Bone Turnover Markers Changes Induced by Plateletpheresis May Be Minimized with Oral Supplementation of Calcium, Minerals, and Vitamin D before the Procedures: A Non-Randomized, Controlled Study.

Apheresis allows the collection of specific blood components but changes serum calcium (Ca), magnesium (Mg), copper (Cu), zinc (Zn), and hormones involved in bone metabolism due to citrate infusion. We assessed the effect of oral supplementation of calcium, vitamin D, and minerals as pills or an enriched diet before plateletpheresis donation on levels of divalent cations, hormones, and bone turnover markers that may prevent metabolic changes. Methods: Non-randomized controlled study including 134 donors. Serum parathyroid hormone (PTH), Ca, Mg, Zn, Cu, osteocalcin (OC), vitamin D, and type-1 collagen C-terminal telopeptide (CTX-1) levels were measured at baseline and post-procedure. Donors were divided into four groups: supplemented with calcium carbonate and vitamin D (cal + vitd); those receiving calcium, minerals, and vitamin D (cal + vitd + min); those receiving a calcium-rich diet (diet) and a control group (control). Results: PTH levels increased >1-fold, whereas tCa, tMg, Zn, Cu, iCa, iMg, and vitamin D levels decreased immediately after apheresis amongst donors of any group; when these levels were measured two weeks later, donors in the calcium-vitd and cal + vitd + min groups returned to basal values; donors in the cal + vitd + min group were the only group that kept their levels of OC and CTX unchanged at the different study times. Conclusions: Bone turnover markers changes induced by plateletpheresis may be minimized with oral supplementation of calcium, minerals, and vitamin D two days before the procedures.

PROCLEIX West Nile virus assay based on transcription-mediated amplification.

The PROCLEIX West Nile virus (WNV) assay is based on transcription-mediated amplification and is the most sensitive nucleic acid test commercially available today for blood screening. Since 2003, in the USA, the assay has been used for year-round screening of blood donations in minipools of 16 and in an individual-donation testing format, when appropriate triggering guidelines for such switch become effective. The test can be run on the semiautomated PROCLEIX modular platform or the fully-automated PROCLEIX TIGRIS System. This assay and the corresponding platforms have been developed and are manufactured by San Diego-based Gen-Probe, Inc., while they are marketed and distributed by Chiron, a Novartis business. This review covers some of the epidemiological and virological aspects of WNV, as well as clinical questions and technological assessment of the transcription-mediated amplification and alternative technologies used in WNV blood screening.

[Safety of the blood supply in Mexico from 1999 to 2003]. / La seguridad de las reservas sanguíneas en la República Mexicana durante los años 1999 a 2003.

INTRODUCTION: The incidence of the infection by the viruses of the human immunodeficiency (HIV), hepatitis B (HBV) and hepatitis C (HCV) has diminished enormously in developed countries during the last 20 years; nevertheless, in our country we do not know such an incidence and, therefore, the safety of our blood supply. MATERIAL AND METHODS: We performed a retrospective analysis at the Centro Nacional de la Transfusión Sanguínea (CNTS) assessing 17,176,298 serologic tests including HIV, HCV and HBV carried on 5,725,432 blood units collected and informed to the CNTS from January 1999 to December 2003 by all the Mexican blood banks. Prevalence, incidence and residual risk of each one of the aforementioned serologic markers were calculated. RESULTS: The five years mean prevalence for HIV, HBV and HCV has remained steady. The residual risk (RR) when hemagglutination test was employed was 1:977 for HCV; 1:1,564 for HBV and 1:1,262 for HIV. Whereas the RR when ELISA was performed decreased to 1:2,781 for HCV; 1:3,185 for HBV and 1:9,969 for HIV. If nucleic acid amplification test were employed, RR would be 1:8,170 for HBV; 1:9,915 for HCV and 1:19,939 for HIV. CONCLUSIONS: The theoretical risk for transfusion-transmitted diseases in our country is still worrisome.

