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Microangiopathic Hemolytic Anemia (microangiopathic + hemolytic_anemia)
Selected AbstractsEvaluation of eosin-5-maleimide flow cytometric test in diagnosis of hereditary spherocytosisINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 1p2 2010R. KAR Summary A flow cytometry-based test using eosin-5-maleimide (EMA) dye was used for diagnosis of hereditary spherocytosis (HS). The mean fluorescence intensiy (MFI) of EMA tagged erythrocytes is lower in HS than that in other hemolytic and nonhemolytic anemias. We enrolled 114 subjects comprising 20 confirmed HS, 20 suspected HS/hemolytic anemia (HA), 20 normal controls, 20 other hemolytic anemias [13 autoimmune hemolytic anemia, three congenital dyserythropoietic anemia (CDA), one pyruvate kinase deficiency, two microangiopathic hemolytic anemia], 18 microcytic anemia and 16 macrocytic anemia cases. All samples were subjected to flow cytometry as per standard protocol. The mean MFI of normal control subjects was 11 861.5 (SD 883.5) and of confirmed HS was 7949.3 (SD 1304.1). Using this test, of 20 patients suspected to be HS/HA but with no confirmatory diagnosis, eight patients were diagnosed as HS. Using logistic regression analysis, the optimum cut-off MFI value between HS and normal controls was 10126. The area under the ROC curve was 0.99. The statistical significance of MFI values was obtained by t -test or Wilcoxon rank sum test as applicable. Compared with normal controls, the MFI values in HS were lower and in megaloblastic anemia were higher which was statistically highly significant (P < 0.01), and the MFI values in CDA were lower which was statistically significant (P < 0.05). False-positive values were obtained in three cases of AIHA and two cases of CDA. The sensitivity and specificity was 96.4% and 94.2% respectively. The EMA-based flow cytometry test is a highly sensitive and specific method for the diagnosis of HS. [source] Thrombotic thrombocytopenic purpura: Results of the patients with thrombotic microangiopathies across Japan by ADAMTS13 analysis during 1998,2008ISBT SCIENCE SERIES: THE INTERNATIONAL JOURNAL OF INTRACELLULAR TRANSPORT, Issue n2 2009Y. Fujimura Background, Thrombotic microangiopathies (TMAs) are pathological conditions, characterized by generalized microvascular occlusion by platelet thrombi, thrombocytopenia, and microangiopathic hemolytic anemia. Two typical phenotypes of TMAs are hemolytic-uremic syndrome (HUS) and thrombotic thrombocytopenic purpura (TTP). Severe deficiency of plasma ADAMTS13 activity (ADAMTS13:AC) is more specific for TTP but not for HUS. Materials & Methods, Since 1998, our laboratory has functioned as a nationwide referral center for TMAs by analyzing ADAMTS13. Of 1564 tested patients from 426 hospitals, 919 were positive for TMAs. Levels of ADAMTS13:AC and the ADAMTS13-neutralizing autoantibodies (ADAMTS13:INH) in these patients were determined by chromogenic act-ELISA and/or by classic von Willebrand factor multimer assay. Results, TMA patients consisted of two groups, those with severe (less than 3% of normal control) and those with non-severe deficiency of ADAMTS13:AC. Additionally, both groups were divided into congenital (n = 65) and acquired (n = 854) TMAs. Of the congenital TMA patients, 41 had ADAMTS13:AC deficiency due to gene mutations, while the remaining 24 had the disease of unknown etiology. The 854 patients with acquired TMAs could be largely grouped into three categories: idiopathic TTP (n = 284), idiopathic HUS (n = 106), and secondary TMAs (n = 464). The secondary TMAs were observed in heterogeneous patient groups and were associated with drugs, connective tissue diseases, malignancies, transplantation, pregnancy, E. coli O157:H7 infection, and other factors. All of the patients with acquired severe ADAMTS13:AC deficiency were positive for ADAMTS13:INH. Conclusion, Although TMAs are highly heterogeneous pathological conditions, one third of TMA patients have severe deficiency of ADAMTS13:AC. Platelet transfusions to such patients are contraindicated. Thus, rapid ADAMTS13:AC assays will be prerequisite in medical facilities where TMA patients are treated. [source] Infection frequently triggers thrombotic microangiopathy in patients with preexisting risk factors: A single-institution experienceJOURNAL OF CLINICAL APHERESIS, Issue 2 2010Kenneth W. Douglas Abstract Thrombotic microangiopathies are rare conditions characterized by microangiopathic hemolytic anemia, microthrombi, and multiorgan insult. The disorders, which include hemolytic uremic syndrome and thrombotic thrombocytopenic purpura, are often