Qualitative and semiquantitative polymerase chain reaction testing for cytomegalovirus DNA in serum allows prediction of CMV related disease in liver transplant recipients.
(9/5460)
AIM: To identify cytomegalovirus (CMV) infection in liver transplant recipients by polymerase chain reaction (PCR) techniques and to separate the cases in which CMV related disease will occur, for whom treatment is indicated, from those in whom infection will remain innocuous. METHODS: The combination of qualitative and semiquantitative PCR of serum and urine was assessed to determine whether these assays can identify those at risk of CMV related disease and compared their performance with conventional approaches to diagnosis. RESULTS: Qualitative PCR of serum had superior specificity, sensitivity, and positive and negative predictive values compared with urine DEAFF (detection of early antigen fluorescent foci) and PCR of urine. All episodes of CMV related disease were associated with the presence of CMV DNA by PCR in serum or urine; CMV was detected before clinical onset in 70% and 60% of cases, respectively. The period over which CMV DNA could be detected was not correlated with CMV related disease. Both peak viral load and cumulative viral load estimated using a semiquantitative PCR method on serum samples positive by the qualitative method could be used to distinguish asymptomatic infection from CMV related disease with 100% specificity and sensitivity. In contrast semiquantitative PCR of urine was of little value. CONCLUSIONS: An approach based on PCR testing with a combination of qualitative and subsequently semiquantitative serum samples would improve the diagnosis of CMV infection and aid identification of those patients at risk of CMV related disease, allowing treatment to be targeted specifically. (+info)
High seroprevalence of antibodies to human herpesvirus-8 in Egyptian children: evidence of nonsexual transmission.
(10/5460)
BACKGROUND: In western countries, human herpesvirus-8 (HHV-8) appears to be transmitted mainly by sexual contact. To evaluate the role of other transmission routes, especially in developing countries, we estimated the seroprevalence of HHV-8 in Egyptian children, who, if seropositive, would have acquired the virus through a nonsexual route. METHODS: Sera from 196 children (<1-12 years of age), 20 adolescents (13-20 years of age), and 30 young adults (21-25 years of age) attending a vaccination program in Alexandria, Egypt, were studied. Immunofluorescence assays were used to detect antibodies against HHV-8 lytic-phase antigens (anti-lytic) and latent-phase antigens (anti-latent). Antibodies against Epstein-Barr virus viral cap antigen, cytomegalovirus, and HHV-6 were detected by enzyme-linked immunosorbent assays. Seroprevalence of these herpesviruses was calculated after stratifying the subjects by age. RESULTS: Anti-lytic and anti-latent HHV-8 antibodies were detected in 44.7% and 8.5% of the study participants, respectively. The prevalence of anti-lytic antibodies tended to increase with age, exceeding 50% in children older than 6 years; once children reached the age of 10 years, the prevalence tended to stabilize. The seroprevalence of other herpesviruses tended to be higher than that of HHV-8, ranging from approximately 83% to more than 97% in the 9- to 12-year age group. One- to 3-year-old children had higher titers of antilytic HHV-8 antibodies than children in the other age groups. Anti-latent antibodies were more frequently detected in individuals with high anti-lytic antibody titers. CONCLUSIONS: HHV-8 antibodies are highly prevalent in Egyptian children, suggesting that, in developing countries, HHV-8 infection may be acquired early in life through routes other than sexual transmission. The lower seroprevalence of HHV-8 relative to that of the other herpesviruses suggests that HHV-8 is less transmissible than other common herpesviruses. (+info)
The R27080 glycoprotein is abundantly secreted from human cytomegalovirus-infected fibroblasts.
(11/5460)
A 45 kDa glycoprotein was purified from the culture media of human cytomegalovirus (HCMV)-infected fibroblasts. N-terminal sequencing revealed that the protein, R27080, is the translation product of the R27080 open reading frame of HCMV. R27080 is highly glycosylated and contains no cysteine or methionine residues. Proteolytic cleavage of R27080 by a furin-like enzyme was analysed in transfected COS-7 cells. R27080 is the first identified viral protein secreted from HCMV-infected cells. (+info)
Effects of human cytomegalovirus major immediate-early proteins in controlling the cell cycle and inhibiting apoptosis: studies with ts13 cells.
