Refractariedad plaquetaria: acercamiento al diagnóstico / Platelet refractoriness: approaches to diagnostic

La refractariedad plaquetaria representa un problema clínico significativo que complica la transfusión de plaquetas, está asociada con resultados clínicos adversos y elevados costos hospitalarios. Se define como una respuesta inadecuada a la transfusión de plaquetas después de dos transfusiones consecutivas. Las causas no inmunes son las más frecuentes y las primeras que deben ser investigadas en el diagnóstico de refractariedad plaquetaria. La refractariedad de causa inmune está mediada por anticuerpos contra antígenos HLA o HPA. Si se identifican los anticuerpos, existen tres formas de identificar unidades de plaquetas compatibles: el tipaje HLA, la prueba cruzada y la predicción de la especificidad del anticuerpo. Se recomienda el empleo de plaquetas fresca ABO idénticas y fenotipadas para eliminar estas variables potenciales como causa de refractariedad(AU)

Platelet refractoriness represent a significant clinical problem that complicates the provision of platelet transfusions, it is associated with adverse clinical outcomes and increases health care costs. Platelet refractoriness is defined as an inadequate response to platelet transfusions after two sequential transfusions. Nonimmune causes are the most likely and the first that should be explored in the diagnosis of platelet refractoriness. Immune-mediated platelet refractoriness is cause by antibodies to human leukocyte antigens (HLAs) and/or human platelet antigens. If antibodies are identified, there are 3 strategies for identifying compatible platelet units: HLA matching, crossmatching, and antibody specificity prediction. It is recommended to use fresh and ABO-matched platelets in the diagnosis of platelet refractoriness to eliminate these potential variables as causes of refractoriness(AU)

Lisado plaquetario y células mononucleares autólogas de la periodontitis crónica. Presentación de un caso / Autologous platelet lysate and mononuclear stem cell of chronic periodontitis. Case presentation

Introducción: El tratamiento de la periodontitis crónica se prolonga por persistencia de la inflamación en tejidos afectados. La medicina regenerativa muestra resultados alentadores. Es la primera vez en Cuba, según bibliografía revisada, que se usa la combinación de lisado plaquetario y células mononucleares autólogas en este tratamiento. Objetivo: Mostrar el efecto de la combinación del lisado plaquetario y células mononucleares autólogas en el tratamiento de la periodontitis. Presentación de un caso: Paciente femenina de 44 años de edad, con diagnóstico de periodontitis, quien desde hace 1 año lleva tratamiento, sin efectuarse procedimientos quirúrgicos por la inflamación persistente. Es remitida a la consulta de periodoncia del Hospital Enrique Cabrera para recibir tratamiento con medicina regenerativa. Se consideró tratar con lisado de plaquetas autólogas, una vez concluido el raspado y alisador radicular, se prefundieron las encías afectadas con el lisado plaquetario. A los 7 días de aplicado el lisado se constatan las encías sin signos clínicos de inflamación, y disminución ostensible del número de dientes afectados y la profundidad o eliminación de las bolsas periodontales y movilidad dentaria. Al mes se trataron quirúrgicamente los defectos óseos con implante de células mononucleares. Al evaluar a los 6 meses, se hallaron de forma variable, signos radiográficos de organización del trabeculado, definición de la cortical y formación ósea en zona de defectos óseos. Conclusiones: El tratamiento combinado del lisado plaquetario autólogo y células mononucleares muestra una evaluación satisfactoria en el tratamiento de la periodontitis crónica y reduce el tiempo de tratamiento(AU)

