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Sudden death in spondylo-meta-epiphyseal dysplasia, short limb-abnormal calcification type
Cristina Dias1, Robyn Cairns, Millan S Patel
1Centro de Genética Médica Doutor Jacinto Magalhães, Porto, Portugal Departments of Medical Genetics Diagnostic Imaging, University of British Columbia, Vancouver, BC, Canada.
Abstract:
The spondylo-meta-epiphyseal dysplasias are an expanding group of skeletal dysplasias with specific features differentiating each subtype. We review the precocious carpal mineralization, unique metacarpal shape, triangular distal phalanges and mushroom cloud-shaped proximal phalanges present at an early age in spondylo-meta-epiphyseal dysplasia, short limb-abnormal calcification type (SMED SL-AC) and report two patients with clinical and radiographic features consistent with SMED SL-AC, who died suddenly because of spinal cord compression. The patients presented are female siblings, providing further evidence for autosomal recessive inheritance. Cervical cord compression is found in half of reported patients and is the major cause of mortality. SMED SL-AC should be added to the list of genetic causes of sudden death. Radiological features in the hand may be used in the first few years of life to support an early diagnosis and thus allow for prevention of premature demise.
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