Cytomegalovirus Antigenemia Assay Research Articles

Diagnostic yield of the cytomegalovirus (CMV) antigenemia assay and clinical features in solid organ transplant recipients and hematopoietic stem cell transplant recipients with CMV pneumonia

Data are limited on the value of non-invasive diagnostic methods, such as the cytomegalovirus (CMV) antigenemia assay, and the clinical features of CMV pneumonia in patients who have undergone solid organ transplant (SOT) compared with those who have had hematopoietic stem cell transplant (HSCT). All adult patients with suspected CMV pneumonia, who had received SOT or HSCT in a tertiary hospital during a 5-year period, were retrospectively enrolled. CMV pneumonia was defined as clinical and radiographic evidence of pneumonia in association with the isolation of CMV in viral cultures of bronchoalveolar lavage or lung tissue specimens, or with the identification of CMV in lung tissue. In total, 36 patients with CMV pneumonia were identified. Of these, 29 (80%) had received SOT and 7 (20%) had received HSCT. The incidence of CMV pneumonia in the patients with SOT (3.0 per 1000 person-years [95% confidence interval {CI} 0.6-8.7]) was lower than in those with HSCT (17.0 per 1000 person-years [95% CI 9.9-27.2], P=0.003) and CMV-related mortality showed a tendency to have lower mortality in patients with SOT (10% [3/29]) than with HSCT (43% [3/7], P=0.07). The overall sensitivity of the CMV assay (≥1/200,000 leukocytes) in patients with CMV pneumonia was 69% (95% CI 52-84%). The CMV antigenemia test is of limited value in diagnosing CMV pneumonia, given the high cost of false-negative diagnoses of CMV pneumonia.

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.

Diagnostic value of antigenemia assay for cytomegalovirus gastrointestinal disease in immunocompromised patients

To investigate the utility of the cytomegalovirus (CMV) antigenemia assay for the diagnosis of CMV gastrointestinal disease (GID). One hundred and thirty immunocompromised patients were enrolled in this study. Patients with a history of anti-CMV treatment and who had not undergone examination using the antigenemia assay were excluded. CMV-GID was defined as the detection of large cells with intranuclear inclusions alone or associated with granular cytoplasmic inclusions by biopsy. Biopsy sections were stained with hematoxylin and eosin and immunohistochemically stained with anti-CMV. We evaluated the association between CMV-GID and patient characteristics (symptoms, underlying disease, medication, leukocyte counts, and antigenemia assay). All patients were checked with an human immunodeficiency virus (HIV) antibody test before endoscopic examination. White blood cell (WBC) counts were obtained from medical records within 1 wk of endoscopy. Leukopenia was defined as a total WBC count < 5000 cells/mm(3). For HIV patients, we also checked CD4+ counts from medical records. A total of 99 patients were retrospectively selected for analysis. Of the immunocompromised patients, 19 had malignant disease, 18 had autoimmune disease, 19 had disorders of biochemical homeostasis, three had undergone transplantation, and 45 had HIV infection. A total of 50 patients had received immunosuppressive therapy. No patients had inflammatory bowel disease. Fifty-five patients were diagnosed as having CMV-GID. Univariate analysis indicated an association between HIV infection, leukopenia, and positive antigenemia and CMV-GID (P < 0.05). Multivariate analysis using logistic regression revealed that HIV infection and positive antigenemia were the only independent factors related to CMV-GID (P < 0.01). The sensitivity, specificity, positive predictive value, and negative predictive value of antigenemia for CMV-GID were 65.4%, 93.6%, 91.9%, and 71.0%, respectively. In a subgroup analysis, patients with leukopenia displayed low sensitivity and high specificity. Minimal differences in accuracy were seen among patients with or without leukopenia. HIV-infected patients displayed low sensitivity and high specificity. Accuracy barely differed between HIV-positive and -negative patients. In HIV-infected patients, CD4 count < 50 cells/μL resulted in low sensitivity and high specificity. Differences in accuracy among patients were minor, regardless of CD4 count. In patients who had undergone both quantitative real-time polymerase chain reaction (PCR) and antigenemia assay, real-time PCR was slightly more accurate in terms of sensitivity than the antigenemia assay; however, this difference was not statistically significant (P = 0.312). If the antigenemia test is positive, endoscopic lesions are acceptable for the diagnosis of CMV-GID without biopsy. The accuracy is not affected by HIV infection and leukopenia. Either PCR or the antigenemia assay are valid.

