Strategies for the prevention of cytomegalovirus disease after marrow transplantation

The purposes of this review are to examine the epidemiology of disease due to cytomegalovirus (CMV) in recipients of autologous and allogeneic marrow transplants and to compare different antiviral regimens used for the prevention of such disease in recipients of allogeneic marrow transplants, with an emphasis on ganciclovir. In seven studies, ganciclovir reduced the incidence of CMV infection and disease after allogeneic marrow transplantation. In one study mortality after transplantation was reduced because of a decreased rate of CMV-related death among ganciclovir-treated patients. Ganciclovir was effective when given to all CMV-seropositive patients (prophylaxis) or to patients who were considered at high risk for CMV disease on the basis of a positive surveillance culture (early treatment). The effectiveness of ganciclovir for the prevention of CMV infection and disease is limited by drug-induced neutropenia. Experience with other antiviral agents, such as foscarnet, has been limited. Initial studies of the adoptive transfer of CMV-specific CD8+ cytotoxic T cells have been conducted. In short, ganciclovir is currently effective for the prevention of CMV disease in allogeneic marrow transplant recipients, but its usefulness is limited by neutropenia. Future studies must be aimed at confining the toxicity of ganciclovir to patients at the highest risk for CMV disease.     

Late cytomegalovirus disease in marrow transplantation is predicted by virus load in plasma

Late occurrence of cytomegalovirus (CMV) disease after day 100 after bone marrow transplantation has become an increasing problem; whether a quantitative measurement of CMV DNA in plasma by polymerase chain reaction (P-PCR) could be predictive of such disease was investigated. In a prospective study, 117 subjects undergoing allogeneic marrow transplantation were followed for 120 days with weekly CMV blood cultures, with day 35 bronchoalveolar lavage CMV cultures, with weekly CMV P-PCR, and with clinical follow-up for an additional 1-2 years. Despite preemptive ganciclovir, CMV disease occurred in 9% of subjects, with a median time of onset of 176 days. Quantitative CMV P-PCR was associated with the late development of CMV disease (P = .01). Of 43 subjects with positive P-PCR results, 23% developed CMV disease, but no disease occurred in the 74 subjects with negative P-PCR (P < .001), despite the fact that 22% had CMV isolated from lung lavage fluid and 32% had CMV isolated from blood.     

Fulminant, CMV-associated, haemophagocytic syndrome following unrelated bone marrow transplantation

We report a case of haemophagocytic syndrome (HPS) occurring after allogeneic bone marrow transplantation (BMT) for acute promyelocytic leukaemia (APL) in a patient in fourth complete remission (CR). Anti-cytomegalovirus (CMV) antibody (Ab) was negative in this patient before BMT. BMT was performed from an HLA-identical unrelated donor who was positive for CMV Ab. After bone marrow engraftment and haematological recovery, severe acute graft-versus-host disease (GVHD) developed. This patient was treated with methylprednisolone in addition to cyclosporin A (CsA). Acute GVHD showed partial improvement, but CMV antigenaemia was observed. Despite administration of gancyclovir and immunoglobulin, CMV antigenaemia showed no improvement and HPS developed. As no other infections or malignancies were observed, we suspect that CMV infection was the trigger for development of HPS.     

Elevated serum cytokines are associated with cytomegalovirus infection and disease in bone marrow transplant recipients

To assess the relationship between serum cytokines and cytomegalovirus (CMV) reactivation, 75 allogeneic bone marrow transplant patients underwent weekly measurements of interleukin (IL)-6, IL-8, and tumor necrosis factor (TNF)-alpha, CMV blood cultures, and antigenemia tests. Of the patients, 44 (58.7%) developed CMV infection, and 19 (25.3%) developed clinical CMV disease. The mean maximum levels of all three cytokines were significantly increased in patients with CMV infection compared with levels in those without. Maximum levels of IL-6 were significantly higher in patients with active CMV disease than in those who did not develop CMV disease (281.2+/-85.5 vs. 95.7+/-15.0 pg/mL; P=.034). Levels of IL-8 and TNF-alpha were also elevated in patients who developed active disease. In a multivariate logistic regression model, IL-6 levels were independently associated with CMV disease (odds ratio=1.70 per 100-pg/mL increase in IL-6; P=.009). Cytokines may play an important role in the pathogenesis of CMV after bone marrow transplantation and may be a useful predictor for CMV.     

