Mechanisms of white cell reduction in red cell concentrates by filtration: the effect of the cellular composition of the red cell concentrates

The effect of platelets on the removal of white cells (WBCs) from 16 to 24-hour-old red cell (RBC) concentrates by filtration was studied. RBC concentrates with various concentrations of platelets and WBCs were filtered on a cellulose acetate column filter and on three polyester flatbed filters. The microscopic study revealed that lymphocytes and most monocytes were captured in the smaller pores of the fiber network, irrespective of the brand of filter, the type of filter material, or the prefiltration platelet amount in the RBC concentrates. In contrast, efficient granulocyte depletion depended on granulocyte-platelet interaction and on the filter material. In the presence of platelets, granulocytes were captured in the top part of the column filter or in the coarse layers of two of the flatbed filters, where platelets covered the fibers. Platelet depletion of the RBC concentrates prior to filtration diminished the contribution of these parts of the filters to granulocyte capture. A larger part of the column filter or the fine layers of the flatbed filters were now required for granulocyte capture. In one of the flatbed filters, granulocyte-platelet interaction occurred mainly in the fine layers, which ended in blockage of this filter after the filtration of variable volumes (250-600 mL) of standard RBC concentrates. A quantitative estimation of the effect of platelets on the WBC-reduction capacity found that all three flatbed filters had a highly significant decrease (p = 0.001) in WBC-reduction capacity for platelet-depleted or buffy coat-depleted RBC concentrates, as compared with standard RBC concentrates.(ABSTRACT TRUNCATED AT 250 WORDS)     

Institutional variation in hemotherapy for solid organ transplantation

BACKGROUND: Solid organ allograft recipients may require large amounts of blood components. The modification of components to make them safer for iatrogenically immunosuppressed transplant patients increases workload demands on blood banks and transfusion services. STUDY DESIGN AND METHODS: Institutions within the United States and Canada providing hemotherapy as support for transplant recipients were surveyed for their transfusion practices. RESULTS: Responses from 25 institutions provide the data for this report. In 1991, the mean intraoperative red cell requirements ranged from <1 unit for renal allograft recipients to 17.3 units for liver transplant recipients. The latter group also required the greatest amounts of platelets, fresh-frozen plasma, and cryoprecipitate. More than 75 percent of responding institutions provided either cytomegalovirus-seronegative or white cell-reduced cellular components to pediatric recipients of liver allografts and to both adult and pediatric recipients of heart, lung, and heart-lung allografts. The use of irradiated cellular blood components, although uncommon, was greatest in heart transplant recipients. The use of pretransplantation transfusions for immunomodulation was generally limited to patients awaiting a living-donor renal transplant. CONCLUSION: Transfusion practices varied among the institutions, but the majority provide cytomegalovirus-safe cellular blood components to heart and lung allograft recipients and to pediatric transplant patients. Gamma-radiated cellular components are not routinely provided to patients undergoing solid organ transplantation. Liver allograft recipients require the greatest amount of hemotherapeutic support.     

CONGENITAL ABSENCE OF THE GALLBLADDER: WAYS OF AVOIDING LAPAROTOMY

SUMMARY Two cases of congenital absence (agenesis) of the gallbladder seen at one hospital over a 5-year period are presented. One patient presented with ascending cholangitis due to choledocholithiasis, while the other presented with right upper quadrant abdominal pain and equivocal findings on ultrasound and oral cholecystography. Although diagnosis was made at laparotomy in both cases, it is likely that the arrival of laparoscopic cholecystectomy will avoid laparotomy in the future. The place of laparoscopy in establishing the presence of this anomaly is discussed.     

