SPONASTRIME Dysplasia: Report of an 11-year-old Boy and Review of the Literature

SPONASTRIME (SPOndylar and NAsal changes, with STRIations of the MEtaphyses) dysplasia is a rare, autosomal recessive bone disorder first described by Fanconi et al. [1983: Helv Paediatr Acta 38:267-280]. Radiographic findings include abnormal vertebral bodies with age-dependent changes, and striations of the metaphyses, scoliosis, and retarded ossification of the carpal bones. Physical features include severe short stature, lumbar lordosis, midface hypoplasia, frontal bossing, and a depressed nasal root. To date, 12 patients from 6 families have been reported. Four additional patients have been reported with a variant of this condition, which includes mental retardation. We report on an 11-year-old boy with features consistent with SPONASTRIME dysplasia. Height was 106.1 cm (-6 SD). He had a coarse appearing face with a depressed nasal bridge, short, upturned nose, and midface hypoplasia. Intelligence was normal. A clinical evaluation at 6 years of age suggested the diagnosis of spondyloepiphyseal dysplasia (SED). However, genetics evaluation at 11 years of age with repeat radiologic studies revealed delayed carpal ossification (-4 to -5 SD), metaphyseal irregularities and striations most notably in the distal femurs and the proximal tibias, lumbar lordosis, narrow interpedicular distances of the lumbar spine, and pear-shaped vertebral bodies. These findings were most consistent with the diagnosis of SPONASTRIME dysplasia, and not SED. Although radiographic findings of SPONASTRIME dysplasia are distinguishable from SED, the physical appearance may be similar. Many bone dysplasias have overlapping radiographic findings and clinical presentation but with different recurrence risks, making genetic counseling a challenge.