Lungs are a major organ site of cytomegalovirus latency and recurrence

Recurrence of infectious virus from the latent viral genomes is the initiating event in the pathogenesis of cytomegalovirus (CMV) disease during states of immunodeficiency. Interstitial pneumonia is a frequent manifestation of posttransplantation CMV disease, in particular after bone marrow transplantation and heart and lung transplantations. Recurrence can occur within the transplant derived from a latent infected donor as well as within latently infected organs of the transplant recipient. The reason for a predilection of the lungs as a site of CMV pathology is so far unknown. In a murine model of CMV latency, the lungs were identified as an authentic site of latent infection, since the viral genome remained detectable in lung tissue even after it was cleared to an undetectable level in blood and bone marrow. A comparison between the lungs and the spleen, the previously most thoroughly investigated site of murine CMV latency, revealed a 10-fold-higher burden of latent viral genome for the lungs. Most important, the organ-specific risk of in vivo recurrence was found to correlate with the organ-specific viral genomic load. This new finding thus characterizes the lungs as a high-risk organ for CMV recurrence, and this fact may explain in part why interstitial pneumonia is a frequent manifestation of recurrent CMV infection.     

Cloning and bacterial expression of sesquiterpene cyclase, a key branch point enzyme for the synthesis of sesquiterpenoid phytoalexin capsidiol in UV-challenged leaves of Capsicum annuum

The optimal prophylactic strategy for cytomegalovirus (CMV) disease after allogeneic hematopoietic stem cell transplantation has not yet been established. The aim of this study was to analyze our single-center experience with a uniform protocol of CMV antigenemia-guided pre-emptive treatment with ganciclovir (GCV) after allografting. Fifty-two consecutive adult patients, 48 of them transplanted from HLA-identical matched related donors were included. T cell-depleted marrow or peripheral blood were used in 21 cases. After engraftment, weekly blood samples were tested for CMV pp65 antigenemia and viremia (conventional cultures) until day +100. GCV was started if CMV antigenemia and/or CMV viremia were detected. CMV infection (CMV-I) was found in 19 patients (37%). Seven patients suffered from CMV disease (CMV-D), three colitis and four pneumonias. There was one death directly related to CMV-D and three further cases died from refractory GVHD with CMV-D. Only one patient developed CMV pneumonia without any previous positive antigenemia and/or viremia. Multivariate analysis identified grades II-IV acute GVHD (P = 0.02) and peripheral blood stem cell transplantation (P = 0.03) to be risk factors for developing CMV-I. In conclusion, this monitoring protocol allowed early treatment of CMV-I without progression to CMV-D. Pre-emptive therapy had the additional advantage of avoiding GCV administration in most of our allograft recipients.     

Thrombotic microangiopathy in association with cytomegalovirus infection in a renal transplant patient: a new treatment strategy

BACKGROUND: Cytomegalovirus (CMV) associated with thrombotic microangiopathy (TMA) in transplant patients has not been extensively described. This case illustrates an association between CMV and TMA in a transplant patient with resolution of the latter after treatment of the CMV. METHODS AND RESULTS: At 6 weeks after renal transplantation, a 57-year-old woman presented with TMA. Cyclosporine was discontinued, and plasmapheresis was started. However, the patient continued to deteriorate and developed CMV pneumonitis. Plasmapheresis was discontinued, and intravenous ganciclovir was initiated. Both the TMA and the CMV resolved after initiation of the ganciclovir. CONCLUSION: This case identifies another potential etiological factor in the development of TMA after renal transplantation. It is the first reported case of TMA being cured with treatment of CMV.     

