目的 探讨先天性纯红细胞再生障碍性贫血(DBA)的临床特点及其致病基因。方法 回顾分析2例DBA患 儿的临床资料以及基因检测结果,同时复习相关文献。结果 两例患儿均为女性,分别为3月龄和4月龄;均以面色苍黄 就诊。血常规红细胞偏低、血红蛋白低、网织红细胞计数低;血清铁及铁蛋白均升高;红细胞脆性实验未见异常。骨髓细 胞学均提示髓象幼红细胞罕见。基因检测,例1的RPS19存在c.91C>T(p. P31S)杂合突变,其父母未见突变,该突变为新 发突变,经验证为致病基因;例2的RPL5基因存在c.472_473del缺失突变(p.K158fs),为已知致病基因。结论 DBA患 儿多在出生早期发病,临床表现为红系缺乏,RPS19及RPL5基因突变较常见,相关基因检测有利于早期诊断;c.91C>T(p. P31S)杂合突变为未见报道的新突变。
Objective To investigate the clinical and genetic features of Diamond-Blackfan anemia (DBA). Method The clinical manifestations and genetic tests of 2 cases with DBA were retrospectively analyzed, and the related literatures were reviewed. Results Two female patient (3-4 month old)with progressive ochriasis nearly a month was included. Fever, seizure, vomit and abnormal change in urine and stool routine test were not shown. Blood routine test: the number of RBC in the two patients was decreased(1.24 ×1012/L and 1.48×1012/L), HGB (46 g/L and 39 g/L), and the number of RTC was also decreased (4.1×109/L and 4.3×109/L), RCV was normal (108.4 fl). Serum iron determination: Fe (44.3 mmol/L and 41.5 mmol/L) and ferritin (469.2 mmol/L and 491.7 ng/mL) were increased, transferrin was in the normal range. Erythrocyte fragility test resulted normal. Bone marrow examination found rarely erythroblasts. A novel heterozygous mutation in RPS19 gene, c.91C>T(p. P31S), was found by genetic testing on patient 1. And we found a heterozygous mutation in RPL5 gene (c.472_473del) in patient 2. Conclusion The majority of onset age of childhood DBA was within a few months with a erythroid deficiency. And RPS19 gene mutation is a common cause of this disease. The mutation of c.91C>T (p. P31S) has not been reported.