Pediatric floating-harbor syndrome: clinical features and treatment outcomes in a cohort of Chinese children.

Floating-Harbor syndrome (FHS) is a rare disorder characterized by facial dysmorphism, short stature, and delayed language development. We evaluated the clinical features and treatment outcomes of 10 Chinese children with FHS who received recombinant human growth hormone (rhGH) therapy or nutritional intervention. We retrospectively extracted the clinical features, height standard deviation score (SDS), genetic characteristics, and treatment outcomes from the medical records of 10 Chinese children with FHS. The treatment response was classified as good, moderate, or poor based on annual height SDS change and height velocity. All patients presented with short stature at diagnosis, distinct facial features, and non-specific skeletal abnormalities. All patients had delayed language development, feeding difficulties, intellectual disability, and diverse organ abnormalities. Whole-exome sequencing (WES) identified pathogenic or likely pathogenic variants in exon 34 of SRCAP, and eight mutations were identified, including three variants (c.7225dupG;p.Ala2409GlyfsTer34, c.7382delC;p.Pro2461GlnfsTer 14, and c.7255C > T;p.Gln2419Ter) that had not been previously reported in case reports. Eight patients were treated with rhGH, six of whom demonstrated good responses, one a moderate response, and one a poor response. One patient with a contraindication to rhGH treatment achieved meaningful height SDS improvement after nutritional therapy.

conclusionAlthough FHS is a rare condition, we characterized its clinical features in a Chinese patient cohort. RhGH improved height in most patients, and nutritional optimization appeared to support growth in one child. WHAT IS KNOWN: • Floating-Harbor syndrome (FHS) is a rare genetic disorder characterized by facial dysmorphism and short stature, and it is often treated with growth hormone. The majority of documented cases of FHS have historically been concentrated within Western populations. The number of cases reported in Asian countries remains small. WHAT IS NEW: • We report three SRCAP variants that have not been previously documented in case reports among 10 Chinese children with FHS. Most children showed favorable short-term responses to recombinant human growth hormone, and one child demonstrated an improvement in height standard deviation score with structured nutritional therapy alone.