Introduction: Treatment of chronic periodontitis is prolonged by persistent inflammation in affected tissues. Regenerative medicine shows encouraging results. It is the first time in Cuba, according to the reviewed literature, that the combination of platelet lysate and autologous mononuclear cells is used in this treatment. Objective: to show the effect of the combination of platelet lysate and autologous mononuclear cells in the treatment of periodontitis. Presentation of the case: A 44-year-old female patient diagnosed with periodontitis who had been treated for 1 year without surgical procedures due to persistent inflammation. She is referred to the periodontics consultation of the Dr. Enrique Cabrera General Hospital to receive treatment with regenerative medicine. Treatment with autologous platelet lysate was considered, once the scaling and root planer had been completed, the affected gingivae were prefixed with the platelet lysate. At 7 days after the lysate is applied, the gingiva shows no clinical signs of inflammation, and a noticeable reduction in the number of affected teeth and the depth or elimination of periodontal pockets and tooth mobility. Bone defects with a mononuclear cell implant were surgically treated one month later. When evaluating at 6 months, radiographic signs of trabecular organization, definition of the cortical bone, and bone formation in the area of bone defects were found variably. Conclusions: The combined treatment of autologous platelet lysate and mononuclear cells shows a satisfactory evaluation in the treatment of chronic periodontitis and reduces treatment time(AU)

Aplicación de las plaquetas con fines regenerativos en Cuba / Application of platelets with regenerative purposes in Cuba

Entre los pilares en que se apoya la Medicina Regenerativa están la terapia celular y la administración de factores bioactivos, fundamentalmente los derivados de las plaquetas. En los últimos años, la aplicación de plaquetas con fines regenerativos ha aportado nuevos conocimientos sobre sus posibilidades terapéuticas y se han obtenido avances prometedores con su empleo. En Cuba, el uso de plaquetas en la regeneración de tejidos se está aplicando con resultados favorables en un grupo significativo de enfermedades o condiciones clínicas y endiferentes especialidades, entre las que se encuentran ortopedia y traumatología, angiología, oftalmología, medicina del deporte.Los resultados obtenidos evidencian los beneficios que este tratamiento puede aportar a partir de un proceder simple, seguro, eficiente y económico(AU)

Among the pillars on which Regenerative Medicine is supported are cell therapy and the administration of bioactive factors, mainly those derived from platelets. In recent years, the application of platelets for regenerative purposes has brought new insights into their therapeutic possibilities and promising advances have been made with their use. In Cuba, the use of platelets in tissue regeneration is being applied with favorable results in a significant group of diseases or clinical conditions and different specialties, among which are orthopedics and traumatology, angiology, ophthalmology, sports medicine. The evidences show the benefits that this treatment can provide, from a simple, safe, efficient and economic procedure(AU)

Application of vincristine-loaded platelet therapy in three dogs with refractory immune-mediated thrombocytopenia

Three dogs presented with refractory immune-mediated thrombocytopenia (IMT). All patients failed to respond to prednisone, which is considered a mainstay of immunosuppressive therapy. Vincristine-loaded platelets (VLPs), which act selectively on mononuclear phagocytes,were introduced. After the VLPs were transfused, two dogs responded quickly withimproved clinical signs while the third dogwith recurrent IMT was euthanized due to its deteriorating condition. This case report describesthe efficacy of VLP therapy in refractory IMT patients.

Application of platelet-rich plasma in the treatment of chronic skin ulcer - Case report

The platelet-rich plasma (PRP) has proved promising regarding its applicability in dermatology, especially in the healing of chronic ulcers. The autologous platelet-rich plasma is obtained by centrifuging the blood, so that the components are separated by density gradient. The final product is a gel rich in growth factors that act in tissue repair by activating fibroblasts and inducing extracellular matrix remodeling.

Evolução das técnicas de transplante de fígado: o papel da veia cava inferior / Evolution of liver transplant techniques: the role of the inferior vena cava

O transplante de fígado (TxF) é provavelmente a maior agressão cirúrgica que um paciente pode suportar. Desde a introdução do TxF convencional por Starzl, o qual era baseado na ressecção conjunta do fígado e da veia cava inferior, o procedimento sofreu vários refinamentos. Em termos técnicos, o TxF é o mais complexo entre todos os transplantes de órgãos. Uma combinação dos avanços na técnica cirúrgica e cuidados intensivos vem permitindo um aumento na sobrevida pós-TxF. Uma revisão dos aspectos técnicos do TxF é descrita no presente artigo.

Liver transplantation (LT) is probably the biggest surgical aggression that a patient can endure. Since introduction of the conventional LT by Starzl, which was based on the resection of recipient inferior vena cava (IVC) along the liver, the procedure has undergone several refinements. In terms of technique LT is the most complex of all types of transplantations. A combination of advances in critical case and surgical technique has resulted in a significant improvement in overall patientsurvival after transplantation. Up to date technical aspects of orthotopic liver transplantation are described in the present article.

