Indications for the use of cytomegalovirus-seronegative blood products

Transfusion-transmitted and community-acquired cytomegalovirus infection in seronegative solid organ transplant recipients receiving seronegative donor organs

Solid organ transplant (SOT) recipients who are cytomegalovirus (CMV) seronegative (R-) and receive seronegative donor (D-) organs have a small but currently unquantified risk of both transfusion-transmitted CMV (TT-CMV) and community-acquired CMV (CA-CMV). We retrospectively studied the incidence and clinical symptoms of TT-CMV (infection <1 year posttransplant) and CA-CMV (infection >1 year posttransplant) in a cohort of D-/R- adult and pediatric SOT recipients receiving leukoreduced blood products not screened for CMV seronegativity transplanted at our center between 2000 and 2011. CMV infection was defined as IgG seroconversion or detectable CMV antigenemia/DNAemia. Among 536 consecutive D-/R- recipients, 398 (81.8%) had adequate follow-up, and 231 (58%) received cellular blood products (total: 1626 red blood cell units, 470 platelet units) 30 days pretransplant to 90 days posttransplant. We observed no confirmed TT-CMV cases, but 14 CA-CMV cases (64% symptomatic) were seen. The estimated incidence rate of CA-CMV was higher in children (3.0/100 patient years) than adults (0.46/100 patient years, incident rate ratio of 6.52). The absence of TT-CMV over 11 years suggests neither seronegative blood products nor CMV DNA blood donor screening would provide significant incremental safety when blood is already leukoreduced. D-/R- SOT recipients, particularly children, have a significantly higher and ongoing risk of CA-CMV.

Cytomegalovirus (CMV) seroprevalence in Japanese blood donors and high detection frequency of CMV DNA in elderly donors

BACKGROUND

The current prevalence of cytomegalovirus (CMV) in Japan and the risk of CMV transfusion transmission are unknown in the era of seronegative leukoreduced blood components.

STUDY DESIGN AND METHODS

We measured CMV-specific immunoglobulin (Ig)M and IgG in 2400 samples of whole blood collected from 12 groups of blood donors categorized by sex and age at 10-year intervals from their teens to their 60s. We also tested for CMV DNA using polymerase chain reaction in the cellular fractions of all samples.

RESULTS

We found that 76.6% of blood donors were CMV seropositive. The seroprevalences among donors in their 20s and 30s were 58.3 and 73.3%, respectively. We detected CMV DNA in the cellular fraction of 4.3% of samples from donors in their 60s and in 1.0% of samples from donors younger than 60 years. None of the 562 seronegative samples was DNA positive. Furthermore, 14% of DNA-positive samples also contained DNA in the plasma fraction, and two of five such samples were derived from donors in their 60s. Leukoreduced plasma components derived from donations with CMV DNA in plasma samples also contained a relevant amount of CMV DNA.

CONCLUSION

The seroprevalence of CMV among Japanese blood donors of child-bearing age has not changed over the past 15 years. Latent CMV becomes reactivated more frequently among elderly donors than among younger donors. A proportion of them have free CMV DNA in their plasma fraction, which could not be diminished by leukoreduction. The risk of transfusion-transmitted CMV infection in blood with plasma CMV DNA should be determined.

Why implement universal leukoreduction?

The improvement of transfusion medicine technology is an ongoing process primarily directed at increasing the safety of allogeneic blood component transfusions for recipients. Over the years, relatively little attention had been paid to the leukocytes present in the various blood components. The availability of leukocyte removal (leukoreduction) techniques for blood components is associated with a considerable improvement in various clinical outcomes. These include a reduction in the frequency and severity of febrile transfusion reactions, reduced cytomegalovirus transfusion-transmission risk, the reduced incidence of alloimmune platelet refractoriness, a possible reduction in the risk of transfusion-associated variant Creutzfeldt-Jakob disease transmission, as well as reducing the overall risk of both recipient mortality and organ dysfunction, particularly in cardiac surgery patients and possibly in other categories of patients. Internationally, 19 countries have implemented universal leukocyte reduction (ULR) as part of their blood safety policy. The main reason for not implementing ULR in those countries that have not appears to be primarily concerns over costs. Nonetheless, the available international experience supports the concept that ULR is a process that results in improved safety of allogeneic blood components.

Transfusion-Transmitted Cytomegalovirus: Lessons From a Murine Model

Transfusion-transmitted cytomegalovirus (CMV) infection (TT-CMV) continues to complicate blood transfusion therapy, which can lead to severe morbidity or mortality in immunocompromised or immuno-immature recipients. The biological mechanisms that underlie TT-CMV (eg, viral latency in donor monocytes or stimulatory signals in the transfusion recipient leading to cytomegalovirus reactivation) are difficult to study in humans, but can be addressed in animal models. In this review, we discuss a mouse blood transfusion model, which can be used to investigate these issues as well as to validate methods to prevent TT-CMV in at-risk patients.

