Función renal y nivel plasmático de dabigatrán en el valle, medido por un ensayo de trombina diluida / Renal function and plasma dabigatran level measured at trough by diluted thrombin time assay

El dabigatrán etexilato (inhibidor directo de trombina) es eficaz en la prevención tromboembólica en pacientes con fibrilación auricular. No requiere control rutinario de laboratorio, pero dada su eliminación renal, sería importante medirlo ante el deterioro de la función renal. Los objetivos del trabajo fueron verificar la calidad analítica del ensayo tiempo de trombina diluido para medición de la concentración plasmática (cc) de dabigatrán, correlacionar las cc con las pruebas básicas de coagulación tiempo de protrombina (TP) y tiempo de tromboplastina parcial activada (APTT) y evaluarlas de acuerdo al clearance de creatinina (CLCr). Se utilizaron muestras de plasma de 40 pacientes que recibían dabigatrán 150 (n = 19) o 110 (n = 21) mg/12 horas, colectadas 10-14 horas después de la última toma. Los ensayos de trombina diluida HemosIL DTI para la medición de dabigatrán, TP y APTT (IL), fueron realizados en coagulómetros fotoópticos ACL TOP 300 y 500 (IL). El DTI presentó coeficiente de variación intraensayo < 5.4% e interensayo < 6.0%, rango de linealidad 0-493 ng/ml; cc medidas en pacientes: mediana 83 (4-945) ng/ml. Individuos con CLCr en tercil inferior (< 46.1 ml/min) presentaron cc significativamente más elevadas, 308 (49-945), que los de tercilos medio, 72 (12-190), y superior, 60 (4-118) ng/ml. Las correlaciones cc vs. APTT o TP fueron moderadas, r2 = 0.59, -0.66, p < 0.0001, respectivamente. La prueba ensayada permitió cuantificar el nivel de dabigatrán plasmático tanto en pacientes con función renal normal como deteriorada, representando una herramienta útil en situaciones clínicas como deterioro de la función renal, pre cirugía o emergencias.

Dabigatran etexilate (direct thrombin inhibitor) is effective in preventing embolic stroke in patients with atrial fibrillation. It does not require laboratory control, but given the high renal elimination, its measurement in plasma is important in renal failure. The objectives of the study were to verify the analytical quality of the diluted thrombin time assay for measurement of dabigatran plasma concentration (cc), correlate cc with classic coagulation assays, prothrombin time (PT) and activated partial thromboplastin time (APTT), and evaluate them according to the creatinine clearance (CLCr). Forty plasma samples of patients (34 consecutive and 6 suspected of drug accumulation) receiving dabigatran at 150 (n = 19) or 110 (n = 21) mg/12 hours were collected. Blood samples were drawn at 10-14 hours of the last intake. Dabigatran concentration was determined by diluted thrombin time (HemosIl DTI, Instrumentation Laboratory (IL). PT and APTT (IL) were performed on two fotooptical coagulometers, ACL TOP 300 and 500 (IL). DTI presented intra-assay coefficient of variation < 5.4% and inter-assay < 6%, linearity range 0-493 ng/ml. Patients´ cc: median 83 (4-945) ng/ml. Individuals with CLCr in the lowest tertile (22.6-46.1 ml/min) showed significantly higher median cc: 308 (49-945), compared to the average 72 (12-190) and highest tertile, 60 (4-118) ng/ml. Correlation between cc and APTT or PT were moderate, r2 = 0.59 and -0.66, p < 0.0001, respectively. DTI test allowed us to quantify plasma dabigatran levels, both in patients with normal or altered renal function, representing a useful tool in clinical situations such as renal failure, pre surgery or emergencies.

Hemodiálisis para remover el anticoagulante dabigatrán en situaciones de urgencia / Hemodialysis to remove anticoagulant dabigatran during emergencies

El dabigatrán es un nuevo inhibidor directo de la trombina, de administración oral, empleado para la prevención de eventos tromboembólicos en pacientes con fibrilación auricular no valvular. A diferencia de la warfarina, no se dispone de un antídoto conocido. La hemodiálisis ha sido sugerida como un método para remover el dabigatrán y reducir el efecto anticoagulante. Se presenta el caso de un paciente con antecedente de fibrilación auricular y medicado con dabigatrán, que fue admitido en el hospital para una cirugía abdominal de urgencia. A las seis horas de la última dosis recibida, los estudios de coagulación mostraban alteración. Ante la falta de antídoto para revertir los efectos, se decidió realizar hemodiálisis. Luego de tres horas de diálisis los parámetros de coagulación tendieron a normalizarse y el paciente fue operado sin presentar hemorragias anormales durante la cirugía o en el postoperatorio.

