2022年医学专题—危重患者血小板减少的诊治(1).pptx

危重患者血小板减少(jinsho)的诊治,四川省肿瘤医院ICU刘真君2017.4,第一页，共五十二页。,概述血小板减少(jinsho)的定义、机制、诊断思路、常用的检查方法危重患者中血小板减少的诊断和治疗总结病例讨论,第二页，共五十二页。,血小板减少（thrombocytopenia）定义为各种遗传或获得性因素导致的血小板减少，血小板计数150.0 x 10(9)/L，通常(tngchng)小于100.0 x 10(9)/L.其主要机制为破坏增加（hyperdestructive）、生成减少（hypoproductive）和分布异常（altered distribution,常见于充血性脾大或低体温）。,第三页，共五十二页。,Hospital-acquired thrombocytopenia.Hosp Pract,2014 Oct;42(4):142-52.,第四页，共五十二页。,第五页，共五十二页。,第六页，共五十二页。,血小板减少的病因多样(du yn)，涉及多个学科，常规检查特异性和敏感性不高，特异性检查受到技术条件和标准化的制约难以开展，导致诊断及鉴别诊断困难。同一病因导致血小板减少的时间、程度个体差异大，发生严重出血受到患者年龄、基础疾病（心、肝、肾等）和有创操作等的影响，及时评估、干预非常重要。,第七页，共五十二页。,相关病史（基础疾病、药物(yow)史、出血事件）查体（出血倾向、肝脾淋巴结、免疫相关疾病、皮肤巩膜黄染）,第八页，共五十二页。,外周血涂片(t pin),EDTA抗凝剂导致的血 小板聚集（clumping），自动血细胞计数仪中血小板计数下降，称为(chn wi)假性血小板减少（pseudothrombocytopenia）人工计数或枸橼酸抗凝可以识别,第九页，共五十二页。,裂红细胞（破碎(p su)红细胞）,第十页，共五十二页。,球形红细胞,第十一页，共五十二页。,骨髓涂片(t pin)/活检,了解巨核细胞系（巨核细胞数量(shling)及产板情况），还可发现粒系/红系异常,第十二页，共五十二页。,破坏增多骨髓(su)检查巨核细胞数量正常或增加。部分 ITP可见巨核细胞成熟障碍，产板少。,第十三页，共五十二页。,生成减少骨髓涂片巨核细胞减少。再障患者活检增生极度低下，造血(zo xu)组织少。,第十四页，共五十二页。,即Coombs直接试验:将洗涤过的红细胞2%混悬液加入Coombs试剂，混和后离心一分钟促进凝集。如果肉眼或显微镜下能见到红细胞凝集，即为阳性(yngxng)，说明红细胞表面有抗体或补体。Coombs间接试验:先将受试的血清加入等量5%适当的正常红细胞(Rh阳性的O型红细胞)，在37温育3060分钟，以促使血清中的半抗体结合于红细胞上(致敏)，将红细胞充分洗涤，以后同直接试验。,抗人球蛋白试验(shyn),第十五页，共五十二页。,血小板减少诊断(zhndun)简易流程,第十六页，共五十二页。,以下的实验室方法(fngf)能帮助我们进一步明确诊断,第十七页，共五十二页。,平均(pngjn)血小板容积（MPV，meanplateletvolume）One hundred two patients were completely evaluated.When compared with the BM examination,the MPV of 7.9 fl could predict hyperdestructive sensitivity of 82.3%(95%CI:70.5-90.8),specificity of 92.5%(95%CI:79.6-98.4),positive predictive value of 94.4%(95%CI:84.6-98.8),negative predictive value of 77.1%(95%CI:62.7-88.0)A prospective evaluation of normal mean platelet volume in discriminating hyperdestructive thrombocytopenia from hypoproductive 0thrombocytopenia.International journal of laboratory hematology,2008 Oct;30(5):408-14.,第十八页，共五十二页。,血小板指数（platelet indices），包括MPV,血小板体积变异(biny)宽度（platelet size deviation width，PDW)和大血小板比率（platelet-to-large-cell ratio，P-LCR)The study group was divided into two categories:hypoproliferative and destructive thrombocytopenia All the threeplateletindiceswere significantly higher in destructive group as compared to the hypoproliferative category,第十九页，共五十二页。,134 thrombocytopenic patients(69 men,65 women)who were divided into two groups group I(n=63)included ITP patients group II(n=71)included patients with HT due to myelosuppression secondary to chemotherapy Concerning MPV and PDW indices,sensitivity,specificity,positive prognostic value,negative prognostic value,efficiency and Youden index were 100%for thediagnosisof ITP.On the contrary,the values for P-LCR were significantly lower。