Course Of Thrombocytopenia Research Articles

Clinical correlates and course of thrombocytopenia during percutaneous coronary intervention in the era of abciximab platelet glycoprotein IIb/IIIa blockade

Background Thrombocytopenia is infrequently associated with abciximab therapy but may contribute to hemorrhagic risk. Factors associated with development of thrombocytopenia, the role of weight-adjustment in concomitant heparin administration, and clinical outcomes in patients with thrombocytopenia are not well defined. Methods and Results Pooled data from 3 placebo-controlled, randomized trials (EPIC, EPILOG, and EPISTENT) of abciximab therapy during percutaneous coronary intervention identified 178 patients (2.4% of 7290 patients) in whom thrombocytopenia (platelet count <100 × 109/L) developed after enrollment. Multivariate regression analysis identified age (>65 years; P <.001), weight (<90 kg; P =.023), baseline platelet count (<200 × 109/L; P <.001), abciximab therapy (P =.002), and enrollment into the EPIC trial (P <.001) to be associated with development of thrombocytopenia. Major and minor nonsurgical hemorrhage and transfusion were more frequent (all P <.001) in thrombocytopenic patients. Although the primary composite clinical end point of these trials (death, myocardial infarction, or urgent revascularization to 30 days) was observed with similar frequency in patients with (11.2%) and those without (7.9%; P =.114) thrombocytopenia, 30-day mortality rate was higher in thrombocytopenic patients (8.4% vs 0.6%, respectively; P <.001). This excess mortality rate persisted after excluding patients in whom thrombocytopenia was first noted after the performance of coronary bypass surgery (4.8% vs 0.6%; P <.001). Among patients in whom thrombocytopenia developed during these trials, those who received prophylactic abciximab had fewer primary end point events (7.1% vs 23.1%; P =.056) and had a lower 30-day mortality rate (3.5% vs 15.4%; P =.048) than patients with thrombocytopenia who had received prophylactic placebo. Conclusions Thrombocytopenia associated with abciximab therapy for percutaneous coronary intervention was more frequent in older, lighter-weight patients, those with lower baseline platelet counts, and in those patients who were enrolled into the EPIC trial. Both bleeding and transfusion events occur more frequently in patients with thrombocytopenia. Patients in whom thrombocytopenia developed during these trials had increased mortality rates to 30 days not attributable to the performance of coronary bypass surgery. Among patients with thrombocytopenia, those who received prophylactic abciximab had better clinical outcomes including survival than those who did not. (Am Heart J 2000;140:74-80.)

Drug-induced thrombocytopenia: clinical data on 309 cases and the effect of corticosteroid therapy.

To analyse the clinical picture and the course of thrombocytopenia induced by non-cytotoxic drugs, and to evaluate a possible therapeutic effect of corticosteroids. A retrospective analysis of 309 well-documented cases of drug-induced thrombocytopenia was performed. Data sources were reports from the files of the Danish Committee on Adverse Drug Reactions and discharge summaries. The median length of exposure to the offending drug, before development of thrombocytopenia, was 21 days. The median nadir platelet count was 11 x 10(9).l-1, and 74% of the patients had clinical haemorrhage. Bone marrow examination generally showed hyperplastic reactive changes and a variable number of megakaryocytes. Slight leucopenia was present in 6% of the patients and 16% were anaemic. Complete recovery was seen in 87% of cases, with a median recovery rate of 8 days. The standard treatment was corticosteroids, which were administered in 53% of the cases. No difference in recovery between corticosteroid-treated and untreated patients was observed. No other clinical parameter affected the recovery rate. The mortality rate due to haemorrhage was 3.6%. Thrombocytopenia induced by non-cytotoxic drugs is characterised by heterogeneous clinical picture and recovery is generally rapid. Although corticosteroids seem inefficient, we still recommend that severe symptomatic cases of drug-induced thrombocytopenia are treated as idiopathic thrombocytopenic purpura due to the difficult initial differentiation between the two conditions.

Course of thrombocytopenia of chronic liver disease after transjugular intrahepatic portosystemic shunts (TIPS). A retrospective analysis.

Thrombocytopenia associated with chronic liver disease presents a difficult management issue. Most reports conclude that portocaval and distal splenorenal shunts do not improve platelet counts in this setting. The response of thrombocytopenia after transjugular intrahepatic portosystemic shunt placement has not been studied. All platelet counts of 21 patients undergoing intrahepatic shunt placement were determined retrospectively to accumulate values at one month prior to procedure, weekly for the first month after the procedure, and monthly thereafter to six months. Comparison of pre- and postshunt platelet means showed a significant increase in counts in patients with a postshunt portal pressure gradient < 12 mm Hg, with the increment evident by one week after the procedure. This response was not seen when preshunt thrombocytopenia was used as the lone variable. This study suggests that the transjugular intrahepatic portosystemic shunt may improve the thrombocytopenia associated with liver cirrhosis when these pressure gradients are attained.

Characterization of autoantibodies against the platelet glycoprotein antigens IIb/IIIa in childhood idiopathic thrombocytopenia purpura.

The majority of children with idiopathic thrombocytopenia (ITP) have an acute self-limiting course and no diagnostic test has been identified which will predict the course of thrombocytopenia and detect those with the chronic autoimmune form. The detection of autoantibodies directed against the platelet glycoprotein complex IIB/IIIa, may identify patients with chronic ITP. Serum anti-GP IIb/IIIa antibodies were assessed by the indirect MAIPA assay in 54 children with immune thrompocytopenia at initial presentation along with an additional 7 children previously diagnosed with chronic ITP, to determine if there was a difference in antibody positivity between acute and chronic ITP patients, and whether the identification of antibodies could be used as a predictive test at diagnosis. There was no significant difference in the percentage of antibodies detected in children classified with acute ITP (27/40-68%) compared to children with chronic ITP (13/21-62%, P > 0.05). Patients with acute ITP had significantly lower mean platelet counts at diagnosis compared to the chronic ITP group (16,225/mm3 vs 32,250/mm3, P < 0.05), though there was no significant difference in the bleeding manifestations between the acute and chronic ITP groups. Serum anti-GP IIb/IIIa antibodies are detected in a high percentage of children with ITP and autoantibodies appear to be involved in the pathogenesis of both acute and chronic ITP. The detection of anti-GP IIb/IIIa antibodies at diagnosis, however, does not appear to be a useful prognostic test in childhood ITP.