Plasmodium vivax malaria presenting with severe thrombocytopenia, cerebral complications and hydrocephalus.

Two cases of a one and 4 year old child of plasmodium vivax malaria are reported in association with CNS complications. Both presented with encephalopathy and seizures. One had severe thrombocytopenia, massive intracranial bleed and hydrocephalus requiring shunt surgery while the other had gastrointestinal manifestations, encephalopathy and hydrocephalus. Both responded to quinine but are left with sequelae.

Antiplatelet antibodies in cases of Glanzmann's thrombasthenia with and without a history of multiple platelet transfusion.

Antiplatelet antibodies are known to be present in a wide spectrum of patients, which include chronic Idiopathic Thrombocytopenic Purpura (ITP), infections, etc., including Glanzmann's thrombasthenia (GT) patients who receive multiple platelet transfusions. The presence of natural antibodies to platelet receptors is not studied in cases of GT. We studied the antiplatelet antibodies in 23 patients with GT, 15 of which had received multiple transfusions and eight that had not received transfusions, along with 50 cases of chronic ITP. The prevalence and specificity of platelet-bound antibodies were detected by inhibition assays using O-group platelets on flow cytometry. The mean antiplatelet antibodies in 15 patients of GT who had not received transfusions and eight patients with multiple transfusions was 8427 + 2131.88 and 9038 + 2856 antibodies/platelet, respectively, while in case of the 50 ITP patients studied, it was 22166 + 5616 antibodies/platelet (Normal Range 1500–3200 antibodies/platelet). We conclude that GT patients who have not received transfusions may develop antiplatelet antibodies to the missing/abnormal receptor. Whether this is due to a molecular mimicry or due to some other mechanism needs to be explored.

An Evaluation of Platelet Transfusion Response Using HLA Crossmatch-compatible Donors in Patients with Platelet Refractoriness / 대한진단검사의학회지

BACKGROUND: Majority of immune-mediated platelet refractoriness is caused by HLA alloimmunization and can be effectively managed by HLA-matched platelet transfusions. However, HLA class I-typed large-sized donor registry has not been well established in Korea. We evaluated the effectiveness of platelet transfusion using HLA crossmatch-compatible donors without HLA typing. METHODS: Sixteen patients showing platelet refractoriness to random donor platelets (1 hr corrected count increment [CCI] 60%) were crossmatched with 78 platelet apheresis-eligible donors using National Institute of Health (NIH) and anti-human globulin (AHG) lymphocytotoxicity methods. NIH negative/AHG negative and NIH negative/AHG positive donors were selected as best and second choice donors, respectively. RESULTS: Eleven patients (11/16, 69%) could find NIH-crossmatch negative donors and 27 donors (27/78, 35%) belonged to the best donors. To 8 patients, 32 apheresis platelet products from 19 donors were transfused. The mean 1 hr and 24 hr CCI values from the best donors were significantly higher than those from random donors (17,893 vs 2,358, P=0.003; 8,292 vs -614, P<0.001), whereas such differences were not observed for those from the second choice donors. Platelet storage time was inversely correlated with CCI values and platelets stored < or =10 hr after collection gave significantly higher CCI values. Neither ABO match nor donor status (related vs unrelated) affected the transfusion effectiveness. CONCLUSIONS: Effective post-transfusion platelet increment using HLA crossmatch-compatible donors was attained in patients with platelet refractoriness due to HLA antibodies, and this method can be used effectively where HLA-typed platelet donor registry is not available.

Component therapy.