Evaluation of laboratory assays for screening antibody to hepatitis C virus

An evaluation study, involving 11 screening methods for the detection of antibody to hepatitis C virus (anti-HCV) and a panel of 500 serum samples, was performed. Samples were tested by all 11 methods, and those showing reactivity in at least one method were studied by a combination of supplemental assays (recombinant immunoblot assays, first and second generation; neutralization test for anti-c100; synthetic peptide immunoblot assay; recombinant multi-dot immunoassay) and classified as positive (110 samples), indeterminate (4 samples), or negative (386 samples) on the basis of the results obtained. Second- generation recombinant methods performed better on positive samples than first-generation assays or synthetic peptide-based methods (99.1- 100% correlation vs. 64.5-85.5% and 93.6-99.1%, respectively), whereas the latter showed higher correlations on negative samples than recombinant assays (97.4-99.7% vs. 82.4-93%). Further investigations, using broad panels of indeterminate samples from blood donors, should be done, however, before synthetic peptide-based methods are recommended for blood bank screening. Reactivity of samples must be confirmed by one supplemental test in all cases before the donor is informed. In some cases, it may require the use of two or more different tests to obtain definite conclusions.     

DIAPHRAGMATIC HERNIATION OF THE LARGE BOWEL ASSOCIATED WITH UNUSUAL CLINICAL AND ELECTROCARDIOGRAPHIC PRESENTATION

SUMMARY This is the first case reported of combined hiatus hernia of the stomach and herniation of the splenic flexure of the colon through the oesophageal hiatus. It was associated with unusual clinical and electrocardiographic findings. We postulate that these were the result of an increase in intrathoracic pressure induced by the herniating structures.     

Differentiation of anti-D, -C, and -G: clinical relevance in alloimmunized pregnancies

BACKGROUND: The differentiation of anti-D, -C, and -G specificities is seldom considered clinically important in pretransfusion testing. However, distinguishing these antibody specificities in alloimmunized pregnancies may be essential. The clinical prognosis as well as Rh immune globulin prophylaxis depends on the accurate identification of these antibodies. CASE REPORT: A pregnant woman, para 1 gravida 4, who had received Rh immune globulin at appropriate intervals during her previous pregnancies was reported to have anti-D (titer = 4) and anti-C (titer = 32). Differential adsorption and elution studies showed that the patient had anti-C and anti-G, but not anti-D. This case prompted retrospective examination of the sera from six other women with anti-D and anti-C who were referred to a high-risk pregnancy clinic. Of six pregnant women reported to have anti-D and anti-C; two had anti-D, -C, and -G; three had anti-D and -G, but not anti-C; and one had anti-C and -G, but not anti-D. This last is similar to the index case. CONCLUSION: Cases of pregnant women with anti-C and -G, but not anti-D, are not infrequent. Studies to differentiate anti-D, -C, and -G should be performed on alloimmunized pregnant women presumptively identified as having anti-D and anti-C when the medical history (Rh immune globulin prophylactic therapy) and/or titer values (e.g., anti-C titer higher than anti-D titer) suggest that anti-D may not actually be present. Rh immune globulin has not failed in these patients, and they should receive this therapy during pregnancy to prevent immunization to D.     

A DOUBLE-BLIND,COMPARATIVE STUDY OF DOTHIEPIN AND CLOMIPRAMINE IN THE TREATMENT OF MAJOR DEPRESSIVE ILLNESS

Dothiepin, a well-established antidepressant, has been compared with clomipramine in a single-blind study which demonstrated that dothiepin was better tolerated but there was no difference in efficacy. The present study was performed to recent European guidelines on good clinical practice using a randomised, double-blind, parallel-group methodology. One hundred and one patients suffering from major depressive disorder as defined by DSM-III-R were randomised to receive either clomipramine (25-150 mg daily) or dothiepin (75-150 mg daily) for up to six weeks. The clomipramine group comprised 51 patients, the dothiepin group 50 patients. At baseline, both groups had a mean age of 41-43 years and gave similar mean scores on the Hamilton Depression Rating Scale (23.5 for clomipramine, 23.6 for dothiepin). At endpoint it was reduced in both groups but there were no significant differences between the groups (mean change from baseline for the clomipramine and dothiepin groups was -14.6 and -14.1 respectively). Thirty-one clomipramine patients and 41 dothiepin patients completed six weeks' treatment. Withdrawal from treatment (20 patients for clomipramine, nine for dothiepin) was significantly different (p=0.0105). When reasons for withdrawal were analysed, 13 clomipramine patients and two dothiepin patients withdrew because of adverse events, this difference being significant (p=0.002). Thus both treatments were effective in treating patients suffering from major depressive disorder, but patients receiving dothiepin suffered fewer adverse events and were more likely to complete their treatment.