methods for the reduction of transfusion-transmitted cytomegalovirus infection: filtration versus...

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Methods for the reduction of transfusion-transmitted cytomegalovirus infection: filtration versus the use of seronegative donor units C.D. HILLYER, R.K. EMMENS, M. ZAGO-NOVARETTI, AND E.M. BERKMAN TRANSFUSION-TRANSMKED CytOI"@OvirUS (TT-CMV) infection was first described in 1966, and since that time its prevention has been the focus of considerable atten- ti~n.I-~ TT-CMV has been documented in a wide variety of clinical circumstances and can be the cause of signifi- cant morbidity and mortal it^.^-^ While the incidence of some other transfusion-transmittedviral infections (hepa- titis B, hepatitis C, and human immunodeficiency virus) has been significantly reduced by the predonation screen- ing interview and by postdonation serologic testing, TT- CMV cannot be reduced by these measures, because patient history cannot discriminate CMV carriers from noncarriers and antibody screening cannot discriminate infectious units from noninfectious. Eliminating all CMV- seropositive donors to prevent TT-CMV would devastate the blood supply, as the prevalence of antibody to CMV ranges from 60 to 80 percent. Thus, traditional practice has by necessity relied upon the use of a small percent- age of CMV-seronegative units for a few, select patients. Recent data however, suggest that white cell (WBC) re- duction is effective in preventing TT-CMV and therefore may be an easy way to provide "CMV-safe" units to a larger, and rapidly growing, population of patients. In this review, we describe the results of transfusing CMV- seronegative blood versus saline-washed, frozen and deglycerolized, and filtered WBC-reduced components, and we discuss the efficacy of these manipulations in reducing TI'-CMV. CMV Infection Human CMV is a ubiquitous, DNA-containing herpes virus.7 The risk of CMV infection increases with age, lower socioeconomic status, crowded living conditions, Abbreviations:CMV = cytomegalovirus; EM =enzyme immu- nopssey; IHA =indirecthemagglutination (essay); LA = passive latex agglutination; RBC(s) = red cell(s); 'IT-CMV = transfusion-trans- mitted CMV; WBC(s) = white cell(s). From the Departments of Pathology and Medicine and Emory Uni- versity Hospital Blood Bank, Emory University School of Medicine, Atlanta, Georgia; and Division of Hematology/Oncology. Department of Medicine and the New England Medical Center Blood Bank, Tufts University School of Medicine, Boston, Massachusetts. Received for publication February 23, 1993; revision received No- vember I, 1993, and accepted January 19. 1994. and poor hygiene.* The morbidity and/or mortality of the infected host varies, depending on host immune status, underlying disease, route of infection, and size of the viral inoculum. After primary infection, the CMV genome is incorporated into the host DNA, producing latent infec- tion. The infection may then remain latent indefinitely or may become reactivated. While primary infection generally results in more severe clinical illness, reacti- vation of latent infection is the major problem in im- munocompromised patients.8Passenger WBCs have been proposed as the site of latency and the cause of CMV transmission in transfused components. In fact, less than 0.2 percent of circulating WBCs in CMV-seropositive blood donors are estimated to be latently infected? Other cells, including polymorphonuclear neutrophils, mono- nuclear cells, and CD34+progenitor cells, have been in- fected in vitro; however, direct evidence of the in vivo site of latency is still lacking. CMV Infection and Transfusion The association of CMV infection with blood trans- fusion is well known. Transfused red cells (RBCs), plate- let concentrates, and granulocyte concentrates have all been implicated in TT-CMV, while fresh-frozen plasma and cryoprecipitate have not been reported to cause CMV transmission.IO Transfusion of unscreened cellular com- ponents leads to a TT-CMV incidence of approximately 30 percent (range, 10-70%) in seronegative recipients, as determined by seroconversion (fourfold rise in IgG antibody titer) and/or viral isolation. The risk of acquir- ing TT-CMV increases as both the number of components transfused"J2 and the quantity of transfused WBCs in- crease. A storage time of less than 48 hours prior to blood component use has also been proposed as a risk factor for the development of TT-CMV.I3 Patients at Risk for TT-CMV Seronegative patients at risk for developing signifi- cant morbidity from CMV include pregnant women, neonatal infants (especially those with low birth weight [<1200 g]),14-16 patients with leukemiaI7 or beta-thal- a~semia,'**'~ and others who are immunocompromised 929

