Active clinical trials for "Thrombocytopenia"

Idiopathic thrombocytopenic purpura (ITP) is the most frequent auto-immune cytopenia. There is no specific biological marker and the diagnosis often results from the exclusion of other differential diagnoses, notably inherited thrombocytopenia. Recent studies have reported an original platelet destruction mechanism in ITP, by antibody-mediated desialylation of membrane proteins. The detection of platelet sialylation can be readily achieved using flow cytometry. This could provide a new biomarker of ITP, useful to ascertain a diagnosis of ITP and guide towards proper patient management.

This is a multi-center prospective observational descriptive study complemented by a retrospective chart review. Patients diagnosed with ITP and currently treated for ITP by a hematologist or hematologist-oncologist will be recruited from community-based clinics and academic/referral centers. They will be followed prospectively for a period of 12 months. At inception, participants' charts will also be reviewed from the date of enrollment retrospectively to the date of diagnosis or the previous 36 months, whichever is less.

Characterization of the genetic causes, and of the immunopathological clinical and biological manifestations in children with pediatric Evans syndrome included in a prospective national observational cohort of rare diseases.

The project was retrospectively undertaking by Qilu Hospital of Shandong University in China. In order to investigate the correlations between platelet indices, serum lipids and bleeding symptoms in ITP.

Preeclampsia (Pre-E) is a hypertensive disease of pregnancy with multi-system involvement that usually occurs in the second half of pregnancy. Pre-E occurs in 5% to 7% of U.S. pregnancies, and is the third-leading cause of U.S. maternal death. Improvements to the current diagnostic paradigm have been evaluated. However, no stand-alone diagnostic method has emerged that more accurately identifies women at risk for preeclampsia, warranting improvements in diagnosing Pre-E. This sample collection study will obtain serum and urine samples from pregnant women who present with clinical signs, symptoms, or conditions contributing to the suspicion of Pre-E. Samples will be used to evaluate and validate the performance of an assay intended to aid in assessing the risk of Pre-E.

The chronic immune thrombopenia is an autoimmune disease caused by B cells. These cells produce anti platelets and megakaryocytes antibodies. Some B cells, named regulatory B cells, are known to control other cells. Their action in chronic immune thrombopenia is actually unknown.

The purpose of this retrospective registry is to collect data about patients with acute HIT II (Heparin-induced Thrombocytopenia type II) which were treated with Lepirudin, Danaparoid, Argatroban or Fondaparinux. It is a main objective of this registry to mirror the daily routine in this indication in Germany.

Although Heparin-induced thrombocytopenia (HIT) is a rare complication of heparin treatment, it results in a high rate of morbidity and mortality, the cumulative rate of thrombosis recurrence, amputation and death approaching 52 % at one month if no specific treatment is initiated. It is therefore vital to diagnose HIT as early and as reliably as possible to permit appropriate management of this rare condition. During the acute phase of HIT, clinicians and biologists can only suspect this complication with a greater or lesser degree of confidence. Clinical data are not sufficiently sensitive or specific to confirm or refute thr diagnosis of HIT.

Thrombocytopenia (platelet count < 100,000/mL) occurs in approximately 15% of women with preeclampsia. Neuraxial analgesia is contraindicated in parturients with a coagulopathy; therefore, the platelet count(PC) is routinely checked prior to the initiation of neuraxial analgesia in women with preeclampsia/eclampsia. Catheter removal is also contraindicated in the presence of a coagulopathy. Some women have an acceptable PC at the initiation of neuraxial analgesia, but may become significantly more thrombocytopenic during labor and delivery. In a study of severely preeclamptic parturients, some with HELLP (H=hemolysis of red blood cells, EL=elevated liver enzymes, LP=low platelet count) syndrome, the admission PC correlated with the PC nadir. However, the natural progression of the PC has not been studied in women with mild preeclampsia. We hypothesize that women with mild preeclampsia or severe preeclampsia without HELLP syndrome, and whose admission PC is greater than 150,000/mL, will have a stable PC during the course of labor and delivery and do not require another PC check prior to initiation of neuraxial analgesia or removal of the epidural catheter. The purpose of this study is to determine the positive predictive value of an initial PC greater than 150,000/mL for maintaining a PC greater than 80,000/mL during labor and delivery.

Plasma histidine-rich glycoprotein (HRG) binds to platelets in the presence of zinc (1). This binding is totally blocked by a monoclonal antibody directed against platelet membrane CD36. Therefore, CD36 is assumed to carry the platelet binding site for HRG (2). Because CD36 also has a variety of other ligands, including polyanionic lipids, it is also possible that it contains the binding site for heparin (also polyanionic) and might be involve in the pathogenesis of heparin-induced thrombocytopenia. Demonstrating absent HRG or heparin binding to platelets lacking CD36 would confirm that the binding sites for either or both of these ligands are located on this membrane protein. Because 3% to 11% of healthy Japanese are reported to lack CD36 on their platelets, this population is a practical source of cells for examining the physiologic role(s) for CD36. Therefore, we will recruit blood donors from the Japanese community on the NIH campus. Their platelets will tested for the presence of CD36. Recruitment will be closed after two individuals have been identified whose platelets lack CD36 and who are willing to donate 30 cc of blood on 4 or 5 subsequent occasions for binding studies with radiolabeled HRG and heparin.