Peck-Radosavljevic Markus
Department of Gastroenterology, Hepatology, Endocrinology and Nephrology, Klinikum Klagenfurt am Wörthersee, Klagenfurt, Austria.
Liver Int. 2017 Jun;37(6):778-793. doi: 10.1111/liv.13317. Epub 2016 Dec 27.
Thrombocytopenia is a common haematological disorder in patients with chronic liver disease. It is multifactorial and severity of liver disease is the most influential factor. As a result of the increased risk of bleeding, thrombocytopenia may impact upon medical procedures, such as surgery or liver biopsy. The pathophysiology of thrombocytopenia in chronic liver disease has long been associated with the hypothesis of hypersplenism, where portal hypertension causes pooling and sequestration of all corpuscular elements of the blood, predominantly thrombocytes, in the enlarged and congested spleen. Other mechanisms of importance include bone marrow suppression by toxic substances, such as alcohol or viral infection, and immunological removal of platelets from the circulation. However, insufficient platelet recovery after relief of portal hypertension by shunt procedures or minor and transient recovery after splenic artery embolization have caused many to question the importance and relative contribution of this mechanism to thrombocytopenia. The discovery of the cytokine thrombopoietin has led to the elucidation of a central mechanism. Thrombopoietin is predominantly produced by the liver and is reduced when liver cell mass is severely damaged. This leads to reduced thrombopoiesis in the bone marrow and consequently to thrombocytopenia in the peripheral blood of patients with advanced-stage liver disease. Restoration of adequate thrombopoietin production post-liver transplantation leads to prompt restoration of platelet production. A number of new treatments that substitute thrombopoietin activity are available or in development.
血小板减少症是慢性肝病患者常见的血液系统疾病。它是多因素导致的，其中肝病的严重程度是最具影响力的因素。由于出血风险增加，血小板减少症可能会影响诸如手术或肝活检等医疗程序。慢性肝病中血小板减少症的病理生理学长期以来一直与脾功能亢进假说相关，即门静脉高压导致血液中所有血细胞成分（主要是血小板）在肿大和充血的脾脏中积聚和滞留。其他重要机制包括酒精或病毒感染等有毒物质对骨髓的抑制，以及从循环中免疫清除血小板。然而，分流手术缓解门静脉高压后血小板恢复不足，或脾动脉栓塞后血小板仅有轻微和短暂的恢复，这使得许多人质疑该机制对血小板减少症的重要性及相对贡献。细胞因子血小板生成素的发现揭示了一个核心机制。血小板生成素主要由肝脏产生，当肝细胞大量受损时其水平会降低。这导致骨髓中血小板生成减少，进而导致晚期肝病患者外周血血小板减少。肝移植后恢复足够的血小板生成素产生会促使血小板生成迅速恢复。一些替代血小板生成素活性的新疗法已经可用或正在研发中。
