Manoharan A, Brighton T, Gemmell R, Lopez K, Moran S, Kyle P
Department of Clinical Haematology, St. George Hospital, University of New South Wales, Kogarah, Sydney, Australia.
Int J Hematol. 2002 Oct;76(3):272-8. doi: 10.1007/BF02982798.
Forty-eight patients with myelodysplastic syndromes and a platelet count greater than 80 x 10(9)/L were the subjects of a study of platelet function. A whole-blood platelet lumi-aggregometer was used for simultaneous measurement of platelet aggregation by the impedance method and of adenosine triphosphate-dense granule release. The results were correlated with skin bleeding time and episodes of clinical bleeding or thrombosis. Thirty-five patients had at least 1 abnormal result indicating platelet hypoactivity; 7 patients had mixed platelet hypoactivity and hyperactivity; and 4 patients had platelet hyperactivity. Only 2 patients had normal results. There was good correlation between platelet hypoactivity and prolonged skin bleeding time (P = .005); however, several patients with platelet hypoactivity had normal skin bleeding times. This finding suggested that whole-blood platelet aggregation studies may be more sensitive than bleeding time in identification of patients at risk of bleeding. Clinical hemorrhage was frequent (32 patients) in this cohort despite platelet counts greater than 100 x 10(9)/L. This finding indicated platelet hypofunction was clinically important. In contrast, only 2 of the 13 patients with thrombotic events had evidence of platelet hyperactivity, suggesting that other clinical factors are probably more important determinants of thrombosis. These observations confirm that platelet dysfunction is common in patients with myelodysplastic syndromes and suggest a useful role for routine whole-blood platelet aggregation studies to identify patients at risk of bleeding.
48例骨髓增生异常综合征且血小板计数大于80×10⁹/L的患者成为一项血小板功能研究的对象。使用全血血小板光散射聚集仪通过阻抗法同时测量血小板聚集和三磷酸腺苷致密颗粒释放。结果与皮肤出血时间以及临床出血或血栓形成事件相关。35例患者至少有1项异常结果提示血小板活性减低；7例患者血小板活性减低与亢进并存；4例患者血小板活性亢进。只有2例患者结果正常。血小板活性减低与皮肤出血时间延长之间存在良好相关性（P = 0.005）；然而，几名血小板活性减低的患者皮肤出血时间正常。这一发现提示全血血小板聚集研究在识别出血风险患者方面可能比出血时间更敏感。尽管该队列患者血小板计数大于100×10⁹/L，但临床出血很常见（32例患者）。这一发现表明血小板功能低下具有临床重要性。相比之下，13例发生血栓事件的患者中只有2例有血小板活性亢进的证据，提示其他临床因素可能是血栓形成更重要的决定因素。这些观察结果证实血小板功能障碍在骨髓增生异常综合征患者中很常见，并提示常规全血血小板聚集研究在识别出血风险患者方面具有有用作用。
