Search

Erythropoietic protoporphyria (EPP) is characterized by a deficiency of ferrochelatase the final enzyme of the heme biosynthetic pathway. Patients with EPP may overproduce protoporphyrin IX, chiefly in developing erythrocytes. In some, protoporphyrin accumulates and causes toxicity, particularly to the skin and liver. Orthotopic liver transplantation (OLT) treats the severe liver disease that sometimes occurs in EPP; however, it does not correct the underlying metabolic disorder. We recently reported a patient with EPP who was improved with plasmapheresis and i.v. heme-albumin before OLT. Subsequently he developed histological and biochemical evidence of recurrent hepatotoxicity from protoporphyrin in the graft liver. We now report successful treatment of the patient with additional plasmapheresis and heme-albumin with improvement of hepatic histological and biochemical abnormalities. We conclude that plasmapheresis and heme-albumin are of benefit in EPP complicated by hepatotoxicity before and after liver transplantation.

Erythropoietic protoporphyria (EPP) is marked by a deficiency of ferrochelatase, which occurs in all cells and tissues, preventing effective conversion of proto porphyrin IX to heme and thereby blocking effective feedback inhibition of heme synthesis. The major source of the excess protoporphyrin is the bone marrow. Protoporphyrin IX may accumulate, with resultant toxicity chiefly of the marrow, skin, nervous system, and liver. Orthotopic liver transplantation (OLT) is, at present, the only adequate intervention for severe liver compromise secondary to protoporphyrin deposition, but it has been complicated by severe photosensitivity and polyneuropathy. Intravenous heme and plasmapheresis have been proposed but not previously reported as means to reduce the protoporphyrin burden before liver transplantation. We report a man with EPP who underwent preoperative heme-albumin administration and plasmaphereses that led to marked reductions in plasma and erythrocyte protoporphyrin levels. His OLT was uneventful, and he developed neither polyneuropathy nor exacerbation of photosensitivity.

We studied the efficiency of platelet collection by the Mobile Collection System (MCS) using two types of experimental protocols and evaluated the effect of storage at 22 degrees C on the platelet concentrates (PC). MCS is a new blood cell separator that combines discontinuous flow features with a new computerized operating system and can be used to harvest either full units of apheresis PC (SDP protocol) or half units of PC together with one to two units of plasma (PLP protocol). On the average, 1.98 x 10(11) +/- 0.46 x 10(11) (mean +/- SD) platelets were obtained by the PLP protocol and 3.01 x 10(11) +/- 0.70 x 10(11) and 4.2 x 10(11) +/- 1.12 x 10(11) by the early and later versions of the SDP protocols, respectively. The mean number of WBC per PC ranged from 3.3 to 4.7 x 10(8). During the storage period pH stayed above 7.0. On the average, the production of one molecule of lactate corresponded to the consumption of 0.538 molecules of glucose, indicating that less than 8% of glucose was consumed by the oxidative pathway. There were only small increases in LDH and B thromboglobulin concentrations. Furthermore, the ability of platelets to recover from osmotic shock and to aggregate following exposure to dual agonists declined only slightly during storage, indicating that both viability and function of platelets collected by the MCS were preserved during storage.

Erythropoietic protoporphyria (EPP) is characterized by a deficiency of ferrochelatase the final enzyme of the heme biosynthetic pathway. Patients with EPP may overproduce protoporphyrin IX, chiefly in developing erythrocytes. In some, protoporphyrin accumulates and causes toxicity, particularly to the skin and liver. Orthotopic liver transplantation (OLT) treats the severe liver disease that sometimes occurs in EPP; however, it does not correct the underlying metabolic disorder. We recently reported a patient with EPP who was improved with plasmapheresis and i.v. heme-albumin before OLT. Subsequently he developed histological and biochemical evidence of recurrent hepatotoxicity from protoporphyrin in the graft liver. We now report successful treatment of the patient with additional plasmapheresis and heme-albumin with improvement of hepatic histological and biochemical abnormalities. We conclude that plasmapheresis and heme-albumin are of benefit in EPP complicated by hepatotoxicity before and after liver transplantation.

