Division of Pediatrics, Department of Homeostatic Regulation and Development, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.
Am J Med Genet A. 2012 Mar;158A(3):630-4. doi: 10.1002/ajmg.a.34424. Epub 2012 Feb 2.
Hypochondroplasia (HCH) is the mildest phenotype among fibroblast growth factor receptor 3 (FGFR3)-associated skeletal dysplasias. Affected individuals usually presents with mild short stature in preschool age. It was uncommon that a diagnosis of HCH is made in young affected children. Recently, however, prenatal ultrasound (US) has increased likelihood of detecting in utero mild short limbs. There have been a few reports on the early diagnosis of HCH in the neonatal period preceded by a suspicion of skeletal dysplasia on fetal US. However, the proper diagnosis of HCH is hampered by absence of the radiological criteria relevant to age, particularly those in the neonatal period. We report on the clinical and radiological findings in two HCH children with a FGFR3 mutation. In both children, fetal US showed short femora and relatively increased biparietal diameter (BPD). However, postnatal assessment failed to make a specific diagnosis in the neonatal period. The correct diagnosis of HCH was accomplished by reassessment after exacerbation of postnatal short stature. In retrospective radiological review, the radiological findings relevant to HCH were discernible more easily in the neonatal period than at age of 3 years.
软骨发育不全症（HCH）是成纤维细胞生长因子受体 3（FGFR3）相关骨骼发育不良中最轻微的表型。受影响的个体通常在学龄前表现出轻度身材矮小。在年幼的受影响儿童中做出 HCH 诊断并不常见。然而，最近产前超声（US）增加了在子宫内检测到轻度短肢的可能性。已经有一些关于 HCH 在新生儿期早期诊断的报告，这些报告在前胎儿 US 怀疑骨骼发育不良的情况下进行。然而，由于缺乏与年龄相关的放射学标准，尤其是在新生儿期，HCH 的正确诊断受到阻碍。我们报告了两名 FGFR3 突变的 HCH 患儿的临床和放射学发现。在这两个孩子中，胎儿 US 显示股骨短，双顶骨直径（BPD）相对增加。然而，在新生儿期，产后评估未能做出明确诊断。在产后身材矮小恶化后重新评估，做出了正确的 HCH 诊断。回顾性放射学检查发现，HCH 的放射学发现更容易在新生儿期而不是 3 岁时发现。
