Jennie Wilson

Cytomegalovirus (CMV) DNA load predicts relapsing CMV infection after solid organ transplantation

Cytomegalovirus (CMV) DNA load was analyzed as a marker for relapse of CMV infection in 24 solid organ transplant patients with CMV infection or disease who received a fixed 14-day course of intravenous ganciclovir. Viral load was measured in blood samples obtained before and at the completion of treatment. Eight (33%) of 24 patients developed relapsing CMV infection. Median pretreatment viral loads were higher in the relapsing group (80,150 copies/106 leukocytes) than in the nonrelapsing group (5500 copies/106 leukocytes; P=.007). The relapsing group also had persistent detectable viral DNA (median, 5810 copies/106 leukocytes) after treatment, whereas it was undetectable in the nonrelapsing group (P<. 0001). Primary CMV infection (seronegative recipients of seropositive organs, D+R-) was an independent marker for CMV relapse (P=.03), and these patients had higher pre- and posttreatment viral loads than did non-D+/R- patients (P<.0001 and P=.0014, respectively). CMV DNA load is a useful marker for individualizing antiviral treatment of CMV infection in solid organ transplant recipients.

Allograft Rejection Predicts the Occurrence of Late-Onset Cytomegalovirus (CMV) Disease among CMV-Mismatched Solid Organ Transplant Patients Receiving Prophylaxis with Oral Ganciclovir

The natural history of cytomegalovirus (CMV) disease associated with solid organ transplantation has been modified as a result of the widespread use of antiviral prophylaxis. Anecdotal reports have indicated a reduction of CMV disease at the expense of its later occurrence after completion of ganciclovir prophylaxis. The present study investigated the occurrence of CMV disease and its risk factors among 37 liver and kidney transplant recipients with CMV D+/R- status who received oral ganciclovir during the first 100 days posttransplantation. CMV disease occurred in 9 patients (24.3%) at a median of 144 days posttransplantation (range, 95-190 days). Allograft rejection was found to be strongly associated with the occurrence of late-onset CMV disease (risk ratio, 6.6; 95% confidence interval, 1.4-32.1; P=.02). Thus, CMV D+/R- solid organ transplant recipients receiving 3 months of oral ganciclovir who develop allograft rejection during the period of antiviral prophylaxis may benefit from extended and/or enhanced antiviral prophylaxis to prevent late-onset CMV disease.

Human β-Herpesvirus Interactions in Solid Organ Transplant Recipients

The replication of beta-herpesviruses-cytomegalovirus (CMV), human herpesvirus (HHV)-6, and HHV-7-and their association with CMV disease and response to antiviral therapy were prospectively investigated in 33 liver transplant recipients not given antiviral prophylaxis. CMV, HHV-6, and HHV-7 DNA were detected within 8 weeks after transplantation in 70%, 33%, and 42% of the patients, respectively. The univariate association between CMV disease and the 3 beta-herpesviruses was more significant by virus load quantitation than by qualitative detection of DNA. This association with high levels of CMV, HHV-6, and HHV-7 (P<.001,.022, and.001, respectively) occurred mainly in CMV-seronegative recipients of transplants from CMV-seropositive donors. Antiviral therapy with ganciclovir (Gcv) reduced the load of CMV and HHV-6 and HHV-7. These results suggest that CMV disease in transplant recipients is related to the unique interaction of the 3 beta-herpesviruses and is ultimately reduced after intravenous Gcv treatment.

The clinical use of various blood compartments for cytomegalovirus (CMV) DNA quantitation in transplant recipients with CMV disease.

