Spondyloenchondrodysplasia with immune dysregulation related to ACP5. A report of 4 cases

Spondyloenchondrodysplasia with immune dysregulation related to ACP5 (SPENCDI, OMIM number 607944) is an uncommon immune-skeletal dysplasia with heterogeneous manifestations and variable severity.It is characterized by spondylar and metaphyseal lesions, immune dysfunction, and neurological involvement.Here we report the clinical, radiological and genetic aspects of 4 girls with SPENCDI treated at a children's hospital.They all had skeletal manifestations and 3 developed severe immune disease.In 3 patients, the likely pathogenic variant c.791T>A; p.Met264Lys (homozygous mutation) was observed, while 1 patient had variants c.791T>A; p.Met264Lys and c.632T>C; p.lle211Thr (variant of uncertain significance with pathogenic prediction based on bioinformatics algorithms) caused by a compound heterozygous mutation in ACP5.The repeated presence of variant c.791T>A suggests the possibility of a common ancestor in our population.The recognition and diagnosis of this disorder is important to achieve a timely approach, which should be multidisciplinary and aimed at preventing possible complications.