Trombocitopenia neonatal: Revisión. I. Definiciones, diagnóstico diferencial, causas, trombocitopenias inmunes / Neonatal thrombocytopenia: A review. I. Definitions, differential diagnosis, causes, immune thrombocytopenia

La trombocitopenia, definida como recuento plaquetario inferior a 100 x 109/l, es un hallazgo muy frecuente en el período neonatal, que ocurre, en especial, en niños críticamente enfermos y en prematuros. Sus causas son múltiples: puede deberse tanto a enfermedades del niño como a otros factores involucrados en la interrelación niño-placenta-madre. En este primer artículo, se enumeran las causas de trombocitopenia; se plantea el enfoque diagnóstico frente a un neonato trombocitopénico y se describen detalladamente las distintas entidades correspondientes a trombocitopenias de etiología inmune. Se presentan los diferentes mecanismos causales y se revisan las distintas características de la trombocitopenia secundaria a trombocitopenia inmune materna y de la trombocitopenia neonatal aloinmune. Se describen las diversas estrategias terapéuticas disponibles para cada una de ellas, tanto para su manejo posnatal como para el prenatal. Se enfatiza sobre la gravedad de la enfermedad y las serias complicaciones y secuelas asociadas a la trombocitopenia neonatal aloinmune

Thrombocytopenia, defined as a platelet count below 100 x 109/L, is a very common finding in the neonatal period, especially in critically ill infants and preterm newborns. Its causes are multiple: it may be due both to pediatric conditions and to other factors involved in the fetal-placental-maternal interface. This initial article describes the causes of thrombocytopenia, proposes a diagnostic approach to manage a thrombocytopenic newborn infant, and provides a detailed description of the different conditions corresponding to thrombocytopenia of immune etiology. It also describes the different causative mechanisms and reviews the varying characteristics of thrombocytopenia secondary to maternal immune thrombocytopenia and neonatal alloimmune thrombocytopenia. The different treatment approaches to each of the different conditions are described both for their pre- as well as their postnatal management. The severity of thrombocytopenia and the serious complications and sequelae associated with the neonatal alloimmune thrombocytopenia are highlighted.

Successful management of neonatal alloimmune thrombocytopenia in the second pregnancy: a case report / Sucesso no manejo da trombocitopenia aloimune neonatal na segunda gestação: relato de caso

Neonatal alloimmune thrombocytopenia is a serious disease, in which the mother produces antibodies against fetal platelet antigens inherited from the father; it is still an underdiagnosed disease. This disease is considered the platelet counterpart of the RhD hemolytic disease of the fetus and newborn, yet in neonatal alloimmune thrombocytopenia the first child is affected with fetal and/or neonatal thrombocytopenia. There is a significant risk of intracranial hemorrhage and severe neurological impairment, with a tendency for earlier and more severe thrombocytopenia in subsequent pregnancies. This article reports a case of neonatal alloimmune thrombocytopenia in the second pregnancy affected and discusses diagnosis, management and the clinical importance of this disease.

A púrpura trombocitopênica neonatal aloimune é uma doença grave, na qual a mãe produz anticorpos contra antígenos plaquetários fetais herdados do pai, e é ainda subdiagnosticada na prática clínica. É considerada o equivalente plaquetário da doença hemolítica do recém-nascido, com a diferença que o primeiro filho é afetado, apresentando trombocitopenia fetal e/ou neonatal. Há risco significativo de hemorragia intracraniana e sequelas neurológicas graves, com tendência a trombocitopenia mais grave e mais precoce nas gestações subsequentes. Este artigo relata um caso de trombocitopenia aloimune neonatal na segunda gestação afetada e discute diagnóstico, manejo e importância clínica dessa doença na prática clínica.