Experimental syringomyelia: late ultrastructural changes of spinal cord tissue and magnetic resonance imaging evaluation

Seroprevalence for CMV varies from 70% in the general population to more than 90% in HIV infected patients. Immunodepression whatever its origin, either post therapeutic as in transplant recipients, or induced by HIV, leads to the reactivation of this virus, present in a latent form in the host. In CMV-seronegative patients, the main prevention is based on donor matching before a graft (graft of seronegative donor) and on the use of seronegative blood products or deleukocyted blood. Since the availability of efficient strategies of prophylaxis (before infection) or of early treatment (pre-emptive therapy), CMV disease is now infrequent in most transplantation centers. A real prophylaxis with ganciclovir is usually selected in high risk patients (lung, bone marrow transplants in case of a CMV seropositive recipient or seronegative but with a seropositive donor). It has replaced in most centers aciclovir that has only a modest efficacy. A pre-emptive therapy by ganciclovir is proposed in case of lower risk of CMV disease (kidney, liver or heart transplants) or if the local virology laboratory provides sensitive virological markers to detect the first signs of CMV reactivation. Besides viremia or pp65 antigenemia, currently used to initiate a pre-emptive therapy, the standardisation of other virological markers such as leukocytic or plasmatic PCR is in progress. The prophylaxis of CMV disease in less developed for HIV infected patients. Immunosuppression, continuously progressing in absence of antiretroviral agents, requires a continuous prophylaxis for months or years, treatment that is difficult to propose at the present time considering the modest activity of oral ganciclovir, the only oral agent available. Future progresses in this field will be obtained when a sensitive and reproductible CMV marker will allow to identify the patients at highest risk of CMV disease, and with new anti-CMV agents having a good oral bioavailability.     

Bone marrow failure by cytomegalovirus is associated with an in vivo deficiency in the expression of essential stromal hemopoietin genes

Bone marrow (BM) failure associated with cytomegalovirus (CMV) infection is a feared complication after clinical BM transplantation. Experiments in long-term BM cultures have indicated that BM stromal cells (BMSC) are targets of productive CMV infection, but an in situ infection of BM stroma remained to be documented, and the pathomechanism is open to question. Here we describe a murine in vivo model of lethal CMV aplastic anemia (CMV-AA). The reconstitution of hematopoietic progenitor cells expressing stem cell factor (SCF) receptor was found to be defective in CMV-AA. While murine CMV replication in permissive parenchymal tissues is cytolytic, the hematopoietic cord was found to be a site of very limited virus production with foci of reticular BMSC expressing the intranuclear viral IE1 protein, but with only a few BMSC positive for viral genome in the in situ hybridization. XX-XY BM chimeras were established in order to quantitate Y-chromosome-tagged BMSC by a PCR specific for the male-sex-determining gene Tdy. This approach revealed that murine CMV infection is not associated with a significant loss of BMSC. Despite the physical integrity of the stromal network, the functional integrity of the stroma was impaired. While housekeeping genes were expressed normally in BMSC of infected mice, the expression of genes encoding the essential hemopoietins SCF, granulocyte colony-stimulating factor, and interleukin-6 was markedly reduced. In conclusion, the mechanism of BM failure is not a stromal lesion but an insufficient stromal function. These findings explain CMV-AA as a manifestation of multiple hemopoietin deficiency.     

Preemptive CD8 T-cell immunotherapy of acute cytomegalovirus infection prevents lethal disease, limits the burden of latent viral genomes, and reduces the risk of virus recurrence

In the immunocompetent host, primary cytomegalovirus (CMV) infection is resolved by the immune response without causing overt disease. The viral genome, however, is not cleared but is maintained in a latent state that entails a risk of virus recurrence and consequent organ disease. By using murine CMV as a model, we have shown previously that multiple organs harbor latent CMV and that reactivation occurs with an incidence that is determined by the viral DNA load in the respective organ (M. J. Reddehase, M. Balthesen, M. Rapp, S. Jonjic, I. Pavic, and U. H. Koszinowski. J. Exp. Med. 179:185-193, 1994). This predicts that a therapeutic intervention capable of limiting the load of latent viral genome should also reduce the risk of virus recurrence. Here we demonstrate the benefits and the limits of a preemptive CD8 T-cell immunotherapy of CMV infection in the immunocompromised bone marrow transplantation recipient. Antiviral CD8 T cells prevented CMV disease and accelerated the resolution of productive infection. The therapy also resulted in a lower load of latent CMV DNA in organs and consequently reduced the incidence of recurrence. The data thus provide a further supporting argument for clinical trials of preemptive cytoimmunotherapy of human CMV disease with CD8 T cells. However, CD8 T cells failed to clear the viral DNA. The therapy-susceptible portion of the DNA load differed between organs and was highest in the lungs. The existence of an invariant, therapy-resistant load suggests a role for immune system evasion mechanisms in the establishment of CMV latency.     

