Residual White Blood Cell Count Research Articles

Application of flow cytometry in transfusion medicine

Flow cytometry-based testing approaches have no longer remained restricted to the research laboratories. With widening of its horizons in the field of diagnostics in oncology and transplantation medicine, the flow cytometer-based testing approach is now relevant to many aspects of the field of transfusion medicine. Two of the most important applications of flow cytometry in transfusion medicine are the enumeration of CD34-positive cells in the peripheral blood and stem cell product and the enumeration of residual white blood cell counts in blood product as a quality control measure. The flow cytometer-based crossmatch for detection of donor-specific anti-human leukocyte antigen antibodies is also gaining popularity in the field of histocompatibility and immunogenetics. The utility of this platform in the field of immunohematology is also increasing and looks promising for clinical decision-making in the near future.

Trans-perineal pumpkin seed oil phonophoresis as an adjunctive treatment for chronic nonbacterial prostatitis.

BackgroundA significant number of men who are younger than 50 years visit urologists for interminable prostatitis. This study aimed to thoroughly investigate the effect of pumpkin seed oil (PSO) phonophoresis on chronic nonbacterial prostatitis (CNBP).Subjects and methodsSixty patients with CNBP were randomly assigned to three groups: Group A, wherein patients were treated with PSO using phonophoresis; Group B, where patients underwent transperineal continuous low-intensity ultrasound (LIUS); and Group C, wherein patients underwent placebo LIUS. All three groups received their corresponding treatments daily for up to 3 weeks. The NIH-Chronic Prostatitis Symptom Index (NIH-CPSI), residual urine determined by urodynamic measurements, and flow rate were used to analyze study outcomes. The white blood cell (WBC) count in the prostatic secretion was determined.ResultsComparisons of the intragroup mean values of all measurements in Groups A and B before and after the end of the treatment showed a significant improvement in residual urine, flow rate, WBC count, and NIH-CPSI (p < 0.05), whereas no significant change was found in Group C (p > 0.05). Between-group comparisons of all variables showed a significant difference was found after intervention (p < 0.05). Postintervention comparisons between Groups A and B showed a significant difference in all measurements, except for WBC, in favor of Group A. Comparing the changes between Groups A and C, a significant difference was found in all measurements (p < 0.05). Furthermore, all parameters differed significantly when comparing Groups B and C (p < 0.05).ConclusionThe current study showed that PSO phonophoresis can produce a significant effect in the management of CNBP and can, therefore, be considered a safe, noninvasive method for the treatment of CNBP.

Control de calidad de la leucorredución de plaquetas obtenidas por aféresis por medio de cámara de nageotte y cell-din ruby.

Fundamentos: Los componentes sanguíneos obtenidos con aféresis ofrecen mayor seguridad a los receptores, la verificación de la leucorreducción es un paso importante en este proceso, por tal razón se hace necesario comparar por medio de dos metodologías diferentes el conteo residual de glóbulos blancos de plaquetas obtenidas por aféresis. Diseño de estudio y métodos: Se realizó un estudio de corte transversal descriptivo en la Fundación Hematológica Colombia. Bogotá – Colombia. Se realizó un muestreo aleatorio simple con el fin de realizar la verificación del recuento de Glóbulos Blancos por cámara de Nageotte y Cell dyn Ruby. Para el análisis de los datos se aplicaron medidas de tendencia central y de dispersión para las variables cuantitativas, (IC 95%) y correlación de Spearman para el análisis de procedimientos satisfactorios (Prueba T). análisis de los datos se realizó en el programa Spss Versión 19. Resultados: La población de estudio estuvo conformada por 124 Muestras de Plaquetas obtenidas por aféresis. En relación al recuento de células para las dos metodologías presentaron un promedio de 0,057 vs 0,003 células contadas el valor máximo para las dos metodologías fue de 0,34 – 0,44. Conclusiones: las muestras analizadas presentaron recuentos residuales de Glóbulos Blancos por debajo de 5,0 x 106 valor estimado para definir la unidad como leucorreducida. Ninguno de los valores máximos superó el valor de referencia.

Assessment of leucoreduction of sickle cell trait blood: quality of the filtered product.

