Pruebas del coagulograma y componentes de la hemostasia. Utilidad para diagnosticar las diátesis hemorrágicas / Tests of coagulation and hemostasis components. Usefulness for diagnosing hemorrhagic diathesis

El coagulograma comprende un conjunto de pruebas que exploran la participación de todos los componentes de la hemostasia: endotelio vascular, actividad plaquetaria, factores plasmáticos y fibrinolíticos. Con frecuencia, la ejecución de estas pruebas resulta compleja para el personal técnico, por lo que la profundización en el conocimiento e interpretación de los resultados de cada una de estas, debe redundar en el fortalecimiento y preparación de los profesionales de la salud. En el presente trabajo se describen las principales pruebas del coagulograma convencional, el principio y los valores de referencia de cada una, así como las posibles enfermedades de acuerdo con la alteración del sistema hemostático que corresponde a la alteración del coagulograma, con el objetivo de brindarle al médico una información básica para la correcta ejecución y adecuada interpretación de los resultados

Coagulogram comprises a set of tests, which explore the participation of all components of hemostasia: vascular endothelium, platelet activity, plasma and fibrinolytic factors. Often, the technical staff finds complex to do these tests, so deepening knowledge, understanding, and interpreting the results of each of these tests should result in strengthening and training of health professionals. This paper describes the main conventional coagulation tests, the beginning and the reference values of each of them, and the possible diseases according to the alteration of the hemostatic system corresponding to the alteration of coagulation, with the aim of providing medical background information for the proper performance and proper interpretation of results

Abnormal glucose tolerance in beta-thalassemia patients: possible risk factors

In beta-thalassemia major, transfusional iron overload lead to impaired glucose tolerance [IGT] then diabetes mellitus [DM]. The pathogenetic mechanisms leading from siderosis to diabetes are still poorly understood. To assess the glycometabolic status in transfusion-dependent Egyptian beta-thalassemia patients and to evaluate the possible risk factors for abnormal glucose tolerance [AGT] in them. Oral glucose tolerance test [OGTT] was done to 54 multi-transfused thalassemic patients, aged 10.1-25.1 years, and 28 age-matched normal controls with measuring serum insulin level at 0, 120 minutes. Insulin sensitivity and insulin release index were calculated according to the homeostasis model assessment [HOMA], fasting insulin glucose ratio [FIG], insulin sensitivity index for glycemia [ISl gly] and fasting insulin resistance index [FIRI]. Indicator of iron overload and liver status were recorded. Thirteen patients [24.1%] were diagnosed to have variable degrees of AGT; either DM in 6 cases [11.1%] or IGT in 7 cases [13%] and normal glucose tolerance [NGT] was in 41 patients [75.9%]. Cases with AGT had significant higher mean postprandial insulin, FIRI and HOMA insulin resistance [IR], p=0.0001 for all, and significant lower mean HOMA beta-cell, p=0.007 if compared to the cases with NGT. By stepwise logistic regression analysis, the total blood taken per year was the independent risk factor for abnormal glucose tolerance, OR=0.49, p=0.03. Serum ferritin was higher in cases with AGT compared to cases with NGT, p= 0.04 and it correlated with fasting insulin level, FIRI and HOMA IR, p=0,003,0.001, 0.001 and r=0.4, 0.5, 0.5 respectively. Chronic hepatitis C was detected in 12 patients [92.3%] with AGT. Abnormal glucose tolerance is common in multi-transfused beta-thalassemia patients, which could be attributed to impaired beta-cell function, along with insulin resistance

Haematophagous arthropod saliva and host defense system: a tale of tear and blood

A saliva de artrópodes hematófagos é rica em moléculas com funções diversas que mediam uma alimentação sangüínea bem sucedida. Estas moléculas agem não apenas como armas contra a resposta hemostática, inflamatória e imunológica do hospedeiro funcionando também como ferramentas para o estabelecimento de patógenos. Parasitas, vírus e bactérias aproveitando-se deste arsenal dos vetores adaptaram-se facilitando seu estabelecimento no hospedeiro. Hoje, várias moléculas salivares foram identificadas e caracterizadas como novos alvos para o desenvolvimento de vacinas futuras. Neste trabalho, centramos em informação recente sobre a saliva de vetores e as moléculas responsáveis por modificar a resposta hemostática e imunológica assim como seu papel na transmissão de doenças.

Anticuerpos antifosfolípidos: aspectos inmunoquímicos y patogénicos / Antiphospholipid antibodies: immunochemistry and pathogenetic features

Los anticuepos antifoslípidos (AFL), incluyen varios tipos como los que se describieron inicialmente en las enfermedades infecciosas. Además, se conocen ahora otros AFL como son los reactivos contra cardiolipina o los denominados anticoagulante de lupus. Estos AFL pueden ser isotipo IgG,M o A, la mayor relevancia actualmente se confiere al isotipo IgG. La especificidad parece estar dirigida a fosfolípidos con carga negativa y juega un papel importante a Apolipoproteína H como cofactor o integrante del complejo antigénico reconocido por una proporción de estos AFL. El impacto patogénico de estos AFL no se ha definido con certeza, pero la evidencia muestra intervención potencial en las fases de la coagulación dependientes de fosfolípidos