Developed Cytomegalovirus Disease Research Articles

Delayed-Onset Primary Cytomegalovirus Disease and the Risk of Allograft Failure and Mortality after Kidney Transplantation

During the contemporary era of antiviral prophylaxis, the impact of delayed-onset primary cytomegalovirus (CMV) disease on the outcome of kidney transplantation is not known. We evaluated the incidence, clinical features, risk factors, and outcomes of CMV disease among high-risk kidney transplant recipients. The medical records of CMV-seronegative recipients of kidney transplants from CMV-seropositive donors were reviewed. Cox proportional hazards regression was used to identify factors associated with CMV disease and to assess its impact on allograft loss and mortality. None of the 176 CMV-seronegative recipients of kidney transplants from CMV-seropositive donors developed breakthrough CMV disease during a median of 92 days (interquartile range, 90-92 days) of oral ganciclovir or valganciclovir prophylaxis. Thereafter, 51 patients (29%) developed CMV disease at a median of 61 days (interquartile range, 40-143 days) after stopping antiviral prophylaxis. Early-onset bacterial and fungal infection (hazard ratio, 3.61; 95% confidence interval, 1.78-7.33; p < .001) and a Charlson comorbidity index > or =3 (hazard ratio, 2.21; 95% confidence interval, 1.15-4.22; p = .011) were associated with a higher risk of delayed-onset primary CMV disease, and postrejection antiviral prophylaxis (hazard ratio, 0.29; 95% confidence interval, 0.09-0.94; P = .039) was associated with a lower risk of such CMV disease. A time-dependent Cox regression analysis revealed a statistically significant association between tissue-invasive CMV disease and allograft loss or mortality (hazard ratio, 2.85; 95% confidence interval, 1.22-6.67; P = .016). This study of a large cohort of CMV-seronegative recipients of kidney transplants from CMV-seropositive donors illustrates the ongoing challenge of delayed-onset primary CMV disease and its impact on transplantation outcomes despite antiviral prophylaxis. Better strategies for CMV disease prevention after kidney transplantation are warranted.

Cytomegalovirus Disease in Renal Transplant Recipients: A Single-Center Experience

Cytomegalovirus (CMV) disease is an important complication and an independent risk factor for acute rejection and recipient morbidity-mortality. The aim of this study was to review the results of CMV disease in renal transplant recipients. Method. We have retrospectively analyzed CMV disease in 120 renal transplant recipients and recorded the demographic features, clinical manifestations, and immunosuppressive regimens. Results. Twenty-nine recipients (24.1%) developed CMV disease after a median interval of 2.8 ± 2,6 months from transplantation. CMV disease developed in 36.3% of recipients who received basiliximab as induction therapy and 21.4% of recipients who were treated with anti-thymocyte globulin (ATG). The most commonly used immunosuppressive regimen was cyclosporine-A (CsA)-based (79.3%). The mean cumulative steroid dose until the diagnosis was 3,600 mg methyl prednisolone per patient. Malaise, fever, and diarrhea were the most common symptoms. Gastritis, pneumonia, and transaminitis were the most commonly seen end-organ involvements. Frequent laboratory findings were leukopenia (34.5%), increased serum creatinine level (34.5%), and leukocytosis (20.7%). We performed renal biopsy to seven patients and detected acute rejection in four patients. In 25 patients, immunosuppressive treatment was modified. Relapsing CMV disease was seen in seven patients. Conclusion. In our study, CMV disease was seen in recipients who were treated with basiliximab, a finding similar to recipients who were treated with ATG.

Effect of Cytomegalovirus Prophylaxis with Acyclovir on Renal Transplant Survival

It is recognized that cytomegalovirus (CMV) infection in transplant recipients may lead to graft loss. Prophylaxis with acyclovir has therefore gained widespread acceptance, but the debate on whether this intervention improves long term graft survival continues. All patients who received renal grafts at the National Renal Transplant Centre, Dublin, between January 1992 and December 1999 were retrospectively analyzed. During this time period, patients who were CMV positive and/or had received grafts from CMV-positive donors were administered prophylactic oral acyclovir 800 mg thrice daily, adjusted for calculated creatinine clearance, from the first day post-transplantation. This treatment was continued for three months unless the graft failed or the patient developed CMV disease or died. Graft and patient outcomes were compared in recipients who received acyclovir with those who did not. Over the study period, 935 patients received renal transplants in our center, of whom 487 were administered acyclovir. The incidence of CMV disease was 3.3 cases per 100 patients per annum in those who required prophylaxis. Despite prophylaxis, graft outcomes were found to be significantly worse (p value < 0.001) in the group that qualified for acyclovir. We conclude that acyclovir provides incomplete protection from the negative impact of CMV on graft survival.

