Type of dwarfism characterized by enchondromatosis with marked involvement of the spine.
Spondylo-Enchondromatosis; Spondylo-Metaphyseal Dysplasia with Enchondromatous Changes; SPENCD Syndrome.
Very rare. Fewer than 50 individuals described.
Biallelic mutations in ACP5 on 19p13.2, which encodes a tartrate-resistant acid phosphatase (TRAP).
Clinical and radiological features. Radiograph of vertebral spine typically shows platyspondyly ie, congenital flattening of the vertebral bodies, which is often accentuated dorsally, and frequently associated with a spina bifida. Radiograph of long bones shows the metaphyses as irregular and slightly widened with varying radiolucent lesions. Radiolucent areas may also be present in diaphyses, epiphyses, iliac crest, scapulae, and sternum.
Common clinical features include growth retardation, minor craniofacial anomalies, and peculiar enchondromatous changes in skeletal bones. Growth: short limbs, short trunk, short stature. Craniofacial: dolichocephaly, frontal bossing, mild midface hypoplasia. Skeletal: increased lumbar lordosis; kyphoscoliosis; barrel chest; genu valgum or varus; short, broad hands. Neurology: variable mental capacity, ranging from mostly normal intelligence to occasionally moderate retardation. A Type 2 has been described with the presence of calcification of basal ganglia on CT scan and associated with progressive spastic quadriparesis. A spina bifida is often present.
Precautions before anesthesia
A careful evaluation of the airway must be conducted to eliminate a potentially difficult airway management.
No specific consideration. The possibility of difficult airway management must be anticipated because of the craniofacial anomalies, ie, a large head, midface hypoplasia, and cervicothoracic vertebral fusion. Care in positioning of patient must be provided because of the increased lumbar lordosis, large head, and short limbs.
There are no known specific implications with this condition.
et al: Spondyloenchondrodysplasia due to mutations in ACP5: A comprehensive survey. J Clin Immunol
et al: Possible heterogeneity in spondyloenchondrodysplasia: Quadriparesis, basal ganglia calcification, and chondrocyte inclusions. Am J Med Genet
J: Spondyloenchondrodysplasia. J Med Genet