Emergence of Cytomegalovirus Disease in Patients Receiving Temozolomide: Report of Two Cases and Literature Review

Temozolomide chemotherapy has become part of the therapy used to treat glioblastoma multiforme and refractory anaplastic astrocytoma. Temozolomide frequently produces profound lymphopenia. We report 2 cases of cytomegalovirus disease that occurred in patients receiving temozolomide therapy and review 4 additional cases reported in the literature. Narrow monitoring with cytomegalovirus antigenemia assay should be considered for recommendation.

Diagnostic Performance of the Cytomegalovirus (CMV) Antigenemia Assay in Patients with CMV Gastrointestinal Disease

Of 149 patients with suspected cytomegalovirus (CMV) gastrointestinal disease, 51 (36%) confirmed cases, 6 (4%) probable cases, and 64 (45%) instances of non-CMV gastrointestinal disease were analyzed using the CMV antigenemia assay; 22 patients (5%) with indeterminate gastrointestinal disease were excluded. The sensitivity and specificity of the CMV antigenemia assay (defined as detection of > or =1 positive cells per 200,000 leukocytes) for diagnosis of CMV gastrointestinal disease were 54% (95% confidence interval, 41%-68%) and 88% (95% confidence interval, 77%-94%), respectively.

Evaluation of an Abbreviated Protocol for Cytomegalovirus pp65 Antigenemia Testing

The cytomegalovirus antigenemia assay remains a useful tool for monitoring reactivation among transplant recipients. In this study, we compared protocols using direct lysis of small-volume, whole blood (WB) samples vs peripheral blood leukocyte (PBL)-enriched fractions. Of 363 evaluable samples, 51 (14.0%) were positive by one or both methods. Sensitivity, specificity, and negative and positive predictive values were similar (76%, 99%, 96%, and 95% vs 71%, 100%, 96%, and 100% for the WB and PBL methods, respectively). Stratification of qualitative results by WBC count revealed comparable detection rates by each method, although the total number of positive results from leukopenic samples was significantly lower than from nonleukopenic samples (P= .04). Correlation between quantitative results was high, yet the degree of clinical agreement was suboptimal. We conclude that the small-volume, WB lysis method yields results statistically comparable to that of a PBL fractionation method but with fewer technical steps and less complexity.

Clinical Usefulness of Human Cytomegalovirus Antigenemia Assay after Kidney Transplantation

Clinical Usefulness of Human Cytomegalovirus Antigenemia Assay after Kidney Transplantation

The Rate of Cytomegalovirus Infection and Disease in Correlation with the Type of Hematopoietic Stem Cell Transplantation in the Era of Preemptive Antiviral Therapy

Background: Despite diagnostic and therapeutic advances, cytomegalovirus (CMV) has remained a significant complication after hematopoietic stem cell transplantation (HSCT). The widespread use of preemptive antiviral therapy has reduced the occurrence of early CMV disease and changed its epidemiology. In order to define the current trends and to establish future guidelines, we retrospectively analyzed the rate of CMV infection and disease in the following types of HSCT:autologous HSCT,fully matched-,mismatched- andhaploidentical-allogeneic HSCT.Patients & Methods: Patients receiving HSCT in the Hadassah Hebrew University Medical Center over a 5-year period (April 2003-March 2008) were retrospectively reviewed for the occurrence of CMV infection and disease in relation to the 4 types of HSCT. Infection was defined by the presence of positive CMV antigenemia and/or real time PCR assays, and patients received preemptive antiviral treatment upon detection of CMV infection.Results: Of 634 patients who received HSCT in our center during the study period, 276 (43.5%) developed CMV infection and 16 (2.5%) had evidence for CMV disease, with the vast majority of disease occurring among haploidentical HSCT recipients. The occurrence of CMV infection and disease by transplant type is presented in the table:Type of HSCTTotal Patients (tested patients)Number of patients with CMV infection (% of tested patients)CMV disease (% of tested patients; % of patients with CMV infection)(A.) autologous HSCT240 (214)55 (25.7%)1 (0.5%; 1.8%)(B.) fully matched289 (254)145 (57.1%)1 (0.4%; 0.7%)(C.) mismatched-44 (38)20 (52.6%)%)0(D.) haploidentical-allogeneic HSCT113 (102)56 (54.9%)14 (13.7%; 25.0%)No statistically significant differences were found between the CMV-donor and recipient serostatus in the 3 categories of allogeneic HSCT. The rate of CMV infection was significantly higher in allogeneic compared to autologous HSCT (p < 0.001), with no significant differences between the 3 types of allogeneic HSCT. However, the rate of disease was significantly higher in haploidentical HSCT (p < 0.001). Fifteen of the 16 patients with CMV disease had a fatal outcome. We are presently analyzing the viral load kinetics and the associated risk factors in the different HSCT categories,Conclusions: Preemptive antiviral approach proved to be effective in the prevention of CMV disease in autologous and fully matched as well as mismatched allogeneic HSCT recipients.The increased rate of CMV disease and associated mortality in recipients of haploidentical HSCT despite preemptive antiviral therapy reflects their delayed immune reconstitution, and raises concern regarding the effectiveness of the current preemptive antiviral approach. Based on our findings, close monitoring and prophylactic antiviral treatment should be employed in this high-risk subgroup of HSCT recipients.