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Methods for the reduction of transfusion-transmitted cytomegalovirus infection: filtration versus the use

of seronegative donor units

C.D. HILLYER, R.K. EMMENS, M. ZAGO-NOVARETTI, AND E.M. BERKMAN

TRANSFUSION-TRANSMKED CytOI"@OvirUS (TT-CMV) infection was first described in 1966, and since that time its prevention has been the focus of considerable atten- t i ~ n . I - ~ TT-CMV has been documented in a wide variety of clinical circumstances and can be the cause of signifi- cant morbidity and mortal it^.^-^ While the incidence of some other transfusion-transmitted viral infections (hepa- titis B, hepatitis C, and human immunodeficiency virus) has been significantly reduced by the predonation screen- ing interview and by postdonation serologic testing, TT- CMV cannot be reduced by these measures, because patient history cannot discriminate CMV carriers from noncarriers and antibody screening cannot discriminate infectious units from noninfectious. Eliminating all CMV- seropositive donors to prevent TT-CMV would devastate the blood supply, as the prevalence of antibody to CMV ranges from 60 to 80 percent. Thus, traditional practice has by necessity relied upon the use of a small percent- age of CMV-seronegative units for a few, select patients. Recent data however, suggest that white cell (WBC) re- duction is effective in preventing TT-CMV and therefore may be an easy way to provide "CMV-safe" units to a larger, and rapidly growing, population of patients. In this review, we describe the results of transfusing CMV- seronegative blood versus saline-washed, frozen and deglycerolized, and filtered WBC-reduced components, and we discuss the efficacy of these manipulations in reducing TI'-CMV.

CMV Infection Human CMV is a ubiquitous, DNA-containing herpes

virus.7 The risk of CMV infection increases with age, lower socioeconomic status, crowded living conditions,

Abbreviations: CMV = cytomegalovirus; E M =enzyme immu- nopssey; IHA =indirect hemagglutination (essay); LA = passive latex agglutination; RBC(s) = red cell(s); 'IT-CMV = transfusion-trans- mitted CMV; WBC(s) = white cell(s).

From the Departments of Pathology and Medicine and Emory Uni- versity Hospital Blood Bank, Emory University School of Medicine, Atlanta, Georgia; and Division of Hematology/Oncology. Department of Medicine and the New England Medical Center Blood Bank, Tufts University School of Medicine, Boston, Massachusetts.

Received for publication February 23, 1993; revision received No- vember I, 1993, and accepted January 19. 1994.

and poor hygiene.* The morbidity and/or mortality of the infected host varies, depending on host immune status, underlying disease, route of infection, and size of the viral inoculum. After primary infection, the CMV genome is incorporated into the host DNA, producing latent infec- tion. The infection may then remain latent indefinitely or may become reactivated. While primary infection generally results in more severe clinical illness, reacti- vation of latent infection is the major problem in im- munocompromised patients.8 Passenger WBCs have been proposed as the site of latency and the cause of CMV transmission in transfused components. In fact, less than 0.2 percent of circulating WBCs in CMV-seropositive blood donors are estimated to be latently infected? Other cells, including polymorphonuclear neutrophils, mono- nuclear cells, and CD34+ progenitor cells, have been in- fected in vitro; however, direct evidence of the in vivo site of latency is still lacking.

CMV Infection and Transfusion The association of CMV infection with blood trans-

fusion is well known. Transfused red cells (RBCs), plate- let concentrates, and granulocyte concentrates have all been implicated in TT-CMV, while fresh-frozen plasma and cryoprecipitate have not been reported to cause CMV transmission.IO Transfusion of unscreened cellular com- ponents leads to a TT-CMV incidence of approximately 30 percent (range, 10-70%) in seronegative recipients, as determined by seroconversion (fourfold rise in IgG antibody titer) and/or viral isolation. The risk of acquir- ing TT-CMV increases as both the number of components transfused"J2 and the quantity of transfused WBCs in- crease. A storage time of less than 48 hours prior to blood component use has also been proposed as a risk factor for the development of TT-CMV.I3

Patients at Risk for TT-CMV Seronegative patients at risk for developing signifi-

cant morbidity from CMV include pregnant women, neonatal infants (especially those with low birth weight [<1200 g]),14-16 patients with leukemiaI7 or beta-thal- a~semia, '**'~ and others who are immunocompromised

929

930 HILLYER ET AL. TRANSFUSION Vol. 34. No. 1&1994

(e.g., human immunodeficiency virus-positive patients and organ transplant recipients). Indeed, significant CMV-related morbidity and mortality are observed in heart andor lung,20-22 kidney,23 and bone m a r r ~ w ~ ~ - ~ ' transplant recipients.