BACKGROUND The quantitation of cytomegalovirus (CMV) DNA is a cornerstone in the management of CMV disease in transplant recipients. However, a consensus as to what is the optimal blood compartment for the detection and quantitation of CMV DNA in peripheral blood is nonexistent. METHODS With an automated quantitative assay, we have simultaneously quantified the CMV DNA load in whole blood (WB), plasma (PL), peripheral blood leukocytes (PBL), and peripheral blood mononuclear cells (PBMC) in 319 samples from 17 transplant recipients with 19 episodes of CMV disease that were treated with 2 weeks of intravenous ganciclovir. RESULTS Higher levels of CMV DNA were observed in WB than PL (PL minus WB mean difference, 0.67 log; 95% confidence interval, -1.02 to -0.32; P=0.0009). This observation was most evident before treatment with intravenous ganciclovir (pretreatment geometric mean CMV DNA was 45,412 copies per ml of WB vs. 14,995 copies per ml of PL). In contrast, the CMV DNA levels between PBL and PBMC were highly comparable throughout the course of CMV disease and its treatment. Intravenous ganciclovir exerted a uniform effect on the four blood compartments with no statistically significant difference in the degree and rate of CMV DNA decline between WB and PL and between PBL and PBMC. CONCLUSIONS Although our study demonstrates the adequacy of all blood compartments for CMV DNA quantification, the higher sensitivity of WB and its yield of higher CMV DNA render it an optimal sample for monitoring CMV DNA load during CMV disease in immunocompromised patients.

Selective Reactivation of Human Herpesvirus 6 Variant A Occurs in Critically Ill Immunocompetent Hosts

Reactivation of human beta-herpesviruses (cytomegalovirus [CMV], human herpesvirus [HHV]-6, and HHV-7) in nonimmunocompromised hosts is rare. Because these viruses are susceptible to reactivation by cytokines and stress-related mechanisms, the incidence of their reactivation was investigated among 120 patients during stress related to critical illness and compared with findings among 50 healthy volunteers. Human beta-herpesvirus DNA was found in 65% of critically ill patients (60% men; mean age, 63 years) who required admission to an intensive care unit for medical (40%) or surgical (53%) indications or trauma (7%). HHV-6 reactivation was higher in critically ill patients than in healthy volunteers (54/101 vs. 0/50; P=.001). All patients except 1 were confirmed as HHV-6 variant A (mean virus load, 5066 copies/10(6) peripheral blood leukocytes). The reactivation of HHV-6A did not affect disease severity and outcome. No significant reactivation of HHV-7 or CMV was demonstrated among the critically ill patients. These findings contribute to the less-defined epidemiology of HHV-6A infection.

Preemptive Use of Oral Ganciclovir to Prevent Cytomegalovirus Infection in Liver Transplant Patients: A Randomized, Placebo-Controlled Trial

The use of postdetection antiviral treatment of cytomegalovirus (CMV) as a strategy to prevent infection and disease in solid-organ transplant patients has not been evaluated by placebo-controlled trials. We carried out such a study in 69 patients who had received liver transplants and had positive results of CMV polymerase chain reaction within 8 weeks after transplantation but did not have concomitant CMV infection or disease. These patients were randomly assigned to receive placebo or oral ganciclovir for 8 weeks. CMV infection developed in 21% and disease developed in 12% of placebo recipients (P =.022), compared with 3% and 0%, respectively, among ganciclovir recipients (P =.003). Similarly, in the placebo arm, 55% and 36% of CMV-negative patients who received organs from CMV-positive donors developed CMV infection or disease, respectively (P =.02), compared with 11% and 0% of such patients in the ganciclovir arm (P <.01). Oral ganciclovir administered on CMV detection by PCR prevents CMV infection or disease after liver transplantation.

The pathogenesis of hepatitis C virus is influenced by cytomegalovirus

We investigated the effect of beta-herpesviruses on allograft failure and mortality, hepatitis C virus (HCV) replication, and liver histologic characteristics among 92 HCV-infected liver transplant recipients. Reactivation of cytomegalovirus (CMV) but not of human herpesvirus 6 (HHV-6) was independently associated with allograft failure and mortality (risk ratio, 3.71; 95% confidence interval, 1.64-8.39); allograft failure and mortality was observed in 48% of patients with CMV disease, 35% of patients with subclinical CMV infection, and 17% of patients without CMV infection (P=.0275). CMV reactivation was highly predictive of mortality (P<.001), regardless of whether it remained subclinical or evolved into CMV disease. Patients with CMV disease had a higher fibrosis stage (P=.05) and had a trend toward a higher hepatitis activity index (P=.10) and HCV load (P=.10) at 16 weeks after liver transplantation. The pathogenesis of HCV is influenced by its interaction with CMV but not with HHV-6.