Transfusion protocols have remained unchanged for decades. Accordingly, it is necessary to avoid transfusion reactions by giving patients ABO- and irregular antibody-compatible red blood cells (RBC). Prevention of immunization to the Rh antigen D is also required since anti-D may cause a serious hemolytic disease of fetus and newborn. Prevention of transfusion-induced immunization to other blood group antigens is neither required nor feasible for the general transfused population. We consider the process of alloimmunization to be harmful due to the following untoward effects: 1) Destruction of transfused RBC negates transfusion's intended therapeutic benefits and may cause transfusion reactions. 2) Some alloantibodies become undetectable after a relatively short period (e.g., anti-Jka) so that in the future such seemingly compatible transfusions cause severe, sometimes fatal delayed transfusion reactions. 3) RBC autoimmunity may follow alloimmunization and cause hemolytic anemia in the recipient. To take the first step toward preventing transfusion-induced alloimmunization we calculated, using our antibody database, the immunogenicity of RBC antigens in a predominantly white female and male populations according to the methods of *Giblett (Transfusion 1961;1(4): 233) and **Tormey and Stack. (Blood 2009;114: 4279). The latter method corrects immunogenicities for antibody evanescence. The Table below shows that the three highly immunogenic antigens against which clinically significant antibodies were frequently formed were E, Jka and K, both in females and males. Immunogenicity of Rh C antigen was not calculated, since anti-C occurs most often with anti-D. Figure 1 Figure 1. In summary, we suggest a first step toward improving immunological safety of RBC transfusions by preventing immunization to E, Jka and K antigens. Automated typing or DNA analysis would facilitate mass typing of both donors' and recipients' RBC antigens. Disclosures No relevant conflicts of interest to declare.

Development of RBC autoantibodies in three Rh-negative patients following treatment with Rh-positive FFP is reported. Patients’ alloimmunization to Rh D antigen dates back several years. Patient I, a 49-year old man, experienced an acute cardiac event due to ascending aortic dissection, aortic insufficiency and probable cardiac tamponade. His blood type was O, Rh negative and his serum contained no alloantibodies. He underwent cardiac surgery on emergency basis and experienced bleeding complications during the procedure. He received 53 units of RBC, 49 of them Rh- positive and many other blood products. On the 8th post-operative day the patient experienced cardiac tamponade, which was relieved surgically. Then his blood type was O, Rh positive and anti-D was detected in his serum due to primary immunization to the Rh D antigen. The patient was re-admitted three months later for sharp epigastric pain. During that hospitalization no blood products were transfused; hematocrit varied between 33 to 29%. Blood typed as O, Rh negative, and manual direct antiglobulin test (DAT) was microscopically positive for IgG. Automated DAT was strongly positive for IgG1. Anti-D, anti-E and a panagglutinin (autoantibody) were present in his serum. The panagglutinin reacted strongly (2+) with Rh-positive RBC and less strongly (1+) with Rh-negative RBC, but both reactivities could be removed by absorption onto Rh-negative RBC. This “mimicking” antibody represented an autoantibody that was induced by alloimmunization to Rh antigen D. Eleven years later the patient was readmitted for bleeding duodenal ulcers. His serum contained anti-D, anti-C, anti-E and anti-K. DAT was negative for the first three days. During the first 19 days of hospitalization he received seven units of compatible RBC and 16 units of Rh-positive FFP. Anti-D was present in the eluate from patient’s Rh-negative RBC during days 18 to 28. The patient had again developed an autoantibody after receiving Rh-positive FFP, which apparently contained RBC fragments. Patient II was a 58-year old woman who underwent coronary artery bypass surgery. Her blood type was B, Rh negative and her serum contained anti-D and anti-K. During surgery and postoperative period she received ten compatible units of RBC and two units of B, Rh-positive FFP. The immediate post-operative course was unremarkable, but when discharged 8 days after surgery she had slight fever of unknown origin and Hct was 32.2%. Nine days later she was admitted to another hospital with fever of 101oF, jaundice, melena, chest pain, leg pain and anemia (Hb 7.2gm/dL). Reticulocytes were 14.8% and haptoglobin was 0. No new alloantibodies were detected. She had a weakly positive manual DAT. The automated DAT showed severe coating of RBC with IgM. Autoimmune hemolytic anemia was diagnosed. Following prednisone therapy her hemoglobin and hematocrit levels normalized. We believe that the autoantibody was induced by RBC fragments in the Rh-positive FFP. Patient III was a 72-year-old woman with admission diagnosis of possible HUS. The patients’ true blood type was A, Rh negative and her serum contained anti-C and anti-D. However, the initial blood sample was collected from a wrong patient whose blood type was O, Rh positive. Therefore she received four units of O, Rh-positive FFP before plasma exchange therapy was initiated. Her group A RBC were destroyed by anti-A in the transfused FFP. Surprisingly anti-D was also detected in the eluate of patients’ Rh-negative RBC. At that time the titer of anti-D had increased significantly over the original. Following destruction of anti-A coated RBC she still remained anemic, probably due to the autoantibody. After prednisone therapy Hct normalized steadily. In summary, three Rh-negative patients with existing alloimmunization to the Rh antigen D developed anti-D mimicking autoantibodies after receiving Rh-positive FFP. The autoantibodies caused autoimmune hemolytic anemia in two of the patients. Further studies on RBC autoimmunization in alloimmunized patients are encouraged. Disclosures No relevant conflicts of interest to declare.