Other Methods to Prevent or Treat CMV CMV disease remains a severe posttransplantation

complication in both autologous28 and allogeneic bone marrow recipients. Until recently, the mortality from CMV pneumonitis has been extremely high While improved methods for treating CMV infection are available, including intravenous gammaglobulin, CMV IgG-specific immunoglobulin, and preemptive ganciclo- vir and phosfonofonnate, prevention of CMV transmis- sion is still an important goa1.29-33

Availability of CMV-Seronegative Blood Components

The increasing numbers of CMV-seronegative trans- plant candidates, CMV-seronegative transplant recipients, and low-birth-weight seronegative neonatal infants are placing an increasing demand on the transfusion com- munity to supply CMV-safe blood components. Because seropositivity rates are high (up to SO%), it is difficult to provide the needed seronegative components. Until now, testing for CMV antibodies to identify CMV-seronegative units has been the chosen method for preventing TT-CMV. Serum testing for CMV antibodies may be done by indi- rect hemagglutination assay (IHA), anti-complement immunofluorescence, solid-phase fluorescence immuno- assay, enzyme immunoassay (EIA), or passive latex ag- glutination (LA).34*35 These methods are used to detect either specific IgG or total antibodies (IgG, IgM, and IgA) that remain for the life of the person. In general, these tests have specificities (IHA, 90%; EIA, 95%; LA, 100%) and sensitivities (IHA, 89%; EIA, 93%; LA, 93%) that are comparable to those of anti-complement immunofluo- r e s ~ e n c e . ~ ~ - ~ ~

The majority of United States blood centers use LA or EIA in screening blood units. An IgM assay has been proposed as a better indicator of CMV infectivity, but its value remains ~ n p r o v e d . ~ ~ - ~ ' As the finding of antibody is not a good discriminator of infectivity, donor exclu- sion based upon serologic tests only is therefore less than ideal. In fact, it is estimated that only 2 to 12 percent of donated seropositive units will actually transmit CMV."* Newer methods, including detection of CMV nucleic acid by polymerase chain reaction in peripheral leukocytes and CMV antigen testing, may be sensitive and rapid techniques for detection of units capable of transmitting CMV.43 Results of studies using polymerase chain reac- tion in blood donors have ~ a r i e d . ~ . ~ ~ Thus, these tech- niques also require careful evaluation and study.

Screened, Seronegative Components The indications for and efficacy of screened CMV-

seronegative cellular blood components have recently been reviewed.46 CMV-seronegative components are the standard to which other components and manipulations must be ~ o m p a r e d . ~ ' . ~ ~ In one recent study, CMV- seronegative or unscreened blood components were given to 125 CMV-seronegative recipients of CMV-seronega- tive or -seropositive marrow all0grafts.4~ CMV infection occurred in 18 percent of patients receiving seronegative blood components and in 38 percent of those patients who received unscreened blood components. However, when both the recipient and the donor of bone marrow were CMV seronegative, blood component screening was ef- fective in preventing CMV infections. The use of screened RBCs and platelets does reduce the infection rate to ap- proximately 1 to 3 p e r ~ e n t , 4 ~ * ~ ~ but it does not completely prevent TT-CMV in seronegative recipients. This may be due to the loss of CMV antibodies in donors who were previously infected.

WBC-Reduced Blood Components In 1977, a group of patients undergoing open heart

surgery received either WBC-reduced whole blood (cen- trifugation; reduction, 58%) or unmanipulated whole

In CMV-seronegative recipients of the WBC- reduced components, 1 (12.5%) of 8 patients serocon- verted, in contrast to 4 (67%) of 6 control group patients. This reduction in the incidence of TT-CMV following WBC reduction suggested that the virus is present in WBCs. Today, several more-efficient methods are avail- able to reduce the WBC content of cellular blood units, including washing (RBCs only), freezing and thawing (frozen and deglycerolized), centrifugation, andor filtra- tion. In general, centrifugation is the least effective method of removing WBCs, but it is more efficient when followed by filtration. Saline washing removes approxi- mately 90 percent of the WBCs while frozen and de- glycerolized RBCs have slightly fewer contaminating WBCs. Filtration can remove 99 to 99.9 percent of the WBCs and thus may represent a better alternative to the use of screened seronegative blood (see below). Platelet concentrates have also been WBC reduced by centrifu- gation and, more recently, by filtration. Finally, single- donor platelets prepared by newer cell-separation tech- nologies also result in WBC-reduced components (4 x lo6 WBCskomponent). We review these methods and compare the efficiency of WBC reduction, cellular re- covery, processing time, and cost.

Saline-washed RBCs

Neonatal infants. In one study,51 9 (8%) of 115 neo- natal infants who received unscreened, saline-washed RBCs developed CMV viruria. As all infants and their

TRANSFUSION 1996Vol. 34. No. 10 WBC REDUCTION AND CMV TRANSMISSION 93 1

mothers were CMV seronegative upon entry into the study, this was considered evidence of IT-CMV. Another study?* reported a TT-CMV rate of 16 percent under similar con- ditions. The lack of efficacy (8-16% incidence of TT- CMV) of saline-washed components likely represents insufficient reduction in the number of transfused WBCs. Another study, however, demonstrated a TT-CMV (seroconversion) incidence of 1.3 percent in a popula- tion of neonatal infants receiving saline-washed blood component^.^^ The variable rates of CMV transmission among neonatal intensive care units may be explained by the variations in washing protocols and efficiency of this method for WBC reduction. Still, most authorities do not equate saline-washed RBCs with CMV-sero- negative components for the prevention of TT-CMV.