Dabigatran is an oral anticoagulant from the class of the direct thrombin inhibitors, indicated for prevention of thromboembolic events in patients with non valvular atrial fibrillation. Unlike warfarin, dabigatran has no known antidote. Hemodialysis has been suggested as a method for removing dabigatran and thereby reducing its anticoagulant effect. We report the case of a patient with a known history of atrial fibrillation, treated with dabigatran, who was admitted for emergency abdominal surgery. At six hours after the last dose received, coagulation studies were altered. In absence of an antidote to reverse its effects, it was decided to perform hemodialysis. After three hours of dialysis coagulation parameters were improved and the patient underwent surgery without showing abnormal bleeding during surgery or in the postoperative period.

Changes in Plasma Levels of Natural Anticoagulants in Disseminated Intravascular Coagulation: High Prognostic Value of Antithrombin and Protein C in Patients with Underlying Sepsis or Severe Infection

BACKGROUND: Dysfunctional natural anticoagulant systems enhance intravascular fibrin for mation in disseminated intravascular coagulation (DIC), and plasma levels of natural anti coagulants can be used in the diagnosis and prognosis of DIC. Herein, the diagnostic value of 4 natural anticoagulants was assessed, and the prognostic value of antithrombin and protein C were validated in a large population. METHODS: Part 1 study included 126 patients with clinically suspected DIC and estimated plasma levels of 4 candidate anticoagulant proteins: antithrombin, protein C, protein S, and protein Z. Part 2 comprised 1,846 patients, in whom plasma antithrombin and protein C levels were compared with other well-known DIC markers according to the underlying dis eases. The 28-day mortality rate was used to assess prognostic outcome. RESULTS: Antithrombin and protein C showed higher areas under the ROC curve than pro tein S and protein Z. In part 2 of the study, antithrombin and protein C levels significantly correlated with DIC score, suggesting that these factors are good indicators of DIC severity. Antithrombin and protein C showed significant prognostic power in Kaplan-Meier analyses. In patients with sepsis/severe infection, antithrombin and protein C showed higher hazard ratios than D-dimer. Platelet count showed the highest hazard ratio in patients with hemato logic malignancy. In patients with liver disease, the hazard ratio for antithrombin levels was significantly high. CONCLUSIONS: Decreased plasma anticoagulant levels reflect florid consumption of the phys iologic defense system against DIC-induced hypercoagulation. Plasma antithrombin and protein C levels are powerful prognostic markers of DIC, especially in patients with sepsis/severe infection.

Clinical profile, common thrombophilia markers and risk factors in 85 young Indian patients with arterial thrombosis / Perfil clinico, marcadores comuns de trombofilia e fatores de risco em 85 pacientes indianos jovens com trombose arterial

CONTEXT AND OBJECTIVE: Arterial thrombosis may occur consequent to hereditary thrombophilia and increased lipoprotein(a) [Lp(a)] and fibrinogen. Our aim was to study the prevalence of common thrombophilia markers in 85 consecutive cases of arterial thrombosis. DESIGN AND SETTING: A retrospective study was conducted from 85 consecutive young patients treated as outpatients or admitted due to stroke or myocardial infarction at a tertiary care hospital. METHODS: Eighty-five Indian patients (age < 45 years) presenting ischemic stroke (n = 48) or myocardial infarction (n = 37) and 50 controls were studied for seven thrombophilia markers including antithrombin (AT), factor V, protein C, protein S, activated protein C resistance (APC-R), fibrinogen and Lp(a). Functional assays for protein C, protein S, factor V and APC-R were performed using clotting-based methods. Semi-quantitative estimation of fibrinogen was done using Clauss's method and Lp(a) using immunoturbidimetry. Statistical analysis was done using the Epi Info 6 software. RESULTS: Thirty-three samples (38.8%) tested positive for one or more thrombophilia markers. The three commonest abnormalities were elevated Lp(a) (20%), fibrinogen (17.6%) and low APC-R (14.2%). Low levels of protein C, protein S and AT were present in 4.7, 9.4 and 7% of the patients, respectively. Overall, the risk factor profile was: smoking (33%), positive family history (15.3%), hyperlipidemia (7%), hypertension, diabetes mellitus and obesity (2.3% each). CONCLUSIONS: An association was found between low levels of protein C, protein S and AT and arterial thrombosis, but only elevated fibrinogen levels, smoking, positive family history and hyperlipidemia showed statistical significance. .

