de Oliveira Souza Evandro, D'Amico Élbio Antônio, Flores da Rocha Tânia Rúbia, Marcondes Ferreira Caroline, Medeiros Batista Juliana, Carneiro D'Albuquerque Luiz Augusto, Carrilho Flair José, Queiroz Farias Alberto
Division of Gastroenterology and Hepatology, University of Sao Paulo School of Medicine, Av. Dr. Eneas Carvalho de Aguiar, 255, 9th floor, office 9159, Sao Paulo, SP 05403-000, Brazil.
Hemostasis Laboratory, Hematology Service, University of Sao Paulo School of Medicine, Av. Dr. Eneas Carvalho de Aguiar, 255, 2nd floor, Sao Paulo, SP 05403-000, Brazil.
Hepatobiliary Pancreat Dis Int. 2020 Dec;19(6):555-560. doi: 10.1016/j.hbpd.2019.12.009. Epub 2020 Jan 11.
Thrombocytopenia is a possible risk factor for bleeding after band ligation of esophageal varices. However, elevated von Willebrand factor (VWF) in cirrhosis improves platelet function and could decrease this risk. Our objective was to assess platelet function in patients with cirrhosis undergoing esophageal variceal ligation (EVL).
The assessment consisted of platelet count, antigen and activity of VWF and VWF-cleaving protease ADAMTS-13 activity, and a platelet adhesion and aggregation test simulating vascular flow in vivo (Impact-R) prior to EVL.
Totally 111 patients were divided into three groups according to platelet count: (1) < 50 × 10/L (n = 38, 34.2%); (2) 50 × 10/L to 100 × 10/L (n = 47, 42.3%); and (3) > 100 × 10/L (n = 26, 23.4%). No statistically significant difference was found in the aggregate size of platelets [group 1: 41.0 (31.8-67.3) µm; group 2: 47.0 (33.8-71.3) µm; and group 3: 47.0 (34.0-66.0) µm; P = 0.60] and no significant correlation was found between aggregate size and platelet count (Spearman r = 0.07; P = 0.47). Surface coverage was 4.1% (2.8%-6.7%), 8.5% (4.0%-10.0%), and 9.0% (7.1%-12.0%) (P < 0.001) in groups 1, 2 and 3, respectively and correlated with platelet count (Spearman r = 0.39; P < 0.0001). There was no significant difference between groups in VWF or ADAMTS-13. Post-EVL bleeding occurred in six (5.4%) patients (n = 2 in group 1, n = 1 in group 2, and n = 3 in group 3; P = 0.32). Patients with bleeding had higher MELD scores [15.0 (11.3-20.3) versus 12.0 (10.0-15.0); P = 0.025], but no difference was demonstrated for platelet function parameters.
Platelet function is preserved even in the presence of thrombocytopenia, including in the patients with post-EVL bleeding.
血小板减少是食管静脉曲张套扎术后出血的一个潜在风险因素。然而，肝硬化患者血管性血友病因子（VWF）水平升高可改善血小板功能，并可能降低这一风险。我们的目的是评估接受食管静脉曲张套扎术（EVL）的肝硬化患者的血小板功能。
评估内容包括血小板计数、VWF抗原和活性、VWF裂解蛋白酶ADAMTS-13活性，以及EVL术前模拟体内血流的血小板黏附和聚集试验（Impact-R）。
根据血小板计数，111例患者共分为三组：（1）<50×10⁹/L（n = 38，34.2%）；（2）50×10⁹/L至100×10⁹/L（n = 47，42.3%）；（3）>100×10⁹/L（n = 26，23.4%）。血小板聚集大小在三组间无统计学显著差异[第1组：41.0（31.8 - 67.3）µm；第2组：47.0（33.8 - 71.3）µm；第3组：47.0（34.0 - 66.0）µm；P = 0.60]，且聚集大小与血小板计数之间无显著相关性（Spearman秩相关系数r = 0.07；P = 0.47）。第1、2、3组的表面覆盖率分别为4.1%（2.8% - 6.7%）、8.5%（4.0% - 10.0%）和9.0%（7.1% - 12.0%）（P < 0.001），且与血小板计数相关（Spearman秩相关系数r = 0.39；P < 0.0001）。三组间VWF或ADAMTS-13无显著差异。EVL术后有6例（5.4%）患者发生出血（第1组2例，第2组1例，第3组3例；P = 0.32）。出血患者的终末期肝病模型（MELD）评分更高[15.0（11.3 - 20.3）比12.0（10.0 - 15.0）；P = 0.025]，但血小板功能参数无差异。
即使存在血小板减少，包括EVL术后出血的患者，血小板功能仍得以保留。