Adults. The use of saline-washed RBCs to prevent IT- CMV has not been studied in the adult population.

Frozen and deglycerolized RBCs

The process of glycerolization, freezing, thawing, and subsequent deglycerolization results in the reduction of WBCs by 94 to 98 percent. Glycerol is avidly taken up by RBCs but not by WBCs. Formation of intracellular ice crystals during the freezing process ruptures the WBCs forming stromal aggregates. Subsequent washing to re- move the cryoprotectant adds to the WBC reduction.

Neonatal infants. TT-CMV in neonatal populations is reduced by the use of frozen and deglycerolized R B C S . ~ ~ - ~ ~ In this setting, the use of frozen and deglyc- erolized RBCs is practical because of the small amount of blood required for transfusion of neonatal infants. In fact, mean total volumes of transfused RBCs in the above- referenced studies ranged from 131 to 230 mL. It is important to recognize that the use of frozen and deglycer- olized RBCs has been associated with some complica- tions. One report5’ discussed recurrent metabolic acido- sis in an infant who received frozen and deglycerolized

cells, which did not recur when conventionally prepared RBCs were used. In addition, the preparation of frozen and deglycerolized RBCs is time-consuming, and they are therefore quite costly.

Adults. The use of frozen and deglycerolized RBCs has prevented TT-CMV in renal dialysis patient^^^,'^ and bone marrow transplant recipientsm In fact, among the 252 neonatal and adult patients studied in reports refer- enced herein, only 2 (0.8%) seroconverted. This rate is similar to the TT-CMV rate when screened CMV- seronegative blood components are used for transfusion support. Thus, it can be concluded that frozen and deglycerolized RBCs are equivalent to CMV-seronega- tive RBCs for the prevention of TT-CMV. An obvious disadvantage to their use is the cost and time required for processing. Also, as platelets cannot be frozen and thawed, these important components would have to be CMV seronegative.

Filtration or centrifugation and filtration

Neonatal infants. In 1989, a controlled trial in low- birth-weight CMV-seronegative infants born to CMV- seronegative mothers compared the use of filtered and unfiltered RBC components for the prevention of TT- CMV.61 The CMV seroprevalence in the donor popula- tion historically was 46 percent, and, although not directly determined in the units, stability in the donating popula- tion was known. Twenty-one percent (9/42) of the recipi- ents of unscreened, unfiltered blood developed evidence of TT-CMV, whereas 0 percent (0/59) of the neonatal infants receiving unscreened, filtered components did so. The efficacy of filtration in this patient population has recently been confirmed.62 In that study, 22 infants re- ceived an average of 2.9 CMV-seropositive, filtered units, and no seroconversion was noted during the study period.

Adults. There are six report^'^-^^-^' in which WBC- reduced RBC components, prepared by centrifugation

Table 1 . Summary of studies using WBC-reduced transfusion components for the prevention of 77-CMV WBC-reduction method Seroconversion rate

Report Diagnosis RBCs Platelets Number Percentage Verdonck et BMT’ (allogeneic) Filtration Seronegative 011 1 0

BMT’ (autologous) Filtration Seronegative 011 8 0 Murphy et al.” Leukemia Filtration WBC-reducedt 011 1 0

Leu kernia None* WBC-reducedt 4134 12 Leu kernia None* None 219 22

deGraan-Hentzen et aLM Leukemidlymphoma BCRFg Centrifugation 0159 0 Cardiac surgery None* None 10186 12

DeWitte et al.65 BMT (allogeneic) Filtration Centrifugation 011 5 0 Bowden et a1.66 BMT (autologous) Seronegative Centrifugation 0135 0 Bowden el aL6’ BMT (autologous) None* None* 7/30 23

BMT (autologous) Filtration Filtration 011 7 0 Total Filtration 011 66 0

Controls 2311 59 15 Bone marrow transplantation. *Controls.

t By apheresis. 9 Buffy coat removed.

