以反复骨折为特征青少年男性成骨不全症1例探讨

Osteogenesis imperfecta in adolescent male characterized by recurrent fractures:a case report

目的总结1例以反复骨折为特征的青少年男性患者的诊治和随访过程,探讨青少年骨质疏松症的鉴别诊断及成骨不全症(osteogenesis imperfecta,OI)的诊断与治疗。方法1例自幼起病的青少年男性患者,10年内反复骨折8次,采集患者病史等临床资料,收集相关生化检测指标和双能X线吸收测量仪(dual-energy X-ray absorptiometry,DXA)骨密度、高分辨外周骨定量CT(high-resolution peripheral quantitative computed tomography,HR-pQCT)及X片检查结果;采用全外显子测序法检测患者及其家系成员的基因。结果患者轮椅推入,查体见轻度蓝巩膜,指间关节韧带略松弛,生化检查未见明显异常,DXA骨密度Z值在正常范围,HR-pQCT提示骨质疏松症,X片提示四肢骨质稀疏、骨皮质变薄,全外显子基因检测到BMP1突变[NM_006129.4:c.171C>T(p.Ala57Ala)]。给予钙剂、维生素D及静脉双膦酸盐治疗,结合康复锻炼,患者体力恢复良好,行走、活动恢复,随访1年未再发生跌倒及骨折。结论对可疑青少年骨质疏松症,伴反复脆性骨折者,应注意继发性骨质疏松症的鉴别,并考虑到遗传性骨病,尤其是OI的可能性。OI诊断主要依据临床表现及影像学特点,基因检测作为辅助诊断。双膦酸盐类药物对OI的疗效确定,但其用药周期及不良反应尚有待于进一步研究。

Objective To summarize the diagnosis,treatment,and follow-up of an adolescent male with recurrent fractures,to explore the differential diagnosis of adolescent osteoporosis and the treatment of osteogenesis imperfecta(OI).Methods A 15-year-old boy was admitted to our hospital with 8 times fractures in 10 years.The patient's medical history and clinical data were collected.Biochemical data,results of dual-energy X-ray absorptiometry(DXA)bone mineral density,high-resolution peripheral quantitative computed tomography(HR-pQCT),and X-ray examination were conducted.The gene mutation of the patient and his family members was detected by whole exons sequencing(WES).Results The patient was wheeled when he came to our hospital first time,and physical examination showed mild blue sclera,slightly relaxed interphalangical ligament.Biochemical examination showed no obvious abnormality.The Z score of bone mineral density was in normal range,but HR-PQCT suggested low bone mineral density.X-ray suggested sparse bone of limbs and thinning of bone cortex.BMP1 mutation[NM_006129.4:c.171C>T(p.Ala57Ala)]was found in the WES.With calcium and vitamin D supplement,intravenous bisphosphonate therapy,combined with rehabilitation exercise,the patient recovered well physically,walked freely.No fall and fracture happened during 1 year follow up.Conclusions In case of adolescent osteoporosis,especially with repeated fragile fractures,attention should be paid to the identification of secondary osteoporosis,and the possibility of hereditary bone diseases,especially OI,should be taken into account.The diagnosis of OI is mainly based on clinical manifestations and imaging features,with genetic testing as an confirmation diagnosis.Bisphosphonates are the optimal treatment for OI,but medical duration and adverse effects remain to be further clarified.