Abstract 4377 In men blood group incompatibilities between a donor and blood transfusion recipient may stimulate RBC antibody production, whereas in women both transfusion and pregnancies play a role. Immunogenicities of various RBC antigens correlate with their ability to induce a specific antibody response. These parameters were calculated on data obtained previously in 711 patients found to be immunized in pre-transfusion tests using the method of Giblett (Transfusion 1961), and corrected for the fraction of antibody decline in time by the method of Torney and Stack (Blood 2009). Immunogenicities of RBC antigens expressed as a fraction of that of the K antigen (Potency = 1) are shown in columns IV & VII (method of Giblett) and in V & VIII (method of Torney & Stack) of the following table. I Antigen X II Anti-X, N III Anti-X, Females, N IV Females Potency vs. K V Females, Corrected Potency VI Males, Anti-X, N VII Males, Potency Vs. K VIII Males, Corrected Potency C 71 51 0.227 0.156 20 0.108 0.075 c 37 27 0.164 0.141 10 0.074 0.063 E 220 117 0.554 0.565 103 0.594 0.606 e 9 5 0.244 4 0.238 Fya 44 28 0.122 0.086 16 0.085 0.060 Fyb 3 1 0.007 0.004 2 0.017 0.012 Jka 60 41 0.225 1.083 19 0.127 0.611 Jkb 5 3 0.015 2 0.012 K 153 84 1 1 69 1 1 k 1 1 0.488 0 S 18 13 0.051 0.027 5 0.024 0.013 s 1 0 1 M 21 10 0.056 0.069 11 0.075 0.093 In males the corrected potencies of E and Jka were about 60% of that of K, but in females the corrected potencies of Jka and K were equal. The antigens C, c, Fya,Jka and S had higher corrected potencies in females than in males, probably reflecting the additional role of pregnancies in immunization. Note the big difference in antibody response between allelic non-Rh antigens (e.g. Jka vs. Jkb). Immunogenicity of the Rh D antigen was not calculated since Rh negative patients receive Rh negative blood and Rh negative pregnant women are given Rh immune prophylaxis. However, in this study 29.6 % of the patients were Rh negative. Over 70% of the susceptible patients had been immunized to the Rh D. In conclusion, RBC antibodies interfere with the benefits of RBC transfusions and may also cause severe adverse effects. Introduction of molecular methods into Blood Bank setting could eventually minimize exposure and immunization of transfusion recipients to incompatible RBC antigens. Information about immunogenicity of various blood group antigens may point out those antigens that should not be given to patients who are lacking them. It is also critical to understand why immunization to the D antigen is still prevalent in order to pave the way to future multiple antigen matching. Disclosures: No relevant conflicts of interest to declare.

Abstract 2276 Is has long been known that RBC antibody detection is enhanced following a decrease in the ionic concentration. In the past we added into our routine pre-transfusion antibody screen a new test, which employs ionic strength conditions between 15 to 17% of the ionic strength of 0.9% NaCl (vLIS/IAT): 2 drops of patient's plasma and one drop of 3% RBC are incubated for 15 minutes in 0.5 mL of 5% mannitol, pH 6.0 with phosphate buffer, containing 8mM EDTA. The RBCs are washed with normal saline and tested for agglutination by an anti-IgG reagent. Other published low ionic strength methods decrease the ionic concentration less, up to about 50%. In the process of pre-transfusion testing we found 711 patients with one, two or more blood group antibodies. The following table shows the specificities and quantities of clinically significant antibodies detected by these two methods. The following antibody specificities were not included: those that were present only in small quantities, directly agglutinating IgM antibodies and anti-Lea and Lebantibodies which are usually considered to be clinically insignificant. Antibody specificity Total Number detected % Detected by IAT % Detected by vLIS/IAT C 71 71.8% 93.0% c 36 80.5% 92.0% D 147 68.7% 97.3% E 220 40.3% 95.5% Fya 44 70.5% 95.5% Jka 60 60.0% 96.7% K 154 89.0% 76.0% M 23 34.8% 87.0% S 18 50.0% 100% Total 773 Avg. 62.8% Avg. 92.6% Overall, vLIS/IAT detected an increase in clinically relevant antibodies compared to IAT. This is clearly seen in the case of anti-E, anti-D, anti-Jka, anti-M and anti-S antibodies. Anti-K antibodies, however, were detected preferably by IAT. It should be noted that more anti-Le antibodies, although not shown here, were detected either by IAT or by direct agglutination (IgM antibodies). In summary, these data show that vLIS/IAT improved antibody detection when incorporated into routine pre-transfusion tests. They also indicate that one method does not detect all clinically significant antibodies; therefore it is beneficial to use two methods which in combination cover the varying spectra of RBC antibodies. Disclosures: No relevant conflicts of interest to declare.