Comparison of a new Light Diagnostics™ and the CMV Brite™ to an in-house developed human cytomegalovirus antigenemia assay

Background Antigenemia, i.e. detection and quantification of human cytomegalovirus (HCMV) peripheral blood pp65-positive leukocytes, is still one of the two major assays available for diagnosis and monitoring of HCMV infections. Objectives To evaluate the performance of a new commercial assay under development (Light Diagnostics™). Study design To compare the performance of the new assay with a commercial assay (CMV Brite™) already available on 300 blood samples from immunocompromised patients using as a reference the original in-house developed assay. Results Although 30 blood samples gave discrepant results among the 3 antigenemia assays, the Light Diagnostics™ detected an overall number of antigenemia-positive blood samples (sensitivity 84%) identical to that detected by CMV Brite™ (sensitivity 88%) and in-house assay (91/300, 30.3%). Problems of non-specific cytoplasmic staining were encountered with the CMV Brite™ assay in 219/300 (73%) blood samples. Conclusions The Light Diagnostics™ assay provides results comparable to those of the reference assay both in terms of specificity and sensitivity (number of pp65-positive leukocytes).

Immunohistochemically proven cytomegalovirus gastrointestinal diseases in three patients with autoimmune diseases

Cytomegalovirus (CMV) disease is a serious infectious complication in compromised hosts. Therefore, there are several studies on the diagnosis and prophylactic/pre-emptive therapy of CMV diseases in patients with solid organ transplants, bone marrow transplants, hematopoietic stem cell transplants, and HIV diseases. However, in patients with autoimmune disease, there are only few studies on the diagnosis and prediction of CMV diseases. In the present article, we described three autoimmune cases that developed CMV gastrointestinal disease because of therapy-related immunosuppression. Although all three patients had a low-level CMV antigenemia without diarrhea or melena, CMV was detected in the gastrointestinal tract tissue. We concluded that CMV-antigenemia assay has a limited value in the diagnosis and prediction of CMV gastrointestinal disease in patients with autoimmune diseases, and that immunohistochemical confirmation of CMV tissue involvement should be recommended especially when the typical clinical gastrointestinal manifestations are lacking.

Is Combined Pretransplantation Seropositivity of Kidney Transplant Recipients for Cytomegalovirus Antigens (pp150 and pp28) a Predictor for Protection against Infection?

