Púrpura trombocitopénica idiopática en el embarazo: a propósito de un caso

Idiopathic purple thrombocytopenia is a hemorrhagic pathology, characterized by a decrease in the platelet count during pregnancy, mediated by cells and anti-platelet antibodies, causing the premature destruction of platelets by the reticuloendothelial system, which during pregnancy could lead to a commitment to maternal fetal wellbeing in severe stages. This pathology occurs in 1 out of every 1,000 to 10,000 pregnancies, and corresponds to 3% of thrombocytopenic pregnancies. The goal of management is to maintain platelet counts within safe ranges, recommending starting harmacological management when a platelet count lower than 10,000 / uL is found at any time during pregnancy or 30,000 / uL in the second or third trimester. The case presented corresponds to a 40-yearold woman in the first trimester of pregnancy with a history of chronic idiopathic purple thrombocytopenic, with severe thrombocytopenia at the time of admission to the Hospital. Keywords: Idiopathic thrombocytopenic purpura. Pregnancy. Blood platlets.

Point-of-care microvolume cytometer measures platelet counts with high accuracy from capillary blood

Background Point-of-care (PoC) testing of platelet count (PLT) provides real-time data for rapid decision making. The goal of this study is to evaluate the accuracy and precision of platelet counting using a new microvolume (8 μL), absolute counting, 1.5 kg cytometry-based blood analyzer, the rHEALTH ONE (rHEALTH) in comparison with the International Society of Laboratory Hematology (ISLH) platelet method, which uses a cytometer and an impedance analyzer. Methods Inclusion eligibility were healthy adults (M/F) ages 18–80 for donation of fingerprick and venous blood samples. Samples were from a random N = 31 volunteers from a single U.S. site. Samples were serially diluted to test thrombocytopenic ranges. Interfering substances and conditions were tested, including RBC fragments, platelet fragments, cholesterol, triglycerides, lipids, anti-platelet antibodies, and temperature. Results The concordance between the rHEALTH and ISLH methods had a slope = 1.030 and R2 = 0.9684. The rHEALTH method showed a correlation between capillary and venous blood samples (slope = 0.9514 and R2 = 0.9684). Certain interferents changed platelet recovery: RBC fragments and anti-platelet antibodies with the ISLH method; platelet fragments and anti-platelet antibodies on the rHEALTH; and RBC fragments, platelets fragments, triglycerides and LDL on the clinical impedance analyzer. The rHEALTH’s precision ranged from 3.1–8.0%, and the ISLH from 1.0–10.5%. Conclusions The rHEALTH method provides similar results with the reference method and good correlation between adult capillary and venous blood samples. This demonstrates the ability of the rHEALTH to provide point-of-care assessment of normal and thrombocytopenic platelet counts from fingerprick blood with high precision and limited interferences.

Post-transfusion purpura due to anti HPA–1a antibodies – a retrospective case report

Post-transfusion purpura is a life-threatening adverse reaction associated with a reduction in platelet counts below 10 x 109/L and bleeding. It usually occurs in women who, due to their pregnancies, have developed antibodies directed against human platelet antigen (HPA), most often anti-HPA 1a. The case described by us concerned an 83-year-old woman who received two units of red blood cells (RBC) due to severe secondary anemia. Seven days after the transfusion, she developed skin symptoms of thrombocytopenic diathesis, gastrointestinal bleeding, and a reduced number of platelets (3 x 109/L), and the patient’s serum (genotype HPA-1b/1b) was positive for anti-platelet antibodies with HPA-1a specificity and directed against human leukocyte antigen (HLA) class I and class II antibodies, unresponsive to the lymphocytotoxic test. Prompt diagnosis by our transfusion medicine consultant and the initiation of treatment with intravenous immunoglobulins certainly shortened the duration of thrombocytopenia and bleeding, and possibly also saved the patient’s life.

Multicoagulant resistant pseudothrombocytopenia

Pseudo thrombocytopenia is the estimation of low platelet counts by a Hematology analyzer in spite of lack of shortage in platelets. EDTA-induced pseudo thrombocytopenia, commonly seen in clinical practice, occurs mainly due to anti platelet antibodies. Pseudo thrombocytopenia is seen in normal healthy individuals as well as in other disorders like cardiovascular, liver, autoimmune diseases and malignancy. We are presenting a case of multi coagulant resistant dependent thrombocytopenia. The purpose of the case report is to review approaches to pseudo thrombocytopenia. The case has coagulant resistant dependent thrombocytopenia in association with Anasarca and was a known case of cardiomyopathy with severely dilated left atrium, left ventricle &right atrium. Keywords: Pseudo platelet aggregation, multicoagulant resistant thrombocytopenia, pseudo thrombocytopenia. Continuous...

Detection of anti-platelet antibodies by flow cytometry in patients with immunological thrombocytopenic purpura

En raison de la non disponibilité d’un test biologique qui confirme le diagnostic du PTI « « purpura thrombopénique immunologique », ce dernier se pose par élimination de toutes les autres causes secondaires d’une thrombopénie. La cytomètrie en flux utilisant la fluorescence, a permis la détection des immunoglobulines associées aux membranes plaquettaires appelées PAIG (Platelet associated immunoglobulin). La recherche des PAIG représente une technique très prometteuse qui peut être appliquée pour le dépistage du PTI selon les nombreuses études réalisées dans ce sujet. D’autres versions modifiées de la recherche des PAIG ont permis une quantification des PAIG, en utilisant une calibration à base de microbilles fluorescentes ou des plaquettes témoins positives sensibilisées par des Ig de surface. L’utilisation des microbilles dans les études récentes a permis l’identification des glycoprotéines plaquettaires, cibles des autoanticorps, la technique est appelée FCIA (flow cytometry immunobead assay). Le but de cette revue de littérature est de rapporter les principes et les résultats de ces techniques. Mots Clés : Purpura Thrombopénique Immunologique ; cyrtométrie en flux ; anticorps.