932 HILLYER ET AL. TRANSFUSION Vol. 34. No. IC-1994

and/or filtration, are used for the prevention of TT-CMV. Platelet support was with CMV-seronegative components or platelets made WBC-reduced by apheresis. These re- ports are summarized in Table 1. Despite the different combinations of components used by patients who re- ceived WBC-reduced, or WBC-reduced and seronegative components, there was no evidence of CMV disease in any recipients (Oh66 patients). The control groups stud- ied had a 15-percent incidence of ‘IT-CMV (23/159). The patients included in these studies were heavily transfused, had hematologic diseases, or were undergoing bone marrow transplantation. Thus, to date, the evidence is compelling that filtration with 3 log,, reduction filters is at least equivalent to the use of CMV-seronegative blood components in preventing TT-CMV. The use of WBC- reduced RBCs or platelets in CMV-seronegative patients for the prevention of TT-CMV has recently been re-

Despite a number of studies comparing vari- ous methods of WBC reduction, the degree of WBC re- duction necessary for prevention of TT-CMV infection in susceptible individuals is unknown, nor has the use of “bedside” versus “laboratory” filtration been addressed. The use of third-generation filters in reducing CMV trans- mission is gaining pop~lar i ty .~~

Third-generation WBC-reduction filters utilize ab- sorption rather than pore size to achieve an approximately 3 log,, reduction of contaminating WBCs. A prototype filter made from polyester and capable of 6 log,, WBC reduction has recently been d e s ~ r i b e d . ~ ~ * ~ ~ Nucleic acid amplification by polymerase chain reaction has shown that seropositive individuals have detectable CMV DNA in peripheral WBC preparations.44 However, the speci- ficity of the amplified component has been questioned because of the lack of confirmation by hybridization. This conflicts with data from our laboratory and others4’ us- ing CMV-specific hybridization.

Conclusion The accrued evidence suggests that RBCs and plate-

lets, WBC reduced by filtration (3 log,, reduction), can be considered at least equivalent to CMV-seronegative components in preventing TT-CMV; prospective confir- matory trials are underway. We believe that leukemic and bone marrow transplant patients who receive filtered blood for the prevention of alloimmunization should no longer need screened, seronegative RBC and platelet components. If one chooses to use seronegative units as a primary means of preventing TT-CMV, then filtered blood should be used if seronegative units are in limited

Patients who are seronegative and who will undergo seronegative bone marrow or organ transplantation are at greatest risk for TT-CMV and should receive CMV- safe units. While CMV-seronegative units remain a stan-

supply.

dard for the prevention of TT-CMV, filtered units appear to be equivalent in efficacy and are increasingly being used. Patients who are seronegative and will undergo seropositive bone marrow or organ transplantation are at risk for CMV infection, mostly because of the seropositive graft. After transplantation, some patients will remain seronegative, and these patients should receive filtered or seronegative blood. As it is impossible to predict which patients will remain seronegative, all seronegative trans- plant recipients should receive these specialized compo- nents. Most transfusion recipients are CMV seropositive, and as such are at greatest risk for reactivation of their own latent virus. In this group it is less important to use manipulated or seronegative components, though there is a small risk of a secondary infection with a different CMV strain. The studies reviewed here also show that frozen and deglycerolized RBCs are equivalent to CMV- seronegative RBC components. These components are costly and time-consuming to prepare and their use will not affect transfusion practice.

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References Kaariainen L, Klemola E, Paloheimo J. Rise of cytomegalovi- rus antibodies in an infectious-mononucleosis-like syndrome after transfusion. Br Med J 1966;1:1270-2. Hillyer CD, Snydman DR, Berkrnan EM. The risk of cyto- megalovirus infection in solid organ and bone marrow trans- plant recipients: transfusion of blood products. Transfusion

Meyers JD. Prevention and treatment of cytomegalovirus in- fection. Annu Rev Med 1991;42:179-87. Tegtmeier GE. Transfusion-transmitted cytomegalovirus infec- tions: significance and control. Vox Sang 1986;51(Suppl1):22- 30. Nankervis GA, Kumar ML. Diseases produced by cytomega- loviruses. Med Clin North Am 1978;62:1021-35. Sandler SG, Grumet FC. Posttransfusion cytornegalovirus in- fections. Pediatrics 1982;69:650-3. Mocarski ES Jr. Biology and replication of cytornegalovirus. Transfus Med Rev 1988;2:229-34. Adler SP. Cytomegalovirus and transfusions. Transfus Med Rev 1988;2:235-44. Munoz JF, Sharon N. Detection of human cytomegalovirus and Epstein-Barr virus in peripheral blood mononuclear cells with DNA probes. Lab Med 1990;21:742-5. Bowden R, Sayers M. The risk of transmitting cytomegalovi- rus infection by fresh frozen plasma. Transfusion 1990,30:762- 3. Preiksaitis JK, Brown L, McKenzie M. The risk of cyto- megalovirus infection in seronegative transfusion recipients not receiving exogenous immunosuppression. J Infect Dis

Wilhelm JA, Matter L, Schopfer K. The risk of transmitting cytomegalovirus to patients receiving blood transfusion. J In- fect Dis 1986;154:169-71. Adler SP, McVoy MM. Cytomegalovirus infections in sero- positive patients after transfusion: the effect of red cell stor- age and volume. Transfusion 1989;29:667-71. Yeager AS, Grumet FC, Hafleigh EB, Arvin AM, Bradley JS, Prober CG. Prevention of transfusion-acquired cytomegdovi- rus infection in newborn infants. J Pediatr 1981;98:281-7. Adler SP, Chandrika T, Lawrence L, Bagget J. Cytomegalovi- rus infections in neonates acquired by blood transfusions. Pediatr Infect Dis 1983;2:114-8.

