Ej Lee

ABO compatibility can influence the results of platelet transfusion. Results of a randomized trial

Sixty consecutive patients with untreated acute leukemia alternately received either ABO‐matched or ABO‐mismatched random‐donor platelet transfusions prepared from pooled platelet concentrate stored for 1 to 3 days. Patients were assigned randomly to receive matched or mismatched platelets as their first transfusion, and the first four transfusions were analyzed. In 40 evaluable patients, there was no significant difference (paired t test) between the 10‐minute posttransfusion corrected count increments (CCI) of the initial transfusions of matched and mismatched platelets. In contrast, the second matched transfusion was significantly better than the second mismatched transfusion. This effect of ABO compatibility was particularly pronounced in a subset of patients. Six patients in whom mismatched transfusions were consistently inferior to matched transfusions had either a significant increase in anti‐A or ‐B isoagglutinin titers following the first transfusion or elevated titers before or at the conclusion of the study. Conversely, in five patients in whom there was no apparent effect of ABO mismatching, only one had an increase in isoagglutinin titer. Platelet survival was not altered as the ratio of 18‐hour to 10‐minute posttransfusion CCI was 0.6 for both matched and mismatched platelet transfusions. These data demonstrate that ABO compatibility can affect the results of random‐donor platelet transfusions and that patients who experience poor increments from ABO‐mismatched platelets may benefit from a trial of ABO‐compatible platelets before the initiation of HLA‐matched platelet transfusion.

The value of 10‐minute posttransfusion platelet counts

Monitoring of platelet counts 1 hour after transfusion has become standard practice in most centers. In this study, platelet counts obtained 10 and 60 minutes after 48 platelet transfusions were compared. There was a close, linear relationship (r = 0.98) between these values over a wide range of posttransfusion counts, indicating rapid equilibration of transfused platelets. Ten‐minute posttransfusion samples are easier to obtain and are convenient for both patients and medical staff.

Intravenous immune globulin for patients alloimmunized to random donor platelet transfusion

Immune globulin, prepared as a chemically and enzymatically unmodified solution in 10 percent maltose at pH 4.25, was administered intravenously, at a dose of 0.4 g per kg per day for five consecutive days, to seven alloimmunized patients who had acute nonlymphocytic leukemia. All patients had an approximately threefold rise in IgG level. Five patients showed no change in lymphocytotoxic antibody (LCTAb) activity and no response to random donor platelets that were administered after the immune globulin. The activity of LCTAb either disappeared or diminished after immune globulin infusion in two patients, and they had borderline acceptable corrected count increments 1 hour after transfusion of pooled random‐donor platelet transfusions. Because of the diminished LCTAb activity, the improvements in response to pooled random‐donor platelet transfusions cannot be ascribed to the administration of immune globulin. High‐dose intravenous immune globulin has not been shown to be effective in reversing the effects of alloimmunization.

An evaluation of combinations of diaziquone, etoposide and mitoxantrone in the treatment of adults with relapsed or refractory acute myeloid leukemia : results of 8722, a randomized phase II study conducted by cancer and leukemia group B

A phase II trial was conducted to determine which of the three possible two-drug combinations of diaziquone, etoposide and mitoxantrone was associated with the highest response rate in patients with relapsed or refractory acute myeloid leukemia (AML). Of the 167 patients (median age 55) with AML who entered the trial, 123 were in first relapse, 22 were in second relapse and 22 had failed to achieve complete remission (CR). CR rates were 30% for diaziquone and mitoxantrone, and 23% for the other two combinations (mitoxantrone/etoposide and diaziquone/etoposide), NS. Patients in first relapse had higher CR rates (40%) than other patients. Of the 166 patients who actually received treatment, 43 died before having either a CR or persistent leukemia. Non-hematologic toxicity was primarily mucosal with 24% of patients experiencing grade 3 or greater stomatitis on the two diaziquone arms, and 43% on the mitoxantrone/etoposide arm. The combination of diaziquone and mitoxantrone was selected for further testing in patients with AML.

Clinical and cytogenetic features of familial erythroleukaemia

A family is described in which six members developed acute nonlymphocytic leukaemia (ANLL) over the past 1 5 years, all morphologically FAB M6. Five affected individuals (ages 54‐73) are members of a single sibship, the sixth (age 31) was the son of one of the affected sibs. The family lives in a rural area, and no environmental hazard has been identified. One of the six patients never resided in the same geographic area as the others. Three patients with leukaemia died without chemotherapy, two died shortly after the initiation of chemotherapy and the most recent patient never achieved remission, surviving 10 months. Bone marrow specimens from the two most recent patients were analysed for cytogenetic abnormalities using chromosome banding techniques. In addition, skin fibroblasts were examined in a single patient. The fibroblasts had a normal karyotype. Bone marrow cells from both patients had complex abnormalities. Some similarities were observed, including: (1) hypodiploidy; (2) loss of one chromosome 20; (3) the presence of multiple marker chromosomes. In each case one marker appeared to involve the‘missing’no. 20 with an alteration of the long arm—loss (20q —) in one patient and gain (20q +) in the other. Peripheral blood lymphocytes were grown in folate deficient medium, but no evidence for folate sensitive fragile sites was found. Marrow chromosomes from a third leukaemic sibling were examined without banding techniques in 1976 and the karyotype was 45.XY, — 18, — F(19 or 20), ‐I‐marker. No specific cytogenetic finding was common to the three patients studied except for the loss of an F group chromosome. This family is unique in the literature with six cases of familial leukaemia of the same morphologic subtype, and the cytogenetic findings suggest that loss or rearrangement of part of the long arm of a single chromosome 20 may have occurred in each of the three patients examined.

Use of ‘Split’ Plateletpheresis Products for Alloimmunized Patients

Single donor platelets obtained using the COBE Spectra were split into two halves and administered to alloimmunized patients with leukemia at two different points in time. The mean platelet yield was 6.83 times 1011(n = 63) with 56% of collections having yields of >6.0times1011(i.e. twice the current AABB recommendation for an apheresis platelet transfusion). In 58 instances, the two halves were administered to the same patient 24–96 h apart. The differences in the correct increments of the split transfusions administered 24–48 h apart were not statistically significant, although there were decreased increments after 72 and 96 h of storage. In 5 instances when the CCI for first transfusion was unacceptably low, the second half was successfully transfused to another patient. This study proves it is feasible to split apheresis platelets into two transfusions, and discusses approaches to optimally use this strategy for the transfusion support of alloimmunized patients.