危重
患者
血小板
减少
诊治
危重患者血小板减少的诊治,四川省肿瘤医院ICU刘真君2022.4,第一页,共五十二页。,概述血小板减少的定义、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,2022 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,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、根底疾病心、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。,相关病史根底疾病、药物史、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,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/活检,了解巨核细胞系巨核细胞数量及产板情况,还可发现粒系/红系异常,第十二页,共五十二页。,破坏增多骨髓检查巨核细胞数量正常或增加。局部 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%混悬液参加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,说明红细胞外表有抗体或补体。Coombs间接试验:先将受试的血清参加等量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,第十五页,共五十二页。,血小板减少诊断简易流程,第十六页,共五十二页。,以下的实验室方法能帮助我们进一步明确诊断,第十七页,共五十二页。,平均血小板容积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,2022 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),2022 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.2022;119(3):173-7.,第二十一页,共五十二页。,未成熟血小板比例和网织血小板比例 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%(9.89-22.40%).(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.2022 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,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,更多的是根底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).2022 Oct;42(4):142-52.Thrombocytopenia in the intensive care unit patient.Hematology Am Soc Hematol Educ Program.2022;2022:135-43.,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 activation and consumption.The fall in platelet count associated with sepsis is typically gradual,occurring over 5 to 7 days,and the thrombocytopenia is characteristical