Objective: This study was aimed at detecting antibodies to the antigens which may contribute to protection against cytomegalovirus (CMV) infection after organ transplantation. Materials and Methods: A total of 203 kidney transplant patients were enrolled in the study. Based on CMV antigenemia assay, 23 patients were antigen-positive and of the remaining 180 antigen-negative patients, 46 were selected as controls matched for age, gender and source of kidney. The 69 kidney recipients (KR) had CMV antibody due to previous infection and were followed up for a period of 6 months after transplantation for the development of active CMV infections by the antigenemia assay. Antibody responses to five CMV-related peptide antigens (pp65, gB, pp150, pp28 and pp38) were investigated by enzyme immunoassay and their presence was correlated with the results of the CMV antigenemia assay. Results: Of the five CMV-related peptide antigens, only gB antigen showed response to the antibody in 10/23 (43.5%) antigen-positive patients and 9/46 antigen-negative patients and the difference was statistically significant (p = 0.048). On the other hand, there was no significant difference in antibody responses between the antigen-positive and antigen-negative KR to the other four CMV peptide antigens (p > 0.05). However, among the antigen-positive KR there was only 1 patient who had antibodies to both pp150 and pp28 antigen, while among the antigen-negative KR, 22 of 46 (47.8%) had the antibodies (p < 0.001). Conclusion: The findings suggest that the combined presence of antibodies against the pp150 and pp28 antigens may indicate a lower risk of CMV reactivation after kidney transplantation.

Pneumatosis Intestinalis

Pneumatosis intestinalis is characterized by the accumulation of gas in the gastrointestinal wall. The histopathologic diagnosis is easily made on resection specimens in which the presence of submucosal or subserosal empty spaces lined by histiocytes and giant cells presents little diagnostic dilemma. In biopsy material, though, the diagnosis is more challenging, as giant cells and histiocytes can be interpreted as granulomatous inflammation indicative of other conditions such as infection or Crohn disease. Nine gastrointestinal biopsies diagnosed as pneumatosis intestinalis from 7 patients were reviewed. Clinical history, radiologic features, and endoscopic findings were obtained from patient records. Five patients presented with blood in the stool (one also with diarrhea) and 2 patients were diagnosed after screening colonoscopies. The endoscopist frequently described polyps or raised mucosal folds (6 cases). In all biopsies submucosal cystic spaces lined by giant cells could be observed. The cysts were intact (2 biopsies), partially intact (5 biopsies), or collapsed (5 biopsies), with 3 biopsies showing 2 cyst architectural conformations. The arrangement of the giant cells lining a rounded or cleft-like space was the most helpful feature in distinguishing pneumatosis intestinalis from granulomatous colitis. Additional useful features included the recognition of "pseudolipomatosis" (n=4) and the presence of round empty spaces in the submucosa resembling fat (n=3). Nonspecific findings included variable inflammation, eosinophilia, mild gland disarray, vascular ectasia and edema, and mild melanosis coli. Two cases were initially given a diagnosis of granulomatous inflammation. One patient with acquired immunodeficiency syndrome and positive cytomegalovirus antigenemia assay had ischemic colitis on the biopsy and another had a subsequent resection with ischemic colitis. A third patient was treated for cytomegalovirus colitis. None had a history of or developed Crohn disease. Pneumatosis intestinalis remains a challenging diagnosis on biopsy material, particularly because endoscopy usually does not suggest that diagnosis. The presence of giant cells in the submucosa, variable inflammation, and crypt disarray can be easily confused with Crohn disease. Attention to the arrangement of the giant cells lining intact, partial, or collapsed cysts is crucial to making the correct diagnosis. Although nonspecific by itself, pseudolipomatosis may also indicate the presence of gas within the tissue and suggest the diagnosis.

Real-Time PCR Assay Compared With Antigenemia Assay for Detecting Cytomegalovirus Infection in Kidney Transplant Recipients

Human cytomegalovirus (CMV) infection is a major cause of morbidity and mortality among kidney transplant recipients. The CMVpp65 antigenemia assay has been used for preemptive therapy. Real-time polymerase chain reaction (PCR) technology for CMV DNA quantification in blood has demonstrated a good correlation with the currently employed CMV antigenemia assay. In this study, 90 renal transplant recipients were prospectively enrolled from July 2004 and May 2005. Monitoring of CMV infection was routinely performed with CMV antigenemia and real-time PCR assays. Real-time plasma PCR and CMV antigenemia assays were assessed on 797 samples. CMV antigenemia correlated with a positive CMV PCR (χ 2 = 78.05; P < .0001). Not only the positive rate but also the number of positive cells correlated with the number of PCR DNA copies (F = 26.07, r 2 = .25, P < .0001). To define an optimal cutoff value of CMV DNA load to initiate treatment in kidney transplant patients, we considered a CMV antigenemia titer of >50 positive cells per 400,000 leukocytes as the gold standard in our previous study. The optimal cutoff value for the quantitative real-time PCR assay was predicted to be 86 copies/μL. Thus, we observed that CMV real-time PCR assay would not completely replace antigenemia assay in kidney transplant recipients, but can be used complementarily to screen antigenemia and monitor preemptive therapy.

