STANKIEWICZ–ISIDOR SYNDROME CAUSED BY A MICRODELETION OF THE LONG ARM OF CHROMOSOME 17: A CASE REPORT AND LITERATURE REVIEW

Abstract

Stankiewicz–Isidor syndrome (STISS; OMIM #617516) is a rare autosomal dominant disorder caused by haploinsufficiency of the PSMD12 gene. Most reported cases are associated with point variants in the PSMD12 gene, whereas microdeletions involving this locus are much rarer. We present a clinical case of an 8-month-old girl with psychomotor developmental delay, muscular hypotonia, craniofacial anomalies, and congenital heart defect. Standard karyotyping revealed no pathology. Whole-exome sequencing suggested a microdeletion of chromosome 17. Chromosomal microarray analysis (CMA) revealed a heterozygous 3.42 Mb microdeletion at 17q23.3q24.2, including the PSMD12 gene and a number of neighboring genes. The patient's phenotype was largely consistent with literature data; however, the presence of a pilonidal sinus has not been previously described in patients with STISS. Conclusion: this case report expands the current understanding of the phenotypic spectrum of Stankiewicz–Isidor syndrome and highlights the high diagnostic value of CMA in patients with syndromic pathology and normal karyotype.