Consenso argentino en gestión efectiva de clínicas de anticoagulación para uso de antagonistas de la vitamina K / Argentine consensus in effective management of anticoagulation clinics for the use of vitamin K antagonists

Resumen El tratamiento de un paciente anticoagulado con antagonistas de la vitamina K (AVK) sigue siendo un desafío, especialmente en regiones donde, por el costo, los dicumarínicos son todavía la alternativa más buscada a la hora de elegir un anticoagulante oral. Las clínicas de anticoagulación han demostrado ser la forma más eficiente y segura de evitar complicaciones trombóticas y hemorrágicas y de mantener al paciente en rango óptimo de tratamiento. Sin embargo, requieren de una adecuada infraestructura y personal capacitado para que funcionen eficientemente. En este consenso argentino se propone una serie de parámetros para la gestión efectiva de una clínica de anticoagulación. El objetivo es lograr una elevada calidad desde el punto de vista clínico-asistencial a través de un laboratorio de hemostasia de excelencia. Los criterios desarrollados en el documento fueron consensuados por un amplio grupo de expertos especialistas en hematología y en bioquímica de todo el país. Estos criterios deben adaptarse a la irregular disponibilidad de recursos de cada centro, pero siempre se los debe tener en cuenta a la hora de indicar el tratamiento anticoagulante con estas drogas. Tener en consideración estas premisas nos permitirá optimizar la atención del enfermo anticoagulado con AVK y de esta forma minimizar las intercurrencias trombóticas y hemorrágicas a las que está expuesto, para así honrar nuestra promesa de no dañar al paciente.

Abstract Treating an anticoagulated patient with vitamin K antagonists (VKA) remains a challenge, especially in areas where dicoumarins are still the first drug of choice due to the cost of other oral anticoagulants. Anticoagulation clinics have proven to be the most efficient and safe way to avoid thrombotic and hemorrhagic complications and to keep patients in optimal treatment range. However, they require adequate infrastructure and trained personnel to work properly. In this Argentine consensus we propose a series of guidelines for the effective management of the anticoagulation clinics. The goal is to achieve the excellence in both the clinical healthcare and the hemostasis laboratory for the anticoagulated patient. The criteria developed in the document were agreed upon by a large group of expert specialists in hematology and biochemistry from all over the country. The criteria presented here must always be considered when indicating VKA although they had to be adapted to the unequal reality of each center. Taking these premises into consideration will allow us to optimize the management of the anticoagulated patient with VKA and thus minimize thrombotic and hemorrhagic intercurrences, in order to honor our promise not to harm the patient.

Anexinas y pérdidas recurrentes de embarazo / Annexins and recurrent pregnancy loss

Las pérdidas de embarazo recurrentes (PER), afectan a la salud pública y comprometen en forma directa la calidad de vida de cientos de mujeres, con detrimento de su salud física y psíquica. Aproximadamente un 50% de las PER no se asocian a alguna de las etiologías conocidas, y por lo tanto se consideran idiopáticas. Recientemente se ha demostrado que la expresión de la anexina 5 (ANXA5), una proteína ubicada en la superficie trofoblástica, juega un papel fundamental en el mantenimiento del embarazo ya que cumple un rol como inmunomodulador y anticoagulante a nivel de la placenta. Algunos haplotipos genéticos de la ANXA5 se asocian a alteraciones en la expresión de este gen, como el haplotipo M2 que se vincula a una reducción en la expresión de la ANXA5. La presencia de dicho haplotipo se relaciona con los siguientes eventos del embarazo: PER, restricción del crecimiento fetal intrauterino, bajo peso al nacer, preclampsia y tromboembolismo pulmonar materno. Esta revisión describe la estructura, función y expresión genética de la ANXA5, así como también su posible implicancia en la PER.

Recurrent Pregnancy Loss (RPL) affects public health and directly compromises the quality of life of hundreds of women, with a detrimental effect on their physical and mental health. Approximately 50% of RPL are not associated to any of the currently known etiology and will be considered idiopathic. Recently, it has been demonstrated that the expression of annexin 5 (ANXA5), a protein found on the trophoblastic surface, plays a fundamental role in the development of pregnancy due to its immunomodulator and anticoagulant function at the placentary level. Some genetic haplotypes of ANXA5 are associated to alterations in the expression of this gene, such as haplotype M2 which is associated to a decrease in the expression of ANXA5. The presence of this haplotype is related to the following conditions occurring during pregnancy: RPL, foetal intrauterine growth restriction, low child weight at birth, preeclampsia and maternal pulmonary thromboembolism. This review describes the structure, function and genetic expression of ANXA5, as well as its possible implication in RPL.

Baja prevalencia de anticuerpos antifosfolípidos autoinmunes en enfermedades hepáticas / Low prevalence of autoimmune antiphospholipid antibodies in hepatic diseases

Antiphospholipid antibodies (aPL) have been associated with different diseases. They are defined as a large family of immunoglobulins (Ig) of either alloantibodies or autoantibodies. The autoimmune antibodies are associated with venous and/or arterial thrombosis, thrombocytopenia and recurrent fetal loss in the so-called antiphospholipid syndrome or in systemic lupus erythematosus. These antibodies are directed against proteins or phospholipid-protein complexes. On the contrary, antiphospholipid antibodies (alloantibodies) which are found in infectious diseases sera (syphilis, HIV, and other viral diseases), disappear with illness remission and are directed to phospholipids alone (particularly cardiolipin) and are not associated with thrombosis or recurrent fetal loss. However, the role and type of aPL found during hepatic diseases is still unclear. To investigate the prevalence of autoimmune aPL (IgG and IgM) during different hepatic diseases, we have studied 128 patients with hepatitis C virus, hepatitis B virus and hepatic autoimmune diseases without treatment as well as 40 healthy control subjects. We have used a specific ELISA kit, that uses a mixture of phospholipid instead of cardiolipin alone, and allows a better detection of aPL of the autoimmune type. Our results show that autoimmune aPL are not significantly increased in viral hepatic diseases (2%) or autoimmune diseases of the liver (3%) when compared to the control group (0%).