中文摘要：

目的探讨特发性血小板减少性紫癜（ITP）的发病机制并探讨其与骨髓增生异常综合征（MDS）的鉴别诊断。方法用聚合酶链反应-单链构象多态性（PCR-SSCP）方法检测MDS患者突变频率较高的NRAS基因12、13密码子及FMS基因301、969密码子点突变在中老年ITP患者及MDS患者中的出现频率。结果25例ITP患者中有1例存在NRAS基因突变，1例存在FMS基因301密码子突变；8例MDS患者中有3例出现基因突变，其中2例为NRAS基因突变，1例为FMS基因突变。结论PCR-SSCP方法检测NRAS基因12、13密码子，FMS基因301、969密码子突变有可能用于鉴别诊断ITP与MDS，ITP患者中出现NRAS基因、FMS基因突变者应归入MDS。

英文摘要：

Objective To explore the pathogenesis of idiopathic thrombocytopenic purpura（ITP） and improve the differential diagnosis from myelodysplastic syndromes（MDS）. Methods Polymerase chain reaction-single strand conformation polymorphism （PCR-SSCP） was performed to detect the point mutation of codon 12,13 in N-ras gene and codon 301, 969 in fms gene in adult and aged ITP and MDS patients. Results In 25 ITP patients, N-ras mutation and fms mutation were detected in one each （4%）. Mutations were found in 3 of 8 MDS patients： two （25%） with N-ras mutation and one （12.5%） with fins mutation. Conclusions Patients with N-ras or fms gene mutation diagnosed as MDS rather than ITP.