Impairment of cytomegalovirus-specific cellular immune response as a risk factor for cytomegalovirus disease in transplant recipients

Human cytomegalovirus (CMV) infection is common in most people but nearly asymptomatic in immunocompetent individuals. After primary infection the virus persists throughout life in a latent form in a variety of tissues, particularly in precursor cells of the monocytic lineage. CMV reinfection and occurrence of disease are associated with immunosuppressive conditions. Solid organ and bone marrow transplant patients are at high risk for CMV disease as they undergo immunosuppression. Antiviral treatment is effective in controlling viremia, but 10-15% of infected patients can experience CMV disease by the time the drug is withdrawn. In addition, long-term antiviral treatment leads to bone marrow ablation and renal toxicity. Furthermore, control of chronic CMV infection in transplant recipients appears to be dependent on the proper recovery of cellular immunity. Recent advances in the characterization of T-cell functions and identification of distinct functional signatures of T-cell viral responses have opened new perspectives for monitoring transplant individuals at risk of developing CMV disease.

Rituximab therapy increased post-transplant cytomegalovirus complications in Non-Hodgkin’s lymphoma patients receiving autologous hematopoietic stem cell transplantation

The use of monoclonal antibody, rituximab, had been reported to be associated with some severe viral infections. The inference of rituximab therapy and post-transplant cytomegalovirus (CMV) infectious complications in non-Hodgkin's lymphoma (NHL) patients is still unclear now. From 2002 to 2005, 46 patients with relapsed indolent or high-risk aggressive B cell NHL who received rituximab (17 patients) or not (29 patients) before autologous hematological stem cell transplantation (HSCT) in one institute were retrospectively analyzed for the risk factors of CMV complications after transplantation. Pre-transplant and post-transplant CMV infectious conditions, conditioning regimens, transplant types, and post-transplant complications were recorded. Post-transplant infectious complications were followed up until 6 months after transplantation. Seventeen of 46 patients received rituximab before HSCT. Three of them suffered from CMV infection and two of them developed CMV disease. All of the patients with CMV disease recovered after ganciclovir and CMV-specific immunoglobulin therapy. Twenty-nine of 46 patients without rituximab treatment before HSCT did not have CMV complications after HSCT. The risks to develop CMV infections after autologous HSCT were higher in rituximab-treated patients (17.6% vs 0%, p = 0.045, Fisher exact test, two-sided). The risks to develop CMV diseases had higher trend with rituximab therapy than without rituximab therapy (11.7% vs 0%, p = 0.131, Fisher exact test, two-sided). The NHL patients receiving rituximab therapy had higher risk to develop CMV infectious complications after autologous HSCT.

CMV-specific T cell therapy

Human cytomegalovirus (CMV) infection continues to be one of the most important and life threatening complications after allogeneic stem cell transplantation (SCT). The reconstitution of CMV-specific T cell responses after SCT has been demonstrated to be protective against the development of CMV disease. To improve T cell immunity against CMV in bone marrow transplant patients, different strategies were explored. On one hand, CMV-specific T cells can be selected from the donor, and can be transferred to the patient without any further in vitro expansion. On the other hand, CMV-specific T cells can be activated and expanded in vitro by stimulation with antigen presenting cells (APCs) loaded with specific proteins or peptides. Here, we review the therapeutic application of CMV-specific T cells to fight CMV infection.