Oral Valgancyclovir Versus Intravenous Gancyclovir for Cytomegalovirus Prophylaxis in Kidney Transplant Recipients

Background Prophylaxis against cytomegalovirus (CMV) is a regular practice in organ transplantation. Oral valgancyclovir appears to be an interesting alternative to the usual intravenous form. Patients and Methods We prospectively compared the response of intravenous gancyclovir for 2 weeks (GAN; n = 41) to oral valgancyclovir for 2 weeks (VAL2w; n = 23) or 3 months (VAL3m; n = 46) in kidney transplant recipients receiving induction immunosuppression. CMV antigenemia assay and/or polymerase chain reaction (PCR) were used for viral detection. Patients were followed for a minimum of 6 months posttransplantation. SPSS software was used for statistical analysis using a cutoff of significance as P < .05. Results There was no statistical difference in the demographic features among the study groups. However, human leukocyte antigen (HLA) match was better in the VAL3m group and the patients of this group received less ATG induction immunosuppression (41.3%) compared with the GAN group (100%). The incidence of acute rejection was not different among the study groups. There was a higher incidence of fever with positive CMV tests in the VAL2w group ( P = .035) compared with the other groups, while leukopenia with a negative CMV test was significantly higher in the VAL3m group ( P = .04). The incidence of CMV disease was higher in the VAL2w group (30.4%) compared with the GAN group (14.6%) or the VAL3m group (8.7%). Renal function was significantly worse in the VAL2w group at 3 and 6 months ( P = .011 and .02, respectively). Conclusions Three months oral valgancyclovir prophylaxis for CMV was a more effective regimen compared with intravenous gancyclovir for 2 weeks. Shorter courses were associated with a higher incidence of CMV infection and poorer graft function. Leukopenia observed in patients receiving valgancyclovir may be a drug-related side effect.

Comparison of pp65 antigenemia, quantitative PCR and DNA hybrid capture for detection of cytomegalovirus in transplant recipients and AIDS patients

The cytomegalovirus (CMV) antigenemia assay has been used frequently for rapid diagnosis of CMV infection, and antigenemia threshold values are recommended for triggering preemptive therapy. Hybrid capture of CMV's DNA and quantitative polymerase chain reaction (qPCR) are increasingly being adopted for early detection of CMV. The performance of the antigenemia assay, qPCR in plasma and hybrid capture in leukocytes were compared in 110 immunocompromised patients (38 bone-marrow transplants, 50 renal transplants and 22 AIDS patients). The most sensitive test was hybrid capture for transplants, while antigenemia and the qPCR showed similar performance for patients with AIDS. QPCR and hybrid capture thresholds requiring antiviral therapy were calculated using a receiver-operating-characteristic curve for antigenemia values corresponding to 2 positive cells for bone-marrow transplants and to 10 positive cells for renal transplants and AIDS patients. These threshold values varied with the group of patients considered, with corresponding sensitivities higher than 86% and specificities higher than 76% for hybrid capture, and sensitivities higher than 61% and specificities higher than 75% for qPCR in plasma. Hybrid capture in leukocytes can substitute for antigenemia in the case of transplants, and qPCR in plasma can substitute for it in the case of AIDS patients.

Cytomegalovirus Is Frequently Reactivated and Disappears Without Antiviral Agents in Ulcerative Colitis Patients