Comparative Quantitation of Cytomegalovirus (CMV) DNA in Solid Organ Transplant Recipients with CMV Infection by Using Two High-Throughput Automated Systems

ABSTRACT Cytomegalovirus (CMV) DNA quantitation in clinical specimens is progressively becoming a cornerstone in the diagnosis and management of CMV infection in the immunocompromised host. We evaluated two automated and reproducible PCR tests, the LightCycler (Roche Molecular Biochemicals, Indianapolis, Ind.) and the COBAS AMPLICOR CMV Monitor (Roche Diagnostics, Pleasanton, Calif.), for the detection of CMV DNA in blood samples from transplant recipients with CMV infection as determined by shell vial culture. Following a log transformation analysis, the mean CMV DNA in plasma (PL), whole blood (WB), peripheral blood leukocytes (PBL), and peripheral blood mononuclear cells (PBMC) using the LightCycler was 6.79 copies per ml, 7.23 copies per ml, 6.38 copies per 2 × 106 cells, and 6.27 copies per 2 × 106 cells, respectively. This compares to 7.86 copies per ml, 8.37 copies per ml, 7.59 copies per 2 × 106cells, and 7.44 copies per 2 × 106 cells, respectively, using COBAS AMPLICOR CMV Monitor. While higher CMV DNA levels were observed for the various blood compartments analyzed using COBAS AMPLICOR CMV Monitor, a high degree of correlation was evident between the two automated systems (jackknife correlation r= PL 0.77 [95% confidence interval (CI); 0.64, 0.90], WB 0.77 [95% CI; 0.62, 0.92], PBL 0.77 [95% CI; 0.67, 0.88], and PBMC 0.81 [95% CI; 0.72, 0.89], all P < 0.001). Therefore, we conclude that either automated diagnostic system is accurate for CMV DNA quantitation.

Detection of simultaneous β‐herpesvirus infections in clinical syndromes due to defined cytomegalovirus infection

Abstract: Human herpesvirus (HHV)‐6 and HHV‐7 are increasingly being recognized as emerging pathogens among transplant recipients. Using quantitative polymerase chain reaction assays, we demonstrate the presence of HHV‐6 and/or HHV‐7 in 18 of 20 episodes of clinically presumed or microbiologically confirmed cytomegalovirus (CMV) infection. Seventeen (89%) of 19 microbiologically confirmed cytomegalovirus (CMV)‐infected patients had concomitant HHV‐6 variant B (47%) and/or HHV‐7 (63%) infection. The degree of HHV‐6 coinfection was significantly correlated with hyperbilirubinemia while HHV‐7 coinfection demonstrated a non‐significant trend toward cytopenias. In one of the 20 episodes described herein, the ‘viral syndrome’ was due solely to HHV‐7 infection; clinical and virological response was observed during intravenous ganciclovir therapy in this patient. While this study emphasizes the significance of HHV‐6 and/or HHV‐7 coinfection during episodes of CMV infection, it significantly highlights the novel observation of the causal role of HHV‐7 (in the absence of HHV‐6 and CMV) in a clinical illness presumed to be caused CMV. Thus, HHV‐7 (and HHV‐6) should be considered as a pathogen (or copathogen) in the viral syndromes following organ transplantation.

CLINICAL SIGNIFICANCE OF VIRAL LOAD IN THE DIAGNOSIS OF CYTOMEGALOVIRUS DISEASE AFTER LIVER TRANSPLANTATION

In a cohort of 43 liver transplant recipients who did not receive antiviral prophylaxis, qualitative and quantitative polymerase chain reactions (PCRs) from peripheral blood were prospectively compared to determine their value in the diagnosis of established cytomegalovirus (CMV) disease and for the early detection of CMV replication as a marker for preemptive antiviral therapy. Using a cutoff of 7000 copies of CMV DNA per sample, the specificity and positive predictive values of qualitative PCR for the diagnosis of established CMV disease increased from 33% to 89% and from 54% to 82%, respectively, without reducing the 100% sensitivity and negative predictive value. By contrast, quantification of viral load provided no additional advantage to qualitative PCR for the early diagnosis of CMV infection before development of disease.