UNASSIGNED: Diagnosis of MPS IVA was made based on whole-exome sequencing (WES) of blood samples collected from the patient and family members, high urinary glycosaminoglycan excretion, supportive clinical manifestations, radiographic examinations, including whole-body X-rays, cervical MRI, and pelvic CT. The patient underwent bilateral total hip arthroplasties sequentially, at a 1-month interval. Femoral heads were preserved for the micro-CT (μCT) analysis and the osteochondral histology examination.
UNASSIGNED: The patient presented with multiple skeletal deformities, including vertebras and long bone deformities. WES disclosed compound heterozygous variants at exon 11 (c.1156C>T) and exon 12 (c.1288C>G) of the GALNS (NM_000512.5). The μCT analysis revealed significant bone quantity loss and microarchitectural change in both weight-bearing area (WBA) and non-weight-bearing area (NWBA) of the femoral heads, while histological analysis showed structural abnormity of articular cartilage in the WBA of the femoral heads.
UNASSIGNED: We have found compound heterozygous variants of GALNS. This is also the first study to report the microarchitectural and histological changes of both subchondral bone and articular cartilage of the femoral head in a patient with MPS IVA.
■MPSIVA的诊断是根据从患者和家庭成员收集的血液样本的全外显子组测序(WES)进行的,尿糖胺聚糖排泄高,支持性临床表现,射线照相检查,包括全身X光,宫颈MRI,盆腔CT。患者依次接受双侧全髋关节置换术,间隔1个月。保留股骨头进行显微CT(μCT)分析和骨软骨组织学检查。
■患者表现为多发性骨骼畸形,包括椎骨和长骨畸形。WES公开了GALNS(NM_000512.5)的外显子11(c.1156C>T)和外显子12(c.1288C>G)的复合杂合变体。μCT分析显示股骨头的负重区(WBA)和非负重区(NWBA)的骨量减少和微观结构改变,而组织学分析显示股骨头WBA关节软骨结构异常。
■我们发现了GALNS的复合杂合变体。这也是第一项报道MPSIVA患者的软骨下骨和股骨头关节软骨的微观结构和组织学变化的研究。