C1-inhibitor treatment in patients with severe complement-mediated autoimmune hemolytic anemia.

Complement-mediated (CM) autoimmune hemolytic anemia (AIHA) is characterized by the destruction of red blood cells (RBCs) by autoantibodies that activate the classical complement pathway. These antibodies also reduce transfusion efficacy via the lysis of donor RBCs. Because C1-inhibitor (C1-INH) is an endogenous regulator of the classical complement pathway, we hypothesized that peritransfusional C1-INH in patients with severe CM-AIHA reduces complement activation and hemolysis, and thus enhances RBC transfusion efficacy.

A national Transfusion Register of Irregular Antibodies and Cross (X)-match Problems: TRIX, a 10-year analysis.

Background: The Transfusion Register of Irregular Antibodies and Cross-match Problems (TRIX) is a unique national database in the Netherlands that was launched in 2007. Transfusion laboratories register the presence of irregular RBC alloantibodies for their patients and can consult the database for information that is relevant for pretransfusion testing, unknown in their own laboratory information system.

Study Design And Methods: Data from the TRIX database 10 years after implementation have been analyzed to demonstrate the added value of TRIX for transfusion practice.

Plasma thrombopoietin levels as additional tool in clinical management of thrombocytopenic neonates.

Plasma thrombopoietin (Tpo) levels distinguish thrombocytopenia resulting from increased platelet destruction or decreased platelet production. We investigated whether measuring plasma Tpo levels in thrombocytopenic newborns is of diagnostic value to establish the underlying mechanism of thrombocytopenia.Tpo levels were measured with in-house developed ELISA in samples referred to our center because of thrombocytopenia noticed in the first 10 days of life.

Complement deposition in autoimmune hemolytic anemia is a footprint for difficult-to-detect IgM autoantibodies.

In autoimmune hemolytic anemia autoantibodies against erythrocytes lead to increased clearance of the erythrocytes, which in turn results in a potentially fatal hemolytic anemia. Depending on whether IgG or IgM antibodies are involved, response to therapy is different. Proper identification of the isotype of the anti-erythrocyte autoantibodies is, therefore, crucial.

[Ceftriaxone-induced immune haemolytic anaemia and multi-organ failure].

Background: Drug-induced immune haemolytic anaemia (DIIHA) is caused by various drugs or their metabolites. Cephalosporins are associated with haemolytic anaemia but multi-organ failure is rarely described.

Case Description: We report the case of a 57-year-old female who was diagnosed with neuroborreliosis and treated with ceftriaxone.

Anti-Emm in a pregnant patient--case report.

A 23-year-old primigravida of North African origin presented with a positive antibody screen at booking at 15 weeks of gestation. An antibody to a high-frequency antigen (HFA) of unknown identity was detected, which was reactive with the red blood cells of the father. This led to several challenges including antibody identification, clinical monitoring to detect signs of haemolytic disease of the foetus and newborn (HDFN) and compatible blood in case perinatal transfusion was needed.

Postnatal outcome in neonates with severe Rhesus c compared to rhesus D hemolytic disease.

Background: Neonates with Rhesus c (Rh c) hemolytic disease of the fetus and newborn (HDFN) are often managed in the same way as neonates with Rhesus D (Rh D) HDFN, although evidence to support this policy is limited. The objective of this study was to evaluate neonatal outcome in severe Rh c HDFN compared to Rh D HDFN.

Study Design And Methods: A retrospective study of (near-)term neonates with severe Rh c (n = 22) and Rh D HDFN (n = 103; without additional antibodies) admitted to the Leiden University Medical Center between January 2000 and October 2011 was conducted.

Superior effect of intravenous anti-D compared with IV gammaglobulin in the treatment of HIV-thrombocytopenia: results of a small, randomized prospective comparison.

This small, prospective, randomized study compared increases in platelet counts and duration of response after intravenous gammaglobulin (IVIG) and IV anti-D in patients with HIV-related thrombocytopenia (HIV-TP). Nine Rh+, nonsplenectomized HIV-positive patients with thrombocytopenia were treated sequentially, in random order, with IVIG and IV anti-D in a cross over design, receiving each therapy for 3 months. Peak platelet counts and duration of effect after each treatment were compared.

Blood group does not correlate with disease severity in patients with Fabry disease (alpha-galactosidase A deficiency).

Blood groups B and P1 are substrates for the lysosomal enzyme alpha-galactosidase A. Therefore, patients with alpha-Gal A deficiency and blood groups B or P1 may exhibit more severe disease. In 48 Fabry patients distribution of blood group was not different from that in the Dutch population.

Fetal and neonatal thrombopoietin levels in alloimmune thrombocytopenia.

Thrombopoietin (Tpo) is the main hematopoietic growth factor for platelet production. Plasma Tpo levels in autoimmune thrombocytopenic patients are normal or slightly elevated. Although thrombocytopenia exists, Tpo levels are not increased because the produced megakaryocytes and platelets can bind circulating Tpo, thereby normalizing Tpo levels.

Three parameters, plasma thrombopoietin levels, plasma glycocalicin levels and megakaryocyte culture, distinguish between different causes of congenital thrombocytopenia.

Fourteen children with congenital thrombocytopenia were analysed in order to unravel the mechanisms underlying their thrombocytopenia and to evaluate the value of new laboratory tests, namely measurement of plasma thrombopoietin (Tpo) and glycocalicin (GC) levels and analysis of megakaryocytopoiesis in vitro. Three groups of patients were included. The first group (n = 6) was diagnosed with congenital amegakaryocytic thrombocytopenia.

Plasma thrombopoietin levels in patients with chronic renal failure.

Introduction: Thrombopoietin (Tpo) is the most important regulator of thrombocytopoiesis. The main sites of Tpo production are the liver and the kidney produce Tpo. In the current study, the influence of renal failure on overall Tpo production was evaluated.

The potential role of thrombopoietin in idiopathic thrombocytopenic purpura.

Thrombopoietin (TPO) plays a central role in the pathogenesis of idiopathic thrombocytopenic purpura (ITP), as it does in other immune-mediated thrombocytopenias. Because TPO is bound and internalized by platelets, it is destroyed together with platelets at an accelerated rate in the macrophage system. Because the spleen acts as a TPO sink, compensation of the decreased platelet count by an increased production in the bone marrow is insufficient.

The role of thrombopoietin in post-operative thrombocytosis.

Thrombopoietin (Tpo), the main regulator of thrombocytopoiesis, is a probable candidate to play a role in the increase in platelet counts that is frequently seen after surgery. In the current study, serial blood samples of patients that underwent major surgery were analysed with respect to Tpo kinetics, platelet turnover and inflammatory cytokines. Platelet Tpo content and plasma Tpo levels rose before platelet counts increased, suggesting that Tpo was indeed responsible for the elevation in platelet counts.

In multiple myeloma increased thrombopoietin (Tpo) production may be involved in the maintenance of platelet production.

In multiple myeloma (MM), suppression of haematopoiesis occurs as a result of expansion of malignant cells in the bone marrow. Thrombopoietin (Tpo) levels in patients with impaired platelet production are generally found to be highly elevated. To examine the circulating Tpo levels in patients with MM, Tpo levels were measured in 50 serum samples from 34 patients.

Analysis of the kinetics of TPO uptake during platelet transfusion.

Background: It has been shown in several studies that platelets play a role in the removal of TPO from the circulation. For instance, in vitro studies have shown that platelets can bind and internalize TPO, and transfusion studies have shown that the concentration of circulating TPO decreased after platelet transfusion. In the current study, the in vivo kinetics of plasma TPO levels and TPO uptake by transfused platelets is analyzed in more detail.