(12/5460)
The major immediate-early (MIE) gene of human cytomegalovirus (HCMV) encodes several MIE proteins (MIEPs) produced as a result of alternative splicing and polyadenylation of the primary transcript. Previously we demonstrated that the HCMV MIEPs expressed from the entire MIE gene could rescue the temperature-sensitive (ts) transcriptional defect in the ts13 cell line. This defect is caused by a ts mutation in TAFII250, the 250-kDa TATA binding protein-associated factor (TAF). These and other data suggested that the MIEPs perform a TAF-like function in complex with the basal transcription factor TFIID. In addition to the transcriptional defect, the ts mutation in ts13 cells results in a defect in cell cycle progression which ultimately leads to apoptosis. Since all of these defects can be rescued by wild-type TAFII250, we asked whether the MIEPs could rescue the cell cycle defect and/or affect the progression to apoptosis. We have found that the MIEPs, expressed from the entire MIE gene, do not rescue the cell cycle block in ts13 cells grown at the nonpermissive temperature. However, despite the maintenance of the cell cycle block, the ts13 cells which express the MIEPs are resistant to apoptosis. MIEP mutants, which have previously been shown to be defective in rescuing the ts transcriptional defect, maintained the ability to inhibit apoptosis. Hence, the MIEP functions which affect transcription appear to be separable from the functions which inhibit apoptosis. We discuss these data in the light of the HCMV life cycle and the possibility that the MIEPs promote cellular transformation by a "hit-and-run" mechanism. (+info)
Clinical significance of expression of human cytomegalovirus pp67 late transcript in heart, lung, and bone marrow transplant recipients as determined by nucleic acid sequence-based amplification.
(13/5460)
Human cytomegalovirus (HCMV) infection was monitored retrospectively by qualitative determination of pp67 mRNA (a late viral transcript) by nucleic acid sequence-based amplification (NASBA) in a series of 50 transplant recipients, including 26 solid-organ (11 heart and 15 lung) transplant recipients (SOTRs) and 24 bone marrow transplant recipients (BMTRs). NASBA results were compared with those obtained by prospective quantitation of HCMV viremia and antigenemia and retrospective quantitation of DNA in leukocytes (leukoDNAemia). On the whole, 29 patients were NASBA positive, whereas 10 were NASBA negative, and the blood of 11 patients remained HCMV negative. NASBA detected HCMV infection before quantitation of viremia did but after quantitation of leukoDNAemia and antigenemia did. In NASBA-positive blood samples, median levels of viremia, antigenemia, and leukoDNAemia were significantly higher than the relevant levels detected in NASBA-negative HCMV-positive blood samples. By using the quantitation of leukoDNAemia as the "gold standard," the analytical sensitivity (47.3%), as well as the negative predictive value (68. 3%), of NASBA for the diagnosis of HCMV infection intermediate between that of antigenemia quantitation (analytical sensitivity, 72. 3%) and that of viremia quantitation (analytical sensitivity, 28.7%), while the specificity and the positive predictive value were high (90 to 100%). However, with respect to the clinically relevant antigenemia cutoff of >/=100 used in this study for the initiation of preemptive therapy in SOTRs with reactivated HCMV infection, the clinical sensitivity of NASBA reached 100%, with a specificity of 68. 9%. Upon the initiation of antigenemia quantitation-guided treatment, the actual median antigenemia level was 158 (range, 124 to 580) in SOTRs who had reactivated infection and who presented with NASBA positivity 3.5 +/- 2.6 days in advance and 13.5 (range, 1 to 270) in the group that included BMTRs and SOTRs who had primary infection (in whom treatment was initiated upon the first confirmation of detection of HCMV in blood) and who presented with NASBA positivity 2.0 +/- 5.1 days later. Following antiviral treatment, the durations of the presence of antigenemia and pp67 mRNA in blood were found to be similar. In conclusion, monitoring of the expression of HCMV pp67 mRNA appears to be a promising, well-standardized tool for determination of the need for the initiation and termination of preemptive therapy. Its overall clinical impact should be analyzed in future prospective studies. (+info)
Amplification of the six major human herpesviruses from cerebrospinal fluid by a single PCR.