Transfusion-transmitted cytomegalovirus (CMV) infections in a murine model: characterization of CMV-infected donor mice

BACKGROUND

Donor and recipient mechanisms that modulate the incidence and severity of transfusion-transmitted cytomegalovirus (TT-CMV) are unclear. The kinetics of murine CMV (MCMV) infection in the peripheral blood of donor mice were investigated to determine the utility of this model for studying TT-CMV.

STUDY DESIGN AND METHODS

BALB/cByJ mice, experimentally infected with Smith strain MCMV, were killed at serial time points up to 28 days after infection. Peritoneal exudate cells (PECs), peripheral blood white blood cells (WBCs), plasma, and marrow were tested for MCMV DNA with quantitative polymerase chain reaction (PCR), replication-competent virus with quantitative culture, and transcription of viral genes with reverse transcription (RT)-PCR targeted at the immediate-early 1 (ie1) gene.

RESULTS

PECs, macrophages infected by MCMV shortly after intraperitoneal inoculation, demonstrated high mean levels of MCMV DNA (10(5)-10(7) genome equivalents [geqs]/10(5) PECs), virus production (10(1)-10(4) infectious virions/10(5) PECs), and ie1 gene transcription, demonstrating productive infection. In contrast, while MCMV loads averaged 10(4) to 10(6) geqs per 10(5) peripheral WBCs, all WBC samples were uniformly negative for MCMV ie1 expression by RT-PCR and for culturable virus, consistent with latent MCMV infection. Plasma and marrow showed lower viral loads than WBCs and PECs and were all negative by culture and RT-PCR analysis.

CONCLUSIONS

Following experimental MCMV infection, murine peripheral blood WBCs appear to be latently infected with virus (MCMV DNA-positive; MCMV RNA-negative; MCMV culture-negative), similar to the latently infected human monocytes in peripheral blood of CMV-seropositive donors. These donor kinetics suggest that the experimental MCMV system can be used to effectively model the mechanisms of TT-CMV infections in humans.

Antimicrobial prophylaxis in allogeneic bone marrow transplantation. Guidelines of the Infectious Diseases Working Party (AGIHO) of the German Society of Haematology and Oncology

Patients undergoing allogeneic stem cell transplantation are at high risk for infection with a variety of pathogens during different phases of the procedure. Bacteria and fungi predominate the first phase until engraftment. During the second phase, from engraftment to about day 100, major infectious problems are caused by fungi and cytomegalovirus. Both pathogens remain important under continued immunosuppression, however, in the late post-transplantation period infections with encapsulated bacteria may become a problem. In this review the Infectious Diseases Working Party of the DGHO gives recommendations for prophylaxis of infections under allogeneic stem cell transplantation with drugs and other measures. The aim of the group was to do this on an evidence-based-medicine rating, if possible.

Is White Blood Cell Reduction Equivalent to Antibody Screening in Preventing Transmission of Cytomegalovirus by Transfusion? A Review of the Literature and Meta-Analysis

The question whether the use of cytomegalovirus (CMV)-seronegative versus white blood cell (WBC)-reduced blood components is equally efficacious in preventing transfusion-acquired CMV infection remains unresolved. A total of 829 recipients of CMV-seronegative components were followed in 11 studies, and a total of 878 recipients of WBC-reduced components were followed in 12 studies. Twelve (1.45%) of 829 recipients of CMV-seronegative components and 24 (2.73%) of 878 recipients of WBC-reduced components developed CMV infection in these studies. Among bone marrow transplant (BMT) recipients, the risk of CMV infection was, respectively, 1.63% (11/674) and 3.01% (21/697). Four of 7 controlled studies of CMV-seronegative components and 1 of 3 controlled studies of WBC-reduced components indicated benefit from these special components compared with CMV-unscreened/non-WBC-reduced components. One of 3 controlled studies indicated benefit from CMV-seronegative components, as compared with WBC-reduced components. Across a subset of studies whose results were integrated in a meta-analysis, CMV-seronegative or WBC-reduced components were virtually equivalent to each other when they were compared with CMV-unscreened/non-WBC-reduced components. CMV-seronegative components were associated with a 93.1% reduction in the risk of CMV infection; WBC-reduced components were associated with a 92.3% reduction in risk (summary odds ratio [OR] = 0.069; 95% confidence interval [CI], 0.037-0.128; P < .05; and summary OR = 0.077; 95% CI, 0.031-0.190; P < .05, respectively). However, across 3 studies that compared CMV-seronegative and WBC-reduced components to each other, CMV-seronegative components were associated with a 58% reduction in risk (summary OR = 0.42; 95% CI, 0.22-0.79; P < .05). Thus, a meta-analysis of the available controlled studies indicates that CMV-seronegative blood components are more efficacious than WBC-reduced blood components in preventing transfusion-acquired CMV infection.