Impact of Valganciclovir Prophylaxis on the Development of Severe Late-Cytomegalovirus Disease in High-Risk Solid Organ Transplant Recipients

Background With the introduction of prolonged prophylaxis with valganciclovir in cytomegalovirus (CMV) donor/recipient serodiscordance (D+/R−) patients, concerns about a high incidence of late and invasive CMV disease associated with mortality have emerged. We compared the characteristics of CMV disease in D+/R− patients receiving prolonged valganciclovir prophylaxis with R+ patients. Methods We prospectively followed all solid organ transplant recipients from January 2004 to December 2005. CMV prophylaxis with valganciclovir or ganciclovir was administered as follows: donor- recipient serodiscordance (D+/R−), 12 weeks; induction with antithymocyte globulin or acute rejection episodes requiring steroid pulses, 15 to 30 days; and CMV R+ double kidney-pancreas, 15 days. Transplant characteristics and the development of CMV disease variables were collected for all patients. We defined 2 groups according to the risk of CMV disease: CMV donor/recipient mismatch (D+/R−) and recipient CMV-positive (R+) groups. Results During the study period we performed 481 solid organ transplantations: 237 kidney, 34 kidney-pancreas, 157 liver, 38 heart, 13 liver-kidney, and 2 heart-kidney. Overall, 36 patients developed CMV disease (7.5%). CMV donor-recipient mismatch (D+/R−) was associated with a greater risk of CMV disease compared with CMV-positive recipients (16% vs 7%; P = .036). Prophylaxis against CMV was longer in the D+/R− group (mean days 73 vs 15; P < .001). CMV disease appeared later in the D+/R− than in R+ group (mean days 123 vs 59; P < .001). We observed a trend toward a lower incidence of tissue-invasive CMV disease among the D+/R− group compared with the R+ group without significance (14% vs 41%; P = .382). Three patients died in the first 30 days after the onset of CMV disease, all of them in the R+ group. Conclusions In our setting, high-risk patients (D+/R−) receiving prolonged prophylaxis with valganciclovir developed later CMV disease, but this was neither more tissue-invasive nor more life-threatening than in the R+ group.

Incidence and Clinical Features of Ganciclovir- Resistant Cytomegalovirus Disease in Heart Transplant Recipients

The incidence and clinical and virologic aspects of ganciclovir-resistant cytomegalovirus (CMV) disease have not been well-characterized in heart transplant recipients. We retrospectively analyzed all patients who underwent their first heart transplantation during the period from 1 January 1995 through 30 June 2005 at a single health care center. Cox proportional hazard regression was used to assess the relationship between clinical variables and CMV disease. Portions of the UL97 gene were sequenced in patients with slow clinical and/or virologic response to ganciclovir therapy. Cytomegalovirus disease developed in 32 (11.7%) of 274 patients at a median of 4.2 months after transplantation (range, 1.8-11.6 months after transplantation) and was independently associated with donor-seropositive/recipient-seronegative (D+/R-) serostatus (adjusted hazard ratio, 6.93; P<.001). The incidence of ganciclovir-resistant CMV disease was 1.5% overall (4 of 274 patients), 5% among D+/R- serostatus recipients (4 of 80 patients), and 12.5% among patients who developed CMV disease (4 of 32 patients). Ganciclovir-resistant CMV disease was significantly associated with D+/R- serostatus (4 [5%] of 80 vs. 0 [0%] of 153 patients; P=.02), greater prior exposure to ganciclovir (median duration of exposure, 150 vs. 69 days; P=.003), and substantial morbidity, including prolonged CMV-associated hospitalization (median duration of hospitalization, 66 vs. 0 days; P<.01). CMV disease, including ganciclovir-resistant disease, is an important clinical problem in D+/R- heart transplant recipients who receive antiviral prophylaxis. Strategies specifically designed to reduce the incidence and impact of CMV disease in this population are warranted.

Comparable incidence and severity of cytomegalovirus infections following T cell-depleted allogeneic stem cell transplantation preceded by reduced intensity or myeloablative conditioning