1990;30:659-66.

1988; 157523-9.

TRANSFUSION 1994-Vol. 34. No. 10 WBC REDUCTION AND CMV TRANSMISSION 933

16. Galea G, Urbaniak SJ. The incidence and consequences of cytomegalovirus transmission via blood transfusion to low birth weight, premature infants in north east Scotland. Vox Sang

17. Murphy MF, Grint PC, Hardiman AE, Lister TA, Waters AH. Use of leukocyte-poor blood components to prevent primary cytomegalovirus (CMV) infection in patients with acute leukaemia. Br J Haematol 1988;70253-4.

18. Germenis A, Politis C. Thalassemic patients are at high risk for transfusion-transmitted cytomegalovirus infections. Acta Haematol 1989;82:57-60.

19. Montalembert M, Constagliola DG, Lefrhre JJ, et al. Prevalence of markers for immunodeficiency virus type 1 and 2, human T-lymphotropic virus type 1 , cytomegalovirus, and hepatitis B and C virus in multiply transfused thalassemia patients. Trans- fusion 1992;32:509-12.

20. Dummer JS, White LT, Ho M, et al. Morbidity of cytomegalo- virus infection in recipients of heart or heart-lung transplants who received cyclosporine. J Infect Dis 1985;152:1182-91.

2 1. Wreghitt TG, Hakin M, Gray JJ, Kucia S , Wallwork J, English TA. Cytomegalovirus infections in heart and heart and lung transplant recipients. J Clin Pathol 1988;41:660-7.

22. Dummer JS, Montero CG, GrilXth BP, Hardesty RL, Paradis IL, Ho M. Infections in heart-lung transplant recipients. Trans- plantation 1986;41:725-9.

23. Glenn J. Cytomegalovirus infections following renal transplan- tation. Rev Infect Dis 1981;3:1151-78.

24. Meyers JD, Ljungman P, Fisher LD. Cytomegalovirus excre- tion as a predictor of cytomegalovirus disease after bone mar- row transplantation: importance of cytomegalovirus viremia. J Infect Dis 1990,162:373-80.

25. Meyers JD, Floumoy N, Thomas ED. Risk factors for cytomega- lovirus infection after bone marrow transplantation. J Infect Dis

26. Reusser P. Cytomegalovirus infection and disease after bone marrow transplantation: epidemiology, prevention, and treat- ment. Bone Marrow Transplant 1991 ;7(Suppl 3):52-6.

27. Verdonck LF, de Gast GC, Van Heugten HG, Niewenhuis HK, Dekker AW. Cytomegalovirus infection causes delayed plate- let recovery after bone marrow transplantation. Blood

28. Reusser P, Fisher LD, Buckner CD, Thomas ED, Meyers JD. Cytomegalovirus infection after autologous bone marrow transplantation: occurrence of cytomegalovirus disease and effect on engraftment. Blood 1990;75: 1888-94.

29. Filipovich AH, Peltier MH, Bechtel MK, Dirksen CL, Strauss SA, Englund JA. Circulating cytomegalovirus (CMV) neutral- izing activity in bone marrow transplant recipients: compari- son of passive immunity in a randomized study of four intra- venous IgG products administered to CMV-seronegative patients. Blood 1992;80:2656-60.

30. Bowden RA, Fisher LD, Rogers K, Cays M, Meyers JD. Cyto- megalovirus (CMV)-specific intravenous immunoglobulin for the prevention of primary CMV infection and disease after marrow transplant. J Infect Dis 1991;164:483-7.

31. Atkinson K, Downs K, Golenia M, et al. Prophylactic use of ganciclovir in allogeneic bone marrow transplantation: absence of clinical cytomegalovirus infection. Br J Haematol 199 1 ;79:57- 62.

32. Goodrich JM, Mori M, Gleaves CA, et al. Early treatment with ganciclovir to prevent cytomegalovirus disease after al- logeneic bone marrow transplantation. N Engl J Med

33. Schmidt GM, Horak DA, Niland JC, et al. A randomized con- trolled trial of prophylactic ganciclovir for cytomegalovirus pulmonary infection in recipients of allogeneic bone marrow transplants. N Engl J Med 1991;324:1005-11.

34. Taswell HF, Reisner RK, Rabe DE, Shelley CD, Smith TF. Comparison of three methods for detecting antibody to cyto- megalovirus. Transfusion 1986;26:285-9.