The survival of autologous red blood cells (RBCs) collected during operation from the surgical field and processed immediately by the Haemonetics Cell Saver was compared to the survival of autologous nonprocessed RBCs obtained by venipuncture in nine patients undergoing reconstructive vascular operations and four patients undergoing coronary artery bypass. A double isotope technique (Cr-51 and In-III***) was used to determine the survival of the different cell populations. Seven patients undergoing coronary artery bypass served as controls to characterize the isotopes by labeling the same population of RBCs with each radionuclide. Comparison of the data in all groups failed to show any significant difference in either the immediate or long-term survival between autotransfused (Cell Saver-processed) blood and nonprocessed RBCs. This study indicates that shed blood collected and processed at operation with the Haemonetics Cell Saver can be autotransfused and that the in vivo survival of these cells is not significantly different from the survival of nonprocessed blood.

Utilizing an automated antiglobulin test, we have investigated the presence of the third and fourth components of human complement on normal red blood cells (RBCs). Only negligible amounts of the fourth component, C4, could be detected on either freshly collected or stored RBCs. The fragment C3d of the third component, C3, was detectable on both freshly collected and stored normal RBCs. A product derived from C3 and reacting with anti-C3c antibody was only barely detectable on freshly collected normal RBCs. During storage of blood at 4°C, increasing quantities of this material were detected on the RBC membrane. Bromelin treatment rendered stored RBCs completely nonreactive with anti-C3c antibody, whereas only partial loss of reactivity was observed following incubation with heated plasma. In contrast, incubation of EC43 with heated plasma completely abolished their ability to react with anti-C3c antibody. We suggest that the presence of this C3 fragment on stored RBCs may contribute to the development of ‘preservation injury’.

Objective: The aim of the study was to compare the clinical effects and hemostatic efficiency of transfusions of platelets preserved in the frozen state for as long as 2 years with transfusions of platelets preserved in the conventional manner for as long as 5 days in patients undergoing cardiopulmonary bypass. Methods: Seventy-three patients were prospectively randomly assigned to receive transfusions of cryopreserved or liquid-preserved platelets. Nonsurgical blood loss was measured during and after the operation. Bleeding time, hematologic variables, and the bleeding time site shed blood were assayed before cardiopulmonary bypass and at 30 minutes and 2, 4, and 24 hours after transfusion. In vitro platelet function tests were conducted on platelets obtained from healthy volunteers. Results: No adverse sequelae of the transfusions were observed. Blood loss and the need for postoperative blood product transfusions were lower in the group receiving cryopreserved platelets. Lower posttransfusion platelet increments and a tendency toward decreased platelet survival were observed in patients receiving cryopreserved platelets. Hematocrit and plasma fibrinogen were significantly higher in this group, and the duration of intubation was shorter. In vitro, cryopreserved platelets demonstrated less aggregation, lower pH, and decreased response to hypotonic stress but generated more procoagulant activity and thromboxane. Conclusions: (1) Cryopreserved platelet transfusions are superior to liquid-preserved platelets in reducing blood loss and the need for blood product transfusions after cardiopulmonary bypass. (2) The reduction in blood loss in the patients receiving cryopreserved platelet transfusions after cardiopulmonary bypass probably reflects improved in vivo hemostatic function of cryopreserved platelets. (3) Some in vitro measures of platelet quality (aggregation, pH, hypotonic stress) may not reflect in vivo quality of platelet transfusions after cardiopulmonary bypass, whereas other in vitro measures (platelet procoagulant activity and thromboxane) do. (J Thorac Cardiovasc Surg 1999;117:172-84)

Anti-A autoantibody manifested itself clinically in fatal hemolysis and kidney failure in the following case. Case Report A 73-year-old man suddenly experienced severe bilateral lumbar pain associa...