Trombocitopenia por agregados plaquetarios / Thrombocytopenia by aggregated platelet: case report

Introducción: la pseudotrombocitopenia inducida por EDTA (ácido etilendiamino tetraacético) es un fenómeno de aglutinación de plaquetas que se presenta in vitro, mediado por anticuerpos anti-plaquetarios de tipo IgG, IgA o IgM dirigidos contra el complejo glucoproteínico IIb/IIIa de la membrana plaquetaria. Caso clínico: presentamos un caso clínico de una paciente de 59 años de edad sometida a recambio valvular aórtico; clínicamente con evolución favorable durante el periodo posquirúrgico, sin embargo, en estudios de control se registra trombocitopenia severa, lo que llevo a cuestionar el uso de anticoagulantes y la necesidad de transfusión de plaquetas. Al realizar estudios complementarios se encontró agregados plaquetarios en el frotis de sangre periférica, posteriormente se realizó recuento seriado de plaquetas y comparación del histograma plaquetario, catalogando el caso como pseudotrombocitopenia. Conclusión: La trombocitopenia por agregados plaquetarios es una condición de baja incidencia (0.07% a 0.1%). Se debe a la agregación de plaquetas in vitro asociada al uso de anticoagulantes, frecuentemente etilendiaminotetraacético (EDTA), en el presente caso también se asoció al uso de citrato de sodio. Este problema no se asocia a sangrado, sin embargo su desconocimiento pudo haber llevado a realizar procedimientos diagnósticos y terapéuticos innecesarios

Introduction: EDTA (ethylenediamine tetraacetic acid) ­induced by pseudothrombocytopenia is a platelet agglutination phenomenon that occurs in vitro, which are mediated by anti-platelet antibodies of the IgG, IgA or IgM type directed against the glycoprotein complex IIb / IIIa of the platelet membrane . Clinical case: This is a clinical case of a 59-yearsold patient undergoing aortic valve replacement, clinically with a favorable evolution during the postoperative period, however, in control studies, severe thrombocytopenia was recorded, which led to questioning the use of anticoagulants and the need for platelet transfusion. When carrying out complementary studies, aggregated platelet were found in the peripheral blood smear, later, a serial platelet count and comparison of the platelet histogram were performed, classifying the case as pseudotrombocytopenia. Conclusion: Thrombocytopenia due to aggregated platelet is a low incidence condition (0.07% to 0.1%). It is due to the aggregation of platelets in vitro associated with the use of anticoagulants [frequently ethylenediamine tetra acetic (EDTA)]; in the present case it was also associated with the use of sodium citrate. This problem is not associated with bleeding; however its lack of knowledge leads to unnecessary diagnostic and therapeutic procedures.

Effects of additives in blood collection tubes on testing the alcohol concentration in blood samples / 法医学杂志

OBJECTIVE@#To discuss blood collection tubes with different additives and their effects on the testing results of alcohol concentration in blood samples.@*METHODS@#Blood samples from 10 volunteers were collected 2 hours after drinking with seven different types of disposable vacuum blood collection tubes, including ordinary tube without anticoagulant, coagulant tube, separating gel-coagulant tube, sodium citrate (1:4) tube, sodium citrate (1:9) tube, sodium citrate (9:1) tube and EDTA-K2 tube. The alcohol concentrations in these blood samples were analyzed by headspace gas chromatography.@*RESULTS@#The concentration testing results of the same blood samples in different types of tubes were different from one to another. The sequence was as follows: separating gel-coagulant tube > coagulant tube > ordi- nary tube without anticoagulant > EDTA-K2 tube> sodium citrate (1:9) tube> sodium citrate (1:4) tube, whereas the results of the same blood sample in sodium citrate (1:9) tube and sodium citrate (9:1) tube showed no obvious difference.@*CONCLUSION@#It is better to collect a suspicious drunk driver's blood sam- ple using a disposable vacuum blood collection tube, with the EDTA-K2 tube being preferred.

A prospective six-week randomized controlled trial on the efficacy and safety of sodium bicarbonate, citric acid, sodium citrate, and tartaric acid compound compared to potassium citrate in the dissolution of renal stones

OBJECTIVE: To determine the efficacy and safety of sodium bicarbonate, citric acid, sodium citrate, and tartaric acid (compound drug) in comparison to potassium citrate in the treatment of kidney stones. METHODS: Prospective randomized controlled trial of patients with kidney stones recruited from February to October 2011 at Out-patient Department was conducted. Ninety subjects, consented and eligible, were enrolled in this study. Random allocation of subjects into two groups was done using computer generated randomization. Subjects assigned to group I were treated with the compound drug(12 grams/day); while group II subjects were given potassium citrate(60mEq/day) for 6 weeks. Urinary pH levels were examined weekly and the effect of medical treatment on stone size changes was evaluated by ultrasonography every two weeks in the six-week treatment period. Intention to treat analysis was done with 95% confidence level(CI). Statistical analysis of results was determined using analysis of variance (ANOVA) with multiple repeated measures for between group urinary pH changes and chi square for between groups difference in stone size changes. RESULTS: A total of 74 subjects completed the study with a dropout rate of 18%, which was mainly due to geographic and financial reasons. Demographic and baseline stone characteristics of both groups were not significantly different. Treatment outcome between the two groups based on stone size changes (in general and both radiolucent and radioopaque stones subgroups) did not show any significant statistic difference. The pH level changes over six-week treatment period between the two groups showed a total mean pH difference of 0.445, (95% CI: 0.213, 0.677), which was statistically significant (P CONCLUSION:  Urinary alkalinization with sodium bicarbonate, citric acid, sodium citrate, and tartaric acid is a well-tolerated and highly effective treatment resulting in dissolution of non-obstructing kidney stones and is comparable to the gold standard potassium citrate.