The dramatic advances that have taken place in recent years in the care of sick and premature infants also have been matched by a similar increase in the use of blood transfusion therapy. Haematological features indicate that a newborn has a blood volume of 85-125 ml/kg the foetal haemoglobin is 60-85% and average Hb in full term infant is 18 gm/dl. By 2-3 months it falls to 11-12 g/dl the main cause of anemia are iron poor diet, weaning diets recurrent or chronic infections and hemolytic episodes in malarious areas. The red cells transfusions are usually top up transfusions, exchange transfusions, partial exchange transfusions. Top up- are for investigational losses and correction of mild degrees of anemias, upto to 5-15 ml/kg. They comprise 90% of all neonatal transfusions and are used in low birth babies in special care units for a maximum of 9-10 episodes. The walk in donor programs once popular are not much in vogue. The threshold for transfusion is 8-10 g/dl Hb for upto 5 weeks. Exchange transfusions are done for correction of anemia, removal of bilirubin, removal of antibodies and replacement of red cells. Ideally plasma reduced red cells that are not older than 5 days are used. It is prepared by removal of 120 ml of standard whole blood donation. The advantage of fresh cells is that hyperkalemia is avoided and good post transfusion survival acceptable red cell oxygen affinity. However it has to be screened for sickle cell disease and G6PD deficiency. Indications for exchange transfusion are kernicterus, neonatal hemolysis, G6PD deficiency, ARDS, neonatal sepsis, DIC and neonatal isoimmune thrombocytopaenia. Complications include over transfusion, perforation of major vessels, hypocalcaemia, citrate toxicity, hypothermia, hypoglycaemia, thrombocytopenia, necrotizing enterocolitis, GVHD, bacterial, viral infections. Partial exchange transfusions are done for symptomatic anemia, where Hb<10 g/dl, it is indicated in polycythemia and hyperviscosity syndromes. Exchange volume = Blood volume x (observed Hct-Desired HCt) divided observed Hct. Points to consider-there is weak expression of ABO antigens so particular care while grouping. Transfusing volumes should be 2-5 ml/kg/hour in paediatric bags of 50-100 ml with infusion devices. Platelet transfusion are indicated in neonatal throbocytopaenia, thrombocytopaenia due to sepsis, DIC, bacterial pathogens, CMV, TORCHS, Obstetric conditions such as pre eclampsia, intrauterine death abruption placenta birth injury hypoxia schock neonatal iso immune thrombocytopaenia and maternal ITP. Administration 1 RDE/pack per 2.5 kg single dose of fresh platelets less than 24hrs which contains 55 x 10(9) cells. This also contributes fresh plasma so is useful for coagulation defects also, though there is a risk of CMV and GVHD due to leucocyte contamination. Granulocyte concentrate; Gravity leucopheresis-1:8 ratio of 60 ml of 6% HES made to stand for 1hr.

Platelet transfusion practice during dengue fever epidemic.

Blood components especially platelet concentrates due to their short shelf life are frequently in limited supply. Appropriate use of blood components is required to ensure their availability for needy patients as well as to avoid the unnecessary risk of transfusion-transmitted diseases. Medical audit of blood transfusion practice, which forms an important part of quality assurance programme in a transfusion centre, can provide grounds for improvement in transfusion medicine practice. During the epidemic of dengue fever in Oct., 1996, 1837 patients were admitted as dengue haemorrhagic fever in a teaching hospital in Delhi. Two hundred and eight patients (11.3%) were given platelet transfusions. Retrospective analysis of these platelet transfusions was done. It was observed that in only 52 (25%) out of 208 patients the information on platelet counts was provided. History of active bleeding was obtained only in 65 (31.2%) patients. About 35% patients received unnecessary prophylactic transfusions and during 89% of the transfusion episodes inappropriate dose of platelet concentrate was given. Information regarding post-transfusion recovery could be obtained in only 16.5% of transfusion episodes. The study emphasises the need for development of specific guidelines for transfusion of blood components, constant interaction and co-ordination amongst clinicians and transfusion centre for implementation of these guidelines, and a regular medical audit to review the optimal utilisation of blood components.

Terapia transfusional: indicaciones de componentes sanguíneos / Transfusion therapy: indicators of blood components

We know that no set of rules can be written to apply to the constellation of variables that will be present when a physician is confronted with a decision to transfuse a patient. Therefore, the intent of this guidelines is to provide assistance to clinicians who need to prescribe a blood component transfusion. We do not know precisely when a transfusion should be given because we do not know the mitocondrial oxigen requeriments for any organ or tissue of for the patient as a whole. For that reason, we use surrogate measurements to guide us. Hopefully, this article offers practical suggestions and will be useful for clinicians who prescribe blood component therapy