La seguridad de las reservas sanguíneas en la República Mexicana durante los años 1999 a 2003 / Safety of the blood supply in Mexico from 1999 to 2003

Introduction. The incidence of the infection by the viruses of the human immunodeficiency (HIV), hepatitis B (HBV) and hepatitis C (HCV) has diminished enormously in developed countries during the last 20 years; nevertheless, in our country we do not know such an incidence and, therefore, the safety of our blood supply. Material and methods. We performed a retrospective analysis at the Centro Nacional de la Transfusión Sanguínea (CNTS) assessing 17,176,298 serologic tests including HIV, HCV and HBV carried on 5,725,432 blood units collected and informed to the CNTS from January 1999 to December 2003 by all the Mexican blood banks. Prevalence, incidence and residual risk of each one of the aforementioned serologic markers were calculated. Results. The five years mean prevalence for HIV, HBV and HCV has remained steady. The residual risk (RR) when hemagglutination test was employed was 1:977 for HCV; 1:1,564 for HBV and 1:1,262 for HIV. Whereas the RR when ELISA was performed decreased to 1:2,781 for HCV; 1:3,185 for HBV and 1:9,969 for HIV. If nucleic acid amplification test were employed, RR would be 1:8,170 for HBV; 1:9,915 for HCV and 1:19,939 for HIV. Conclusions. The theoretical risk for transfusion-transmitted diseases in our country is still worrisome.

Introducción. La transmisión del virus de la inmunodeficiencia humana (VIH), de la hepatitis C (VHC) y de la hepatitis B (VHB) por transfusión sanguínea ha disminuido de manera significativa en los países industrializados durante los últimos 20 años; sin embargo, en nuestro país aún no conocemos dicha incidencia y consecuentemente la seguridad de nuestras reservas sanguíneas. Material y métodos. Se realizó un estudio retrospectivo en el Centro Nacional de la Transfusión Sanguínea (CNTS) analizando 17,176,298 pruebas serológicas incluyendo VIH, VHC y VHB realizadas a 5,725,432 unidades de sangre captadas e informadas al CNTS de enero de 1999 a diciembre de 2003 por todos los bancos de la República Mexicana. Se calcularon la prevalencia, la incidencia y el riesgo residual para cada uno de los marcadores serológicos mencionados. Resultados. La prevalencia en los cinco años para el VIH, VHB y VHC se ha mantenido estable entre los donantes. El riesgo residual encontrado con la prueba de hemaglutinación fue de 1:977 para el VHC; de 1:1,564 para el VHB y de 1:1,262 para el VIH. Con la prueba de ELISA el riesgo descendió a 1:2,781 para el VHC; 1:3,185 para el VHB y 1:9,969 para el VIH. Si se empleara la prueba de amplificación de ácidos nucleicos, el riesgo disminuiría a 1:8,170 para el VHB; 1:9,915 para el VHC y a 1:19,939 para el VIH. Conclusiones. El riesgo de transmitir infecciones por transfusión sanguínea en nuestro país es todavía preocupante.

Hepatitis C seroprevalence in accepted versus deferred blood-donor candidates evaluated by medical history and self-exclusion form.

BACKGROUND: Hepatitis C virus (HCV) represents a viral pandemic that is five times as widespread as human immunodeficiency virus. Blood transfusion posed a major risk of HCV infection in developed countries before 1990, but the introduction of improved blood-screening measures has decreased the risk of transfusion-associated HCV infection, which may now be even lower since the introduction of screening of pooled samples by nucleic acid testing (NAT). Unfortunately, NAT is not affordable in most developing countries. The goal of this work is to assess the usefulness of both screening measures, the medical history, and the self-exclusion form to distinguish between high-risk and low-risk populations of HCV-carrier blood-donor candidates in Mexico. STUDY DESIGN AND METHODS: From February 2002 to April 2003, 4174 consecutive candidates were enrolled in a prospective, nonrandomized and comparative study. In total, 4158 candidates were included in the analysis and divided in two groups: Group A consisted of 3101 accepted donors and Group B consisted of 1057 deferred donors according to a complete medical history and self-exclusion form. The only exclusion criteria was the lack of a signed consent form to enter the study. All candidates from both groups underwent anti-HCV detection by third-generation enzyme immunoassay (EIA). Those who had either a positive or gray-zone signal-to-cutoff ratio underwent polymerase chain reaction and a second EIA test. If the second EIA test resulted in either a positive or gray-zone signal-to-cutoff ratio, a recombinant immunoblot assay test was performed. The chi-square test was used for statistical analysis, and a p value less than 0.05 was considered significant. RESULTS: Anti-HCV prevalence by the EIA method was as follows: 0.61 percent for Group A and 1.32 percent for Group B (p = 0.0243); whereas with recombinant immunoblot assay the prevalence was 0.19 percent for Group A and 0.47 percent for Group B (p = 0.1265). When we analyzed the polymerase chain reaction test results, the prevalence in Group A was 0.10 percent (95% confidence interval, 0.089-0.110) and in Group B was 0.47 percent (95% confidence interval, 0.439-0.500) (p = 0.0159). CONCLUSIONS: The medical history of blood donors in conjunction with serologic screening tests helps to improve blood transfusion safety. This measure is recommended in blood banks of those countries where NAT is still unaffordable.