristics can be demonstrated for quantitative detection of cytomegalovirus in clinical whole blood extracts using a wide variety of real-time PCR chemistries.

Epstein-Barr virus load in cerebrospinal fluid of patients with chronic active Epstein-Barr virus infection

Chronic active Epstein-Barr virus (EBV) infection is a rare chronic mononucleosis syndrome involving clonally proliferating EBV-infected T-/NK-cells. EBV DNA was quantified in nonpleocytotic cerebrospinal fluid (CSF) of 9 patients. Three patients with neurologic and/or neuroimaging abnormalities showed high CSF copy numbers. In 1 patient, CSF copy number exceeded the peripheral blood value. CSF EBV-load may predict the central nervous system involvement of EBVT-/NK-cells.

Quantification of DNA in plasma by an automated real-time PCR assay (cytomegalovirus PCR kit) for surveillance of active cytomegalovirus infection and guidance of preemptive therapy for allogeneic hematopoietic stem cell transplant recipients

The performance of a plasma real-time PCR (cytomegalovirus [CMV] PCR kit; Abbott Diagnostics) was compared with that of the antigenemia assay for the surveillance of active CMV infection in 42 allogeneic hematopoietic stem cell transplantation (Allo-SCT) recipients. A total of 1,156 samples were analyzed by the two assays. Concordance between the two assays was 82.2%. Plasma DNA levels correlated with the number of pp65-positive cells, particularly prior to the initiation of preemptive therapy. Fifty-seven episodes of active CMV infection were detected in 37 patients: 18 were defined solely by the PCR assay and four were defined on the basis of the antigenemia assay. Either a cutoff of 288 CMV DNA copies/ml or a 2.42-log(10) increase of DNAemia levels between two consecutive PCR positive samples was an optimal value to discriminate between patients requiring preemptive therapy and those not requiring therapy on the basis of the antigenemia results. The real-time PCR assay allowed an earlier diagnosis of active CMV infection and was a more reliable marker of successful clearance of CMV from the blood. Analysis of the kinetics of DNAemia levels at a median of 7 days posttreatment allowed the prediction of the response to CMV therapy. Two patients developed CMV colitis. The PCR assay tested positive both before the onset of symptoms and during the disease period. The plasma real-time PCR from Abbott is more suitable than the antigenemia assay for monitoring active CMV infection in Allo-SCT recipients and may be used for guiding preemptive therapy in this clinical setting.

Medical history and progress in infectious diseases, especially systemic fungal infections in Japan

This paper reports on medical history from the end of the Edo period to the present and development of studies on infectious diseases, especially medical mycology including systemic fungal diseases. With the inflow of Dutch studies at the end of the Edo period and the adoption of European, mainly German, medicine in the Meiji Restoration, Japanese medical studies gradually developed. However, evolution in the medical field as well as other scientific fields was prevented during the 2nd World War. After the War, there was marked progress in scientific fields and medical research made strong advances. In the past 20 years, basic fungal studies and clinical fungal diseases, especially clinical analysis, clinical diagnosis and treatment of systemic fungal infections have progressed. The level in this field is now equivalent to or higher than that in European countries. Further development is necessary, however, to relieve patients suffering from systemic fungal infections. Members of the Japanese Association of Medical Mycology must be leaders among international medical mycologists.

Prediction of cytomegalovirus (CMV) plasma load from evaluation of CMV whole-blood load in samples from renal transplant recipients

In a prospective cohort of 82 renal transplant recipients, we evaluated the capacity of the cytomegalovirus (CMV) load in whole blood (WB) to predict the plasma CMV load, aiming to identify active CMV infections by using WB samples only and to deduce a WB threshold. Using quantitative real-time PCR, a total of 1,474 WB samples were assayed, of which 279 were positive for CMV, and 140 out of the 276 paired plasma samples tested positive. Thirty (36.6%) patients presented with at least one positive plasma PCR result, and 21 infection episodes (19 patients) required curative treatment (median follow-up time, 12 months). When the plasma CMV load was >500 copies/ml (n = 70), more than 94% (95% confidence interval, 86.0%, 98.4%) of WB samples had >500 copies/ml. Two prediction models were built: log(10) plasma viral load (VL) was calculated as -0.3777 + 0.9342 x log(10) WB VL and as -0.3777 + 0.8563 x log(10) WB VL for patients with and without treatment, respectively. In the validation sample (578 routine samples), 77.2% of the observed and expected plasma viral loads were concordant (95% confidence intervals, 73.5 and 80.5%). According to the model, the plasma viral load was >500 copies/ml when the WB load was >3,170 or >4,000 copies/ml in patients with or without treatment, respectively. WB seems to be an appropriate candidate for routine CMV monitoring of transplant recipients by using a single assay.