Reports on infectious complications following reduced intensity conditioning (RIC) before allogeneic stem cell transplantation (allo-SCT) are equivocal. This prospective follow-up study compared the impact of cytomegalovirus (CMV) infections following RIC with fludarabine, ATG and busulphan or conventional myeloablative conditioning (MAC). Forty-eight RIC and 59 MAC patients were enrolled. The occurrence and severity of CMV infections within 100 days following allo-SCT were assessed, using plasma CMV DNA load kinetics. CMV DNAemia was observed in 21 RIC (60%) and in 19 MAC (44%) patients at risk for CMV. The mean CMV DNAemia free survival time was comparable following RIC and MAC: 70 days (95% (confidence interval) CI: 59-80 days) and 77 days (95% CI: 68-86 days), respectively (P=0.24). Parameters indicative for the level of CMV reactivation, including the area under the curve of CMV DNA load over time as well as the onset, the peak values and duration of CMV infection episodes, the numbers and duration of CMV treatment episodes and recurrent infections, were not different in both groups. During follow-up, none of the patients developed CMV disease. RIC with fludarabine, ATG and busulphan demonstrated safety comparable to conventional MAC with regard to frequency and severity of CMV infections within 100 days following T cell-depleted allo-SCT.

Surveillance of cytomegalovirus (CMV) DNAemia in pediatric allogeneic stem cell transplantation: incidence and outcome of CMV infection and disease

Cytomegalovirus (CMV) remains a serious problem after hematopoietic stem cell transplantation (HSCT). To investigate the incidence of CMV infection and outcome we retrospectively analyzed 70 consecutive pediatric allogeneic HSCTs monitored by CMV polymerase chain reaction (PCR), with at least 1-year follow-up or until death. All patients at risk for CMV infection (CMV-seropositive patients and CMV-seronegative recipients transplanted from CMV-seropositive donors) received hyperimmune anti-CMV globulins whereas in the group of HSCT patients with both donor and recipient CMV negativity, polyvalent immunoglobulins were given, both at a dose of 400 mg/kg. All patients received acyclovir at prophylactic doses for at least 6 months. Patients were monitored twice a week by CMV PCR. Patients with 2 positive results for CMV DNAemia received ganciclovir for 14 days and continued until 2 consecutive negative results were obtained. The incidence of CMV DNAemia was 12.8% (9/70) in the whole group, with significant higher risk for patients with CMV-seropositive recipient status, 8 out of 22 (36%), vs. patients with seronegative status, 1 out of 48 (2%) (P=0.0002). Three out of 9 patients with DNAemia developed CMV disease despite adequate preemptive treatment. The transplant-related mortality was higher in the CMV-seropositive recipient group (P=0.05). Age, use of hyperimmune anti-CMV globulins at a high dose, and the low incidence of graft-versus-host disease might be contributing factors to this low incidence.

Leukopenia Complicates Cytomegalovirus Prevention After Renal Transplantation With Alemtuzumab Induction

Cytomegalovirus (CMV) is a major cause of morbidity after transplantation. Valganciclovir (VGCV) is commonly utilized for CMV prophylaxis but can cause leukopenia, with risk compounded by the use of myelosuppressive immunosuppression. By utilizing a preemptive therapeutic strategy with VGCV targeted only toward patients at risk for developing CMV disease, the rate and extent of leukopenia may be reduced. VGCV prophylactic and preemptive strategies were compared in renal transplant recipients receiving alemtuzumab induction and prednisone-free maintenance with tacrolimus and mycophenolate mofetil (MMF). Patients were risk-stratified by CMV serologic status. All donor seropositive/recipient seronegative (D+/R-) patients, February 2002-January 2004 (n=32), received prophylaxis with VGCV 450 mg daily for 3 months. Outcomes of D+/-/R+ patients were compared. Patients in the first cohort, February 2002-October 2002 (n=61), received prophylaxis as described. In the second cohort, October 2002-January 2004 (n=110), patients were monitored by quantitative CMV-polymerase chain reaction (PCR) every 2 weeks for 3 months. If the CMV load was above laboratory threshold, VGCV 450 mg daily was initiated for 1 month or until viremia cleared. Comparing preemptive therapy versus prophylaxis in D+/-/R+ patients, there was a lower incidence of leukopenia (67% vs. 82%, P=0.039) and trend toward less granulocyte-colony stimulating factor (G-CSF) use (24% vs. 33%, P=0.196), but higher CMV disease rate (15% vs. 3%, P=0.02). One limitation was strategy compliance: 41% (7 of 17) of preemptive patients who developed CMV missed at least 1 CMV-PCR before diagnosis. One-year patient (98.2% vs. 98.4%) and death-censored graft (100% vs. 98.4%) survival was similar. Antiviral toxicity may be decreased with preemptive therapy, but effectiveness for CMV prevention seems dependent upon monitoring compliance.