Bispectral EEG index during nitrous oxide administration

Recent reports suggest an increased incidence of cytomegalovirus (CMV) infection in recipients of unrelated donor (UD) bone marrow transplantation (BMT). In this study we have collated the incidence of CMV infection and disease in sequential UD (n = 119) and related donor (RD; n = 79) BMT performed in a single institution over a 7-year period. Low-risk patients (CMV seronegative recipient and donor) accounted for 51% of UD BMT (n = 61) and 62% of RD BMT (n=49), with CMV excretion documented in one RD BMT only. The remaining high-risk patients received identical prophylaxis regimens with aciclovir and intravenous immunoglobulin (IVIG). Two groups consisting of 58 UD BMT (median age 9.0 years, range 0.7-45.3 years) and 30 RD BMT (median age 13.6 years. range 1.6-47.6 years) were analysed. CMV reactivation/re-infection was documented in 15 UD BMT (26%) and 10 RD BMT (33%) (P = 0.72), and CMV disease in four UD BMT (8%) and four RD BMT (13%) (P = 0.533). In this series the risk of CMV excretion and disease following UD BMT was similar to that following RD BMT.     

Diagnostic value of Western blotting in carbohydrate-deficient glycoprotein syndrome

Cytomegalovirus (CMV) infection has been associated with graft rejection in solid organ transplantation and with graft-versus-host disease in marrow transplantation. We hypothesized that CMV-infected endothelial cells play an important role in the rejection process, because of their strategic localization at the interface with the host immune system and their ability to modulate T cell function. To study the effect of CMV infection on cell-mediated cytotoxicity against endothelial cells, peripheral blood mononuclear cells (MNC) were incubated with CMV-infected umbilical vein endothelial cells (CMV-UVEC) or mock-infected controls (M-UVEC) and lysis measured by [3H]leucine release. MNC lysed only CMV-UVEC to a maximum of 23% at E:T 20:1. Lysis was not affected by CD3+ cell depletion, but was abolished by CD16+ cell depletion, indicating that NK cells were the effectors. The kinetics of the NK-mediated lysis of CMV-UVEC paralleled the time course of CMV antigen expression. Furthermore, ganciclovir treatment of CMV-UVEC cultures decreased both specific antigen synthesis and NK-mediated lysis. This indicated that NK might recognize either a viral antigen or a cellular antigen modulated by CMV infection. Treatment of CMV-UVEC with F(ab)2 fragments of human polyclonal anti-CMV antibodies failed to inhibit NK cytotoxicity. In contrast, F(ab)2 fragments of MB40.5, a murine MAb reactive with a conserved epitope on the human MHC class I, significantly decreased lysis, proving that NK lysis of CMV-UVEC is an MHC class I-dependent function. To determine whether CMV-UVEC lysis was dependent solely on upregulation of MHC class I, MNC were incubated with CMV-UVEC mixed with uninfected UVEC. There was no competition for NK-target recognition sites, indicating that NK lysis required an interaction with an MHC class I antigen modified by viral infection. Antibodies against IFN-alpha or -beta did not block NK cytotoxicity against CMV-UVEC. Our findings provide a working frame for further evaluation of cellular immune responses to CMV infection.     

Gastric graft-versus-host disease: a blinded histologic study

Acute graft-versus-host disease (GvHD) of the upper gastrointestinal (GI) tract is common after allogeneic bone marrow transplantation (BMT). However, diagnosis cannot be made on clinical presentation and endoscopic findings alone, because these are nonspecific, and histologic confirmation is often desirable. The diagnosis of gastric GvHD is often based on subtle findings with considerable potential for variability in interpretation. Evaluation of the reproducibility of diagnosis and recognition of histologic features of gastric GvHD was based on blinded review of 56 gastric biopsies (24 from patients with allogeneic BMT or unrelated umbilical cord blood transplantation and 32 control biopsies from patients who did not undergo BMT, of whom eight had active GI cytomegalovirus [CMV] infection). Histologic criteria for GvHD were apoptosis and gland destruction, sparse inflammatory infiltrate, and granular eosinophilic debris in dilated glands. Seventeen patients (22 biopsies) were judged to have clinical GvHD on the basis of skin or liver involvement and GI symptoms without other known cause. Eighteen of these 22 gastric biopsies were classified as GvHD by at least two of the three pathologists on initial review. Blinded histologic diagnosis of GvHD had a positive predictive value of 69%, a sensitivity of 82%, and specificity of 76%. False-positive results occurred in CMV gastritis, human immunodeficiency virus (HIV) infection, primary immunodeficiency, and after renal transplantation. Of individual features, granular debris in glands was a specific (94% specificity), but insensitive (41% sensitivity) marker for GvHD. Distinction between GvHD and CMV infection can be difficult, and GvHD can be confused with changes seen in HIV infection and other immunodeficiency states.     

