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Platelet Syndrome (platelet + syndrome)
Selected AbstractsSticky Platelet Syndrome: An Underrecognized Cause of Graft Dysfunction and Thromboembolic Complications in Renal Transplant RecipientsAMERICAN JOURNAL OF TRANSPLANTATION, Issue 7 2007A. S. Mühlfeld Sticky platelet syndrome (SPS) leads to hyperaggregabilty of platelets in response to physiologic stimuli. In this report we describe three patients with clinical symptoms of SPS after renal transplantation. The first patient developed an infarction of her transplant kidney with additional, subsequent renal microinfarctions. The second patient suffered multiple strokes and deep vein thrombosis with episodes of pulmonary embolism and ischemic bowel disease due to colonic microinfarctions. The third patient experienced a long episode of unexplained respiratory and graft dysfunction immediately after transplantation until therapy for SPS was initiated, at which point symptoms resolved quickly. Kidney transplant recipients with SPS may be at increased risk of developing thrombosis, given that most immunosuppressive drugs are known to induce either endothelial cell damage or augment platelet aggregation. All patients awaiting renal transplantation should be screened for a history of thrombosis and, if appropriate, tested for SPS. Affected patients should receive dose-adjusted acetylsalicylic acid. [source] COMMENTARY: Clinical proteomics in platelet research: challenges aheadJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 8 2010Á. GARCÍA See also Maynard DM, Heijnen HFG, Gahl WA, Gunay-Aygun M. The ,-granule proteome: novel proteins in normal and ghost granules in gray platelet syndrome. This issue, pp 1786,96. [source] Qualitative disorders of platelets and megakaryocytesJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 8 2005A. T. NURDEN Summary., Qualitative disorders of platelet function and production form a large group of rare diseases which cover a multitude of genetic defects that by and large have as a common symptom, excessive mucocutaneous bleeding. Glanzmann thrombasthenia, is enabling us to learn much about the pathophysiology of integrins and of how ,IIb,3 functions. Bernard,Soulier syndrome, an example of macrothrombocytopenia, combines the production of large platelets with a deficit or non-functioning of the major adhesion receptor of platelets, the GPIb-IX-V complex. Amino acid substitutions in GPIb,, may lead to up-regulation and spontaneous binding of von Willebrand factor as in Platelet-type von Willebrand disease. In disorders with defects in the MYH9 gene, macrothrombocytopenias are linked to modifications in kidney, eye or ear, whereas other inherited thrombocytopenias variously link a low platelet count with a propensity to leukemia, skeletal defects, learning impairment, and abnormal red cells. Defects of secretion from platelets include an abnormal , -granule formation as in the gray platelet syndrome (with marrow myelofibrosis), and of organelle biogenesis in the Hermansky,Pudlak and Chediak,Higashi syndromes where platelet dense body defects are linked to abnormalities of other lysosomal-like organelles including melanosomes. Finally, defects involving surface receptors (P2Y12, TP,) for activating stimuli, of proteins essential for signaling pathways (including Wiskott,Aldrich syndrome), and of platelet-derived procoagulant activity (Scott syndrome) show how studies on platelet disorders are helping unravel the pathways of primary hemostasis. [source] Probing platelet factor 4 ,-granule targetingJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 12 2004V. Briquet-Laugier Summary., The storage mechanism of endogenous secretory proteins in megakaryocyte ,-granules is poorly understood. We have elected to study the granule storage of platelet factor 4 (PF4), a well-known platelet ,-granule protein. The reporter protein green fluorescent protein (GFP), PF4, or PF4 fused to GFP (PF4-GFP), were transfected in the well-characterized mouse pituitary AtT20 cell line, and in the megakaryocytic leukemic DAMI cell line. These proteins were also transduced using a lentiviral vector, in human CD34+ cells differentiated into megakaryocytes in vitro. Intracellular localization of expressed proteins, and colocalization studies were achieved by laser scanning confocal microscopy and