With the implementation of universal leucoreduction of blood components in several industrialised countries, the problems associated with leucocyte filtration of sickle cell trait blood have been reconsidered. In this study, we assessed the use of high performance filters for leucoreduction of packed red blood cells donated from subjects with sickle cell trait and evaluated the incidence and recurrence of altered red blood cell filterability. Twenty-one volunteer donors with HbAS were compared to 21 donors with HbAA selected at random. The main parameters analysed were residual white blood cell count and post-filtration haemolysis. Filtration times, flow, volume and haemoglobin loss of the packed red blood cells were also determined. In all, 33% of HbAS red blood cell units with slow flow and prolonged filtration time had high residual white blood cell counts. In 7.7% of cases, despite flow through the filter, the units were not leucoreduced properly. Haemoglobin and volume loss were significantly greater in the slow filtration group. Significant post-filtration haemolysis was present in half of the units with high residual white blood cell counts. Despite the development of new technology for filtration, the problem of filterability of blood from donors with sickle cell trait is not yet resolved. Altered filterability of blood from sickle cell trait donors cannot be predicted from the donors' characteristics and recurrence of the problem is not observed between donations. Screening blood donors for sickle cell trait to ensure the safety and quality of blood products for transfusion does, therefore, remain a relevant issue.

WBC reduction filtration efficacy performed at varying time intervals post‐collection

A multisite blood center experienced unacceptable post-leukoreduction filtration white blood cell (WBC) counts at a few centers. Since prefiltration storage time and temperature were suspect, whole blood (WB) units were stored in transport shippers for at least 2 hours, cooling toward 1-6 ° C, before filtration. This study compared the effect of storage times in transport shippers on the residual WBC counts of leukoreduced units. Collection and filtration of WB units were accomplished with the use of the Fenwal Express System with Integral Sepacell RZ-2000 WB Leukocyte Reduction Filter. Units were collected and placed in transport shippers containing ice. Leukoreduction filtration was performed at designated intervals post-collection. Acceptable leukoreduction was defined as < 5 × 10(6) residual WBC. Fifty donor units were selected randomly over 3 months. Units were held in transport shippers, and WBC reduction was performed at designated post-collection intervals. Storage times ranged from 28 to 458 minutes. All residual WBC counts were acceptable. Storage time of WB units in transport shippers did not play a role in the efficacy of the leukoreduction. This study demonstrated the 2-hour storage time before leukoreduction filtration could be eliminated resulting in time savings and increased efficacy in the component production laboratory.

Implementation of buffy coat platelet component production: comparison to platelet‐rich plasma platelet production

Buffy coat (BC) production of platelets (PLTs) has been successfully used in Europe for more than two decades. Currently, Canadian Blood Services is implementing the BC method. This article summarizes results of the validation testing performed to qualify the process of PLT production from whole blood and compares the quality of PLTs produced in routine production by either the PLT-rich plasma method (PRP-PCs) or the BC method (BC-PCs). Validation data included variables used for routine quality control (QC; pH, PLT count, volume, sterility, residual white blood cell count) as well as nonroutine testing of PLTs for PLT activation, metabolic changes during storage, and PLT responsiveness to hypotonic shock and the extent of shape change induced by adenosine 5'-diphosphate. BC-PCs were tested on Days 1 and 6. QC of production runs included the same routine tests performed on Day 6. PLTs produced by the BC method during validation and pilot implementation met all Canadian Standards Association standards with respect to yield, volume, pH, and leukoreduction. Additional validation testing indicated a moderate level of PLT storage lesion development. In comparison to PRP-PCs, in vitro variables of BC-PCs, either pH in this study, or other markers compared to the literature were better, suggesting that BC-PCs have less evidence of production-related damage and improved PLT quality during storage. PLT concentrates produced from whole blood by the BC method after an overnight hold have laboratory variables suggestive of a higher quality than those concentrates produced by the PRP method.