35. Phipps PH, Gregoire L, Rossier E, Perry E. Comparison of five methods of cytomegalovirus antibody screening of blood do- nors. J Clin Microbiol 1983; 18: 1296-300.

1992;62:200-7.

1986;153:478-88.

1991 ;78:844-8.

1991;325;23:1601-7.

36. Adler SP, McVoy M, Biro VG, Britt WJ, Hider P, Marshall D. Detection of cytomegalovirus antibody with latex agglutina- tion. J Clin Microbiol 1985;22:68-70.

37 Beckwith DG, Halstead DC, Alpaugh K, Schweder A, Blount- Fronefield DA, Toth K. Comparison of a latex agglutination test with five other methods for determining the presence of anti- body against cytomegalovirus. J Clin Microbiol 198521 :328- 31.

38. McHugh TM, Casavant CH, Wilber JC. Stites DP. Comparison of six methods for the detection of antibody to cytomegalovi- rus. J Clin Microbiol 1985;22:1014-9.

39. Beneke JS, Tegtmeier GE, Alter HJ, Luetmeyer RB, Solomon R, Bayer WL. Relation of titers of antibodies to CMV in blood donors to the transmission of cytomegalovirus infection. J In- fect Dis 1984;159:883-8.

40. Lamberson HV Jr, McMillian JA, Weiner LB, et al. Prevention of transfusion-associated cytomegalovirus (CMV) infection in neonates by screening blood donors for IgM to CMV. J Infect Dis 1988;157:820-3.

41. McVoy MA, Adler SP. Immunologic evidence for frequent age- related cytomegalovirus reactivation in seropositive immuno- competent individuals. J Infect Dis 1989; 160: 1 - 10.

42. Slichter SJ. Transfusion and bone marrow transplantation. Transfus Med Rev 1988;2: 1 - 17.

43. Boeckh M, Bowden RA, Goodrich JM, Pettinger M, Meyers JD. Cytomegalovirus antigen detection in peripheral blood leukocytes after allogeneic marrow transplantation. Blood

44. Bevan IS, Daw RA, Day PJ, Ala FA, Walker MR. Polymerase chain reaction for the detection of human cytomegalovirus infection in a blood donor population. Br J Haematol

45. Bitsch A, Kirchner H, Dupke R, Bein G. Failure to detect hu- man cytomegalovirus DNA in peripheral blood leukocytes of healthy blood donors by the polymerase chain reaction. Trans- fusion 1992;32:612-7.

46. Preiksaitis J. Indications for the use of cytomegalovirus- seronegative blood products. Transfus Med Rev 1991 ;5: 1-1 7.

47. Sererat MN, Schifano JV, Lau P, et al. Evaluation of cytomega- lovirus (CMV) antibody screening tests for blood donors. Am J Clin Pathol 1986;86:523-6.

48. Logan S . Barbara J, Kovar I. Cytomegalovirus screened blood for neonatal intensive care units. Arch Dis Child 1988;63:753-5.

49. Miller WJ, McCullough J, Balfour HH, et al. Prevention of cytomegalovirus infection following bone marrow transplan- tation: a randomized trial of blood product screening. Bone Marrow Transplant 1991;7:227-34.

50. Lang DJ, Eben PA, Rodgers BM, Boggess HP. Rixse RS. Re- duction of postperfusion cytomegalovirus-infections following the use of leukocyte depleted blood. Transfusion 1977;17:391-5.

5 1. Brady MT, Demmler GJ, Seavy D, et al. Method of blood pro- cessing affects the prevalence of cytomegalovirus excretion in newborn nurseries. Am J Infect Control 1987;15:245-8.

52. Demmler GD, Brady MT, Bijou H, et al. Posttransfusion cyto- megalovirus infection in neonates: role of saline-washed red blood cells. J Pediatr 1986;108:762-5.

53. Luban NL. Williams AE, MacDonald MG, Mikesell GT, Wil- liams KM, Sacher RA. Low incidence of acquired cytomega- lovirus infection in neonates transfused with washed red blood cells. Am J Dis Child 1987;141:416-9.

54. Taylor BJ, Jacobs RF, Baker RL, Moses EB. McSwain BE, Shulman G. Frozen deglycerolyzed blood prevents transfusion- acquired cytomegalovirus infections in neonates. Pediatr In- fect Dis 1986;5:188-91.

55. Kim HC, Spitzer AR, Plotkin S . The role of frozen-thawed- washed red blood cells (FTW-RBC) in preventing transfusion acquired CMV infection (TA-CMV) in the neonate. Transfu- sion 1985;25:472.

56. Simon TL, Johnson JD, Koffler H, et al. Impact of previously frozen deglycerolized red blood cells on cytomegalovirus transmission to newborn infants. PlasmaTher Transfus Techno1 1987;8:51.