Ex Vivo Expansion and Prophylactic Infusion of CMV-pp65 Peptide-Specific Cytotoxic T-Lymphocytes following Allogeneic Hematopoietic Stem Cell Transplantation

Cytomegalovirus reactivation and infection post-allogeneic hematopoietic stem cell transplant continue to cause morbidity and mortality. Current pharmacologic therapies are limited by side effects. Adoptive transfer of ex vivo generated cytomegalovirus-specific T cells has the potential to restore immunity, prevent cytomegalovirus, and circumvent the need for pharmacologic therapies. We have generated donor-derived cytomegalovirus-specific cytotoxic T cells using dendritic cells pulsed with the HLA-A2 restricted nonapeptide NLVPMVATV (NLV) derived from the cytomegalovirus-pp65 protein. These cytotoxic T cells have been given prophylactically to 9 recipients aged 4 to 65 years on or after day 28 post-allogeneic hematopoietic stem cell transplant. Only 2 of 9 recipients received T cell depletion in vivo or in vitro. There were no immediate adverse reactions to the infusions. During 97-798 days of follow-up, 2 recipients developed cytomegalovirus reactivation; neither developed cytomegalovirus disease or required pharmacotherapy. Three recipients developed acute graft versus host disease after infusion. Two recipients died, 1 from thrombotic thrombocytopenia purpura secondary to cyclosporine, 1 from complications of graft versus host disease. A transient increase in numbers of cytomegalovirus-specific T cells demonstrated by NLV-tetramer binding was seen in 6 recipients. Prophylactic adoptive transfer of NLV-specific T cells is safe and may be effective in preventing cytomegalovirus reactivation.

Positive Pretransplantation Cytomegalovirus Serology Is a Risk Factor for Cardiac Allograft Vasculopathy in Children

Cytomegalovirus (CMV) infection has been implicated as a cause of posttransplantation coronary artery disease in adults. The purpose of this retrospective observational study was to evaluate the effect of CMV on outcome after heart transplantation in children. Risk factors tested were recipient age, sex, and pretransplantation CMV serology; use of anti-CMV prophylaxis; posttransplantation evidence of CMV infection; and donor CMV serology. Transplantations were stratified traditionally according to CMV risk as low risk (recipient negative/donor negative), intermediate risk (recipient positive), and high risk (recipient negative/donor positive). Primary outcome measures were (1) development of coronary artery vasculopathy, (2) mortality (or graft loss) that occurred outside the early postoperative period, and (3) death (or graft loss) due to vasculopathy. Analysis was by proportional hazards modeling. A total of 165 children underwent heart transplantation, with a mean age at transplantation of 7.8 (SD 5.6) years. Thirty-two children had laboratory evidence of CMV infection after transplantation, but only 6 developed CMV disease or syndrome. Traditional CMV risk stratification correlated well with CMV infection but did not predict mortality, coronary artery disease, or coronary death. In contrast, positive recipient CMV was the only independent predictor of all 3 outcome measures: coronary artery disease (hazard ratio=3.6), all-cause mortality (partial hazard ratio=4.1), and coronary death (hazard ratio=4.6). In children, pretransplantation recipient CMV status is a more powerful predictor for the development of clinically significant vasculopathy and subsequent death than traditional risk stratification. This phenomenon warrants further investigation.

Reduced dose of foscarnet as preemptive therapy for cytomegalovirus infection following reduced‐intensity cord blood transplantation

Although foscarnet is a promising alternative for the treatment of cytomegalovirus (CMV) infection, its toxicity can be significant in patients with advanced age. We retrospectively reviewed medical records of 123 patients (median age of 55; range, 17-79) who received reduced-intensity cord blood transplantation (RI-CBT). Patients preemptively received reduced-dose foscarnet 30 mg/kg twice daily when CMV antigenemia exceeded 10/50,000. Sixty-three patients developed CMV antigenemia on a median of day 34, and 29 received foscarnet preemptively. The median level of CMV antigenemia at the initiation of foscarnet was 30. Median duration of foscarnet administration was 24 days. Adverse effects included electrolyte abnormalities (n=19), renal impairment (n=13), and skin eruption requiring discontinuation of foscarnet (n=1). Preemptive therapy of foscarnet was completed in 18 patients. Seven patients died during foscarnet use without developing CMV disease. The remaining 3 developed CMV enterocolitis 5, 14, and 17 days after initiation of foscarnet. All of them were successfully treated with ganciclovir or foscarnet. Reduced dose of foscarnet is beneficial to control CMV reactivation following RI-CBT; however, it has considerable toxicities in RI-CBT recipients with advanced age. Further studies are warranted to minimize toxicities and identify optimal dosages.