Quality of leucoreduced red blood cell concentrates: 5 years of follow‐up in France

Since 1998, prestorage leucoreduction of all cellular blood components has been made mandatory in France. The French blood service needed to follow the data on the quality of the blood components prepared by blood centres. Quality control (QC) data were submitted to a central data bank by each blood centre. The data were stratified by preparation method for analysis of key performance criteria - residual white blood cell (WBC) and total haemoglobin content. The red blood cell (RBC) preparation processes and the methods for measuring haemoglobin content and residual WBC count were those routinely employed by blood centres. Each year, more than 15,500 RBCs were tested. Red blood cells had a mean haemoglobin content between 53.6 and 54.9 g/unit depending on the year (2001 to 2005). The requirement of 40 g/unit was reached for about 99% of units. The haemoglobin content was influenced by the preparation process: 56.8 +/- 6.9 vs. 50.6 +/- 5.6 g/unit in average for whole blood filtration or RBC filtration, respectively. Apheresis RBCs exhibited a reduced variability (51.8 +/- 3.1 g/unit). The median residual WBC count remained low (0.046 to 0.057 x 10(6) WBCs/unit), and the percentage of RBC units exceeding the 1 x 10(6) WBCs/unit cut-off ranged from 1.5 to 0.6% depending on the year. A seasonal pattern was observed, with a significant increase (P < 0.001) of the median residual WBC count and of the percent of non-conforming units during the summer months. Our QC data suggest an overall compliance with the standard. Our data bank is useful to inform on the performance of leucoreduced RBC preparation processes carried out with market available devices.

Prospective, paired crossover comparison of multiple, single‐needle plateletpheresis procedures with the Amicus and Trima Accel cell separators

The Baxter Amicus Version 2.51 (A) and the Gambro BCT Trima Accel Version 5.0 (T) cell separators may produce multiple platelet (PLT) concentrates within a single donation. The single-needle multiple plateletpheresis procedures of the two devices were compared in a prospective, randomized, paired crossover study in 60 donors. The 120 donations were compared for donor comfort, collection efficiency, residual white blood cell (WBC) count, and (in selected patients) corrected count increment (CCI). The mean PLT yield and the resultant mean number of units per donation were significantly lower for A (6.06 x 10(11) vs. 7.48 x 10(11) and 2.57 vs. 3.19, respectively, both p < 0.001), in spite of a longer apheresis duration (89 min vs. 79 min; p < 0.001). This resulted in a higher collection rate of T (5.68 x 10(11) PLTs/hr vs. 4.10 x 10(11) PLTs/hr, p < 0.001). Residual WBC count of every unit was fewer than 5 x 10(6), but significantly fewer A-PLT donations contained more than 10(5) WBCs per unit (1 vs. 9, p = 0.008). Although the ACD-A consumption was slightly higher for A (489 mL vs. 469 mL, p = 0.04), a trend to a higher frequency of side effects was found for T (42.4% vs. 23.7%, p = 0.06). The 1-hour CCIs of 33 transfused A-PLT units were comparable with those of 43 T-PLT units (11.8 vs. 13.9, p = 0.480). Both cell separators showed safe collections of up to 4 PLT units per donation with adequate CCI. T produced a higher PLT yield despite shorter apheresis duration, but with slightly higher residual WBC counts and a trend to a higher side-effect frequency.

Prevention of primary transfusion‐associated cytomegalovirus infection in bone marrow transplant recipients by the removal of white cells from blood components with high‐affinity filters

A prospective study was carried out to determine whether use of cytomegalovirus (CMV) unscreened red blood cells and platelet concentrates, white blood cell (WBC) depleted with high-efficiency filters, would prevent transfusion-associated (TA) CMV infection in CMV seronegative bone marrow transplant recipients. Blood components were filtered in the bloodcentre under quality control and after filtration residual WBC counts were always below 5 x 10(6) cells/U. Since 1990, 23 consecutive allogeneic and 37 autologous CMV seronegative marrow transplant recipients, have been transfused with filtered blood components and followed for 6 months for evidence of CMV infection by monitoring culture and CMV serology. None of the patients showed clinical symptoms of CMV infection, and CMV cultures during episodes of fever were always negative. IgM anti-CMV antibodies were negative during the study in all patients. Low titres of IgG anti-CMV antibodies (5-12 relative ELISA units) were found in 24/60 patients during the first month after bone marrow transplantation (BMT), probably due to passive transfer of IgG administered with the platelet transfusions. 3 and 6 months after BMT, 56 and 48 patients respectively were still alive; and CMV serology was negative in all patients. The results show that TA-CMV infection is preventable by filtration of blood through high-efficiency filters in patients undergoing autologous and allogeneic BMT.