John A. Koepke

A controlled trial of prophylactic granulocyte transfusions during initial induction chemotherapy for acute myelogenous leukemia.

To evaluate the role of prophylactic granulocyte transfusions during remission-induction chemotherapy for acute myelogenous leukemia (AML) we randomized 102 infected patients either to receive daily granulocyte transfusions when blood granulocytes fell below 0.5 x 10(9) per liter (54 patients) or not to receive them (48). Although the percentage of patients acquiring any infection was similar in the transfusion and control groups (46 and 42 per cent, respectively), granulocyte transfusions decreased the proportion of patients with bacterial septicemia (9 per cent of those with transfusions vs. 27 per cent of the controls; P = 0.01). Granulocyte transfusions did not reduce the incidence of other infections or improve bone-marrow recovery, remission rate and duration, or survival. Seventy-two per cent of the patients given transfusions had transfusion reactions. Pulmonary infiltrates were more common in the transfusion group than in the control group (57 per cent vs. 27 per cent; P = 0.002). Thirty-five per cent of the patients with pulmonary filtrates died, as compared with 5 per cent of those without filtrates. We conclude that prophylactic granulocyte transfusions should not be used during remission-induction chemotherapy in AML because the risks outweigh the benefits.

The elimination of hydroxyethyl starch from the blood donors experiencing single of multiple intermittent-flow centrifugation leukapheresis.

The elimination of hydroxyethyl starch (HES) from donor blood was studied following either single or multiple intermittent‐flow centrifugation leukapheresis. Immediately following pheresis, serum HES concentrations fell rapidly. The rate of elimination then slowed with trace amounts of HES persisting for weeks. Pharmaco‐kinetic analysis using a two‐compartment open model revealed an average distribution half‐life and terminal half‐life of 3.84 and 48 days, respectively. After multiple phereses, HES accumulated in serum. Although the pattern of elimination was similar, the persistence of HES was more protracted, with the serum level predicted to reach the baseline at 72 weeks pastpheresis versus 38 weeks after a single pheresis. The importance in regards to toxicity, if any, of the persistence of trace amounts of HES in donor blood is presently unknown.

Use of Platelet Aggregometry in Selection of Compatible Platelet Donors

To determine if platelet aggregometry was useful in selecting compatible platelet donors, six patients who had become refractory to random platelets were studied. Serum from the patient was added to citrated platelet-rich plasma from the prospective donor in a standard aggregometry system. Serial aggregometry studies revealed no platelet aggregation unless the refractory state had been reached. At that time positive aggregation occurred only between the poorly matched pairs. A correlation between platelet aggregation and HL-A histocompatibility was noted. Family members with negative aggregation were selected as donors, and their platelets were able to provide consistently satisfactory increments in the platelet count of the recipient who was refractory to random donors. In contrast, platelets from family members who exhibited positive aggregation failed to do so. These findings suggest that platelet aggregometry can be used to select compatible platelet donors.

Selection of compatible platelet donors: a prospective evaluation of three cross-matching techniques.

A prospective study was undertaken to assess the values of platelet aggregometry, lymphocytotoxicity, and mixed lymphocyte cultures in selecting compatible donors for patients refractory to random platelet transfusions. Donors were selected at random without regard to HLA types. Concurrent with each platelet transfusion, platelet aggregometry and lymphocytotoxicity were performed using patient serum and donor cells. The results were compared with HLA types, MLC, and increments in platelet counts. Forty‐one transfusions were given to 21 patients; 27 were from related and 14 from unrelated donors. Platelet aggregometry was used successfully in selecting compatible donors in 37 cases (90%) with three false negative and one false positive results. Lymphocytotoxicity was useful in 73 per cent of cases with eight false negative and three false positive results. The response to platelet transfusions correlated poorly with HLA matches or MLC reactions. These data suggest platelet aggregometry and lymphocytotoxicity are useful cross‐matching techniques in selection of compatible platelet donors.

Complement Changes During Leukapheresis

Alterations of the complement system occurring during continuous‐flow filtration leukapheresis (CFFL) and intermittent‐flow centrifugation leukapheresis (IFCL) were assessed in 16 donors. Five blood samples were obtained at timed intervals during each cytaphere‐sis, three directly from each donor and two from the efferent lines returning blood from the leukapheresis machines to the donors. Components measured were C1, C2, C4, C3, C3‐C9 and CH50 of the classical, and factor B, properdin and properdin convertase of the alternative pathways. Changes in concentrations of components were compared to baseline values present in donor blood obtained prior to cytapheresis. During the first 10 minutes of CFFL, C2, C4, C3‐9 and CH50 were decreased (p < 0.05) in machine efferent fluids, but returned towards normal as the procedure continued. Changes in donor venous blood, decreased factor B, properdin and C3‐C9, were demonstrated only at the end of cytapheresis. During IFCL, significant (p < 0.05) decreases of C1, C2, C3‐C9 and factor B occurred in donor blood after 60 minutes of cytapheresis, however, all deficiencies except B corrected spontaneously as cytapheresis continued. In contrast, concentrations of C2, C4, C3‐C9, CH50 and factor B remained decreased in machine efferent fluids throughout the procedure. The data support those of previous studies that have demonstrated complement activation at the filter site during CFFL. Changes in donor venous blood are a new finding that may indicate in vivo activation of the alternative pathway. Profound changes of the complement system occur during IFCL also, but complement activation seems a less likely explanation. Instead, complement proteins may be lost by adsorption onto the surfaces of the IFCL software.