Blood transfusion in newborn

Premature infants are among the most frequently transfused groups of patients, usually receiving red cells. The immaturity of the immune system, its lesser ability to cope with a metabolic load and the presence of maternal antibodies, all complicate the picture. Conservation of blood to minimize losses and the need for replacement transfusion is an important strategy that has already been successful in reducing the need for transfusion on neonatal units. The advent of erythropoietin provides another strategy for reducing the need for transfusion. It is unfortunate that the sickest patients who require the most transfusion poorly respond to erythropoietin. Main concern is the long-term consequences of transfusion. Presently the aim is to minimize transfusion risks and give transfusions only when they are indicated.

CMV and blood transfusions

Among the human herpesviruses, cytomegalovirus (CMV) is the only one that has assumed significant importance in blood transfusion. Transfusion transmission of CMV (TT-CMV) to seronegative immunocompromised patients can lead to lethal CMV disease. Studies over the past 30 years have demonstrated that monocytes latently infected with CMV represent the primary vector for TT-CMV, and that TT-CMV can be largely abrogated by transfusing at-risk patients with either seronegative units or blood filtered to remove white blood cells. However, the small number of cases of breakthrough TT-CMV that follow transfusion of either seronegative or filtered blood still produce morbidity and mortality. These circumstances have motivated ongoing efforts to provide improved protection from TT-CMV, including the use of CMV DNA amplification for blood screening, and pathogen inactivation to sterilise all blood components prior to transfusion.

Practice parameter for the recognition, management, and prevention of adverse consequences of blood transfusion. College of American Pathologists

No Abstract Available

Transfusion associated graft-versus-host disease, cytomegalovirus infection and HLA alloimmunization in neonatal and pediatric patients

Modern transfusion support of pediatric patients requires attention to the necessity to provide specialized or modified blood components to these patients who are often immunocompromised and/or affected by very complex medical and surgical illnesses. In this review we will address three potential complications of transfusion that may require specialized components for their prevention in selected patients namely transfusion-associated graft-versus-host disease, transfusion-transmitted cytomegalovirus infection and HLA alloimmunization, with particular reference to the indications for prevention of these transfusion complications in neonatal and pediatric patients.

Sepsis

OBJECTIVES

To review infection and sepsis in patients with cancer and to provide an overview of controversies and research-based practices of infectious complications and management strategies.

DATA SOURCES

Research studies, review articles, web sites, and consensus documents.

CONCLUSIONS

Traditional assumptions about infection and its optimal management are redefined by research regarding transfusion and catheter-related infections, prophylactic antibiotic administration, use of growth factors, and antimicrobial therapy regimens.

IMPLICATIONS FOR NURSING PRACTICE

Infection is still the most common source of morbidity and mortality among cancer patients. The importance of recognizing high-risk patients, implementing infection prevention practices, and prompt intervention for infection symptoms has been established.

A survey of Canadian neonatal blood transfusion practices

In 1990, the Pediatric Hemotherapy Committee of the American Association of Blood Banks developed and distributed a questionnaire addressing neonatal blood transfusion practices. The same questionnaire was subsequently sent to Canadian university-affiliated hospitals (n = 92). This report describes the results of the Canadian survey. Seventy-two percent (n = 66) of institutions contacted responded. Of these 42% (n = 28) had sufficient experience with neonatal transfusions and provided sufficient data for analysis. Although the majority of stated practices did follow published guidelines, several areas of variability and/or suboptimal practices were identified. With respect to component selection and preparation, suboptimal practices included excessive pretransfusion testing, unnecessary routine washing of RBC concentrates for small-volume transfusions, routine volume reduction of platelet concentrates and the use of suboptimal granulocyte preparations. With respect to transfusion practices, a disturbingly high percentage of respondents indicated that frozen plasma would be given in situations generally considered inappropriate. There was a great deal of variability in the provision of blood components at low risk for CMV, in the use of gamma irradiation and in the platelet count used for prophylactic platelet transfusions. The data collected in this survey provide information concerning practices that require improvement, identify areas where further research is desirable and provide a basis for comparison with current and future neonatal blood transfusion practices.

Transfusion and stem cell support in cancer treatment

Intensification of therapeutic regimens, improved patient survival, and advances in cytokine and cellular therapies have led to increasingly complex requirements for transfusion and stem cell support in cancer treatment. This article focuses on current and evolving issues in red blood cell, platelet, and granulocyte transfusion support, as well as measures to avoid increasingly important complications of transfusion therapy, such as alloimmunization, graft-versus-host disease, cytomegalovirus infection, and immunomodulation. Issues concerning current applications of hematopoietic stem cell transplantation and future prospects also are discussed.

Transfusion therapy for patients critically Ill with cancer

Patients with cancer receive antineoplastic therapy that affect their ability to produce and maintain circulating levels of blood cells at any given time. Frequent and varied transfusion requirements necessitate a highly developed and specialized practice of blood component therapy in cancer care. In this article, the author discusses factors affecting the selection of blood components and the influence that expert critical care nurses can contribute to safe and effective transfusion therapy. Administration of leukocyte-poor or cytomegalovirus-negative erythrocytes, pheresed platelets, and granulocyte transfusions are described.