Non‐bacterial infections in allogeneic non‐myeloablative stem cell transplant recipients

Data on non-bacterial infections during allogeneic non-myeloablative hematopoietic stem cell transplantation (HSCT) are widely different. We evaluated data on 48 consecutive patients who received a conditioning regimen with fludarabine and cyclophosphamide (73%) or fludarabine and total body irradiation (27%) and then underwent allogeneic non-myeloablative HSCT. Cytomegalovirus (CMV) infection was common and occurred in 48% of patients; 3 patients developed CMV disease, and all survived. CMV reactivation was found to be common with both conditioning regimens in our patient population. Invasive aspergillosis occurred in 4 patients (8%) and 3 died. Other serious non-bacterial infections were uncommon. Review of the available literature on non-myeloablative HSCT suggests that the frequency and type of opportunistic infections vary considerably.

Oral Ganciclovir Versus Low-Dose Valganciclovir for Prevention of Cytomegalovirus Disease in Recipients of Kidney and Pancreas Transplants

The optimal regimen for prophylaxis of cytomegalovirus (CMV) disease after kidney and/or pancreas transplantation remains unclear. We compared the effectiveness of three months of oral ganciclovir (3 g/day) versus low-dose valganciclovir (450 mg/day) for CMV prophylaxis. We performed a retrospective cohort study of patients at our center who received kidney and/or pancreas transplants between January 2000 and April 2003. We used a Cox proportional hazards model to examine the relationship between baseline covariates, including type of CMV prophylaxis, and time to development of CMV disease. Of the 500 patients (295 ganciclovir, 205 valganciclovir), 22 patients (4.4%) developed CMV disease (mean time to CMV disease, 163+/-85 days). Sixteen of the ganciclovir patients (5.4%) and six of the valganciclovir patients (2.9%) developed CMV disease (P=0.18). By CMV serostatus, the incidence of CMV disease during the first posttransplant year was 8.5% among donor-seropositive, recipient-seronegative (D+/R-) patients, 8.6% among D+/R+ patients, 2.9% among D-/R+ patients, 1.0% among D-/R- patients, and 0.9% among patients for whom documentation of CMV serostatus was incomplete. In the unadjusted Cox proportional hazards analysis, race/ethnicity, type of transplant, type of antiviral prophylaxis, CMV serostatus, and use of mycophenolate mofetil were each associated with risk of developing CMV disease. In the adjusted, multivariable model, only CMV serostatus was associated with development of CMV disease. Three months of low-dose valganciclovir (450 mg/day) was as effective as ganciclovir (3 g/day) for prophylaxis of CMV disease after kidney and/or pancreas transplantation.

Association Between Mannose-Binding Lectin Deficiency and Cytomegalovirus Infection After Kidney Transplantation

Mannose-binding lectin (MBL) deficiency has been suggested as a risk factor for certain viral infections. However, there is no data about the possible association between MBL deficiency and cytomegalovirus (CMV) infection, especially after organ transplantation. We measured plasma MBL levels in 16 kidney transplant recipients with high-risk CMV serostatus (donor-positive/recipient-negative). MBL deficiency was diagnosed if MBL levels were <500 ng/mL. Of these 16 patients, seven developed CMV disease, four developed asymptomatic CMV infection, and in five patients CMV replication was not detected. Overall, 9 of 16 patients (56%) had MBL deficiency: five of seven (71%) patients with CMV disease, four of four (100%) patients with asymptomatic CMV infection, and zero of five (0%) patients without CMV infection (P=0.005; CMV infection/disease versus no infection). MBL deficiency may be a significant risk factor for the development of CMV infection in kidney transplant recipients, suggesting a role for innate immunity in the control of CMV infection after organ transplantation.

