A prospective study to assess the predictive value for hereditary spherocytosis using five laboratory tests (cryohemolysis test, eosin-5'-maleimide flow cytometry, osmotic fragility test, autohemolysis test, and SDS-PAGE) on 50 hereditary spherocytosis families in Argentina.

This prospective study was carried out to assess the usefulness of five laboratory tests in the diagnosis of hereditary spherocytosis (HS), based on the correlation of erythrocyte membrane protein defects with clinical and laboratory features, and also to determine the membrane protein deficiencies detected in Argentina. Of 116 patients and their family members tested, 62 of them were diagnosed to have HS. The specificity of cryohemolysis (CH) test was 95.2%, and its cut-off value to distinguish HS from normal was 2.8%. For flow cytometry, cut-off points of 17% for mean channel fluorescence (MCF) decrease and 14% coefficient of variation (CV) increase showed 95.9% and 92.2% specificity, respectively. Both tests showed the highest percentages of positive results for diagnosis. Either CH or flow cytometry was positive in 93.5% of patients. In eight patients, flow cytometry was positive only through CV increase. Protein defects were detected in 72.3% of patients; ankyrin and spectrin were the most frequently found deficiencies. The CV of the fluorescence showed significantly higher increases in moderate and severe anemia than in mild anemia (p = 0.003). Severity of anemia showed no other correlation with tests results, type of deficient protein, inheritance pattern, or neonatal jaundice. CH and flow cytometry are easy methods with the highest diagnostic accuracy. Simultaneous reading of mean channel fluorescence (MCF) decrease and CV increase improve diagnostic usefulness of flow cytometry. This test seems to be a reliable predictor of severity. The type of detected protein deficiency has no predictive value for outcome. Predominant ankyrin and spectrin deficiencies agree with reports from other Latin American countries.

Antibodies to hepatitis C and other viral markersin multi-transfused patients from Argentina.

BACKGROUND: The knowledge of transfusion-transmitted viral infections in Argentina is scarce. A regional study organized by the Pan American Health Organization let us asses the current status. OBJECTIVES: To estimate the prevalence of HCV, HBV and HIV infection in a population of multi-transfused Argentinean patients. STUDY DESIGN: Multi-center, cross sectional study of 504 patients from national referral institutions in Buenos Aires, who had received more than ten units of blood products in more than two occasions. Demographic and clinical data were collected using a standardized questionnaire. Blood samples were analyzed for a-HCV, a-HIV, HBsAg and a-HBcore. RESULTS: Patients belonged to five diagnostic categories: onco-hematology (309; 61.3%); hemophilia (96; 19%); acute blood loss (54; 10.7% ); hemoglobinopathies (35; 6.9%); and hemodialysis (5; 1% ); five patients (1%) had two of the previous conditions. Overall prevalence rates of viral markers were: a-HCV 9.3% (CI(95%): 6.7-12.0); a-HBcore 4.8% (CI(95): 2.8-6.7); a-HIV 1.2% (CI(95%): 0.14-2.2) and HBsAg 0.20%(CI(95%): 0.2-0.59). The highest prevalence rates were found among patients living with hemophilia (PLH). There was a significant statistical association (p < 10(-5), OR =78.8 [29.7-209.7]) between a-HCV infection and having been transfused before 1993, when screening blood donors for a-HCV became mandatory in our country. The subpopulation of patients exposed to transfusion before 1993 was conformed mostly by PLH (70.9%) and hemoglobinopathies (18.6%). In this subpopulation, we found a significant association (p < 10(Dot;), OR -40 [5.68-281.66]) between years of exposure to transfusion and a-HCV among the patients under the median age (21.95 years old); however, there was no association for those above the median age (p=0.111). CONCLUSION: a-HCV was found to be the most prevalent infection in the multi-transfused patient population under study. Most infected individuals were PLH, transfused before 1993. This study will provide support for further research aimed at improving blood safety in Argentina.

Evolución de las prestaciones de Aféresis en el Hospital Posadas / Apheresis evolution in Posadas Hospital

Se analiza la evolución de las presentaciones de Aféresis en nuestro servicio a la luz de un cambio actitudinal operado en un momento del desarrollo del mismo, alcanzando niveles de crecimiento importantes y una proyección aún mayor para el futuro inmediato, constituyendo un aporte para el arsenal terapéutico disponible para toda la comunidad médica.

Evolución de las prestaciones de Aféresis en el Hospital Posadas / Apheresis evolution in Posadas Hospital

Se analiza la evolución de las presentaciones de Aféresis en nuestro servicio a la luz de un cambio actitudinal operado en un momento del desarrollo del mismo, alcanzando niveles de crecimiento importantes y una proyección aún mayor para el futuro inmediato, constituyendo un aporte para el arsenal terapéutico disponible para toda la comunidad médica. (AU)