acute and life threatening. We report a retrospective analysis of 65 patients presenting to our institution from 1997 to 2008 with all forms of thrombotic microangiopathy. Therapeutic plasma exchange was a requirement for analysis and 65 patients were referred to our institution; 66% of patients were female and median age at presentation was 52 years. Bacterial infection was the most commonly identified etiologic factor and in the multivariate model was the only significant variable associated with survival outcome (odds ratio 5.1, 95% confidence interval, 1.2,21.7). As infection can be considered a common trigger event for thrombotic microangiopathy, patients with hepatobiliary sepsis may benefit from elective cholecystectomy. We conclude that bacterial infection frequently triggers TTP and other thrombotic microangiopathies in patients with preexisting risk factors and propose a model for the development of these syndromes. © J. Clin. Apheresis 2010. © 2010 Wiley-Liss, Inc. [source] Atypical presentations of thrombotic thrombocytopenic purpura: A review,JOURNAL OF CLINICAL APHERESIS, Issue 1 2009Ravi Sarode Abstract Thrombotic thrombocytopenic purpura (TTP) is diagnosed by the presence of microangiopathic hemolytic anemia and thrombocytopenia in a patient who frequently presents with central nervous system involvement and, to a lesser extent, renal dysfunction. Recent understanding of the pathophysiology of TTP due to severe deficiency of von Willebrand factor cleaving protease, known as ADAMTS13, has improved diagnosis of TTP. Once the diagnosis is suspected, life-saving therapeutic plasma exchange therapy is initiated. Occasionally, an unusual clinical presentation makes TTP diagnosis difficult, thus resulting in a delay in the management of TTP. This review highlights a variety of atypical TTP presentations described in the literature. It is intended to bring unusual scenarios to the clinician's awareness, so that timely treatment can be delivered. J. Clin. Apheresis, 2009. © 2008 Wiley-Liss, Inc. [source] Thrombotic thrombocytopenic purpura: 24 years of experience at the American University of Beirut Medical CenterJOURNAL OF CLINICAL APHERESIS, Issue 3 2004Ali Shamseddine Abstract Thrombotic thrombocytopenic purpura (TTP) is a hematological syndrome defined by the presence of thrombocytopenia and microangiopathic hemolytic anemia without a clinically apparent etiology. Patients may also suffer from fever in addition to neurological and renal impairment. Treatment should be initiated as soon as possible, otherwise this rare disease can be fatal. The main treatment options include therapeutic plasma exchange, fresh frozen plasma infusion, and adjuvant agents such as steroids and antiplatelet drugs. A search of patient records was carried out at the American University of Beirut Medical Center looking for patients who developed TTP over a 24-year period extending from 1980 to 2003. Relevant information was collected and analyzed. A total of 47 records were found. All presented with anemia and thrombocytopenia, 83% had neurological symptoms, 61.7% had fever and 34% had renal impairment. All patients were treated with a multimodality regimen including therapeutic plasma exchange, FFP infusion, steroids, antiplatelet agents, vincristine and others. 38 (81%) cases achieved complete remission. Out of these, 12 (31.6%) relapsed and responded to treatment. Patients who did not receive plasma exchange were more likely to relapse (P = 0.032). A second relapse was observed in 6 cases. The overall mortality rate from TTP over 24 years was 21.3%. TTP remains a fatal disease. A high index of suspicion should, therefore, always be present. Treatment options should be further developed and patients should directly be referred to tertiary care centers. J. Clin. Apheresis 19:119,124, 2004. © 2004 Wiley-Liss, Inc. [source] Transient TTP in childhoodPEDIATRIC BLOOD & CANCER, Issue 3 2009Naomi P. Moskowitz MD Abstract Thrombotic thrombocytopenic purpura (TTP) is a type of microangiopathic hemolytic anemia that is uncommon in childhood. Adults with TTP have a high mortality rate unless they are treated with plasma exchange. There are few reports of children with acquired idiopathic TTP, and most of those children received some form of treatment. We describe a child with acquired idiopathic TTP who had severe thrombocytopenia and anemia that resolved over several months without the use of any medications. This case suggests that some children with acquired idiopathic TTP might be safely observed without ill effects. Pediatr Blood Cancer 2009;52:424,426. © 2008 Wiley-Liss, Inc. [source] | ||||||||||