Pseudallescheria boydii infection after liver retransplantation

Pseudallescheria boydii infection after liver retransplantation

Development of new cytomegalovirus UL97 and DNA polymerase mutations conferring drug resistance after valganciclovir therapy in allogeneic stem cell recipients

Background We report on two allogeneic stem cell transplant recipients who developed cytomegalovirus disease associated with new viral mutations that conferred antiviral drug resistance. Methods Blood specimens obtained during symptomatic disease were analyzed for mutations in the CMV UL97 and DNA polymerase genes and new mutations were assessed by recombinant phenotyping. Results Rising cytomegalovirus (CMV) antigenemia occurred after 4–5 months of preemptive valganciclovir therapy, followed by symptomatic CMV disease including fatal pneumonia in one case. In one case, a new viral UL97 mutation (deletion of codons 601–603) was found which conferred 15-fold increased ganciclovir resistance. In the other case, a known UL97 resistance mutation M460V and a new DNA polymerase ( pol) mutation D413A were found. D413A conferred ganciclovir and cidofovir resistance. Conclusions Known and newly discovered drug resistance mutations arising during preemptive therapy may complicate post-transplant CMV disease in stem cell recipients. Improved recombinant phenotyping methods enable the rapid quantitation of the resistance conferred by newly identified UL97 and pol mutations.

High Incidence of Cytomegalovirus Reactivation and Diseases Following Reduced-Intensity Cord Blood Transplantation for Adult Patients.

Backgrounds: Although cytomegalovirus (CMV) infection is one of the major complication after allogeneic haematopoietic stem-cell transplantation, there is little information on the incidence and clinical features of CMV infection after reduced-intensity cord blood transplantation (RI-CBT) for Adult Patients.Patients/methods: We reviewed medical records of 166 patients who received RI-CBT at Toranomon Hospital between January 2002 and December 2005. Fifty Patients were excluded due to early death before engraftment, primary graft failure, and those who CMV antigenemia was not properly monitored. The remaining 116 patients were included in the analysis. Median age of the patients was 52 years (range 17–79). Underlying diseases were AML (n=34), ALL (n=13), MDS(n=15), ATL (n=13), CML (n=5), NHL (n=20), and others (n=16). Ninety-four of those were chemo-refractory, and the other were chemo-sensitive. Conditioning regimens comprised of fludarabine 125 mg/m2, melphalan 80 mg/m2 and total body irradiation (TBI) of (2–4 Gy)(n=107) and others(n=9). Graft-versus-host disease (GVHD) prophylaxis was cyclosporine (n=59) or tacrolimus (n=57). Median number of total nucleated cells and CD34+ cells was 2.6×106 cells/kg (range, 1.8–4.8), and 0.72×105 cells/kg (range, 0.1–4.4) respectively. HLA disparity was 6/6 (n=2), 5/6 (n=17), 4/6 (n=95), and 3/6 (n=2). All the patients were monitored weekly for CMV-antigenemia and received pre-emptive ganciclovir or foscarnet therapy.Results: Positive antigenemia was observed in 81 patients (70%) at a median of 34 days (range, 0–87) after RI-CBT. Median of maximal numbers of CMV antigen positive cell was 15 per 50,000 leukocytes (range, 1–848). CMV diseases developed in 22 patients (19%) at a median of 45 days (range, 20–350); enterocolitis (n=20), pneumonia (n=2), and adrenalitis (n=1). CMV-antigenemia remained negative in five patients with enterocolitis, even when CMV disease was diagnosed. Twenty of the 22 patients were improved using ganciclovir or foscarnet with only one recurrence. The other two had fatal outcome from CMV disease. Despite improvement of CMV disease, thirteen of the remaining 20 patients died due to infection (n=6 bacterial sepsis: 4, bacterial pneumonia: 1, gas gangrene:1), GVHD (n=2), disease progression (n=3), and others (n=2). Multivariate analysis revealed that grade II–IV acute GVHD were associated with on increased risk and developing CMV disease (p<0.05).Discussion: CMV reactivation and diseases develop at high frequency and at early period after RI-CBT. Once the disease has established, many of them had poor prognosis despite effective antiviral therapy. Further preventive strategy, such as development of more sensitive monitoring methods, or better prevention and control of GVHD, are warranted.