CONTEXTO E OBJETIVO: Trombose arterial pode ocorrer em consequência de trombofilias hereditárias e de lipoproteína (a) [Lp (a)] e fibrinogênio aumentados. Nosso objetivo foi estudar a predominância de marcadores comuns da trombofilia em 85 casos consecutivos de trombose arterial. TIPO DE ESTUDO E LOCAL: Um estudo retrospectivo foi realizado sobre 85 pacientes jovens tratados consecutivamente no ambulatório ou admitidos por infarto do miocárdio ou acidente vascular cerebral (AVC) num hospital de cuidado terciário. MÉTODOS: Oitenta e cinco pacientes indianos (idade < 45 anos) que se apresentaram com AVC isquêmico (n = 48) ou infarto do miocárdio (n = 37) e 50 controles foram estudados para sete marcadores de trombofilia que incluíram antitrombina (AT), fator V, proteína C, proteína S, resistência ativada da proteína C (APC-R), fibrinogênio e Lp (a). Os ensaios funcionais da proteína C, proteína S, fator V e APC-R foram executados por métodos baseados em coagulação. A avaliação semiquantitativa do fibrinogênio foi feita pelo método de Clauss e a Lp(a) por imunoturbimetria. A análise estatística foi feita pelo software Epi Info 6. RESULTADOS: Trinta e três amostras (38.8%) foram positivas para um ou vários marcadores do trombofilia. As anomalias mais comuns foram Lp (a) (20%), fibrinogênio (17.6%) e APC-R (14.2%) elevados. Baixos níveis da proteína C, proteína S e AT foram detectados em 4.7%, 9.4% e 7% dos pacientes, respectivamente. Globalmente, os perfis dos fatores de risco foram: fumo (33%), antecedentes familiares positivos (15.3%), hiperlipidemia (7%), hipertensão, diabetes mellitus e obesidade (2.3% cada). CONCLUSÕES: Uma associação foi encontrada entre baixos níveis de proteína C, proteína S, AT e trombose arterial, ...

Prognostic value of plasma pro-adrenomedullin and antithrombin levels in neonatal sepsis

Neonatal sepsis is one of the major causes of morbidity and mortality in neonates. Proper diagnosis and management of neonatal septicemia can markedly affect prognosis of neonatal sepsis. In sepsis serum pro-Adrenomedullin level [pro-ADM] was known to be increased while Anti thrombin is rapidly depleted as a result of decreased synthesis, increased destruction, and enhanced clearance. The aim of this study was to clarify the prognostic value of serum Pro-ADM and Anti thrombin level in neonatal sepsis. 40 full term neonates with sepsis were enrolled in this study including 20 cases with mild sepsis and 20 cases with severe sepsis. They were admitted to the neonatal intensive care unit, they included 26 males and 14 females with a mean birth weight of 3.2 +/- 0.26 kg. Twenty healthy full term neonates of matched age and sex served as a control group. Serum levels of Pro ADM and Antithrombin were measured in all patients and control group. Serum Pro ADM level was significantly higher in neonates with sepsis than control group, was significantly higher in severe than mild sepsis and was significantly higher in the unsurvived cases. Antithrombin concentrations were significantly lower in neonates with sepsis than control group, significantly lower in severe than mild sepsis and significantly lower in neonates with sepsis who died than who survived. In conclusion, higher pro-ADM and lower initial AT levels in neonatal sepsis are associated with severe disease and increased risk of mortality