Transfusion of one unit or more of Rh-positive red blood cells normally causes circulating anti-D antibody to appear 2-6 months later in 80-95% of Rh- persons. We asked whether transplant immunosuppression with cyclosporine and corticosteroids affects Rh immunization. Nineteen Rh- liver, heart, and heart-lung transplant recipients received 3-153 (median: 10) units of Rh+ RBCs at surgery and were tested for anti-D greater than 2 months later. Three patients developed anti-D at 11-15 days; one may have had an unusually rapid primary immune response and two were secondary to previous exposure by pregnancy. None of the other 16 patients had anti-D when tested 2.5-51 months later (13 patients, greater than 11.5 months). This low rate of Rhesus immunization in association with cyclosporine immunosuppression allows greater flexibility in meeting the transfusion needs of Rh- liver and heart transplant patients. Caution is still advised in young females and in patients who may have been previously exposed to Rh+ RBCs by transfusion or by pregnancy prior to the availability of perinatal Rh immune globulin twenty years ago. Other humoral immune responses to some vaccines or infectious agents may also be impaired in transplant patients.

Liver transplant patients frequently require large amounts of blood. The frequency and nature of their red cell (RBC) antibody problems were examined. Records were reviewed in 496 adults and 286 children undergoing 1000 consecutive transplants. Twenty-two percent of adults and 14 percent of children had RBC alloantibodies. Antibodies of potential clinical significance were found before transplant in 6.3 percent of adults and 1.0 percent of children; despite immunosuppression, they appeared 1 to 5 weeks after transplant in an additional 7.5 and 5.2 percent respectively. These antibodies probably represented secondary immune responses. Of 58 transplant patients with prior potentially significant antibodies, 8 required 7 to 110 units of antigen-untyped blood after 8 to 28 units of antigen-negative blood; of these patients, one had subsequent hemolysis. Positive direct antiglobulin tests in 24 percent of adults and 10 percent of children were most often thought to be due to nonspecific adsorption of IgG. Anti-recipient ABO antibodies developed in 22 of 60 (37%) evaluable ABO-unmatched grafts; 13 cases had associated hemolysis. In all, 36 percent of adults and 20 percent of children had diverse RBC antibody problems. Resolution of these problems is an important part of the laboratory support necessary for a liver transplantation program.The Blood Bank plays an important role in the supportive care of liver transplant patients before, during, and after surgery. Before transplant for end-stage liver disease, patients are often transfused for bleeding due to portal hypertension, esophageal varices, deficient coagulation factors, thrombocytopenia, or other surgery. After transplant, many patients need further transfusions and some require retransplantation. The liver transplant program at the University of Pittsburgh has the world's largest such experience, and since the program's inception in 1981, its overall perioperative and postoperative blood use has been carefully documented.1 -5 These patients have ample opportunity for red cell (RBC) alloimmunization.The purpose of this study was to examine all RBC antibody problems encountered in 1000 consecutive liver transplants performed in our center from February 1981 to February 1987. Previously, as part of an examination of the relationship of the HLA system to RBC alloimmunization, 6 we reported a 9.5 percent frequency of potentially significant RBC alloantibodies in 263 adults. We present here our cumulative experience in both adults and children with regard to 1) the overall frequencies of RBC antibodies; 2) the onset and duration of significant RBC antibodies relative to transplant immunosuppression; 3) the cases in which insufficient compatible blood was available for surgery; and 4) the frequencies and causes of © J. B. Lippincott Co.

During the first 5 years (1981)(1982)(1983)(1984)(1985) of the liver transplantation program in Pittsburgh, a total (preoperative, intraoperative, and postoperative) of 18,668 packed red cell units, 23,627 fresh-frozen plasma units, 20,590 platelet units, and 4241 cryoprecipitate units was transfused for the procedures. This represents 3 to 9 percent of the total of blood products supplied by the Central Blood Bank to its 32 member hospitals. Six hundred thirty-six (636) transplants were performed on 485 patients in two hospitals: the Presbyterian University Hospital (564 beds) and Children's Hospital of Pittsburgh (236 beds). All of the blood components used in the operations were procured and released by the Central Blood Bank. This report describes some of these findings.The Development of liver transplantation (LTx) programs in recent years has put new demands on blood banks and transfusion services, which must devise means of coping with this new challenge. The Central Blood Bank of Pittsburgh (CBB) provides blood product support for 32 member hospitals. Two of these hospitals, Presbyterian University Hospital (PUH, 564 beds) and Children's Hospital of Pittsburgh (CHP, 236 beds) began doing liver transplants in 1981. The results of this experiment are reported here. Study ResultsFigure 1 divides the numbers of operations done in Pittsburgh by 1) the year of transplantation, 2) the hospital, and 3) the number of transplantations per patient. The numbers increased almost exponentially. Table 1 shows that, during the first 5 years, 290 adults and 195 children underwent 626 LTx. Of these, 61 adults and 54 children received two livers, and 15 adults and 11 children received three livers. Table 2 shows the components used preoperatively, intraoperatively, and postoperatively. Most packed red cells (RBCs) (64%) and cryoprecipitate (86%) were used intraoperatively. Slightly more than one-half of the fresh-frozen plasma (FFP) and less than one-half of the platelets were used in the operating room. Table 2 also compares the total number of components used for © J. B. Lippincott Co.