Seroconversion to human herpesvirus 6 following liver transplantation is a marker of cytomegalovirus disease

Human herpesvirus 6 (HHV-6) infection is common after transplantation; HHV-6 is known to interact with other viruses and induce immunosuppression. Whether HHV-6 plays a role in the occurrence of cytomegalovirus (CMV) infection after transplantation was investigated. In a cohort of 247 liver transplant recipients, HHV-6 seroconversion was identified as a significant risk factor for development of symptomatic CMV infection (P < .001), including CMV organ involvement (P < .001), even in the presence of the other significant risk factors: D+/R- CMV serologic status (P < .001) or use of OKT3 after transplantation (P = .002). Subgroup analysis indicated that HHV-6 seroconversion was significantly associated with symptomatic CMV infection in the D+/R+ but not in the D+/R- CMV serologic group (P < .001 and P = .11, respectively). These results indicate that HHV-6 seroconversion is a marker for CMV disease after transplantation and suggest that additional studies using more sensitive diagnostic techniques are warranted to determine the relationship between HHV-6 and CMV infection after transplantation.     

VS--a new computer program for detailed offline analysis of visual-spatial perception

The early belief that CMV infection is lacking any obvious clinical or pathological feature which would permit its recognition (19) was followed by a centennial effort to delineate the genuine clinical picture of the disease, until it became evident that infections with this virus are resulting in a wide range of syndromes (6) correlated with the age (70) and/or the immune status of the host (75), rather than causing a single morbid entity. Even a given syndrome may yield various manifestations (39). Transition of one CMV-induced syndrome to another (61), and the concomitance of two different clinical aspects at distinct body sites, as well as the concurrent evolution of a localized CMV process and systemic CMV illness in the same host, have also been reported (36). Certain organ syndromes appear to be frequently associated with transplantation e.g. interstitial pneumonitis following allogeneic bone marrow grafting, or with a severely immunocompromised state, e.g. CMV retinis in AIDS patients. Maximal therapeutical immunosuppression appears to exagerate the clinical symptomatology of CMV infection, and in AIDS patients the concomitant CMV disease attains epidemic proportions and a dramatic, constantly fatal course (18). Conversely, intercurrent CMV infections may constitute a terminal lethal complication of AIDS.     

Sequential respiratory syncytial virus and cytomegalovirus pneumonia following bone marrow transplantation

A 6-month-old child with familial hemophagocytic lymphohistiocytosis (FHL) experienced early sequential pneumonia due to respiratory syncytial virus (RSV) and cytomegalovirus (CMV) following bone marrow transplantation (BMT). The patient was deficient in natural killer (NK) cell activity (as found frequently in patients with FHL), and this risk factor may have played a major role in the concomitant infection by the two viral pathogens. Rapid diagnostic methods for both viruses are essential and early specific treatment may serve to ameliorate RSV- and CMV-induced lung injury in these life-threatening infections.     

Diagnosis of cytomegalovirus infections by shell vial assay and conventional cell culture during antiviral prophylaxis