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We used a novel type of primer system, a system that uses stair primers, in which the primer sequences are based on consensus sequences in the DNA polymerase gene of herpesvirus to detect herpesviruses by PCR. A single PCR in a single tube detected the six major herpesviruses that infect the central nervous system: herpes simplex virus type 1 (HSV-1), and type 2 (HSV-2), cytomegalovirus (CMV), Epstein-Barr virus (EBV), varicella-zoster virus (VZV), and human herpesvirus 6 (HHV-6). We used the technique to analyze 142 cerebrospinal fluid (CSF) samples that had been stored at -80 degrees C and compared the results with those obtained previously for the same samples by standard, targeted PCR. Four hundred one targeted PCR tests had been run with the 142 samples to detect HSV-1, HSV-2, CMV, and VZV; screening for EBV and HHV-6 was not prescribed when the samples were initially taken. Eighteen CSF samples tested positive by classic targeted PCR. The herpesvirus consensus PCR detected herpesviruses in 37 samples, including 3 samples with coinfections and 17 viral isolates which were not targeted. Two samples identified as infected by the targeted PCR tested negative by the consensus PCR, and eight samples that tested positive by the consensus PCR were negative by the targeted PCR. One hundred three samples scored negative by both the targeted and the consensus PCRs. This preliminary study demonstrates the value of testing for six different herpesviruses simultaneously by a sensitive and straightforward technique rather than screening only for those viruses that are causing infections as suggested by clinical signs. (+info)
Multicenter comparison of the digene hybrid capture CMV DNA assay (version 2.0), the pp65 antigenemia assay, and cell culture for detection of cytomegalovirus viremia.
(15/5460)
We compared the Digene Hybrid Capture CMV DNA Assay version 2.0, the pp65 antigenemia assay, traditional tube culture, and shell vial culture for the detection of cytomegalovirus (CMV) viremia in several patient populations at three centers. Of 561 blood specimens collected from 402 patients, complete clinical and laboratory data were available for 489. Using consensus definitions for true positives and true negatives, the sensitivities of the Hybrid Capture assay, antigenemia, shell vial, and tube culture were 95, 94, 43, and 46%, respectively. The specificities of the Hybrid Capture assay and antigenemia were 95 and 94%, respectively. At all three study sites, the detected level of CMV viremia was significantly higher with the Hybrid Capture assay or antigenemia than with shell vial and tube culture. In a group of 131 healthy nonimmunosuppressed volunteers, the Hybrid Capture assay demonstrated a specificity of over 99%. The Hybrid Capture assay is a standardized assay that is simple to perform and can utilize whole blood specimens that have been stored for up to 48 h. The high sensitivity and specificity of the Hybrid Capture assay along with its simplicity and flexibility make it a clinically useful assay for the detection of CMV viremia in immunocompromised or immunosuppressed patients. Further evaluation to determine its role in predicting CMV disease and for monitoring the therapeutic response to anti-CMV therapy is needed. (+info)
Prior cytomegalovirus infection and the risk of restenosis after percutaneous transluminal coronary balloon angioplasty.
(16/5460)
BACKGROUND: Restenosis is a common problem after all revascularization procedures in atherosclerotic coronary arteries. Reactivated human cytomegalovirus (CMV) has been detected in tissues of restenotic vascular lesions and was hypothesized to be a contributing pathogenic factor. Recent data suggest an association of restenosis after optimal coronary atherectomy with CMV serostatus, and a possible role of antiviral therapy was discussed. We therefore tested the hypothesis that prior CMV infection might be a risk factor for restenosis after conventional coronary balloon angioplasty (PTCA). METHODS AND RESULTS: We analyzed 92 consecutive patients who had been admitted for control angiography after previous PTCA within a mean interval of 6 months. Anti-CMV antibodies were measured as an indicator of prior CMV infection and latency. The coronary angiograms before PTCA, directly after, and 6 months later were analyzed quantitatively. Sixty-five percent of the patients were CMV-positive. Before PTCA, the degree (mean+/-SD) of stenosis was 69+/-10% in CMV-positive and 68+/-8.3% in CMV-negative subjects. PTCA resulted in a residual stenosis of 39% in both groups. After 6 months, the late losses of luminal diameter in the CMV-positive and -negative groups were 11+/-13% and 12+/-15%, respectively (P=0.658). In an ANCOVA with 25 potential risk factors for restenosis, CMV serostatus was not significantly associated with restenosis development. CONCLUSIONS: Our data indicate that prior CMV infection, in contrast to optimal atherectomy, is not associated with chronic restenosis after conventional coronary balloon angioplasty. The results do not support a possible benefit from antiviral therapy. (+info)