The Effects of Combined Platelet and Leukapheresis on the Blood Coagulation System

Analysis of blood coagulation was done on samples of blood collected from ten donors undergoing combined platelet and leukapheresis using the Haemonetics Model 30 Blood Processor. Blood samples were obtained from the donors prior to, during, and following pheresis. Blood was also obtained from the blood‐return line after the first collection of leukocytes and platelets, but before it was returned to the donor. Although the citrate anticoagulant was returned to the donor and there were some decreases in the concentrations of fibrinogen, platelets, and factors V and VIII, there were no changes of sufficient degree to suggest the development of a potential bleeding disorder. In addition there was no evidence to suggest that any activation of blood coagulation occurred during the pheresis or that thrombogenic substances were returned to the donors. Combined platelet and leukapheresis using the Haemonetics Model 30 Blood Processor, therefore, do not appear to subject the donor to risks for either bleeding or thrombotic complications.

Effect of intermittent-flow centrifugation leukapheresis on donor leukocyte counts.

Effects of intermittent-flow centrifugation leukapheresis (IFCL) on leukocyte counts in donor blood have not been reported. Accordingly, total and differential white blood cell counts were preformed serially during IFCL. A significant decrease (p less than 0.05) in all types of leukocytes occurred in donor blood early in pheresis and was probably the consequence of hemodilution. Concentrations of most leukocyte types remained decreased throughout the procedure, and a rebound leukocytosis was not detected. Thus, leukocyte kinetics in donor blood during IFCL differ from those reported for filtration leukapheresis in which the pattern of selective neutropenia followed by rebound neutrophilia has been ascribed to complement activation.

Function and morphology of platelets produced for transfusion by intermittent-flow centrifugation plateletpheresis or combined platelet-leukapheresis.

The effects on platelet function of intermittent‐flow centrifugation pheresis were measured employing platelets collected from ten donors by combined platelet‐leukapheresis with hydroxyethyl starch (LP) and from ten by plateletpheresis (PP) by similar techniques except without starch. Greater numbers of platelets were produced by LP than by PP. Aggregation of platelets collected by both LP and PP was normal (did not differ from prepheresis baseline) to collagen and to 10−5M adenosine diphosphate (ADP). Slight impairment to aggregation with 2 × 10−6M ADP and 5.5 × 10−5M epinephrine occurred with both techniques. These abnormalities, however, were significantly less severe in platelets collected by LP. Platelet morphology by electron microscopy was nearly normal, although glycogen granules were absent in LP platelets. Thus, hydroxyethyl starch, at doses currently used during a single LP, does not enhance abnormalities of platelet aggregation over those expected to result from PP alone. Actually, LP platelets function better in vitro than those collected by PP. Large numbers of platelets can be harvested by LP, and their use as a component that is comparable to PP platelets may mean improved efficiency and reduced costs for pheresis centers.

Platelet function in donors undergoing intermittent-flow centrifugation plateletpheresis or leukapheresis

Platelet dysfunction and prolonged bleeding have been seen in man when glucose polymer solutions, such as dextran, are used for volume replacement. Hydroxyethyl starch (HES) is a glucose polymer slightly different from dextran, which is used as a sedimenting agent in leukaphcresis procedures. This controlled study was performed to evaluate the effect of HES on platelet function in centrifugation leukapheresis donors. Plateletpheresis using the same machines and techniques but without HES was the control. Platelet function was assessed by bleeding time, platelet count, adhesiveness to glass beads and aggregation to collagen, epinephrine and several concentrations of ADP, before and after the pheresis procedures. Except for a decrease in platelet count after both procedures, no other major changes in platelet function were seen. After one exposure in previously unpheresed donors, HES does not induce platelet dysfunction.

Iron-deficiency anemia.

Insufficient dietary intake of iron and excessive red cell loss from chronic hemorrhage are the major causes of iron-deficiency anemia. The condition also may result from malabsorption or from increased iron requirements during pregnancy. Effective treatment is available in the form of oral, intramuscular or intravenous iron preparations, but the oral route is preferred for convenience, comfort and economy of administration.