A total of 3,552 specimens for conventional cytomegalovirus (CMV) culture and shell vial assay for CMV immediate-early antigen were obtained during a prospective randomized trial for prophylaxis of CMV disease after liver transplantation. Prophylaxis with ganciclovir for 2 weeks and then high-dose acyclovir for 2.5 months was compared with high-dose acyclovir alone for 3 months. During the first 12 weeks after transplantation, when the patients were on prophylaxis, there were significantly more clinical samples positive by the shell vial assay and negative by standard culture in comparison with the number of samples obtained from weeks 13 to 24, after prophylaxis was discontinued, that were positive by the shell vial assay and negative by standard culture. In contrast, significantly fewer samples were positive by both the shell vial assay and standard culture during the first 12 weeks compared with the number obtained 13 to 24 weeks after transplantation that were positive by both methods. Samples positive by the shell vial assay only were obtained significantly more frequently from patients with asymptomatic than symptomatic CMV infections, while samples positive by both methods were obtained significantly more often from patients with symptomatic CMV infection. It was concluded that antiviral prophylaxis with high-dose acyclovir or ganciclovir and then high-dose acyclovir and asymptomatic CMV infection are associated with a decrease in the level of CMV isolation by standard cell culture in comparison with that by the shell vial assay.     

Comparison of PCR and pp65 antigenemia assay with quantitative shell vial culture for detection of cytomegalovirus in blood leukocytes from solid-organ transplant recipients

This study compared PCR and an assay for cytomegalovirus (CMV) pp65 antigenemia (CMV-vue; INCSTAR Corp.) with a quantitative shell vial culture (QSVC) technique for the detection of CMV in serial blood specimens from 46 solid-organ transplant recipients. In a comparison based on 535 specimens tested by PCR and QSVC, CMV was detected by PCR in 41 and by QSVC in 37 of 43 recipients at risk of CMV infection. The mean number of days after transplantation of initial detection of CMV was 29.9 for PCR and 34.0 for QSVC (P = 0.01). The antigenemia assay was performed on 395 specimens, including 304 of those also tested by PCR. In these specimens, CMV was detected by the antigenemia assay, QSVC, and PCR in 30, 32, and 35 (respectively) of 38 patients at risk, with no statistically significant difference in the time to detection. Each of the assays detected CMV in similar proportions of patients with and without clinically significant CMV infection. PCR stayed positive longer after transplantation than the other assays but frequently returned to negative when more than 6 months had elapsed after transplantation. The antigenemia assay and PCR stayed positive longer after institution of antiviral therapy than QSVC. PCR can provide highly sensitive detection of CMV viremia, but a PCR assay for CMV is not yet available in kit form. The pp65 antigenemia assay and shell vial culture are quantifiable and comparable in sensitivity. Either is recommended for rapid detection of CMV in blood specimens from solid-organ transplant recipients.     

Immunization of pigs against Streptococcus suis serotype 2 infection using a live avirulent strain

BACKGROUND: To reduce the mortality rate associated with liver transplantation, it is important to identify the risk factors for increased mortality among liver transplant recipients. It has been suggested that cytomegalovirus (CMV) infection is one such risk factor, but no studies have examined mortality rates associated with the CMV serologic status of the donor and recipient by using multivariate techniques. OBJECTIVE: To study the effect of CMV on 1-year mortality rates in orthotopic liver transplant recipients. DESIGN: Intention-to-treat analysis of a cohort. PATIENTS: 146 liver transplant recipients who were enrolled in a multicenter, randomized, placebo-controlled intervention trial. SETTING: Four university-affiliated transplantation centers. RESULTS: 1-year mortality rates for the four strata of donor and recipient CMV serologic status before transplantation were as follows: seronegative donor and recipient, 11%; seronegative donor and seropositive recipient, 22%; seropositive donor and recipient, 30%; and seropositive donor and seronegative recipient, 44% (P = 0.0091). Multivariate analysis using a time-dependent Cox proportional hazards model showed that retransplantation (relative risk, 4.6 [95% CI, 1.9 to 10.7]; P < 0.001); total number of units of blood products administered during transplantation (relative risk, 1.006 per unit [CI, 1.003 to 1.010]; P < 0.001); and presence of CMV disease (relative risk, 3.9 [CI, 1.8 to 8.5]; P < 0.001), invasive fungal disease (relative risk, 3.3 [CI, 1.5 to 7.1]; P = 0.0020), and bacteremia (relative risk, 2.5 [CI, 1.2 to 5.2]; P = 0.0136) were independently associated with higher mortality rates. If post-transplantation variables that were highly correlated with donor and recipient CMV serologic status were restricted from the model, donor and recipient CMV serologic status was the only pretransplantation variable independently associated with higher mortality rates (P = 0.002). CONCLUSION: Donor and recipient CMV serologic status is a significant pretransplantation determinant for death in liver transplant recipients.