The clinical significance of cytomegalovirus (CMV) reactivation complicating ulcerative colitis (UC) patients has been uncertain. It has therefore remained undetermined whether or not CMV reactivation should be treated in UC patients under immunosuppression. The aim of the study was to clarify the natural history of CMV reactivation in UC patients. Sixty-nine UC patients with moderate to severe activity were enrolled in the study. All of the patients were treated with prednisolone, and/or immunosuppressants such as cyclosporine A. We sequentially monitored CMV reactivation every 2 wk up until 8 wk using the CMV antigenemia (Ag) assay and plasma quantitative real-time polymerase chain reaction (PCR) assay for CMV. Immunoglobulin (Ig) G for CMV was positive in 48 patients (69.6%) and negative in 21 patients (30.4%). CMV was reactivated in 25 patients out of the 48 seropositive patients (52.1%) during the study period. The CMV Ag and PCR values were low and none of the patients showed any evidence of CMV infection on biopsy specimens by hematoxylin and eosin staining. While gancylovir (GCV) was not used except in two patients, clinical outcomes including rates of remission and colectomy were not significantly different among the CMV reactivation-positive, -negative, and CMV IgG negative groups. Furthermore, CMV disappeared without GCV in most of the CMV reactivation-positive patients. CMV is frequently reactivated in active UC patients; however, it disappears without antiviral agents. Therefore, antiviral therapies should not be necessary for most UC patients with only CMV reactivation as long as CMV Ag values are low.

Low Incidence of Cytomegalovirus Infection Associated with Rapid Cell-Mediated Immune Reconstitution after Cord Blood Transplantation Using Full Conditioning Regimen Containing 12Gy Total Body Irradiation.

The one of crucial questions in cord blood transplantation (CBT) is whether naïvity of cord blood lymphocytes could gain antigen-specific cellular immunity during early phase of transplant. Cytomegalovirus (CMV) infection is serious clinical problem in allogeneic transplant recipients and T cell immunity has known to have an important role in control of virus replication and prevention.During 1998 and 2006, 111 adults has received myeloablative regimens including 12 Gy of total body irradiation followed by CBT and a standard cyclosporine and methotrexate combination as GVHD prophylaxis in our institute. Patients also received intravenous immunoglobulin from day −3 to day 120 if the immunoglobulin level in the serum was less than 500 mg/dl. CMV antigenemia assay was performed twice a week after neutrophil recovery until day 120. Once CMV antigenemia is positive, patients received 5 mg/kg ganciclovir (GCV) once daily for at least 2 weeks as preemptive therapy. Ninety-two patients achieved engraftment with full donor chimerism and survived without disease relapse at the time of 120 days after CBT (82.8%). None of these 92 recipients had CMV disease during first 4 months after CBT.We have investigated the association of CMV reactivation status and their immune reconstitution process for 4 months after CBT in 39 patients who received CBT from 2002 to 2006 in our institute. CMV-specific CD4+ and CD8+ T cell recoveries were assessed by detection of interferon-g (IFN-g) producing cells with CMV antigen stimulation using intracellular cytokine staining. The positive was defined as more than 0.1% IFN-g positive cells among CD4+ or CD8+ T cell population.Six of 39 patients were CMV sero-negative and 33 patients were sero-positive. None of 6 CMV sero-negative receipients and 31 of 33 CMV sero-positive recipients observed CMV reactivation and received GCV therapy within the first 4 months.CMV-specific CD4+ T cells were detected in 30 of 31 recipients with positive CMV antigenemia (% positive: 55% at 1 month and 85% at 2 month), on the other hand, CMV-specific CD8+ T cells were detected in 14 out of 31 cases (% positive: 14% at 1 month and 22% at 2 month), both of which were comparable to post-bone marrow or peripheral blood transplants (CMV-specific CD4+ T cells were detected 18 of 21 recipients with positive CMV antigenemia and CMV-specific CD8+ T cells were detected in 12 out of 21).These data suggest that post-thymic naive T lymphocytes in cord blood might obtain memory and effector function in vivo with antigen-specific manner during early phase of post-transplant.

Prevention of Cytomegalovirus Infection by Valaciclovir after Allogeneic Bone Marrow Transplantation from an Unrelated Donor

In this prospective single-center study, we evaluated the efficacy and safety of valaciclovir (VACV) in the prevention of cytomegalovirus (CMV) infection after allogeneic bone marrow transplantation (BMT). The study population consisted of 12 patients who underwent allogeneic BMT from an unrelated donor. Patients received acyclovir (ACV) intravenously until they became able to take VACV orally. VACV was administered at a daily dose of 3000 mg and continued until day 100. CMV infection was monitored by CMV antigenemia assay and real-time polymerase chain reaction analysis of plasma. Thirty-five patients who did not receive any form of CMV chemoprophylaxis served as control subjects. CMV infection was detected in 4 (33.3%) of the 12 patients and in 24 (68.6%) of the 35 control subjects (P < .05). The onset of CMV infection was significantly delayed in the VACV group (median, day 43) compared with the control group (median, day 28.5; P < .01). Gastrointestinal symptoms as an adverse event due to VACV administration were observed in 2 patients. The plasma levels of ACV after VACV administration were measured in 8 patients and were similar to those in the healthy subjects. In conclusion, VACV shows normal absorption, even in the early posttransplantation period, and may prevent or delay CMV infection effectively and safely in allogeneic BMT recipients.