1992;80: 1358-64.

1991 ;78:94-9.

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57.

58

59

60

61

62

Grifin MP, O’Shea M, Brazy JE, et al. Cytomegalovirus infec- tion in a neonatal intensive care unit. Blood transfusion prac- tices and incidence of infection. Am J Dis Child 1988; 142: 1 188- 93. Betts RF, Cestero RVM, Freeman RB, Douglas RG Jr. Epide- miology of cytomegalovirus infection in end stage renal dis- ease. J Med Virol 1979;4:89-96. Tolkoff-Rubin NA, Rubin RH, Keller EE, Baker GP, Stewart JA, Hirsch MS. Cytomegalovirus infection in dialysis patients and personnel. Ann Intern Med 1978;89:625-8. Kim HC, Cowan J, Auble B, Dorfman M, August CS. Preven- tion of post bone marrow transplantation cytomegalovirus in- fection (CMVI) with the use of frozen-thawed-washed (FTW) RBC and seronegative single donor platelets (SDP) (abstract). Transfusion 1986;26:565. Gilbert GL, Hayes K, Hudson IL, James J. Prevention of trans- fusion-acquired cytomegalovirus infection in infants by blood filtration to remove leukocytes. Lancet 1989;2: 1228-3 1. Eisenfeld L, Silver H, McLaughlin J, et al. Prevention of trans- fusion-associated cytomegalovirus infection in neonatal pa- tients bv the removal of white cells from blood. Transfusion 1992;32:205-9.

63. Verdonck LF, de Graan-HentzenYC, Dekker AW, Mudde GC, de Gast GC. Cytomegalovirus seronegative platelets and leu- kocyte-poor red blood cells from random donors can prevent primary cytomegalovirus infection after bone marrow trans- plantation. Bone Marrow Transplant 1987;2:73-8.

64. De Graan-Hentzen YCE, Gratama JW, Mudde GC, et al. Pre- vention of primary cytomegalovirus infection in patients with hematologic malignancies by intensive white cell depletion of blood products. Transfusion 1989;29:757-60.

65. De Witte T, Schattenberg A, Van Dijk BA, et al. Prevention of primary cytomegalovirus infection after allogeneic bone mar- row transplantation by using leukocyte-poor random blood products from cytomegalovirus-unscreened blood-bank do- nors. Transplantation 1990;50:964-8.

66. Bowden RA, Slichter SJ, Sayers MH, Mori M, Cays MJ, Meyers JD. Use of leukocyte-depleted platelets and cytomegalo- virus-seronegative red blood cells for prevention of primary cytomegalovirus infection after marrow transplant. Blood I99 I ;79:246-50.

67. Bowden RA, Sayers MH, Cays M, Slichter SJ. The role of blood product filtration in the prevention of transfusion associated cytomegalovirus (CMV) infection after marrow transplant (ab- stract). Transfusion 1989;29(Suppl I):57S:

68. Snyder EL. Clinical use of white cell-poor blood components. Transfusion 1989;29:568-7 1.

69. Rebulla P, Bertolini F, Parravicini A, SirchiaG. Leukocyte-poor blood components; a purer and safer transfusion product for recipients? Transf Medus Rev 1990;4(Suppl 1):19-23.

70. Bowden RA. Cytomegalovirus infections in transplant patients: methods of prevention of primary cytomegalovirus. Transplant

71. Wenz B. Clinical and laboratory precautions that reduce the adverse reactions, alloimmunization, infectivity, and possibly immunomcdulation associated with homologous transfusion. Transfus Med Rev 1990;4(SuppI 1):3-7.

72. Sadoff BJ, Stromberg RR, Miller K, Ngo D, Friedman LI. Ex- perimental 6 log,, white cell-reduction filters for red cells. Transfusion 1992;32: 129-33.

73. Rawal BD, Davis RE, Busch MP, Vyas GN. Dual reduction in the immunologic and infectious complications of transfusion by filtrationhemoval of leukocytes from donor blood soon after collection. Transfus Med Rev 1990;4(Suppl 1):36-41.

ROC 1991;23(S~ppl 3):136-8.

Christopher D. Hillyer, MD, Assistant Director, Emory Univer- sity Hospital Bloud Bank; and Assistant Professor, Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta. GA.

Robert K. Emmens. MD, Resident, Department of Pathology and Laboratory Medicine, Emory University School of Medicine.

Marcia Zago-Novaretti, MD. Research Fellow, Division of He- matology/Oncology. Department of Medicine, New England Medi- cal Center, Tufts University School of Medicine.

Eugene M. Berkman. MD. Professor, Tufts University School of Medicine; and Medical Director, New England Medical Center Blood Bank, Division Hematology/Oncology, Department of Medi- cine, 750 Washington Street. Box 826. Boston. MA. [No reprints available]