Objective: To analyze the clinical, laboratory characteristics and PIG-A gene mutations in patients of myelodysplastic syndromes (MDS) with PNH clones.
Methods: 218 MDS patients diagnosed from August 2013 to August 2015 were analyzed. The PIG-A gene mutations were tested in 13 cases of MDS with PNH clones, 17 cases of AA-PNH and 14 cases of PNH selected contemporaneously by PCR and direct sequencing.
Results: 13 (5.96%) MDS patients were detected with PNH clones (13/218 cases). 9 patients were treated with cyclosporin A (CsA). Patients showed hematological improvement (HI). There were significant differences between MDS-PNH and PNH patients in terms of granulocyte clone size, red cell clone size and LDH levels [19.2% (1.0%-97.7%) vs 60.2% (3.1%-98.0%), P=0.007; 4.3% (0-67.2%) vs 27.9% (2.5%-83.6%), P=0.026; 246 (89-2014) U/L vs 1137 (195-2239) U/L, P=0.049], while the differences were not statistically significant in patients between MDS-PNH and AA-PNH patients [19.2% (1.0%-97.7%) vs 23.2% (1.5%-96.0%), P=0.843; 4.3% (0-67.2%) vs 14.4% (1.1%-62.8%), P=0.079; 246 (89-2014) U/L vs 406 (192-1148) U/L, P=0.107]. PIG-A gene mutations were detected in 7 MDS-PNH patients, of them, six were missense mutations, one were frameshift mutation and four cases with the same mutation of c.356G>A (R119Q). The PIG-A gene mutations were also detected in 9/11 AA-PNH patients and 11/14 PNH patients, both of them had the mutation of c.356G>A (R119Q). The PIG-A gene mutations of MDS-PNH, AA-PNH, PNH patients were all small mutations, the majority of those (59%) were missense mutation and mainly located in exon 2.
Conclusion: MDS patients with PNH clones had better response to CsA, smaller PNH clone size. The PIG-A gene mutations of MDS-PNH patients mainly located in exon 2, which could be a mutational hotspot of these patients.
目的: 分析伴阵发性睡眠性血红蛋白尿症克隆的骨髓增生异常综合征（MDS-PNH）患者的临床特征及PIG-A基因突变等实验室特征。
方法: 回顾性分析2013年8月至2015年8月诊治的218例MDS患者，其中经流式细胞术检出MDS-PNH 13例，选取同期17例再生障碍性贫血（AA）-PNH综合征患者及14例PNH患者，采用直接测序法分析PIG-A基因突变情况，比较各组患者的临床及实验室特征。
结果: MDS-PNH患者在MDS患者中的比例为5.96%（218例中13例），其中9例MDS-PNH患者使用环孢素A（CsA）治疗，8例获得血液学改善（HI）。MDS-PNH患者粒、红细胞PNH克隆大小及LDH水平[分别为19.2%（1.0%~97.7%）、4.3%（0~67.2%）、246（89~2 014）U/L]与PNH患者[分别为60.2%（3.1%~98.0%）、27.9%（2.5%~83.6%）、1 137（195~2 239）U/L]比较差异均有统计学意义（P值分别为0.026、0.007、0.049），与AA-PNH综合征患者[分别为23.2%（1.5%~96.0%）、14.4%（1.1%~62.8%）、406（192~1 148）U/L]比较差异均无统计学意义（P值均>0.05）。7例MDS-PNH患者检测到PIG-A基因突变，错义突变6例，移码突变1例，4例患者有相同的突变，为c.356G>A（R119Q）；9例AA-PNH综合征和11例PNH患者PIG-A基因突变，均存在c.356G>A（R119Q）。3组患者的PIG-A基因突变均为小克隆突变，以错义突变为主，59%（19/32）的突变发生在2号外显子。
结论: MDS-PNH患者CsA治疗效果好，PNH克隆较小，基因突变主要集中在2号外显子，可能存在突变热点。