Clinical study of different methods on early diagnosis and monitoring of neonatal congenital cytomegalovirus infection

目的 探讨外周血白细胞巨细胞病毒(cytomegalovirus,CMV)抗原(即刻早期抗原和早期抗原)检测、唾液聚合酶链反应(PCR)检测CMV-DNA和血清学检测CMV-IgM三种实验方法在诊断和监测新生儿先天性CMV感染中的作用.方法对98例患儿之母在孕期血CMV-IgM阳性的高危新生儿出生后14 d内检查血CMV-IgM、外周血白细胞CMV抗原和唾液PCR-CMV-DNA,比较三种方法的检测结果,并对新生儿进行临床观察和随访.结果(1)98例中,48例诊断先天性CMV感染.症状性感染7例,无症状性感染41例;无一例CMV-IgM阳性.症状性感染组CMV抗原、PCR阳性检出率分别为7/7、5/7;无症状性感染组阳性检出率分别为71%(29/41)、46%(19/41).CMV抗原检测法、PCR检测法的诊断敏感性分别为75%、54%.症状性感染儿每5万白细胞中CMV阳性细胞数16～52个,无症状性感染儿3～31个,症状性感染儿CMV抗原指数水平显著高于无症状感染儿(P＜0.05).(2)随访10例患儿,2例症状性感染儿CMV抗原和PCR转阴,症状消失;1例CMV肝炎治疗后CMV抗原和PCR检测仍阳性,最后发展为肝硬化.7例无症状性感染儿,CMV抗原在6个月内转阴或减少至低水平;2例伴唾液PCR阳性,复查时1例转阴,1例仍阳性.结论CMV抗原检测法具有早期、敏感、量化的特点,PCR法能发现潜伏性感染,两者联合应用能提高诊断阳性率,对治疗和随访患儿提供有效帮助;CMV-IgM法对先天性CMV感染的早期诊断的敏感性低。

Cidofovir for cytomegalovirus reactivation in pediatric patients after hematopoietic stem cell transplantation

Background: Cidofovir (CDV) is a nucleotide analogue with broad antiviral activity. This drug has a very favorable pharmacokinetic profile that enables intermittent dosing, but the potential for nephrotoxicity has hitherto restricted its use in stem cell transplant recipients. Data on pediatric patients are limited. Objectives: To report the efficacy and toxicity of CDV in a group of pediatric patients with cytomegalovirus (CMV) reactivation after allogeneic stem cell transplantation. Study design: Prospective evaluation of safety and efficacy of CDV used pre-emptively for CMV reactivation in 10 out of 30 children who underwent allogeneic hematopoietic stem cell transplantation from January 2000 to December 2001. In all the patients but one, CDV was used as second-line therapy (after foscarnet or ganciclovir) of CMV reactivation. Results: Overall, 12 courses of CDV were administered with a median 5 doses per course, range 1–6 (two patients were treated twice). Considering the first CDV treatment episode, 8 out of 10 patients had positive CMV antigenemia assay when they started CDV. Five of eight antigenemic patients responded completely while three were switched to foscarnet or ganciclovir, respectively, due to increasing (one) or persistent CMV antigenemia (two). Overall, the therapy with CDV was well tolerated, but it was withdrawn in one patient due to a two-fold increase in the baseline creatinine level. This patient concurrently had a high tacrolimus blood level. Conclusion: Safety is the major concern regarding the use of CDV but the adoption of probenicid, intravenous hydration and anti-emetic therapy improved its tolerability profile. Our data suggest that CDV has an acceptable toxicity and would deserve further controlled studies in the setting of pre-emptive therapy for CMV.