,第二十页，共五十二页。,血小板指数的局限性在于血小板严重(ynzhng)下降的患者（10 x 10(9)/L）结果有较大的偏差，输血等治疗措施影响对结果的判断。在ICU的应用价值需要再评估。Role of platelet volume indices in the differential diagnosis of thrombocytopenia:a simple and inexpensive method.Hematology(Amsterdam,Netherlands),2009 Jun;14(3):182-6.Increased values of mean platelet volume and platelet size deviation width may provide a safe positive diagnosis of idiopathic thrombocytopenic purpura.Acta Haematol.2008;119(3):173-7.,第二十一页，共五十二页。,未成熟血小板比例(bl)和网织血小板比例(bl)Group 1.CentralthrombocytopeniaIPF 8.67%(6.49-10.46%)RP 4.08%(2.86-5.30%)Group 2.Thrombocytopenia as a result of enhanced peripheralplateletdestruction6.80%(12.20-21.39%)，16.14%).(P 0.01).Group 3.Peripheral non-immune thrombocytopenia by abnormaldistribution9.04%(6.95-11.14%)，5.23%(3.41-7.05%).Correlation between immature platelet fraction and reticulated platelets.Usefulness in the etiology diagnosis of thrombocytopenia.Eur J Haematol.2010 Aug;85(2):158-63.,第二十二页，共五十二页。,促血小板生成素（Thrombopoietin，TPO)在生成障碍患者，特别是再障患者明显升高，但在鉴别诊断中的价值有限。血小板相关抗体在免疫性血小板减少中有一定的价值，但检测方法的标准化和特异性需要(xyo)再评估。Is the thrombopoietin assay useful for differential diagnosis of thrombocytopenia?Analysis of a cohort of 160 patients with thrombocytopenia and defined platelet life span.Clin Chem.2001 Sep;47(9):1660-5.Attempt to improve the diagnosis of immune thrombocytopenia by combined use of two different platelet autoantibodies assays(PAIgG and MACE).Haematologica.2002 Oct;87(10):1046-52.Quantification of platelet-associated IgG for differential diagnosis of patients with thrombocytopenia.Thromb Haemost.2000Nov;84(5):779-83.,第二十三页，共五十二页。,以上是简易流程(lichng)，最常见的几种疾病。针对住院特别是ICU患者情况可能更复杂，更多的是基础疾病和治疗性因素导致的血小板减少，医院获得性血小板减少（Hospital-acquired thrombocytopenia）。Hospital-acquired thrombocytopenia.Hosp Pract(1995).2014 Oct;42(4):142-52.Thrombocytopenia in the intensive care unit patient.Hematology Am Soc Hematol Educ Program.2010;2010:135-43.,第二十四页，共五十二页。,Infection is a common cause of thrombocytopenia.Viral infections associated with thrombocytopenia include the human immunodeficiency virus,hepatitis C virus,and Epstein-Barr virus，cytomegalovirus Thrombocytopenia is also frequent in patients with bacterial infections and sepsis or severe sepsis.Mechanisms of infection-induced thrombocytopenia are multiple and may include bone marrow suppression,peripheral immune destruction,and ac