Usefulness of quantitative real-time PCR assay for early detection of cytomegalovirus infection in patients with ulcerative colitis refractory to immunosuppressive therapies

BACKGROUND

Studies suggest that cytomegalovirus (CMV) infection exacerbates ulcerative colitis (UC) refractory to immunosuppressive therapies. Early and accurate diagnosis of CMV infection is important for the treatment of UC. We evaluated the usefulness of quantitative real-time polymerase chain reaction (PCR) for detecting CMV infection in inflamed colonic mucosa of patients with UC refractory to immunosuppressive therapies.

METHODS

From 2003 to 2006, 30 patients (mean age: 41 +/- 18 years; 14 men, 16 women) with UC refractory to immunosuppressive therapies were enrolled in the study. We evaluated CMV infection by CMV antigenemia, histologic examination, and quantitative real-time PCR for CMV using colonic mucosa and investigated the clinical outcomes of antiviral therapy.

RESULTS

CMV-DNA was detected only in the inflamed colonic mucosa in 17 (56.7%) of 30 patients. Of the 17 CMV-DNA-positive patients, 4 were positive for CMV antigenemia or inclusion bodies on histologic examination; of the 13 CMV-DNA-negative patients none was positive for CMV antigenemia or inclusion bodies. Of the 17 CMV-DNA-positive patients, 12 (70.6%) were treated with ganciclovir for 2 weeks and 10 patients went into remission. Two other patients required colectomy after antiviral therapy. In contrast, of the 13 CMV-DNA-negative patients 12 (92.3%) achieved remission after intensifying their immunosuppressive therapies.

CONCLUSIONS

Quantitative real-time PCR assay for detecting CMV-DNA is useful for early, accurate diagnosis of CMV infection in patients with UC refractory to immunosuppressive therapies, enabling prompt and appropriate treatment.

Multicentric evaluation of a new commercial cytomegalovirus real-time PCR quantitation assay

Automated real-time PCR systems have become the most common method in the quantitation of viral load during cytomegalovirus (CMV) infection in immuno-compromised patients. In order to evaluate a new commercially available CMV real-time PCR assay (CMV R-gene, Argene, France), a pp65 antigenemia assay and four different "in-house" real-time PCR assays were compared to the CMV R-gene for the detection and the quantitation of CMV load in 506 specimens of whole blood from transplant patients in four French hospital laboratories. The CMV R-gene was more sensitive than the pp65 antigenemia: there were 18% antigenemia-negative versus CMV R-gene-positive samples. A significant correlation was found between DNA quantitation by CMV R-gene and the number of positive cells detected by the pp65 antigenemia test (Spearman's rank test, r=0.63, p<0.0001). A CMV DNA load equivalent to 50 pp65-positive cells/200000 polymorphonuclear leukocytes was 5.26log(10)copies/mL of whole blood. When the CMV R-gene kit was compared to the four other "in-house" real-time PCR assays, there were few discordant results (6.7% total for the four laboratories), all detected with a weak positive CMV DNA viral load. Spearman's coefficients showed a good (r=0.82 for laboratory 1, r=0.66 for laboratory 3) to excellent (r=0.99 for laboratory 2, r=0.94 for laboratory 4) correlation between CMV R-gene and the four real-time "in-house" PCR assays. However, the results of CMV DNA viral load generated by CMV R-gene test were constantly higher than those generated by three out of four "in-house" PCR assays. This mean variation in CMV DNA viral load measured by CMV R-gene and "in-house" PCRs was of 0.77log(10), 0.04log(10), 0.77log(10) and 0.97log(10), for laboratories 1, 2, 3 and 4, respectively. We concluded that there was variability between results of different real-time PCR assays for CMV DNA quantitation. This observation emphasized the need of a standardised commercial assay to allow an "inter-laboratory" comparison of results. Our study showed that CMV R-gene is an accurate, efficient, reliable and versatile tool for rapid diagnosis and monitoring of CMV disease in transplantation recipients.