immuno-electronmicroscopy. In preliminary experiments, GFP, a non-secretory protein (no signal peptide), localized in the cytoplasm, while PF4-GFP colocalized with adrenocorticotropin hormone (ACTH)-containing granules in AtT20 cells. In the megakaryocytic DAMI cell line and in human megakaryocytes differentiated in vitro, PF4-GFP localized in ,-granules along with the alpha granular protein von Willebrand factor (VWF). The signal peptide of PF4 was not sufficient to specify ,-granule storage of PF4, since when PF4 signal peptide was fused to GFP (SP4-GFP), GFP was not stored into granules in spite of its efficient translocation to the ER-Golgi constitutive secretory pathway. We conclude that the PF4 storage pathway in ,-granules is not a default pathway, but rather a regular granule storage pathway probably requiring specific sorting mechanisms. In addition PF4-GFP appears as an appropriate probe with which to analyze ,-granule biogenesis and its alterations in the congenital defect gray platelet syndrome. [source] Sticky Platelet Syndrome: An Underrecognized Cause of Graft Dysfunction and Thromboembolic Complications in Renal Transplant RecipientsAMERICAN JOURNAL OF TRANSPLANTATION, Issue 7 2007A. S. Mühlfeld Sticky platelet syndrome (SPS) leads to hyperaggregabilty of platelets in response to physiologic stimuli. In this report we describe three patients with clinical symptoms of SPS after renal transplantation. The first patient developed an infarction of her transplant kidney with additional, subsequent renal microinfarctions. The second patient suffered multiple strokes and deep vein thrombosis with episodes of pulmonary embolism and ischemic bowel disease due to colonic microinfarctions. The third patient experienced a long episode of unexplained respiratory and graft dysfunction immediately after transplantation until therapy for SPS was initiated, at which point symptoms resolved quickly. Kidney transplant recipients with SPS may be at increased risk of developing thrombosis, given that most immunosuppressive drugs are known to induce either endothelial cell damage or augment platelet aggregation. All patients awaiting renal transplantation should be screened for a history of thrombosis and, if appropriate, tested for SPS. Affected patients should receive dose-adjusted acetylsalicylic acid. [source] Two-stage total hepatectomy and liver transplantation for acute deterioration of chronic liver disease: A new bridge to transplantationLIVER TRANSPLANTATION, Issue 4 2004Michael J. Guirl Two-stage total hepatectomy and liver transplantation has been reported for acute liver disease such as fulminant hepatic failure, primary graft failure, severe hepatic trauma, and spontaneous hepatic rupture secondary to hemolysis, elevated liver function tests, low platelets syndrome, and preeclampsia. This is the first report of patients with cirrhosis to undergo a 2-stage total hepatectomy and liver transplantation. From 1984 to 2002, our institution performed 2008 orthotopic liver transplantations. We identified 4 patients with chronic liver disease who underwent a 2-stage hepatectomy and liver transplantation. This is a retrospective review of these 4 patients and a review of the literature on this procedure. All 4 patients were young men with an age range of 29,31 years and had underlying cirrhosis as well as a previous transjugular intrahepatic portosystemic shunt (TIPS)procedure. Acute decompensation fulfilling Ringes' criteria for toxic liver syndrome secondary to an upper gastrointestinal bleed occurred in all patients. The approximate average time between hepatectomy and liver transplantation was 20 hours (range: 8,42 hours). In all cases, the explanted liver showed histological changes of acute hepatic necrosis within the background of cirrhosis. After hepatectomy, vasopressor requirements were well documented in 2 patients. For 1 patient, there was a clear improvement in their hemodynamic status. The mean hospital stay of the 4 patients was 63 days. All patients were discharged from the hospital and are alive and well with adequate liver function at 6 to 37 months follow-up. Two-stage total hepatectomy and liver transplantation may be a life-saving procedure in highly selected cirrhotic patients with acute hepatic decompensation and multiorgan dysfunction. (Liver Transpl 2004;10:564,570.) [source] | ||||||||||